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Medium-scale pig production systems, which make up 30 % of Mexico's pig farms, face two key obstacles impacting their economic and financial performance. The first is the absence of a sales plan based on pigs' weight, which negatively affects both profitability and resource management. The second obstacle is inadequate waste management, which hampers efforts to mitigate environmental impacts generated by pig farms. Based on this criterion, this study aims to determine technical and economic optimum levels of a medium-scale pig farm and evaluate its associated environmental impacts. Based on the last farm sale weight (116.3 kg - base scenario), technical and economic optimum levels were estimated using a production function, resulting in a technical optimum of 155 kg and an economic optimum of 127 kg. An environmental assessment of the pig fattening process was carried out following the principles of the Life Cycle Analysis methodological framework. Using a cradle-to-farm gate perspective, and establishing 1 kg of live-weight pig as the functional unit. The results indicated that production at maximum weight level (155 kg), increased environmental impacts by 60 % to 75 % compared to the base scenario. In contrast, at the maximum economic benefit level (127 kg), environmental impacts increased by 5 % to 10 %. Feed production represented the largest contribution (over 74 %) in six impact categories. The results provide valuable information for medium-scale pig farms to mitigate the environmental burdens associated with the optimal production weight and to direct efforts towards achieving future economic and environmental efficiency.
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Crianza de Animales Domésticos , Ambiente , Animales , México , Crianza de Animales Domésticos/métodos , Porcinos , GranjasRESUMEN
Aneurysms are clinical entities that can develop and affect human aorta; and although in most cases they have an asymptomatic course, these pathological dilatations can lead to a lethal outcome when rupture occurs, thus the establishment of predictors is crucial for death prevention. Essential events that take place in the vessel wall have been identified and described, such as inflammation, proteolysis, smooth muscle cell apoptosis, angiogenesis, and vascular remodeling. Porcine and ovine models have been useful for the development and evaluation of endovascular devices of the aorta. However, since the worldwide introduction and adoption of these minimally invasive techniques for aneurysm repair, there is lesser availability of diseased aortic tissue for molecular, cellular, and histopathological analysis, therefore over the last three decades it has been proposed various small species models that have allowed the focal induction of these lesions for the study of physiopathological mechanisms and possible useful biomarkers as diagnostic and therapeutic targets. The present review article presents and discusses the animal models available as their applications, characteristics, advantages, and limitations for the development of preclinical studies, and their importance in the comprehension of this pathology in humans.
Los aneurismas son una de las entidades clínicas que pueden desarrollarse y afectar la aorta humana. Aunque en la mayoría de los casos tienen un carácter asintomático, estas dilataciones patológicas pueden resultar letales cuando se presentan con ruptura, por lo que el reconocimiento de factores predictores de esta complicación es crucial para evitar muertes. Fisiopatológicamente se han identificado eventos esenciales que ocurren en la pared del vaso, como inflamación, proteólisis, apoptosis del músculo liso, angiogénesis y remodelación. Las grandes especies como porcinos y ovinos han sido de utilidad para el desarrollo y evaluación del desempeño de dispositivos endovasculares en la aorta, así como la remodelación; con el advenimiento y disposición de estas técnicas mínimamente invasivas para su reparación existe una menor disponibilidad de tejido aórtico para el análisis molecular, celular e histopatológico, por lo que en las últimas tres décadas se han propuesto e introducido distintos modelos que han permitido, mediante la inducción focal de estas lesiones, el estudio de los mecanismos fisiopatológicos y posibles biomarcadores de utilidad como dianas diagnósticas y terapéuticas. El presente artículo de revisión aborda tipos de modelos animales disponibles, así como sus aplicaciones, consideraciones, ventajas y limitaciones para el desarrollo de estudios preclínicos y su importancia en el entendimiento de esta patología en la especie humana.
