Síntesis y caracterización de un biomaterial para su uso en ingeniería de tejidos de piel

La ingeniería de tejidos constituye una disciplina relativamente nueva y un campo de investigación y desarrollo interdisciplinario que aplica los conocimientos de la bioingeniería, química, física, biología etc. para resolver problemas químicos y quirúrgicos asociados a la pérdida de tejido o al fallo funcional de órganos (San Román et al., 2000; Naderi et al., 2011). Esta área de conocimiento busca proporcionar una nueva solución a los problemas de daño o pérdida tisular, mediante el reemplazo o restauración de tejido. Más aún se aspira a recobrar la función de un órgano y en algunos casos su reconstrucción parcial o total, con estructuras que contengan poblaciones específicas de células. La meta fundamental de la ingeniería de tejidos es desarrollar sustitutos (biológicos o sintéticos) que restauren, mantengan o mejoren la función del tejido perdido o lesionado por trauma o enfermedad. (Marler et al., 1998; Landínez et al., 2010). Esta nueva área de estudio permitirá crear estrategias que permitan la sustitución del tejido dañado, por un tejido diseñado y construido para satisfacer las funciones y las necesidades de cada paciente

Preparation of quantum dots hydrogel nanocomposites with improved cytotoxicity

Nanocomposites are materials with unique properties and a wide range of applications. The combination of different nanostructures with traditional materials gives a variety of possibilities that should be analyzed. Especially, functional fluorescent semiconductor quantum dots (QDs) embedded in polymeric matrices have shown promising fluorescence and biocompatibility properties. These hybrid materials can be used in medical applications such as biodiagnostic and bioimaging. In this study, two hydrogels, one of polyethylene glycol diacrylate (PEGDA) and other of polyacrylamide (PAAm), were prepared with quantum dots of CdTe (4 nm of diameter) and characterized. The aim of this research was to analyze the optical properties of the nanocomposites and their cell viability. QDs nanocomposites were fabricated by a free radical polymerization process. The optical studies showed that the nanocomposites have well defined properties of fluorescence. To study the biocompatibility of the nanocomposites, metastatic B16f10 cell line were used and MTT assay was performed. The nanocomposites had a significant improved cell viability compared with QDs solutions

Decrease in Sperm Quality due to Infection of Human Papilloma Virus and Chlamydia trachomatis

Male infertility can have different causes, one of which may be the presence of etiologic agents that cause sexually transmitted infections. Among the most important sexually transmitted infections are human papillomavirus and Chlamydia trachomatis, which are as‐ sociated with infertility in females – whether they cause infertility in men is controversial. The purpose of the chapter is to review the effect of these two pathogens on male fertility, the evidence suggests that the most important infertility effect is linked to the condition of the sperm. However, it is noteworthy that there are few studies with respect to infertil‐ ity in regard to both pathogens, so it is important to further research this to elucidate the mechanisms by which these pathogens act on male infertility.UNIVERSIDAD AUTÓNOMA DEL ESTADO DE MÉXIC

Sustitutos de piel poliméricos para el tratamiento de úlcera en pie diabético

Diferentes complicaciones se pueden desarrollar en los pies de los pacientes diabéticos, entre las que se incluyen la neuropatía, la arteriopatía periférica, las infecciones, las ulceraciones y la gangrena. En especial las úlceras diabéticas son complicaciones crónicas que conllevan consecuencias graves en aspectos económicos (por ejemplo: altos costos hospitalarios) y de salud, además de tener un mal pronóstico. La úlcera diabética se puede definir desde diferentes perspectivas: clínica, biológica, evolutiva, entre otras, de forma simple se define como una lesión cutánea donde los procesos de cicatrización se encuentran alterados.Las úlceras diabéticas y la mala cicatrización son algunas de las complicaciones graves que pueden ocurrir después de una lesión en la piel en personas con diabetes mellitus. La ulceración en pie es la causa más frecuente de hospitalización, la cual puede llevar a la amputación hasta en un 85% de los casos a pesar de la atención médica. Por otra parte, la ulceración afecta del 12 al 25% en personas diagnosticadas con diabetes en algún momento de su vida, la cual representa una carga importante en términos monetarios para el sector salud. Por lo anterior la ingeniería de tejidos se dedica a desarrollar soluciones novedosas para combatir la perdida de tejido mediante el remplazo o restauración de la parte afectada. En el caso de la piel se han utilizado una gran variedad de biomateriales poliméricos que sirven como andamiajes para ayudar en los procesos de regeneración tisular, sin embargo todavía existe una creciente necesidad de materiales novedosos que asistan en los procesos biológicos de restablecimiento de la función del tejido u órgano dañado.En este trabajo se hace una revisión de aquellos materiales de origen polimérico actualmente en desarrollo para el tratamiento de la úlcera diabética y cierre de herid

Peripheral pathways in the food-intake control, towards the adipose-intestinal missing link.

