Repositorio académico de acceso abierto (Univ. Autonóma de Chile)
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Role of Triplet States in the Photolysis of Proteogenic Amino Acids
No full textThis investigation delves into the UV photodissociation of pivotal amino acids (Alanine, Glycine, Leucine, Proline, and Serine) at 213 nm, providing insights into triplet-state deactivation pathways. Utilizing a comprehensive approach involving time-dependent density functional calculations (TD-DFT), multi-configurational methods, and ab-initio molecular dynamics (AIMD) simulations, we scrutinize the excited electronic states (T1, T2, and S1) subsequent to 213 nm excitation. Our findings demonstrate that α-carbonyl C−C bond-breaking in triplet states exhibits markedly lower barriers than in singlet states (below 5.0 kcal mol−1). AIMD simulations corroborate the potential involvement of triplet states in amino acid fragmentation, underscoring the significance of accounting for these states in photochemistry. Chemical bonding analyses unveil distinctive patterns for S1 and T1 states, with the asymmetric redistribution of electron density characterizing the C−C breaking in triplet states, in contrast to the symmetric breaking observed in singlet states. This research complements recent experimental discoveries, enhancing our comprehension of amino acid reactions in the interstellar medium. © 2023 Wiley-VCH GmbH.Andrés Bello University, (DI-05-23/REG
Valoración de tecnologías inmersivas y enfoque STEM en la formación inicial del profesorado
No full textIn recent years, there has been a growing interest in the integration of various Emerging Technologies in the field of Education, especially immersive technologies such as Virtual Reality (VR) and Augmented Reality (AR). This research aims at assessing the perceived usefulness of these technologies by pre-service teachers at the Faculty of Educational Sciences of the University of Granada, specifically in the STEM field, and how they evaluate their potential for integration into their future teaching practices. A mixed-methods approach was used, including a pre-questionnaire administered to the entire population (N=544) to describe the participants’ perceptions, followed by a post-test conducted with a subset (N=58) after having participated in a Complementary Training program focusing on the creation of immersive educational resources using the CoSpaces platform. The results revealed a high perceived utility of immersive technologies, highlighting their potential for enhancing teaching and learning in the STEM domain. However, challenges related to ease of integration and the lack of adequate training in the use of these technologies were identified. The importance of promoting teacher training and digital literacy to fully leverage the benefits of these emerging technologies in education is emphasized. Further research is suggested to delve into teacher training strategies and explore other educational contexts to expand the understanding of the implications and advantages of immersive technologies. © 2024, Ibero-American Association for Distance Higher Education (AIESAD). All rights reserved.European Commission, EC; Agencia Nacional de Investigación y Desarrollo, ANID, (72210075, TED2021-129474B-I00)Universidad Autónoma de Chil
Role of Ubiquitin-proteasome system in Espematogenesis
No full textSpermatogenesis is a series of events that constitute programmed cell differentiation, with dramatic changes in morphology, biochemistry and gene expression which are regulated by temporal and especially endocrine, paracrine and autocrine mechanisms. During the various stages of spermatogenesis and particularly during the differentiation of spermatids, there is massive degradation of cytosolic proteins, nuclear and membrane due to the elimination of much of the cytoplasm which has round spermatid. This protein degradation occurs within the seminiferous epithelium and is mediated by cellular systems described for this purpose. The proteasome is a multienzyme complex responsible for degrading the majority of nuclear and cytosolic proteins, after they are marked for destruction by covalent attachment of ubiquitin molecules. This selective destruction of cellular proteins is a key mechanism in the process of spermatogenesis. This article discusses the basics of male gonadal physiological process and the current understanding of the role of the ubiquitin proteasome system in the functional maintenance of spermatogenesis are reviewed
Pharmacological and Surgical Treatment for Trigeminal Neuralgia a Review of the Literature
No full textTrigeminal neuralgia is the most common orofacial pain, with incidence levels that increase every year. Characterized by paroxysmal attacks of pain, brief, lancinating, stabbing, is considered one of the most painful conditions affecting patients. Drug therapy has been the gold standard for the management and control of this neuropathy, on the contrary, recent studies find wide drug resistance with history of neuralgia for many years, causing recurrence of the picture. That is why there is a need to establish a proper surgical planning, among which stands vascular decompression and percutaneous micro harmful methods such as retrogasserianas rhizotomies, chemical methods, such as injection of alcohol or glycerol in the oval hole, mental foramen, as an alternative to medical-pharmacological treatment, however, not all procedures reviewed in the literature indicate a continued success rate and further, the various adverse effects involving the implementation of each treatment should be considered
Impact of timing of antihypertensive treatment on mortality: An observational study from the Spanish Ambulatory Blood Pressure Monitoring Registry