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Aneurisma de la Aorta Abdominal , Aneurisma de la Aorta Torácica , Modelos Animales de Enfermedad , Animales , Aneurisma de la Aorta Abdominal/patología , Aneurisma de la Aorta Torácica/cirugía , HumanosRESUMEN
Arterial diseases are prevalent in the general population, particularly in the elderly, and they are among the main causes of morbidity and mortality worldwide. Nuclear imaging is a useful tool in diagnosis and follow-up in different areas of medicine, and over the last 2 decades, these study modalities have become more relevant in the field of angiology and vascular surgery due to their potential benefit in the interpretation of pathophysiological mechanisms associated with the natural history and severity of diseases that affect the circulation such as vasculitis, degenerative aortic aneurysms (AA), peripheral arterial disease (PAD), and complications following reconstructive procedures such as graft infections. The literature has shown evidence of an important number of radiotracers for specific molecules involved in the activity of these entities and their utility as predictors during surveillance and possible therapeutic targets. The present narrative review aims to describe the use of nuclear medicine, imaging methods, and radiotracers that have been applied in arterial diseases, as well as the advantages and considerations, their importance in the diagnosis and follow-up of these complex groups of patients, and future perspectives.
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Fasciola hepatica is distributed worldwide, causing substantial economic losses in the animal husbandry industry. Human fasciolosis is an emerging zoonosis in Andean America, Asia, and Africa. The control of the disease, both in humans and animals, is based on using anthelmintic drugs, which has resulted in increased resistance to the most effective anthelmintics, such as triclabendazole, in many countries. This, together with the concerns about drug residues in food and the environment, has increased the interest in preventive measures such as a vaccine to help control the disease in endemic areas. Despite important efforts over the past two decades and the work carried out with numerous vaccine candidates, none of them has demonstrated consistent and reproducible protection in target species. This is at least in part due to the high immunomodulation capacity of the parasite, making ineffective the host response in susceptible species such as ruminants. It is widely accepted that a deeper knowledge of the host-parasite interactions is needed for a more rational design of vaccine candidates. In recent years, the use of emerging technologies has notably increased the amount of data about these interactions. In the present study, current knowledge of host-parasite interactions and their implication in Fasciola hepatica vaccine development is reviewed.
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Robotic systems are a fundamental part of modern industrial development. In this regard, they are required for long periods, in repetitive processes that must comply with strict tolerance ranges. Hence, the positional accuracy of the robots is critical, since degradation of this can represent a considerable loss of resources. In recent years, prognosis and health management (PHM) methodologies, based on machine and deep learning, have been applied to robots, in order to diagnose and detect faults and identify the degradation of robot positional accuracy, using external measurement systems, such as lasers and cameras; however, their implementation is complex in industrial environments. In this respect, this paper proposes a method based on discrete wavelet transform, nonlinear indices, principal component analysis, and artificial neural networks, in order to detect a positional deviation in robot joints, by analyzing the currents of the actuators. The results show that the proposed methodology allows classification of the robot positional degradation with an accuracy of 100%, using its current signals. The early detection of robot positional degradation, allows the implementation of PHM strategies on time, and prevents losses in manufacturing processes.
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Humanos , Enfermedades Transmisibles , Virosis , Mononucleosis Infecciosa , VIH , Papiloma , Varicela , Herpes ZósterRESUMEN
BACKGROUND: Even though targeted therapies are available for cancers expressing oncogenic epidermal growth receptor (EGFR) and (or) human EGFR2 (HER2), acquired or intrinsic resistance often confounds therapy success. Common mechanisms of therapy resistance involve activating receptor point mutations and (or) upregulation of signaling downstream of EGFR/HER2 to Akt and (or) mitogen activated protein kinase (MAPK) pathways. However, additional pathways of resistance may exist thus, confounding successful therapy. METHODS: To determine novel mechanisms of EGFR/HER2 therapy resistance in breast cancer, gefitinib or lapatinib resistant variants were created from SKBR3 breast cancer cells. Syngenic therapy sensitive and resistant SKBR3 variants were characterized for mechanisms of resistance by mammosphere assays, viability assays, and western blotting for total and phospho proteins. RESULTS: Gefitinib and lapatinib treatments reduced mammosphere formation in the sensitive cells, but not in the therapy resistant variants, indicating enhanced mesenchymal and cancer stem cell-like characteristics in therapy resistant cells. The therapy resistant variants did not show significant changes in known therapy resistant pathways of AKT and MAPK activities downstream of EGFR/HER2. However, these cells exhibited elevated expression and activation of the small GTPase Rac, which is a pivotal intermediate of GFR signaling in EMT and metastasis. Therefore, the potential of the Rac inhibitors EHop-016 and MBQ-167 to overcome therapy resistance was tested, and found to inhibit viability and induce apoptosis of therapy resistant cells. CONCLUSIONS: Rac inhibition may represent a viable strategy for treatment of EGFR/HER2 targeted therapy resistant breast cancer.
