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1.
Sol Phys ; 299(2): 23, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38390515

RESUMEN

The Mancha3D code is a versatile tool for numerical simulations of magnetohydrodynamic (MHD) processes in solar/stellar atmospheres. The code includes nonideal physics derived from plasma partial ionization, a realistic equation of state and radiative transfer, which allows performing high-quality realistic simulations of magnetoconvection, as well as idealized simulations of particular processes, such as wave propagation, instabilities or energetic events. The paper summarizes the equations and methods used in the Mancha3D (Multifluid (-purpose -physics -dimensional) Advanced Non-ideal MHD Code for High resolution simulations in Astrophysics 3D) code. It also describes its numerical stability and parallel performance and efficiency. The code is based on a finite difference discretization and a memory-saving Runge-Kutta (RK) scheme. It handles nonideal effects through super-time-stepping and Hall diffusion schemes, and takes into account thermal conduction by solving an additional hyperbolic equation for the heat flux. The code is easily configurable to perform different kinds of simulations. Several examples of the code usage are given. It is demonstrated that splitting variables into equilibrium and perturbation parts is essential for simulations of wave propagation in a static background. A perfectly matched layer (PML) boundary condition built into the code greatly facilitates a nonreflective open boundary implementation. Spatial filtering is an important numerical remedy to eliminate grid-size perturbations enhancing the code stability. Parallel performance analysis reveals that the code is strongly memory bound, which is a natural consequence of the numerical techniques used, such as split variables and PML boundary conditions. Both strong and weak scalings show adequate performance up to several thousands of processors (CPUs).

2.
J Endocrinol Invest ; 47(3): 571-583, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37624484

RESUMEN

PURPOSE: A variable number of tandem repeats (VNTR) in the insulin gene (INS) control region may be involved in type 2 diabetes (T2D). The TH01 microsatellite is near INS and may regulate it. We investigated whether the TH01 microsatellite and INS VNTR, assessed via the surrogate marker single nucleotide polymorphism rs689, are associated with T2D and serum insulin levels in a Mexican population. METHODS: We analyzed a main case-control study (n = 1986) that used univariate and multivariate logistic regression models to calculate the risk conferred by TH01 and rs689 loci for T2D development; rs689 results were replicated in other case-control (n = 1188) and cross-sectional (n = 1914) studies. RESULTS: TH01 alleles 6, 8, 9, and 9.3 and allele A of rs689 were independently associated with T2D, with differences between sex and age at diagnosis. TH01 alleles with ≥ 8 repeats conferred an increased risk for T2D in males compared with ≤ 7 repeats (odds ratio, ≥ 1.46; 95% confidence interval, 1.1-1.95). In females, larger alleles conferred a 1.5-fold higher risk for T2D when diagnosed ≥ 46 years but conferred protection when diagnosed ≤ 45 years. Similarly, rs689 allele A was associated with T2D in these groups. In males, larger TH01 alleles and the rs689 A allele were associated with a significant decrease in median fasting plasma insulin concentration with age in T2D cases; the reverse occurred in controls. CONCLUSION: Larger TH01 alleles and rs689 A allele may potentiate insulin synthesis in males without T2D, a process disabled in those with T2D.


Asunto(s)
Diabetes Mellitus Tipo 2 , Tirosina 3-Monooxigenasa , Femenino , Masculino , Humanos , Secreción de Insulina , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/genética , Repeticiones de Minisatélite , Estudios de Casos y Controles , Estudios Transversales , Ayuno , Insulina , Repeticiones de Microsatélite/genética
3.
Rev Med Chil ; 150(5): 611-617, 2022 May.
Artículo en Español | MEDLINE | ID: mdl-37906761

RESUMEN

BACKGROUND: Telemedicine became a relevant means to provide healthcare without face-to-face medical evaluation during the COVID-19 pandemic. AIM: To describe the effectiveness of telemedicine in vascular surgery. MATERIALS AND METHODS: Review of medical records of all vascular surgery consultations carried out in a clinical hospital between April and October 2020. The main outcome measured was the resolution of the reason for consultation. Secondary outcomes were the need to request laboratory tests or imaging, the need to evaluate the patient in person, and the need for referral to hospitalization or emergency service. RESULTS: One hundred-six new consultations and their follow-up (remotely or in person) were analyzed. A definitive diagnosis could be reached in 74% of consultations, treatment could be instituted or modified in 69% of them, and the reason for consultation could be resolved in 74% of cases. Laboratory and imaging tests were requested in 36 and 63% of consultations, respectively. Four percent of patients were referred to the emergency department or hospitalization. CONCLUSIONS: In the vast majority of consultations, it was possible to achieve a definitive diagnosis, prescribe a treatment and resolve the reason for consultation without the need for a face-to-face medical evaluation.


Asunto(s)
COVID-19 , Telemedicina , Humanos , Pandemias , Derivación y Consulta , Procedimientos Quirúrgicos Vasculares
4.
Enferm Intensiva ; 33(4): 185-196, 2022.
Artículo en Español | MEDLINE | ID: mdl-34898979

RESUMEN

Introduction: Current healthcare settings and ICUs especially are complex, highly technical, and multidisciplinary, with interactions between healthcare professionals and users, in which there may be errors at different levels. Our objective was to assess the perception of patient safety in our unit at the end of the third wave of the COVID pandemic, with the intention of conducting subsequent improvement actions. Methods: Observational, cross-sectional, and descriptive study. The perception of Safety Culture was estimated using the HSOPS questionnaire translated into Spanish. Some questions were posed in a positive sense, and others in a negative sense. The response was also rated as positive, negative, or neutral. Our findings were compared visually, not mathematically, with those found in the previous national study «Analysis of the culture on patient safety in the hospital setting of the Spanish National Health System¼ published in 2009. A subgroup analysis was performed according to professional group and seniority as a health worker. The Student's t, χ? and ANOVA tests were used. Results: Sixty-two professionals responded to the questionnaire, 73.90% of the total. The median time working in ICU 2 years (interquartile range 2-4.5 years). The rating for the degree of safety was 8.06 (SD 1.16). The majority (91.20%) had not reported any adverse event in the last year. A total of 30.90% had recently received patient safety training. The dimensions considered as weaknesses were 9 («Staffing¼, with 27.57% of positive responses) and 10 ("Support of the hospital management in safety", with 17.64% of positive responses). The dimensions considered as strengths were 3 («Expectation of actions by management / supervision of the service¼) with 85.29% of positive responses, and 5 («Teamwork¼) with 95.58% of positive responses. The Cronbach's alpha index values suggest that the questionnaire has adequate internal consistency. In general, our data are more positive than those collected in the 2011 national survey, although the 2 dimensions considered weaknesses were already considered such in the previous work. Conclusions: The perception of patient safety in the ICU of our hospital after the end of the third wave of the COVID pandemic is adequate, with a more positive rating than that of the national study on safety culture at the hospital level carried out in 2009. The constant quest for patient safety should prioritize activity in the 2 dimensions considered weaknesses: staffing, and support from hospital management in everything related to patient safety.

5.
Philos Trans A Math Phys Eng Sci ; 379(2190): 20200176, 2021 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-33342386

RESUMEN

This paper presents the results of the analysis of three-dimensional simulations of solar magneto-convection that include the joint action of the ambipolar diffusion and the Hall effect. Three simulation runs are compared: one including both ambipolar diffusion and the Hall effect; one including only ambipolar diffusion and one without any of these two effects. The magnetic field is amplified from initial field to saturation level by the action of turbulent local dynamo. In each of these cases, we study 2 h of simulated solar time after the local dynamo reaches the saturation regime. We analyse the power spectra of vorticity, of magnetic field fluctuations and of the different components of the magnetic Poynting flux responsible for the transport of vertical or horizontal perturbations. Our preliminary results show that the ambipolar diffusion produces a strong reduction of vorticity in the upper chromospheric layers and that it dissipates the vortical perturbations converting them into thermal energy. The Hall effect acts in the opposite way, strongly enhancing the vorticity. When the Hall effect is included, the magnetic field in the simulations becomes, on average, more vertical and long-lived flux tube-like structures are produced. We trace a single magnetic structure to study its evolution pattern and the magnetic field intensification, and their possible relation to the Hall effect. This article is part of the Theo Murphy meeting issue 'High-resolution wave dynamics in the lower solar atmosphere'.

6.
J Endocrinol Invest ; 42(10): 1231-1240, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30953318

RESUMEN

PURPOSE: In recent years, an increasing number of specialized gender clinics have been prescribing gonadotropin-releasing hormone (GnRH) analogs to adolescents diagnosed with gender dysphoria (GD) to suppress puberty. This paper presents qualitative research on the hormone therapy (HT) experiences of older trans-people and their views on puberty suppression. The main aim of this research was to explore the psychological aspects of hormonal treatments for gender non-conforming adults, including the controversial use of puberty suppression treatments. METHODS: Using a semi-structured interview format, ten adult trans-women were interviewed (mean age: 37.4) to explore their personal histories regarding GD onset and development, their HT experiences, and their views on the use of GnRH analogs to suppress puberty in trans-children and adolescents. RESULTS: the interview transcripts were analyzed using the consensual qualitative research method from which several themes emerged: the onset of GD, childhood experiences, experiences with puberty and HT, views on the puberty suspension procedure, and the effects of this suspension on gender identity and sexuality. CONCLUSIONS: The interviews showed that overall, the participants valued the new treatment protocol due to the opportunity to prevent the severe body dysphoria and social phobia trans-people experience with puberty. It seems that the risk of social isolation and psychological suffering is increased by the general lack of acceptance and stigma toward trans-identities in the Italian society. However, during gender transitions, they highlight the need to focus more on internal and psychological aspects, rather than over-emphasize physical appearance. This study gives a voice to an under-represented group regarding the use of GnRH analogs to suppress puberty in trans-individuals, and collected firsthand insights on this controversial treatment and its recommendations in professional international guidelines.


Asunto(s)
Cultura , Disforia de Género/tratamiento farmacológico , Antagonistas de Hormonas/uso terapéutico , Percepción , Pubertad/efectos de los fármacos , Personas Transgénero/psicología , Transexualidad/psicología , Adolescente , Adulto , Femenino , Disforia de Género/epidemiología , Identidad de Género , Hormona Liberadora de Gonadotropina/análogos & derivados , Hormona Liberadora de Gonadotropina/uso terapéutico , Terapia de Reemplazo de Hormonas/psicología , Humanos , Entrevistas como Asunto , Masculino , Memoria/fisiología , Persona de Mediana Edad , Procedimientos de Reasignación de Sexo , Maduración Sexual/efectos de los fármacos , Encuestas y Cuestionarios , Transexualidad/terapia , Adulto Joven
7.
Allergol Immunopathol (Madr) ; 47(1): 60-63, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30193885

RESUMEN

BACKGROUND: Food allergy is a very frequent and increasingly common disease in children and adolescents. It affects quality of life and can even be life-threatening. Given that 10-18% of allergic/anaphylactic food reactions take place in schools, it is essential to provide school personnel with training on the management of reactions. METHODS: The Allergy Unit of Hospital Universitario de Fuenlabrada, Spain, organized a conference entitled "Management of Food Allergy in Children and Adolescents in School Centers" during which teachers, cooks, cafeteria monitors, and summer-camp leaders underwent a training course. Attendees filled out a questionnaire with eight questions before and after the course to assess their self-efficacy in management of food allergy and anaphylaxis. The results were compared. RESULTS: A total of 191 people participated (51% dining-room monitors, 24% teachers, 13% cooks, and 12% other professions). The areas in which the attendees presented the lowest confidence before receiving the course were recognition of symptoms and treatment of the reactions/anaphylaxis. The mean score for each of the eight concepts evaluated improved after the training course. This improvement was significant in the management of anaphylaxis. CONCLUSIONS: Our study demonstrates the usefulness of a self-efficacy scale in school personnel as a tool to assess the ability to manage food allergy and anaphylaxis. It can help to identify problem areas in which more specific training programs can be implemented.


Asunto(s)
Anafilaxia/epidemiología , Hipersensibilidad a los Alimentos/epidemiología , Maestros , Instituciones Académicas , Formación del Profesorado , Adulto , Educación Profesional , Eficiencia Organizacional , Epinefrina/administración & dosificación , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Persona de Mediana Edad , España/epidemiología , Encuestas y Cuestionarios , Adulto Joven
8.
J Med Syst ; 43(10): 311, 2019 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-31451951

RESUMEN

Heart rate variability (HRV) analysis is a powerful instrument that provides information about the heart conditions. However, there exist some limitations in the use of HRV in the clinical practice. Examples are the lack of reference values for healthy populations, different HR (Heart Rate) acquisition systems, and varying software packages. Other factors that affect HRV values are the influence of lifestyle, drugs and alcohol consumption, and pollution. In this work, recommendations to perform HRV-based experiments were established. These suggestions refer to best moment of the day to record data, the optimal body position, and the quality and duration of the recorded signals. In this way, HR data from 6 healthy subjects (2 women, 4 men), with median age of 50 years old, were recorded during 15 days, 3 times a day. Recordings were performed in the following situations: both supine and sitting body positions, in the morning, in the afternoon and at night. Data were processed and HRV analysis was performed. Distorting factors affecting HRV have been determined. The most stable HRV indexes (less variation over the days) have also been established. For this task, a variation coefficient was calculated for each parameter, as the ratio between the standard deviation and the mean value. Results indicated that HR data should be recorded in the morning, the sitting position. Related to signals duration, when comparing HR signals, they should be of equal length (same recording time). In addition, HRVi (HRV triangular index) and MADRR (median of the absolute differences between adjacent RR intervals) resulted in the most robust indexes in both low and high frequency domains. For global indexes, the ApEn (approximate entropy) measure emerged as the most stable one. As a conclusion, researchers must be extremely cautious in studies involving HRV analysis; the moment of the day to record data, the body position, or the quality of recorded data will produce different HR signals, and thus, the values of the HRV parameters will be different in each case. This may clearly bias the conclusions of the study.


Asunto(s)
Frecuencia Cardíaca/fisiología , Monitoreo Fisiológico/métodos , Práctica Clínica Basada en la Evidencia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Postura , Valores de Referencia , Procesamiento de Señales Asistido por Computador , Factores de Tiempo
9.
Med Vet Entomol ; 32(2): 162-174, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29165810

RESUMEN

In Mexico, mosquito vector-borne diseases are of public health concern as a result of their impact on human morbidity and mortality. The use of insecticides against adult mosquitoes is one of the most common ways of controlling mosquito population densities. However, the use of these compounds has resulted in the development of insecticide resistance. The aim of this study was to estimate susceptibility to six pyrethroids, two carbamates and two organophosphates in Mexican populations of Stegomyia aegypti (Linnaeus, 1762) (= Aedes aegypti) (Diptera: Culicidae) mosquitoes. Bottle insecticide susceptibility tests, with 1 h exposure, were performed on adult mosquitoes from 75 localities across 28 states. At 30 min of exposure, the proportion of fallen mosquitoes was recorded. After 60 min of exposure, mosquitoes were recovered in non-treated containers and mortality was determined at 24 h after the set-up of the experiment. In general, the carbamate insecticides represented the most effective group in terms of the proportion of mosquitoes fallen at 30 min (72-100%) and 24-h mortality (97-100%). High and widespread resistance to pyrethroids Types I and II and, to a lesser extent, to organophosphates was observed. Insecticide susceptibility among and within states was highly variable.


Asunto(s)
Aedes/efectos de los fármacos , Carbamatos/farmacología , Resistencia a los Insecticidas , Insecticidas/farmacología , Organofosfatos/farmacología , Piretrinas/farmacología , Animales , Femenino , México
10.
Scand J Med Sci Sports ; 28(7): 1801-1807, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29469938

RESUMEN

The aim of this study was to analyze the mediation role of cardiorespiratory fitness and waist circumference in the association between muscular strength and cardiometabolic risk. A cross-sectional study involved first-year college students (n = 370) from a Spanish public university was performed. We measured weight, height, waist circumference, blood pressure, biochemical variables, maximum handgrip strength assessment, and cardiorespiratory fitness. We calculated handgrip dynamometry/weight and a previously validated cardiometabolic risk index. Analysis of covariance models was conducted to test differences in cardiometabolic risk values across muscular strength, cardiorespiratory fitness, and waist circumference categories, controlling for confounders. Hayes' PROCESS macro was used for the multiple mediation analysis. The relationship between muscular strength and cardiometabolic risk did not remain significant (c' = 1.76 [1.4]; P > .05) in a multiple serial bootstrapped mediation model including cardiorespiratory fitness and waist circumference as mediators when controlling for age and sex. According to the indirect effect, the significant paths in the model mediating this relationship between muscular strength and cardiometabolic risk index were as follows: muscular strength → waist circumference → cardiometabolic risk index (-4.899; 95% CI: -6.690; -3.450) and muscular strength → cardiorespiratory fitness → waist circumference → cardiometabolic risk index (-0.720; 95% CI: -1.316; -0.360). Both cardiorespiratory fitness and waist circumference mediate the association between muscular strength and cardiometabolic risk in young adults. Thus, our results place cardiorespiratory fitness and waist circumference as the main targets of physical activity programmes aimed at preventing cardiometabolic diseases.


Asunto(s)
Capacidad Cardiovascular , Fuerza de la Mano , Circunferencia de la Cintura , Adolescente , Presión Sanguínea , Peso Corporal , Estudios Transversales , Femenino , Humanos , Masculino , Adulto Joven
11.
Med Vet Entomol ; 31(2): 240-242, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28106260

RESUMEN

Stegomyia aegypti (= Aedes aegypti) (Diptera: Culicidae) is a species of mosquito that is currently widespread in Mexico. Historically, the mosquito has been distributed across most tropical and subtropical areas lower than 1700 m a.s.l. Currently, populations that are found at higher altitudes in regions with cold and dry climates suggest that these conditions do not limit the colonization and population growth of S. aegypti. During a survey of mosquitoes in September 2015, larvae of S. aegypti mosquitoes were found in two different localities in Mexico City, which is located at about 2250 m a.s.l. Mexico City is the most populous city in Mexico and has inefficient drainage and water supply systems. These factors may result in the provision of numerous larval breeding sites. Mosquito monitoring and surveillance are now priorities for the city.


Asunto(s)
Aedes/fisiología , Distribución Animal , Insectos Vectores/fisiología , Aedes/crecimiento & desarrollo , Animales , Insectos Vectores/crecimiento & desarrollo , Larva/crecimiento & desarrollo , Larva/fisiología , México
12.
Pharmacol Res ; 110: 205-215, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27013280

RESUMEN

Cannabinoids have emerged as promising neuroprotective agents due to their capability to activate specific targets, which are involved in the control of neuronal homeostasis and survival. Specifically, those ligands that selectively target and activate the CB2 receptor may be useful for their anti-inflammatory and neuroprotective properties in various neurological disorders, with the advantage of being devoid of psychotropic effects associated with the activation of CB1 receptors. The aim of this work has been to investigate the neuroprotective properties of 7-(1,1-dimethylheptyl)-4,4-dimethyl-9-methoxychromeno[3,4-d]isoxazole (PM226), a compound derived from a series of chromeno-isoxazoles and -pyrazoles, which seems to have a promising profile related to the CB2 receptor. The compound binds selectively to this receptor with an affinity in the nanomolar range (Ki=12.8±2.4nM). It has negligible affinity for the CB1 receptor (Ki>40000nM) and no activity at the GPR55. PM226 was also evaluated in GTPγS binding assays specific to the CB2 receptor showing agonist activity (EC50=38.67±6.70nM). In silico analysis of PM226 indicated that it has a good pharmacokinetic profile and a predicted ability to cross the blood-brain barrier. Next, PM226 was investigated in an in vitro model to explore its anti-inflammatory/neuroprotective properties. Conditioned media were collected from LPS-stimulated cultures of BV2 microglial cell line in the absence or presence of different doses of PM226, and then media were added to cultured M213-2O neuronal cells to record their influence on cell viability evaluated using MTT assays. As expected, cell viability was significantly reduced by the exposure to these conditioned media, while the addition of PM226 attenuated this reduction in a dose-dependent manner. This effect was reversed by co-incubating with the CB2 antagonist SR144528, thus confirming the involvement of CB2 receptors, whereas the addition of PM226 to neuronal cultures instead cultured BV2 cells was not effective. PM226 has also been studied in an in vivo model of mitochondrial damage generated by intrastriatal application of malonate in rats. MRI analysis showed that PM226 administration decreased the volume of the striatal lesion caused by malonate, effect that was confirmed after the histopathological evaluation (Nissl staining, Iba-1 immunostaining and TUNEL assay) of striatal sections derived from malonate-lesioned rats in the absence or presence of PM226. Again, the beneficial effects of PM226 were dependent on the activation of CB2 receptors as they were reversed by blocking these receptors with AM630. Overall, PM226 has shown to have a promising neuroprotective profile derived from its ability to selectively activate CB2 receptor, so that it could be a useful disease-modifying agent in those neurodegenerative pathologies in which the activation of these receptors may have therapeutic value.


Asunto(s)
Lesiones Encefálicas/tratamiento farmacológico , Encéfalo/efectos de los fármacos , Agonistas de Receptores de Cannabinoides/farmacología , Isoxazoles/farmacología , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Receptor Cannabinoide CB2/agonistas , Animales , Sitios de Unión , Barrera Hematoencefálica/metabolismo , Encéfalo/metabolismo , Encéfalo/patología , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/patología , Agonistas de Receptores de Cannabinoides/síntesis química , Agonistas de Receptores de Cannabinoides/metabolismo , Agonistas de Receptores de Cannabinoides/farmacocinética , Línea Celular , Modelos Animales de Enfermedad , Humanos , Isoxazoles/síntesis química , Isoxazoles/metabolismo , Isoxazoles/farmacocinética , Masculino , Malonatos , Ratones , Modelos Biológicos , Degeneración Nerviosa , Neuronas/metabolismo , Neuronas/patología , Fármacos Neuroprotectores/síntesis química , Fármacos Neuroprotectores/metabolismo , Fármacos Neuroprotectores/farmacocinética , Permeabilidad , Unión Proteica , Ratas Wistar , Receptor Cannabinoide CB2/química , Receptor Cannabinoide CB2/genética , Receptor Cannabinoide CB2/metabolismo , Transfección
13.
Phys Chem Chem Phys ; 18(18): 12755-67, 2016 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-27097793

RESUMEN

Cis and trans proline conformers are often associated with dramatic changes in the biological function of peptides. A slow equilibrium between cis and trans Ile-Pro amide bond conformers occurs in constrained derivatives of the native marine cyclic heptapeptide stylostatin 1 (cyclo-(NSLAIPF)), a potential anticancer agent. In this work, four cyclopeptides, cyclo-(NSTAIPF), cyclo-(KSTAIPF), cyclo-(RSTAIPF) and cyclo-(DSTAIPF), which are structurally related to stylostatin 1, are experimentally and computationally examined in order to assess the effect of residue mutations on the cis-trans conformational ratio and the apparent capacity to form dimeric aggregates. Primarily, cyclo-(KSTAIPF) and cyclo-(RSTAIPF) showed specific trends in circular dichroism, MALDI-TOF and HPLC purification experiments, which suggests the occurrence of peptide dimerization. Meanwhile, the NMR spectrum of cyclo-(KSTAIPF) indicates that this cyclopeptide exists in the two slow-exchange families of conformations mentioned above. Molecular dynamics simulations combined with quantum mechanical calculations have shed light on the factors governing the cis/trans conformational ratio. In particular, we have found that residue mutations affect the internal hydrogen bond pattern which ultimately tunes the cis/trans conformational ratio and that only trans conformers are capable of aggregating due to the shape complementarity of the two subunits.


Asunto(s)
Péptidos Cíclicos/química , Prolina/química , Dimerización , Isomerismo , Espectroscopía de Resonancia Magnética , Simulación de Dinámica Molecular , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
14.
Genet Mol Res ; 15(1)2016 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-26909995

RESUMEN

The aim of this study was to analyze the allelic frequency distribution and segregation among breeds and/or between different cattle genetic groups of four novel single nucleotide polymorphisms of the bovine DRD1 and DRD5 genes and one reported SNP from the DRD4 gene. One hundred and nine-animals from ten different cattle breeds were genotyped and allelic frequencies for each locus were estimated. There were significant differences in the allelic frequencies (P < 0.05) among breeds for the DRD1 and DRD5 markers. The allelic frequencies for markers DRD1-825A>G and DRD5-378C>T were also significantly different between groups differing in genetic background. Because differences in temperament have been reported between Bos taurus taurus and B. taurus indicus breeds and their crosses, further studies are needed to investigate if any association exists between described markers and cattle behavior traits.


Asunto(s)
Polimorfismo de Nucleótido Simple , Carácter Cuantitativo Heredable , Receptores Dopaminérgicos/genética , Temperamento , Alelos , Animales , Conducta Animal , Cruzamiento , Bovinos , Femenino , Frecuencia de los Genes , Genotipo , Masculino , Fenotipo , Análisis de Componente Principal , Isoformas de Proteínas/genética
15.
Hum Reprod ; 30(9): 2138-51, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26109618

RESUMEN

STUDY QUESTION: Does fibronectin (Fn) stimulate the sperm capacitation process in humans? SUMMARY ANSWER: Fibronectin stimulates human sperm capacitation. WHAT IS KNOWN ALREADY: Capacitation is a process that occurs in the oviduct. It has been suggested that some molecules present in the oviductal fluid and cells as well as proteins present in the cumulus oophorus could be involved in the modulation of sperm function and their acquisition of fertilizing capacity. Fibronectin is a glycoprotein that is present in the fluid and the oviduct epithelium, and its receptor (alpha 5 beta 1 integrin) is present in human sperm. When alpha 5 beta 1 (α5ß1) integrin binds to fibronectin, intracellular signals similar to the process of sperm capacitation are activated. STUDY DESIGN, SIZE, DURATION: Human sperm were selected via a percoll gradient and were then incubated in non-capacitated medium (NCM) or reconstituted capacitated medium (RCM), in the presence or absence of fibronectin for different time periods. A total of 39 donors were used during the study, which lasted 3 years. PARTICIPANTS/MATERIALS, SETTING, METHODS: Freshly ejaculated sperm from healthy volunteers were obtained by masturbation. All semen samples were normal according to the World Health Organization parameters. Six approaches were used to determine the effects of fibronectin on sperm capacitation: chlortetracycline (CTC) assay, heterologous co-culture of human sperm with bovine oviductal epithelial cells (BOEC), measurement of cyclic (c) AMP levels, activity of protein kinase A (PKA), phosphorylation of proteins in tyrosine (Tyr) residues, and induction of acrosome reaction with progesterone. MAIN RESULTS AND THE ROLE OF CHANCE: When sperm were incubated in RCM in the presence of Fn, we observed differences with respect to sperm incubated in RCM without Fn (control): (i) a 10% increase in the percentage of sperm with the B pattern (capacitated sperm) of CTC fluorescence from the beginning of capacitation (P < 0.001); (ii) an effect on both the concentration of cAMP (P < 0.05) and PKA activity (P < 0.05) during early capacitation; (iii) an increase in the degree of phosphorylation of proteins on tyrosine residues after 60 min of capacitation (P < 0.01); (iv) an increase in the percentage of acrosome-reacted sperm in response to progesterone (P < 0.05); and (v) a decrease in the percentage of sperm attached to BOEC (P < 0.05). Moreover, we noted that the effect of Fn was specific and mediated by alpha 5 beta 1 integrin (P < 0.001). Fn by itself had no effect on sperm capacitation. LIMITATIONS, REASONS FOR CAUTION: This study was carried out with sperm from young adult men. Men with abnormal semen samples were excluded. The results cannot be directly extrapolated to other mammalian species. WIDER IMPLICATIONS OF THE FINDINGS: Currently, male subfertility has become a huge public health problem, which makes it imperative to develop new treatments. This is a novel discovery that extends our current knowledge concerning normal and pathological sperm physiology as well as events that regulate the process of fertilization. STUDY FUNDING/COMPETING INTERESTS: This study was supported by grants from FONDECYT (1130341, E.S.D. and 1120056, P.M.) and FONCYT (PIP 2011-0496, S.P.-M). The authors have no conflicts of interest.


Asunto(s)
Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Fibronectinas/fisiología , Transducción de Señal/fisiología , Capacitación Espermática/fisiología , Adulto , Humanos , Masculino , Adulto Joven
16.
Folia Biol (Praha) ; 61(1): 33-42, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25958309

RESUMEN

Many classes of silver nanoparticles (AgNPs) have been synthesized and widely applied, but no conclusive information on their potential cytotoxicity and genotoxicity mechanisms is available. Therefore, the purpose of this study was to compare the potential genotoxic effects (DNA strand breaks and oxidative DNA damage) of 4.7 nm coated and 42 nm uncoated AgNPs, using the comet assay, in four relevant human cell lines (hepatoma, leukaemia, and dermal and pulmonary fibroblasts) in order to understand the impact of such nanomaterials on cellular DNA. The results indicated that in all cell lines tested, 4.7 nm coated (0.1-1.6 µg ml⁻¹) and 42 nm uncoated (0.1-6.7 µg ml⁻¹) AgNPs increased DNA strand breaks in a dose- and size-dependent manner following 24 h treatment, the smaller AgNPs being more genotoxic. Human pulmonary fibroblasts showed the highest sensitivity to the AgNPs. A modified comet assay using endonuclease III and formamidopyrimidine- DNA glycosylase restriction enzymes showed that in tumoral and normal human dermal fibroblasts, pyrimidines and purines were oxidatively damaged by both AgNPs, but the damage was not size-dependent. However, in human pulmonary fibroblasts, no oxidative damage was observed after treatment with 42 nm AgNPs. In conclusion, both AgNP sizes induced DNA damage in human cells, and this damage could be related to oxidative stress.


Asunto(s)
Carcinoma Hepatocelular/patología , Roturas del ADN de Doble Cadena/efectos de los fármacos , Fibroblastos/patología , Leucemia/patología , Neoplasias Hepáticas/patología , Nanopartículas del Metal/toxicidad , Plata/toxicidad , Línea Celular , Dermis/patología , Fibroblastos/efectos de los fármacos , Humanos , Pulmón/patología , Nanopartículas del Metal/química , Oxidación-Reducción , Tamaño de la Partícula , Plata/química
17.
Lett Appl Microbiol ; 59(2): 127-32, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24785827

RESUMEN

UNLABELLED: Bacterial comfort is central to biotechnological applications. Here, we report the characterization of different sensoring systems, the first step within a broader synthetic biology-inspired light-mediated strategy to determine Escherichia coli perception of environmental factors critical to bacterial performance. We did so by directly 'asking' bacterial cultures with light-encoded questions corresponding to the excitation wavelength of fluorescent proteins placed under the control of environment-sensitive promoters. We built four genetic constructions with fluorescent proteins responding to glucose, temperature, oxygen and nitrogen; and a fifth construction allowing UV-induced expression of heterologous genes. Our engineered strains proved able to give feedback in response to key environmental factors and to express heterologous proteins upon light induction. This light-based dialoguing strategy reported here is the first effort towards developing a human-bacteria interphase with both fundamental and applied implications. SIGNIFICANCE AND IMPACT OF THE STUDY: The results we present here are at the core of a larger synthetic biology research effort aiming at establishing a dialogue with bacteria. The framework is to convert the human voice into electric pulses, these into light pulses exciting bacterial fluorescent proteins, and convert light-emission back into electric pulses, which will be finally transformed into synthetic voice messages. We report here the first results of the project, in the form of light-based determination of key parameters for bacterial comfort. The ultimate goal of this strategy is to combine different engineered populations to have a combined feedback from the pool.


Asunto(s)
Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica/efectos de la radiación , Escherichia coli/metabolismo , Escherichia coli/efectos de la radiación , Interacción Gen-Ambiente , Genes Bacterianos , Genes Reporteros , Glucosa/fisiología , Proteínas Fluorescentes Verdes/biosíntesis , Proteínas Fluorescentes Verdes/genética , Nitrógeno/fisiología , Oxígeno/fisiología , Regiones Promotoras Genéticas , Biología Sintética , Activación Transcripcional/efectos de la radiación
18.
Obes Surg ; 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38760651

RESUMEN

PURPOSE: Laparoscopic Roux-en-Y Gastric Bypass (LRYGB) remains the most effective procedure to treat severe obesity with proven short- and intermediate-term benefits. The main goal is to describe the effects on weight and biochemical laboratory tests after long-term follow-up (11 years). MATERIALS AND METHODS: A prospective cohort of adults with obesity treated with LRYGB between 2004 and 2010 in one center were studied. Patients with prior bariatric or upper digestive tract surgery, hiatal hernia >4 cm, alcoholism, or decompensated conditions were excluded. The study enrolled 123 patients, with a mean follow-up of 133±29 months and a 14% loss of participants. RESULTS: The percentage of Total Weight Loss (%TWL) at one, five, and eleven years was 30.3±8.4%, 29.1±6.9%, and 23.4±7%, respectively. Of the patients, 61.3% (65/106) maintained a %TWL≥20 after eleven years. Recurrent Weight Gain (RWG) at five and eleven years was 2.6±11.4% and 11 ±11.5%, respectively. At the end of the follow-up, 31.1% (33/106) of patients had RWG≥15%. Hypercholesterolemia and hypertriglyceridemia improved in 85.7% (54/63) and 90.2% (7/61) of the cohort, respectively. Remission of diabetes occurred in 80% of this subgroup. Gallstones developed in 28% of patients, and bowel obstruction due to internal hernia occurred in 9.4%. Anemia due to iron deficiency appeared in 25 patients. CONCLUSION: After surgery, there is a significant and durable loss of weight, with a tendency for late Recurrent Weight Gain. Furthermore, the improvement in biochemical parameters is sustained over time, but surgery's adverse effects may appear later.