In the physiological state a multitude of gut hormones are released into the circulation at the same time depending on the quality and quantity of the diet. These hormones interact with receptors at various points in the “gut-brain axis” to affect short-term and intermediate-term feelings of hunger and satiety. The combined effects of macronutrients on the predominant gut hormone secretion are still poorly understood. Besides, adipokines form an important part of an “adipoinsular axis” dysregulation which may contribute to -cell failure and hence to type 2 diabetes mellitus (T2DM). Even more, gestational diabetes mellitus (GDM) and T2DM seem to share a genetic basis. In susceptible individuals, chronic exaggerated stimulation of the proximal gut with fat and carbohydrates may induce overproduction of an unknown factor that causes impairment of incretin production and/or action, leading to insufficient or untimely production of insulin, so that glucose intolerance develops.The bypass of the duodenum and jejunum might avoid a putative hormone overproduction in the proximal foregut in diabetic patients that might counteract the action of insulin, while the early presentation of undigested or incompletely digested food to the ileum may anticipate the production of hormones such as GLP1, further improving insulin action

Mechanical Stimulation of Cells Through Scaffold Design for Tissue Engineering

Tissue engineering scaffolds attempt to mimic the stem cell environment by creating different biophysical and chemical signals. On the other hand, stem cells are able to sense these characteristics and change their destiny. Scientists try to explain these phenomena through scaffold design and in vitro experiments, but the mechanisms implicated remain unclear. Moreover, environment-cell interactions are a key process to get organs and tissues arrangement. Therefore, this chapter deals with the mechanical signals and mechanism involved in cell behaviour through scaffolds as a strategy in tissue engineering

Self-report prevalence and associated factors to drug hypersensitivity in Mexican young adults

Background: Drug hypersensitivity is defined as any unfavorable reaction that occurs after the administration of any drug. It may or may not be mediated by the involvement of the immune system. Epidemiological data related to drug hypersensitivity reactions in our country are scarce. Objective: To determine the prevalence of drug hypersensitivity in a group of young adults, as well as to identify associated factors. Methods: A structured questionnaire was applied to young people aged 18 to 25 years. The instrument was oriented to identify reactions of drug hypersensitivity, as well as the most prevalent drugs involved. In addition, a personal and family history of atopic diseases was included. Analysis for associations between variables was been done through logistic regression. Results: The prevalence of drug hypersensitivity reactions was 12% (144 of 1,200). The antibiotics were the agents most related to hypersensitivity reactions (9.8%) followed by nonsteroidal anti-inflammatory drugs (1.6%). Factors associated with drug hypersensitivity were a personal history of asthma, odds ratio (OR) 3.15 (95% confidence interval [CI], 1.44–6.91), maternal and paternal history of drug hypersensitivity, OR 2.33 (95% CI, 1.21–4.48) and OR 3.11 (95% CI, 1.22–7.92), respectively. Conclusion: The results of this research show that drug hypersensitivity in young adults is a highly prevalent event and it is associated with personal history of asthma and history of drug hypersensitivity in parents

Expression of AdipoR1 and AdipoR2 Receptors as Leptin-Breast Cancer regulation mechanisms

: La obesidad es considerada como uno de los principales factores de riesgo implicados en el desarrollo del cáncer de mama y se ha documentado el papel que juega el tejido adiposo a través de Leptina y Adiponectina. El estudio de estas proteínas ha determinado su importancia en el desarrollo y progreso del cáncer de mama, pero muy pocos son los que han estudiado a AdipoR1 y AdipoR2 y la influencia de la Leptina sobre ellos. Se planteó el analizó la expresión de AdipoR1 y AdipoR2 modulada por concentraciones diferenciales de Leptina en un modelo de obesidad asociado a cáncer de mama en líneas celulares, utilizando sondas TaqMan®, mediado por concentraciones diferenciales de Leptina en líneas celulares. Seguido se llevó a cabo la extracción de RNA, obtención de cDNA (Retrotranscripción) y PCR en tiempo real. Se caracterizó cada línea celular por medio de Inmunohistoquímica. Concluyendo con base en los resultados que la concentración de normo-peso (10ng/mL) de leptina generó un incremento de la expresión de ambos receptores de adiponectina.The development of breast cancer is influenced by the adipose tissue through the proteins leptin and adiponectin. However, there is little research concerning AdipoR1 and AdipoR2 receptors and the influence of leptin over them. The objective of this work was to analyze the expression of AdipoR1 and AdipoR2, modulated by differential concentrations of leptin in an obesity model (10ng/mL, 100ng/mL, and 1000ng/mL) associated with breast cancer in MCF-7 and HCC1937 cell lines. Each cell was characterized through immunohistochemistry, and the expression of AdipoR1 and AdipoR2 was analyzed by PCR in real time using TaqMan® probes. Leptin induced an increase in cell population of MCF-7 (23.8%, 10ng/m, 48 h) and HCC1937 (17.24%, 1000ng/mL, 72 h). In MCF-7, the expression of AdipoR1 decreased (3.81%, 1000ng/Ml) and the expression of AdipoR2 increased by 13.74 times (10ng/mL) with regard to the control. In HCC1937, the expression of AdipoR1 decreases by 86.28% (10ng/mL), as well as the expression of AdipoR1 and AdipoR2 mRNA

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements