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1.
Acta Physiol (Oxf) ; 240(9): e14203, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39023008

RESUMEN

AIM: The present study aimed to investigate the effects of a single bout of resistance exercise on mitophagy in human skeletal muscle (SkM). METHODS: Eight healthy men were recruited to complete an acute bout of one-leg resistance exercise. SkM biopsies were obtained one hour after exercise in the resting leg (Rest-leg) and the contracting leg (Ex-leg). Mitophagy was assessed using protein-related abundance, transmission electron microscopy (TEM), and fluorescence microscopy. RESULTS: Our results show that acute resistance exercise increased pro-fission protein phosphorylation (DRP1Ser616) and decreased mitophagy markers such as PARKIN and BNIP3L/NIX protein abundance in the Ex-leg. Additionally, mitochondrial complex IV decreased in the Ex-leg when compared to the Rest-leg. In the Ex-leg, TEM and immunofluorescence images showed mitochondrial cristae abnormalities, a mitochondrial fission phenotype, and increased mitophagosome-like structures in both subsarcolemmal and intermyofibrillar mitochondria. We also observed increased mitophagosome-like structures on the subsarcolemmal cleft and mitochondria in the extracellular space of SkM in the Ex-leg. We stimulated human primary myotubes with CCCP, which mimics mitophagy induction in the Ex-leg, and found that BNIP3L/NIX protein abundance decreased independently of lysosomal degradation. Finally, in another human cohort, we found a negative association between BNIP3L/NIX protein abundance with both mitophagosome-like structures and mitochondrial cristae density in the SkM. CONCLUSION: The findings suggest that a single bout of resistance exercise can initiate mitophagy, potentially involving mitochondrial ejection, in human skeletal muscle. BNIP3L/NIX is proposed as a sensitive marker for assessing mitophagy flux in SkM.


Asunto(s)
Mitofagia , Músculo Esquelético , Humanos , Mitofagia/fisiología , Masculino , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiología , Adulto , Mitocondrias Musculares/metabolismo , Mitocondrias Musculares/ultraestructura , Entrenamiento de Fuerza , Adulto Joven , Proteínas de la Membrana/metabolismo
2.
Polymers (Basel) ; 16(7)2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38611209

RESUMEN

Expanded polystyrene will account for 5.3% of total global plastic production in 2021 and is widely used for food packaging due to its excellent moisture resistance and thermal insulation. However, some of these packages are often used only once before being discarded, generating large amounts of environmentally harmful plastic waste. A very attractive alternative to the conventional methods used for polymer processing is the use of supercritical carbon dioxide (scCO2) since it has mass-transfer properties adapted to the foam morphology, generating different path lengths for the diffusion of active compounds within its structure and can dissolve a wide range of organic molecules under supercritical conditions. The objective of this research was to evaluate the effect of operational variables on the process of caffeic acid (CA) impregnation and subsequent foaming of polylactic acid (PLA) as well as two PLA/poly(butylene-co-terephthalate-adipate) (PBAT) blends using scCO2. The results showed an increase in the degree of crystallinity of the CA-impregnated samples due to the nucleation effect of the active compound. On the other hand, SEM micrographs of both films and foams showed significant differences due to the presence of PBAT and its low miscibility with PLA. Finally, the results obtained in this work contribute to the knowledge of the important parameters to consider for the implementation of the impregnation and foaming process of PLA and PLA/PBAT blends with potential use in food packaging.

3.
Cell Death Dis ; 13(7): 659, 2022 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-35902579

RESUMEN

Palmitic acid (PA) is significantly increased in the hypothalamus of mice, when fed chronically with a high-fat diet (HFD). PA impairs insulin signaling in hypothalamic neurons, by a mechanism dependent on autophagy, a process of lysosomal-mediated degradation of cytoplasmic material. In addition, previous work shows a crosstalk between autophagy and the primary cilium (hereafter cilium), an antenna-like structure on the cell surface that acts as a signaling platform for the cell. Ciliopathies, human diseases characterized by cilia dysfunction, manifest, type 2 diabetes, among other features, suggesting a role of the cilium in insulin signaling. Cilium depletion in hypothalamic pro-opiomelanocortin (POMC) neurons triggers obesity and insulin resistance in mice, the same phenotype as mice deficient in autophagy in POMC neurons. Here we investigated the effect of chronic consumption of HFD on cilia; and our results indicate that chronic feeding with HFD reduces the percentage of cilia in hypothalamic POMC neurons. This effect may be due to an increased amount of PA, as treatment with this saturated fatty acid in vitro reduces the percentage of ciliated cells and cilia length in hypothalamic neurons. Importantly, the same effect of cilia depletion was obtained following chemical and genetic inhibition of autophagy, indicating autophagy is required for ciliogenesis. We further demonstrate a role for the cilium in insulin sensitivity, as cilium loss in hypothalamic neuronal cells disrupts insulin signaling and insulin-dependent glucose uptake, an effect that correlates with the ciliary localization of the insulin receptor (IR). Consistently, increased percentage of ciliated hypothalamic neuronal cells promotes insulin signaling, even when cells are exposed to PA. Altogether, our results indicate that, in hypothalamic neurons, impairment of autophagy, either by PA exposure, chemical or genetic manipulation, cause cilia loss that impairs insulin sensitivity.


Asunto(s)
Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Animales , Autofagia , Cilios/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Hipotálamo/metabolismo , Insulina/metabolismo , Resistencia a la Insulina/genética , Ratones , Neuronas/metabolismo , Ácido Palmítico/metabolismo , Ácido Palmítico/farmacología , Proopiomelanocortina/metabolismo , Proopiomelanocortina/farmacología
4.
Biomedicines ; 9(11)2021 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-34829898

RESUMEN

Bacterial diseases and reactive oxygen species can cause dental caries and oral cancer. Therefore, the present review analyzes and discusses the antibacterial and antioxidant properties of synthetic and plant-derived substances and their current and future patents to formulate dental products. The reviewed evidence indicates that chlorhexidine, fluorides, and hydrogen peroxide have adverse effects on the sensory acceptability of oral care products. As an alternative, plant-derived substances have antimicrobial and antioxidant properties that can be used in their formulation. Also, adding plant metabolites favors the sensory acceptability of dental products compared with synthetic compounds. Therefore, plant-derived substances have antibacterial, antioxidant, and flavoring activity with the potential to be used in the formulation of toothpaste, mouth rinses, dentures cleansers-fixatives, and saliva substitutes.

5.
Chem Biodivers ; 18(7): e2100085, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34046999

RESUMEN

Neolentinus lepideus is a fungus consumed by rural communities in Central America and Asia due to its rich flavor; however, little information on its chemical composition is available. With this in mind, the objective of this work was to determine the content of vitamin E and C, ergosterol, and phenolic compounds of this fungus, as well as its antioxidant capacity. The quantified bioactive compounds were two isoforms of vitamin E, highlighting α-tocopherol (3370.35 mg/100 g dry weight, DW) and ergosterol (11.70 mg/100 g DW). The total phenolic content was 164.80 mg gallic acid equivalents/100 g, and nine phenolic compounds were identified (protocatechuic, p-hydroxybenzoic, caffeic, vanillic, ferulic, salicylic, p-anisic, trans-cinnamic acids, and scopoletin). The highest antioxidant capacity was detected in the lipophilic extract with TEAC (27688 µmoles Trolox equivalents/100 g). These results suggest that lipophilic compounds are among the main bioactive compounds in N. lepideus, and they might exhibit the highest radical scavenging properties in non-polar extracts.


Asunto(s)
Antioxidantes/farmacología , Basidiomycota/química , Cromanos/antagonistas & inhibidores , Antioxidantes/química , Antioxidantes/aislamiento & purificación
6.
Biomolecules ; 11(4)2021 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-33805256

RESUMEN

The objective of this study was to investigate structural changes and lignin redistribution in Eucalyptus globulus pre-treated by steam explosion under different degrees of severity (S0), in order to evaluate their effect on cellulose accessibility by enzymatic hydrolysis. Approximately 87.7% to 98.5% of original glucans were retained in the pre-treated material. Glucose yields after the enzymatic hydrolysis of pre-treated material improved from 19.4% to 85.1% when S0 was increased from 8.53 to 10.42. One of the main reasons for the increase in glucose yield was the redistribution of lignin as micro-particles were deposited on the surface and interior of the fibre cell wall. This information was confirmed by laser scanning confocal fluorescence and FT-IR imaging; these microscopic techniques show changes in the physical and chemical characteristics of pre-treated fibres. In addition, the results allowed the construction of an explanatory model for microscale understanding of the enzymatic accessibility mechanism in the pre-treated lignocellulose.


Asunto(s)
Eucalyptus/metabolismo , Lignina/metabolismo , Celulasa/metabolismo , Hidrólisis , Lignina/química , Microscopía Confocal , Análisis de Componente Principal , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
7.
Polymers (Basel) ; 13(7)2021 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-33805582

RESUMEN

Organoclay nanoparticles (Cloisite® C10A, Cloisite® C15) and their combination with carbon black (N330) were studied as fillers in chloroprene/natural/butadiene rubber blends to prepare nanocomposites. The effect of filler type and load on the physical mechanical properties of nanocomposites was determined and correlated with its structure, compatibility and cure properties using Fourier Transformed Infrared (FT-IR), X-ray Diffraction (XRD), Thermogravimetric Analysis (TGA) and rheometric analysis. Physical mechanical properties were improved by organoclays at 5-7 phr. Nanocomposites with organoclays exhibited a remarkable increase up to 46% in abrasion resistance. The improvement in properties was attributed to good organoclay dispersion in the rubber matrix and to the compatibility between them and the chloroprene rubber. Carbon black at a 40 phr load was not the optimal concentration to interact with organoclays. The present study confirmed that organoclays can be a reinforcing filler for high performance applications in rubber nanocomposites.

8.
Sci Rep ; 10(1): 21154, 2020 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-33273645

RESUMEN

Obesity has been firmly established as a major risk factor for common disease states including hypertension, type 2 diabetes mellitus, and chronic kidney disease. Increased body mass index (BMI) contributes to the activation of both the systemic and intra-tubular renin angiotensin systems (RAS), which are in turn associated with increased blood pressure (BP) and kidney damage. In this cross-sectional study, 43 subjects of normal or increased body weight were examined in order to determine the correlation of BMI or body fat mass (BFM) with blood pressure, fasting blood glucose (FBG), and urinary kidney injury markers such as interleukin-18 (IL-18), connective tissue growth factor (CTGF), neutrophil gelatinase-associated lipocalin, and kidney injury molecule-1 (KIM-1). Our results showed that: (1) subjects with increased body weight showed significantly higher BP, BFM, total body water and metabolic age; (2) BMI was positively correlated to both systolic (R2 = 0.1384, P = 0.01) and diastolic BP (R2 = 0.2437, P = 0.0008); (3) BFM was positively correlated to DBP (R2 = 0.1232, P = 0.02) and partially correlated to urine protein (R2 = 0.047, P = 0.12) and FBG (R2 = 0.07, P = 0.06); (4) overweight young adults had higher urinary mRNA levels of renin, angiotensinogen, IL-18 and CTGF. These suggest that BMI directly affects BP, kidney injury markers, and the activation of the intra-tubular RAS even in normotensive young adults. Given that BMI measurements and urine analyses are non-invasive, our findings may pave the way to developing a new and simple method of screening for the risk of chronic kidney disease in adults.


Asunto(s)
Biomarcadores/orina , Riñón/lesiones , Riñón/metabolismo , Sobrepeso/genética , Sobrepeso/orina , Sistema Renina-Angiotensina/genética , Tejido Adiposo , Adiposidad , Adolescente , Angiotensinógeno/metabolismo , Glucemia/metabolismo , Presión Sanguínea , Índice de Masa Corporal , Factor de Crecimiento del Tejido Conjuntivo/genética , Factor de Crecimiento del Tejido Conjuntivo/orina , Ayuno/sangre , Femenino , Humanos , Interleucina-18/genética , Interleucina-18/orina , Riñón/fisiopatología , Modelos Lineales , Masculino , ARN Mensajero/genética , ARN Mensajero/metabolismo , Renina/metabolismo , Adulto Joven
9.
Mol Cell Oncol ; 7(5): 1789418, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32944643

RESUMEN

High-fat diet (HFD)-induced obesity is associated with increased cancer risk. Long-term feeding with HFD increases the concentration of the saturated fatty acid palmitic acid (PA) in the hypothalamus. We previously showed that, in hypothalamic neuronal cells, exposure to PA inhibits the autophagic flux, which is the whole autophagic process from the synthesis of the autophagosomes, up to their lysosomal fusion and degradation. However, the mechanism by which PA impairs autophagy in hypothalamic neurons remains unknown. Here, we show that PA-mediated reduction of the autophagic flux is not caused by lysosomal dysfunction, as PA treatment does not impair lysosomal pH or the activity of cathepsin B.Instead, PA dysregulates autophagy by reducing autophagosome-lysosome fusion, which correlates with the swelling of endolysosomal compartments that show areduction in their dynamics. Finally, because lysosomes undergo constant dynamic regulation by the small Rab7 GTPase, we investigated the effect of PA treatment on its activity. Interestingly, we found PA treatment altered the activity of Rab7. Altogether, these results unveil the cellular process by which PA exposure impairs the autophagic flux. As impaired autophagy in hypothalamic neurons promotes obesity, and balanced autophagy is required to inhibit malignant transformation, this could affect tumor initiation, progression, and/or response to therapy of obesity-related cancers.

10.
Rev. cuba. salud pública ; Rev. cuba. salud pública;45(3): e1628, jul.-sep. 2019. tab, graf
Artículo en Español | LILACS, CUMED | ID: biblio-1058441

RESUMEN

Introducción: La evaluación de un programa odontológico debe considerar, además de los resultados clínicos, la percepción del paciente en relación a cambios físicos, psicológicos y sociales. En este contexto, la calidad de vida relacionada con salud oral constituye un importante indicador de impacto sanitario y de eficacia de un tratamiento. Objetivo: Evaluar el impacto de la salud oral en la calidad de vida de mujeres que recibieron intervención odontológica en centros de atención primaria de salud de la Región de los Ríos, Chile. Métodos: Estudio cuasi experimental con diseño antes-después de una intervención odontológica en 3907 mujeres, de 15 o más años, en condición de vulnerabilidad con problemas dentales que afectan su calidad de vida relacionada con su salud oral. Se midió a través del cuestionario Perfil de Impacto en Salud Oral (OHIP-7sp). Resultados: Se obtuvo una muestra representativa del 5 por ciento de las participantes (n =137), edad media 48,1 ± 16,1 años. Un 96,4 por ciento percibió que la salud bucal afecta su calidad de vida, valor que desciende a 51,8 por ciento después de la intervención. La variación porcentual fue de 46,3 por ciento. Se evidenció la relación entre calidad de vida y la edad de las participantes. Conclusión: la intervención odontológica tiene un impacto positivo en la calidad de vida relacionada con salud oral de las mujeres, e indirectamente ayuda a mejorar la empleabilidad, porque contribuye, con una mejor salud oral, a fortalecer su autoestima y sus relaciones sociales(AU)


Introduction: The assessment of a dental program should consider, in addition to the clinical results, the perception of the patient in relation to physical, psychological and social changes. In this context, quality of life related to oral health is an important indicator of the health impact and efficacy of a treatment. Objective: To assess the impact of oral health in the quality of life of women who received a dental intervention in primary healthcare centers in the Region of Los Ríos, Chile. Methods: Quasi-experimental study with a before-after design of a dental intervention in 3,907 women aged 15 years or more in vulnerable conditions with dental problems that affect their life quality related to oral health. It was measured by means of the questionnaire Profile of Impact in Oral Health (OHIP-7sp) with previous informed consent, before and after the dental intervention. Results: A representative sample of 5 percent of the participants (n = 137), average age 48.1 ± 16.1 years was obtained. 96,4 percent perceived that oral health affects their quality of life, a value that drops to 51,8 percent after the intervention. The percentage variation was of 46,3 percent being a positive result indicator of program evaluation. It was evidenced a relationship between life quality and the age of the participants. Conclusion: The odontological intervention has a positive impact in quality of life related to women's oral health, and indirectly meets with improving the employability of the beneficiaries by contributing to better oral health, strengthening their self-esteem and social relationships(AU)


Asunto(s)
Humanos , Femenino , Calidad de Vida , Grupos de Riesgo , Salud Bucal , Salud de la Mujer , Chile
11.
Rev. enferm. neurol ; 17(2): 33-41, may-ago 2018.
Artículo en Español | LILACS, BDENF - Enfermería | ID: biblio-1047130

RESUMEN

Introducción: la familia es el grupo fundamental para incrementar el estado de salud de los adultos mayores, ya que promueve el bienestar y el desarrollo psicoemocional en los cuales la depresión es considerada como problema de salud pública pues involucra no sólo la intervención familiar sino también la del sector salud. Objetivo: determinar la relación que existe entre depresión y funcionalidad familiar en el adulto mayor que acude a una unidad de salud de segundo nivel de atención en Ciudad Victoria, Tamaulipas, México. Material y métodos: estudiocuantitativo, descriptivo-transversal y correlacional realizado con 139 adultos mayores en una institución de salud de la localidad mediante muestreo probabilístico aleatorio simple, a través de entrevista y aplicación del Apgar familiar y escala de Yesavage. Los datos se analizaron mediante el programa SPSS v.22 a través de estadística descriptiva e inferencial. Resultados: edad promedio 68.14 años, predominio femenino 63%, con escolaridad pri-maria 87%; 80% con ausencia de sintomatología depresiva, 81% bajo un entorno familiar normofuncional. Conclusión: si existe relación entre ambas variables (p= 0.01).


Asunto(s)
Humanos , Depresión , Anciano , Salud Pública
12.
Bot Stud ; 58(1): 12, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28510195

RESUMEN

BACKGROUND: The anatomical traits associated with water deficit are also observed in plants growing in poor soils. The species may resist water deficit through three main strategies: escape, avoid or tolerate. The Pedregal de San Ángel Ecological Reserve (REPSA), Mexico, is an environment with low nutrient soil and low water availability. It is set on the basalt formation derived from the Xitle volcano eruption. The main vegetation type is characterized as xerophytic shrub. Thus we expect that species growing in this community will show leaf xeromorphic traits and may have any of the three response strategies. We analyzed the foliar anatomy of 52 species of the Asteraceae family at the REPSA because it is the most abundant angiosperm family in the site, showing a wide variety of growth forms and anatomical variation. RESULTS: The foliar anatomies of the studied Asteraceae were highly variable as well as their quantitative traits as revealed by principal component analysis. This agrees with previous studies that found great anatomical variation within the family. Leaves have multiple layered palisade parenchyma and parenchyma bundle sheaths and could not be categorized as xeromorphic because they possess mesomorphic leaf features as simple lamina, single-layered epidermis, and soft large-size glabrous leaves with high specific leaf area. CONCLUSIONS: The combination of mesomorphic and few xeromorphic foliar traits with other characters at the genus and tribal level probably has been essential in Asteraceae to colonize various environments, including those with low water and nutrient availability.

13.
Artículo en Español | LILACS, MOSAICO - Salud integrativa | ID: biblio-910899

RESUMEN

Este trabajo aborda la importancia de prevenir el uso indiscriminado de productos naturales o macrobióticos, sus posibles efectos perjudiciales en la salud, así concienciar a profesionales en el área de la salud sobre la importancia de incluir este tema durante la historia médica. Se analiza el incremento en el uso de productos naturales o macrobióticos, las ventajas de la etnomedicina como un resurgimiento de la industria farmacéutica y las desventajas que acarrea este tipo de productos. Las hierbas ofrecen una alternativa terapéutica como la creación de nuevos fármacos, aunque poseen efectos secundarios que podrían arriesgar la salud de los pacientes.


Asunto(s)
Humanos , Plantas Medicinales , Productos Biológicos , Medicina Tradicional , Salud Pública , Ginkgo biloba , Costa Rica
14.
CES odontol ; 29(1): 5-12, ene.-jun. 2016. ilus, tab
Artículo en Español | LILACS | ID: biblio-828360

RESUMEN

Introducción: En adultos mayores la percepción de calidad de vida relacionada con salud bucal (CVRSB) toma particular importancia por el deterioro acumulado y falta de acciones de salud priorizadas en ellos. A pesar de los resultados en grupos específicos, no hay estudios nacionales que refieran diferencias de esta percepción entre comunas Objetivo: Comparar la CVRSB de adultos mayores, que asisten a centros de atención primaria de salud en las comunas de Puerto Saavedra y Vitacura. Materiales y métodos: Se realizó un estudio de corte transversal a 270 adultos mayores de ambos sexos, 57 de Puerto Saavedra y 213 de Vitacura. Se utilizó el cuestionario Geriatric Oral Health Assesment index (GOHAI) para medir CVRSB. Se realizó análisis descriptivo univariado y bivariado de los datos, contrastando hipótesis con prueba-T, Exacto de Fisher o Mann-Whitney según la naturaleza de las variables, se utilizó Stata 13.0. Resultados: Un 77,4% percibió su CVRSB como negativa. La media de los puntajes del GOHAI fueron similares en ambas comunas, con valores más bajos de percepción en la comuna de Puerto Saavedra; la diferencia no fue significativa estadísticamente (p>0,05). Se observó una tendencia negativa en los puntajes para el sexo femenino en ambas comunas. Conclusiones: La CVRSB es percibida negativamente, independiente de la edad y comuna de residencia. Situación coherente con un escenario nacional de alta carga de enfermedades bucales y limitado acceso a atención dental, agravado en adultos mayores debido al daño acumulado desarrollado y la desprotección histórica en salud dental.


Introduction: In the elderly oral health-related quality of life (OHRQoL) perception is particularly important because of the accumulated impairment and lack of prioritized health actions for them. Despite group-specific results there is no national study that refers differences between districts. Objetive: To compare the perception of OHRQoL in the elderly who attend to primary health care in Puerto Saavedra and Vitacura. Materials and methods: A cross-sectional study was performed to 270 older adults of both sexes, 57 from Puerto Saavedra and 213 from Vitacura. Geriatric oral health asessment index (GOHAI) was used to measure OHRQoL. Descriptive univariate and bivariate analyses was perfomed. Contrast hypothesis tests were selected according to the nature of the variables and statistical analyses was performed in Stata13.0. Results: 77.4% perceived their OHRQoL as negative. Mean GOHAI score were similar in both districts. Puerto Saavedra showed lower scores, the difference was not statistically significative (p>0.05). Negative tendency was observed in females groups for both districts. Conclusions: OHRQoL is perceived as negative regardless of age and residence districts. This is coherent with the national scenery of high burden of oral disease and limited access to oral-health care wich is aggravated in older adults due to accumulated damage and historical absence of protection in oral health.

15.
Rev. bioméd. (México) ; 27(1): 31-41, ene.-abr. 2016. graf
Artículo en Español | LILACS | ID: biblio-1041919

RESUMEN

Resumen Serendipia, una palabra común en la literatura científica en inglés; pero que luego de casi 300 años de su acuñación no ha sido aceptada por la Real Academia Española. En todo caso, se refiere a los descubrimientos realizados por accidente, casualidad o hechos fortuitos, pero siempre detrás de una mente acuciosa, capaz de comprender, explicar y aplicar, eso que algunos llaman accidentes afortunados, que incluyen desde la ley de la gravedad, la invención de la máquina de vapor y muchos otros inventos, incluyendo descubrimientos de uso cotidiano en la odontología. En esta última rama de las ciencias biológicas, se recopila información referente al estetoscopio, la anestesia, los rayos x, la penicilina y los implantes dentales, todos producto de la serendipia.


Abstract Serendipity is an usual word in the English scientific literature; but after almost 300 years the word still is not accepted by the Real Academia Española. However, it means the discovery by accident, chance or fortuity but always behind a diligent mind, capable of comprehend, explain and apply those fortuity accidents, such as the gravity discover, the invention of the vapor machine and others more, including some inventions of daily use in dentistry. In this branch of biological science, we collect information about the stethoscope, anesthesia, x-rays, penicillin and dental implants all of them have occurred by serendipity.

16.
Microbiology (Reading) ; 162(6): 979-988, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27010660

RESUMEN

In Sinorhizobium meliloti, nitrogen fixation is regulated in response to oxygen concentration through the FixL-FixJ two-component system (TCS). Besides this conserved TCS, the field isolate SM11 also encodes the hFixL-FxkR TCS, which is responsible for the microoxic response in Rhizobium etli. Through genetic and physiological assays, we evaluated the role of the hFixL-FxkR TCS in S. meliloti SM11. Our results revealed that this regulatory system activates the expression of a fixKf orthologue (fixKa), in response to low oxygen concentration. Null mutations in either hFixL or FxkR promote upregulation of fixK1, a direct target of FixJ. Furthermore, the absence of this TCS translates into higher nitrogen fixation values as well as higher expression of fixN1 in nodules. Individual mutations in each of the fixK-like regulators encoded in the S. meliloti SM11 genome do not completely restrict fixN1 or fixN2 expression, pointing towards redundancy among these regulators. Both copies of fixN are necessary to achieve optimal levels of nitrogen fixation. This work provides evidence that the hFixL-FxkR TCS is activated in response to low oxygen concentration in S. meliloti SM11 and that it negatively regulates the expression of fixK1, fixN1 and nitrogen fixation.


Asunto(s)
Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/genética , Hemoproteínas/genética , Medicago sativa/microbiología , Proteínas de la Membrana/biosíntesis , Fijación del Nitrógeno/genética , Nódulos de las Raíces de las Plantas/metabolismo , Sinorhizobium meliloti/genética , Sinorhizobium meliloti/metabolismo , Anaerobiosis/fisiología , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica/genética , Hemoproteínas/metabolismo , Histidina Quinasa , Leghemoglobina/metabolismo , Proteínas de la Membrana/metabolismo , Oxígeno/metabolismo , Plásmidos/genética , Nódulos de las Raíces de las Plantas/microbiología , Sinorhizobium meliloti/aislamiento & purificación
17.
Rev. chil. nutr ; 42(4): 369-373, dic. 2015. tab
Artículo en Inglés | LILACS | ID: lil-775508

RESUMEN

Objective: The aim of this study was to compare the risk of Eating Disorders Behaviour (EDB), and its anthropometric profile, physical activity and alimentary intake between Mexican fashion models (FM) and control women Methods: We included 50 FM and 50 control women, of the same social group, all over 18 years old, from Guadalajara, Mexico, matched by age. We evaluated the risk of EDB with the Eating Attitudes Test (EAT-26); the anthropometric measures were taken according to the criteria of the International Society for the Advancement of Kinanthropometry (ISAK), 24-hour recall to estimate energy intake and physical activities. Results: The risk prevalence of EDB was 10% for both groups. The mean and standard deviation of the percentage of body fat in FM was 22,4±2, lower than in the controls (27,8±4, p<0.001). There were no differences in anthropometric measurements in women with and without risk of EDB, except in the weight (FM without risk of EDB 56,3±3 kg and 59,9±3 kg with risk of EDB (p<0.02). Caloric intake in women with risk of EDB reduced was 1094±208 kcal in FM versus 1269±435 kcal in control woman. Conclusion: The anthropometric measurements, alimentary intake and previous history of eating disorders, suggests that FM of Mexico are a vulnerable population for eating disorder.


Objetivo: Comparar el riesgo de trastornos de la conducta alimentaria (TCA), perfil antropométrico, actividad física e ingesta alimentaria entre las mujeres mexicanas dedicadas al modelaje profesional (MP) con mujeres control. Métodos: Se incluyeron 50 MP y 50 mujeres controles, del mismo grupo social, mayores de 18 años, de Guadalajara, México, pareadas por edad. Se evaluó el riesgo de TCA con el test de Trastornos de Actitudes Alimentarias (EAT-26), se tomaron las medidas antropométricas de acuerdo a los criterios de la International Society for the Advancement of Kinanthropometry (ISAK). Se estimó el consumo de energía utilizando el recordatorio de 24 horas y se registró la práctica de actividades físicas. Resultados: La prevalencia de riesgo de TCA fue 10% para ambos grupos. La media y desviación estándar del porcentaje de grasa corporal en las MP fue 22,4±2,5 menor al de las controles (27,8±4,9) (p<0.001). No hubo diferencias en la medidas antropométricas en las mujeres con y sin riesgo de TCA, excepto en el peso de las MP de 56,3±3,1 kg sin riesgo de TCA y 59,9±3,6 en las con riesgo de TCA (p<0.02). La ingesta alimentaria se encontró reducida en las mujeres con riesgo de TCA con respecto a las sin riesgo, con 1094,2±208,3 kcal versus 1269,8±435,0 kcal en las MP y controles respectivamente. Conclusión: Las medidas antropométricas, la ingesta alimentaria y la historia previa de trastornos de la alimentación, sugiere que la MP de México es una población vulnerable para trastornos de la alimentación.


Asunto(s)
Humanos , Mujeres Trabajadoras , Ingestión de Energía , Anorexia Nerviosa , Trastornos de Alimentación y de la Ingestión de Alimentos , Índice de Masa Corporal , Bulimia Nerviosa , Estado Nutricional , Medición de Riesgo
18.
Rev Salud Publica (Bogota) ; 17(1): 132-9, 2015.
Artículo en Español | MEDLINE | ID: mdl-26437707

RESUMEN

In the context of the great diversity of oral microflora, including over 600 species, we highlight the educational value of electron micrographs and images of dental plaque cultures in dental models made with culture media, showing the bacterial colonies in the anatomic sites of the teeth that were most abundantly colonized. Such images allow for an easy understanding of the magnitude of the oral microbiome for students of biomedical careers--especially dentistry--and for the general public. As such, these images can be used in teaching programs and oral health campaigns.