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Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Resistencia a Antineoplásicos/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Proteínas de Unión al GTP rac/antagonistas & inhibidores , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Apoptosis , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Carbazoles/farmacología , Carbazoles/uso terapéutico , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/genética , Femenino , Mutación con Ganancia de Función , Gefitinib/farmacología , Gefitinib/uso terapéutico , Regulación Neoplásica de la Expresión Génica , Humanos , Lapatinib , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/genética , Mutación Puntual , Inhibidores de Proteínas Quinasas/uso terapéutico , Pirimidinas/farmacología , Pirimidinas/uso terapéutico , Receptor ErbB-2/antagonistas & inhibidores , Receptor ErbB-2/genética , Esferoides Celulares , Regulación hacia ArribaRESUMEN
AIM: The aim of the present work was to determine if both ovariectomy (OVX) and type 2 diabetes mellitus (T2DM) can change X-ray absorptiometry until reach the osteoporosis condition. RESULTS: The segmentation allowed us to quantitatively determine the X-ray absorption in the femurs of mice subjected to OVX, T2DM and both pathologies together. CONCLUSIONS: The test subjects suffering from the mentioned pathologies separately or together, did not reach the osteoporosis condition when they were 30 weeks old.
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Diabetes Mellitus Experimental/diagnóstico por imagen , Fémur/diagnóstico por imagen , Ovariectomía , Absorciometría de Fotón , Animales , Densidad Ósea , Diabetes Mellitus Experimental/complicaciones , Modelos Animales de Enfermedad , Femenino , Ratones , Osteoporosis/complicaciones , Osteoporosis/diagnóstico por imagenRESUMEN
Physical activity is a priority to improve health. However, a sedentary lifestyle is increasingly becoming the norm. For example, in Mexico, sedentarism has increased, especially among older women. This study evaluated the effects of aquafitness on the health of older women in Mexico. Healthy older women performed aquafitness exercise and were compared to a control group of comparable women. Outcome assessments performed at baseline and after 17-weeks included psychological and physical/anthropometric measures. Participants in aquafitness became more optimistic, lost more weight, body fat, and a subsequent decrease in BMI, compared to controls. The results suggest important avenues for future research.
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Ejercicio Físico , Salud Mental , Anciano , Femenino , Humanos , México , Proyectos Piloto , Conducta SedentariaRESUMEN
The Rho family GTPases Rho, Rac, and Cdc42 have emerged as key players in cancer metastasis, due to their essential roles in regulating cell division and actin cytoskeletal rearrangements; and thus, cell growth, migration/invasion, polarity, and adhesion. This review will focus on the close homologs Rac and Cdc42, which have been established as drivers of metastasis and therapy resistance in multiple cancer types. Rac and Cdc42 are often dysregulated in cancer due to hyperactivation by guanine nucleotide exchange factors (GEFs), belonging to both the diffuse B-cell lymphoma (Dbl) and dedicator of cytokinesis (DOCK) families. Rac/Cdc42 GEFs are activated by a myriad of oncogenic cell surface receptors, such as growth factor receptors, G-protein coupled receptors, cytokine receptors, and integrins; consequently, a number of Rac/Cdc42 GEFs have been implicated in metastatic cancer. Hence, inhibiting GEF-mediated Rac/Cdc42 activation represents a promising strategy for targeted metastatic cancer therapy. Herein, we focus on the role of oncogenic Rac/Cdc42 GEFs and discuss the recent advancements in the development of Rac and Cdc42 GEF-interacting inhibitors as targeted therapy for metastatic cancer, as well as their potential for overcoming cancer therapy resistance.
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OBJECTIVE: To examine heritability of the residual variability of spinocerebellar ataxia type 2 (SCA2) age at onset (AO) after controlling for CAG repeat length. METHODS: From 1955 to 2001, dates of birth, CAG repeat lengths, AO, sex, familial inheritances, and clinical manifestations were collected for a large Cuban SCA2 cohort of 382 affected individuals, including 129 parent-child pairs and 69 sibships. Analyses were performed with log-transformed AO in the GENMOD procedure to predict AO using repeat length, taking into account family structure. Because all relationships were first degree, the model was implemented with an exchangeable correlation matrix. Familial correlations were estimated using the Pedigree Analysis Package to control for similarity due to genetic relatedness. RESULTS: For the entire sample, the mutant CAG repeat allele explained 69% of AO variance. When adjusted for pedigree structure, this decreased to 50%. Evidence for imprinting or sex-specific effects of the CAG repeat on AO was not found. For the entire sample, we determined an upper bound for heritability of the residual variance of 33% (p = 0.008). Heritability was higher in sib-sib pairs, especially in female sib-sib pairs, than in parent-child pairs. CONCLUSIONS: We established that a large proportion of AO variance in SCA2 was determined by genetic modifiers in addition to CAG repeat length. The genetic structure of heritability of the residual AO variance was surprisingly similar to Huntington disease, suggesting the presence of recessive modifying alleles and possibly X-chromosome-linked modifiers.
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Resumen: Introducción: No hay acuerdo en los reportes de la literatura sobre si un índice de masa corporal por arriba de 25 kg/m(2) incrementa, no modifica o disminuye la mortalidad en pacientes en estado crítico. Objetivo: Comparar la mortalidad, morbilidad y consumo de recursos entre individuos con peso normal o bajo (índice de masa corporal IMC < 25 kg/m(2)) versus sujetos con sobrepeso u obesidad (IMC > 25 kg/m(2)). Diseño: Estudio de cohorte prolectiva en una unidad de terapia intensiva. Pacientes: Se incluyeron 159 personas en el estudio. Método: Se colectaron variables demográficas y clínicas, incluyendo peso y talla para calcular el índice de masa corporal. Se registraron datos de escalas de gravedad de la enfermedad SAPS-3, de falla orgánica Bruselas y de intervención terapéutica NEMS (como subrogado de consumo de recursos). El análisis estadístico fue multivariado; fue considerada significativa una p < 0.05. Resultados: Al comparar individuos con IMC < 25 kg/m(2) con aquellos con un IMC mayor no hubo diferencia estadísticamente significativa en mortalidad y consumo de recursos. Sin embargo, al replantear el estudio y comparar sujetos con IMC < a 30 kg/m(2) con aquellos con un IMC mayor, se encontró diferencia significativa en mortalidad entre ambos grupos y un tamaño del efecto considerable en cuanto a consumo de recursos en personas con un IMC > 30 kg/m(2). Conclusiones: En México debemos cambiar el punto de corte del índice de masa corporal a 30 kg/m(2) cuando comparemos mortalidad y consumo de recursos en los enfermos internados en la UTI. Este estudio abre la posibilidad de realizar un estudio multicéntrico para confirmar estos resultados.
Abstract: Introduction: There is disagreement over if a body mass index (BMI) above 25 kg/m(2) increases, decreases or does not alter the mortality in critically ill patients. Objective: To compare the mortality, morbidity and resource use among patients with normal or low body mass index (< 25 kg/m(2)) versus patients with overweight or obesity (> 25 kg/m(2)). Design: Study of a prolective cohort in an intensive care unit. Patients: One hundred fifty-nine patients were included in the study. Methods: Demographic and clinical data (including weight and height for the calculation of the body mass index) were collected, as well as scores of severity of illness SAPS-3, organic failure (Brussels) and therapeutic intervention NEMS (as a surrogate marker of resource use). The statistical analysis was multivariate, with a significance of p < 0.05. Results: When we compared patients with a BMI < 25 kg/m(2) versus those with BMI above 25 kg/m(2), we did not find statistical differences in mortality and resource use. However, when we changed the cutoff point of BMI to 30 kg/m(2), we found statistically significant differences in mortality and an important effect size in the resource use between both groups. Conclusions: In México we should change the cutoff point of the body mass index to 30 kg/m(2) when we compare mortality and resource use in those patients in the ICU. This study suggests the possibility of making a multicenter study to confirm these findings.
Resumo: Introdução: Não há nenhum acordo nos relatos da literatura se um índice de massa corporal acima de 25 kg/m(2) incrementa, não altera ou diminui a mortalidade em pacientes em estado crítico. Objetivo: Comparar a mortalidade, morbidade e consumo de recursos entre os pacientes com peso normal ou baixo (índice de massa corporal IMC < 25 kg/m(2)) versus pacientes com sobrepeso e obesidade (IMC > 25 kg /m(2)). Desenho: Estudo prospectivo de coorte. Pacientes: 159 pacientes foram incluídos no estudo. Método: Foram coletadas variáveis demográficas clínicas, incluindo peso e altura para calcular o índice de massa corporal. Foram coletados dados da escala de gravidade da doença SAPS-3, a falha orgânica Bruselas e a intervenção terapêutica NEMS (como o consumo de recursos sub-rogado). A análise estatística foi multivariada considerando significativa uma p < .05. Resultados: Ao comparar os pacientes com IMC < 25 kg/m(2) com aqueles com um IMC superior não houve diferença estatisticamente significativa na mortalidade e consumo de recursos. No entanto, ao reformular o estudo e comparar pacientes com IMC < 30 kg/m(2) com aqueles com um IMC superior, se encontrou uma diferença significativa na mortalidade entre os dois grupos e um impacto significativo em termos de consumo de recursos em pacientes com IMC > 30 kg/m(2). Conclusões: No México temos que mudar o ponto de corte do índice de massa corporal à 30 kg/m(2) quando comparamos a mortalidade e o consumo de recursos em pacientes internados na UTI. Este estudo abre a possibilidade de um estudo multicêntrico para confirmar estes resultados.
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This article provides relevant results of a cleaner production program conducted in a company dedicated to remanufacturing air compressors in the city of Hermosillo, Sonora, Mexico. The overall study design was based on an integration of acknowledged cleaner production and pollution prevention programs. Although this kind of program also involves environmental issues, this study focused on occupational health and safety by addressing different aspects of the work environment: ergonomic, physical (noise and lighting), and chemical. Particularly, ergonomic aspects were evaluated through the Modular Arrangement of Predetermined Time Standards (MODAPTS) method. For physical aspects, noise and lighting were addressed through Standard No. NOM-011-STPS-2001 and Standard No. NOM-025-STPS-2008 respectively. In addition, chemical aspects were analyzed through material safety data sheets and different search tools. Root causes of each risk were identified, and options to prevent, eliminate, and/or reduce each risk have been provided.
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Ergonomía , Exposición Profesional/prevención & control , Salud Laboral , Contaminación del Aire Interior/prevención & control , Sustancias Peligrosas , Humanos , Iluminación , Instalaciones Industriales y de Fabricación/normas , México , Ruido en el Ambiente de Trabajo/prevención & controlRESUMEN
La elevada importancia que ha tenido el desarrollo y utilización adecuada de la radiología (actualmente imagenología) para el diagnóstico de diversas afecciones médicas en el presente siglo, especialmente en las últimas décadas, unida a la ausencia de investigaciones relacionadas con el surgimiento y evolución de dicha especialidad en nuestra localidad, sustenta la necesidad de brindar un mayor conocimiento de la historia de la Radiología en Cienfuegos. El objetivo de este estudio es exponer los elementos relacionados con el surgimiento y desarrollo de la Radiología en Cuba, particularmente en Cienfuegos, así como los beneficios que ha traído a la población de esta ciudad. Para ello se realizó un estudio cualitativo, de perfil histórico y descriptivo. Se exponen aspectos relacionados con la asistencia y la docencia del personal no médico y se hace alusión a diversas personalidades relevantes vinculadas a esta actividad. El surgimiento de la Radiología en la provincia se remonta a los primeros años de la segunda década del 1900, sin embargo, no fue hasta después del triunfo de la revolución en 1959, que experimentó un verdadero avance tecnológico.