19.
Food Res Int ; 182: 114162, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38519186

RESUMEN

Whey is a by-product derived from cheese making. Despite being rich in nutrients, it is little used, it even represents a problem form the environment in Mexico. In this sense, it is important to know the meanings that are associated with this term, especially when it is intended to develop new products from this by-product. The objective of this work was to analyze the representation of the term whey in rural and urban populations through the Central core Theory. Additionally, the relationship between gender-place of residence with the evoked word is explored. Therefore, three hundred and sixty people (from rural and urban areas) were interviewed face to face in two areas in the western region of Mexico. Word association test was carried out, using "whey" as stimulus; the associated words were ordered according to their importance; the polarity index of each associated word was evaluated. The most frequently mentioned words were analyzed based on their frequency of mention and average importance to identify the conceptual structure of the concept representation. The results show and influence of the place of residence on the conceptual structure. Rural participants tend to generate more words with negative connotations, while the central elements of urban consumers are mainly related to dairy products. When comparing consumers by gender, rural and urban women associate "whey" with aspects of both the production process and dairy products. In the case of men, those from the urban zone, relate to aspects related to nutrition, dairy products and nutrients. In contrast, men from the rural area relate whey mainly to negative aspects such as pollution. The study confirms that there is a link between the place of residence and the conformation of the conceptual structure, where the gender-region relationship influences the definition of the term "whey".


Asunto(s)
Productos Lácteos , Suero Lácteo , Masculino , Humanos , Femenino , México , Población Urbana , Proteína de Suero de Leche/química
20.
Hum Reprod ; 28(1): 189-98, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23108346

RESUMEN

STUDY QUESTION: Is it possible to perform allogeneic uterus transplantation (UTx) with a donation from a live donor in a non-human primate species and what immunosuppression is needed to prevent rejection? SUMMARY ANSWER: Allogeneic UTx in the baboon is a donor- and recipient-safe surgical procedure; immunosuppression with induction therapy and a triple protocol should be used. WHAT IS KNOWN ALREADY: UTx may become a treatment for absolute uterine factor infertility. Autologous UTx models have been developed in non-human primates with reports on long-term survival of the uterine grafts. STUDY DESIGN, SIZEAND DURATION: This experimental study included 18 female baboons as uterus donors and 18 female baboons as uterus recipients. The follow-up time was 5-8 weeks. PARTICIPANTS/MATERIALS, SETTING AND METHODS: Uterus retrieval was performed with extended hysterectomy including bilateral uterine and internal iliac arteries and ovarian veins. After UTx, with vascular anastomoses unilateral to the internal iliac artery and the external iliac vein, the uterus recipients received one of the following: no immunosuppression (n = 4); monotherapy (oral slow release tacrolimus) (n = 4) or induction therapy (antithymocyte globulin) followed by triple therapy (tacrolimus, mycophenolate, corticosteroids; n = 10). Surgical parameters, survival, immunosuppression and rejection patterns were evaluated. MAIN RESULTS AND THE ROLE OF CHANCE: The durations of uterus retrieval and recipient surgery were around 3 and 3.5 h, respectively. The total ischemic time was around 3 h. All the recipients and the donors survived the surgery. All the recipients presented rejection to some extent within the first weeks following UTx. In one recipient, the uterus was of normal appearance at the end of the study period. In spite of occasional high (>60 ng/ml) blood levels of tacrolimus, there was no evidence of nephrotoxicity. LIMITATIONS AND REASONS FOR CAUTION: This initial non-human primate allogeneic UTx study indicates that further research is needed to optimize immunosuppression protocols in order to avoid uterine rejection. WIDER IMPLICATIONS OF THE FINDINGS: The findings suggest that allogeneic UTx in primate species is feasible but continued work on this issue is needed. STUDY FUNDING/COMPETING INTEREST(S): The study was funded by the Swedish Research Council, ALF University of Gothenburg, Hjalmar Svensson Foundation and by Jane and Dan Olsson Research Foundation. The authors do not have any competing interest.


Asunto(s)
Modelos Animales de Enfermedad , Terapia de Inmunosupresión/métodos , Quimioterapia de Inducción , Infertilidad Femenina/cirugía , Enfermedades Uterinas/fisiopatología , Útero/trasplante , Corticoesteroides/uso terapéutico , Animales , Suero Antilinfocítico/uso terapéutico , Quimioterapia Combinada , Estudios de Factibilidad , Femenino , Rechazo de Injerto/prevención & control , Supervivencia de Injerto/efectos de los fármacos , Infertilidad Femenina/etiología , Donadores Vivos , Quimioterapia de Mantención , Ácido Micofenólico/uso terapéutico , Papio , Tacrolimus/uso terapéutico , Trasplante Homólogo , Útero/inmunología
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