Asunto(s)
Biopelículas , Placa Dental/microbiología , Promoción de la Salud , Microbiota , Microscopía Electrónica de Transmisión , Salud Bucal/educación , Humanos
19.
Rev. salud pública ; Rev. salud pública;17(1): 1-1, ene.-jun. 2015. ilus, tab
Artículo en Español | LILACS | ID: lil-755629

RESUMEN

En el contexto de la gran diversidad de la microflora oral, con más de 600 especies, se resalta el valor pedagógico de las micrografías electrónicas de placa alba y las imágenes de cultivos bacterianos, realizados en modelos dentales hechos con medios de cultivo, que muestran colonias bacterianas en los sitios anatómicos de los dientes colonizados más abundantemente. Este tipo de imágenes facilita la comprensión de la magnitud del microbioma oral, a estudiantes de carreras biomédicas, especialmente odontología y al público en general, por lo que el uso de estas imágenes pueden ser utilizadas en docencia como en campañas de salud oral.


In the context of the great diversity of oral microflora, including over 600 species, we highlight the educational value of electron micrographs and images of dental plaque cultures in dental models made with culture media, showing the bacterial colonies in the anatomic sites of the teeth that were most abundantly colonized. Such images allow for an easy understanding of the magnitude of the oral microbiome for students of biomedical careers -especially dentistry- and for the general public. As such, these images can be used in teaching programs and oral health campaigns.


Asunto(s)
Humanos , Biopelículas , Placa Dental/microbiología , Promoción de la Salud , Microbiota , Microscopía Electrónica de Transmisión , Salud Bucal/educación
20.
Bol. méd. Hosp. Infant. Méx ; 70(2): 89-97, may.-abr. 2013. ilus, tab
Artículo en Español | LILACS | ID: lil-701228

RESUMEN

Introducción. La sordera congénita es un problema de salud pública. Su incidencia en México es de 2-3 por cada 1000 recién nacidos. El diagnóstico oportuno con el tamiz auditivo neonatal es fundamental para un mejor pronóstico funcional. Aproximadamente 70% de las sorderas congénitas son de origen genético, con herencia autosómica recesiva. La mayoría de estos casos se asocia con mutaciones en el gen GJB2 , que codifica para la proteína conexina 26. Hay tres mutaciones reportadas como las más frecuentes en este gen: c.35delG, c.167delT y c.235delC. Métodos. Previo consentimiento informado de los pacientes, se obtuvo 1 ml de sangre periférica para la extracción de ADN. Mediante las técnicas de PCR-RFLP o PCR seguida de secuenciación, se buscaron las tres mutaciones más frecuentes del gen GJB2 . Resultados. Se realizó el estudio molecular en 11 pacientes: Se encontró un cambio en la secuencia codificante en cinco de ellos. Un paciente fue homocigoto para c.35delG; otro resultó heterocigoto para c.35insG, mutación no reportada previamente; un tercero fue heterocigoto para c.34G>T y dos más fueron heterocigotos para el polimorfismo c.79G>A (p.V27I). En ningún caso se hallaron las mutaciones c.167delT y c.235delC. Conclusiones. Se encontraron cambios de secuencias que correspondieron a dos polimorfismos y a tres mutaciones. La frecuencia de las tres mutaciones investigadas fue menor a lo reportado en la literatura y se encontró una mutación no reportada previamente. Este estudio evidencia la importancia del diagnóstico oportuno con manejo integral, incluyendo el asesoramiento genético con base en estudios moleculares, y resalta la importancia de conocer el perfil genotípico de este grupo de pacientes.


Background. Congenital deafness is a public health problem affecting 2-3:1000 newborns in Mexico. Neonatal audiologic screening allows early detection with important implications for the functional prognosis. About 70% of cases of congenital deafness are associated with a genetic etiology with an autosomal recessive pattern of inheritance. Most cases are caused by mutations in the GJB2 gene, which codifies conexin 26. The three most commonly reported mutations in this gene are c.35delG, c.167delT and c.235delC. Methods. After obtaining informed consent, DNA was extracted from a blood sample, and the three previously mentioned mutations were searched for using PCR-RFLP or PCR followed by sequencing. Results. Molecular analysis was carried out in 11 patients. In five of these patients, a change in sequence was observed. In none of the patients were c.167delT and c.235delC mutations found. One patient was homozygous for c.35delG and another patient was heterozygous for c.35insG, which is a mutation not previously reported. A third patient was heterozygous for c.34G>T. Two additional patients had the c.79G>A (p.V27I) polymorphism. Conclusions. Frequency of the three mutations analyzed was lower compared to other populations. Five sequence changes were observed, two polymorphisms and three mutations, one of them novel. This study also demonstrates the relevance of early diagnosis and multidisciplinary management and the importance of determining the genetic basis of this disease in pediatric patients with congenital deafness.

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