The need of providing a better understanding of Radiology in Cienfuegos, is founded on the importance the development and the adequate use of Radiology (currently imaging) has had for the diagnosis of diverse medical conditions in the present century, specially in the last decades, so as the absence of research associated to the origin and evolution of this specialty in the locality. The objective of this paper is to present the elements related with the emergence and development of Radiology in Cuba, particularly in Cienfuegos, and the benefits it has brought about for the population of this city. Aimed at that, a qualitative study was carried out, with a historical and descriptive profile. Aspects related to non medical personnel assistance and teaching are presented and it is alluded to diverse relevant personalities linked to this activity. The emergence of Radiology in the province dates back to the early years of the second decade of 1900, however, it was not until after the triumph of the revolution in 1959, which experienced true technological advances.
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Objetivo: actualizar conceptos sobre el funcionamiento de las hormonas tiroideas en pequeños rumiantes. Materiales y Métodos: mediante la revisión de la literatura disponible de los últimos 50 años en las bases de datos BBCS-LILACS, Fuente Académica, IB-PsycINFO, IB-SSCI, IB-SciELO, SCOPUS y SCIRUS, al igual que artículos históricos, textos y referencias citadas en trabajos. Resultados: la información obtenida relacionada con los objetivos propuestos en la presente revisión, permite clasificar en cinco secciones a saber: funciones de las hormonas tiroideas; hormonas tiroideas y la reproducción de pequeños rumiantes; las hormonas tiroideas y el desarrollo fetal; hormonas tiroideas, preñez y lactancia; y factores que alteran los niveles de hormonas tiroideas. Conclusión: el buen funcionamiento de las vías metabólicas depende en gran parte de las hormonas tiroideas, por sus efectos específicos sobre diferentes órganos, manteniendo la homeostasis entre todos los tejidos.
Objective: To update concepts on thyroid hormones functioning in small ruminants. Materials and methods: Through available literature review from the last 50 years in the BBCS-LILACS, Fuente Académica, IB-PsycINFO, IB-SSCI, IB-SciELO, SCOPUS, and SCIRUS data bases as well as historical articles, texts and references cited in published work. Results: Information obtained related to the objectives proposed in the present review allows to classify into five sections as follows: thyroid hormones functioning; thyroid hormones and reproduction of small ruminants; thyroid hormones and fetal development; thyroid hormones, pregnancy and lactation; and factors that alter thyroid hormones levels. Conclusion: The proper functioning of metabolic pathways depends largely of thyroid hormones due to their specific effects on different organs, maintaining the homeostasis among all tissues.
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BACKGROUND: Descending necrotizing mediastinitis is a dreadful disease with a high mortality rate, particularly when below the tracheal carina. This study describes the epidemiologic, clinical, and paraclinical features of patients treated for this condition. METHODS: We performed a single-center retrospective descriptive review of 60 patients with descending necrotizing mediastinitis below the tracheal carina, who were treated during a 7-year period, the largest study in the last 50 years. Demographic, clinical, paraclinical, and therapeutic variables were analyzed. RESULTS: 43 (71.7%) patients were male. The mean age was 41.2 ± 14.7 years. Mean hospital length of stay was 25.0 ± 19.8 days. Comorbidities were present in 46.7% of patients, diabetes mellitus being the most common. Odontogenic infections (45%) were the most frequent source of descending necrotizing mediastinitis. Cultures showed Gram-negative bacilli in 68.3%, Gram-positive cocci in 38.3%, and fungi in 6.7%. Mortality was 35% (21 patients); risk factors for mortality were age (>35 years), diabetes mellitus among other comorbidities, and associated complications. CONCLUSIONS: In this low socioeconomic status patient population, descending necrotizing mediastinitis below the carina causes high morbidity and mortality, the latter particularly associated with age, complications, diabetes mellitus and other comorbidities.