No full textBackground and aims:Whether bedtime versus morning administration of antihypertensive therapy is beneficial on outcomes is controversial. We evaluated the risk of total and cardiovascular mortality in a very large observational cohort of treated hypertensive patients, according to the timing of their usual treatment administration (morning versus evening).Methods:Vital status and cause of death were obtained from death certificates of 28 406 treated hypertensive patients (mean age 62 years, 53% male individuals), enrolled in the Spanish Ambulatory Blood Pressure Monitoring (ABPM) Registry between 2004 and 2014. Among the 28 406 patients, most (86%) received their medication exclusively in the morning; whilst 13% were treated exclusively in the evening or at bedtime. Follow-up was for a median of 9.7 years and 4345 deaths occurred, of which 1478 were cardiovascular deaths.Results:Using Cox-models adjusted for clinical confounders and 24-h SBP, and compared with patients treated in the morning (reference group), all-cause mortality [hazard ratio 1.01; 95% CI 0.93-1.09) and cardiovascular mortality (hazard ratio 1.04; 95% CI 0.91-1.19) was not significantly different in those receiving evening medication dosing. The results were consistent in all the subgroups of patients analysed.Conclusion:In this very large observational study, morning versus bedtime dosing of antihypertensive medication made no difference to the subsequent risk of all-cause or cardiovascular mortality. These findings are in accordance with results from a recent randomized controlled trial and do not support the hypothesis of a specific beneficial effect of night-time antihypertensive treatment dosing on risk of all-cause or cardiovascular death. © 2024 Lippincott Williams and Wilkins. All rights reserved.Lacer Laboratories; Spanish Society of Hypertension; National Institute for Health and Care Research, NIHR; University College London Hospitals Biomedical Research Centre, UCLH BR
Sex and disease severity-based analysis of steroid hormones in ME/CFS
No full textPurpose: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating disease characterized by persistent fatigue and decreased daily activity following physical and/or cognitive exertion. While ME/CFS affects both sexes, there is a higher prevalence in women. However, studies evaluating this sex-related bias are limited. Methods: Circulating steroid hormones, including mineralocorticoids (aldosterone), glucocorticoids (cortisol, corticosterone, 11-deoxycortisol, cortisone), androgens (androstenedione, testosterone), and progestins (progesterone, 17α-hydroxyprogesterone), were measured in plasma samples using ultra-high performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS). Samples were obtained from mild/moderate (ME/CFSmm; females, n=20; males, n=8), severely affected patients (ME/CFSsa; females, n=24; males, n=6), and healthy controls (HC, females, n=12; males, n=17). Results: After correction for multiple testing, we observed that circulating levels of 11-deoxycortisol, 17α-hydroxyprogesterone in females, and progesterone in males were significantly different between HC, ME/CFSmm, and ME/CFSsa. Comparing two independent groups, we found that female ME/CFSsa had higher levels of 11-deoxycortisol (vs. HC and ME/CFSmm) and 17α-hydroxyprogesterone (vs. HC). In addition, female ME/CFSmm showed a significant increase in progesterone levels compared to HC. In contrast, our study found that male ME/CFSmm had lower circulating levels of cortisol and corticosterone, while progesterone levels were elevated compared to HC. In addition to these univariate analyses, our correlational and multivariate approaches identified differential associations between our study groups. Also, using two-component partial least squares discriminant analysis (PLS-DA), we were able to discriminate ME/CFS from HC with an accuracy of 0.712 and 0.846 for females and males, respectively. Conclusion: Our findings suggest the potential value of including steroid hormones in future studies aimed at improving stratification in ME/CFS. Additionally, our results provide new perspectives to explore the clinical relevance of these differences within specific patient subgroups. Graphical abstract: (Figure presented.) © The Author(s) 2024.FH JOANNEUM University of Applied Sciences; Universidad de Concepción, UdeC; UCL-RFH BioBank; Österreichische Gesellschaft für ME; Chicken Farmers of Saskatchewan, CFS; ME Research UK, (SC036942); Fundação para a Ciência e a Tecnologia, FCT, (UIDB/00006/2020); Agencia Nacional de Investigación y Desarrollo, ANID, (PFCHA-21190736); Ministerio de Educación, Gobierno de Chile, MINEDUC, (UCO 1866)Universidad Autónoma de Chil
Patologías del área oral en los recién nacidos e infantes: frenillos y las aportaciones de los sistemas láser
No full textThe purpose of this article is to improve our knowledge about the structures and function of the different elements present in the mouth of newborns since dentists sometimes do not remember the importance of the mouth in the general development of infants and the need for an early intervention with lasers to help them obtain a good state of their Oral System. We performed a comprehensive clinical exploration of the patient in order to make a more accurate diagnosis. When surgery is necessary, we recommend to use erbium lasers when possible (2780nm Er, Cr: YSGG laser or a 2940nm Er: YAG), as they are a quick and effective option to treat these oral lesions, specially lip or tongue ties which can risk the act of breastfeeding; moreover, we can also use diode lasers (810nm, 940nm, 980nm or a 1064nm Nd:YAG laser or CO2 10.600-9600 nm.) al lof them with their specifical safety goggles. These laser systems used by a certified professional, in collaboration with a properly trained staff, are a very important factor during the surgery.By having proper knowledge of the oral structures and their pathologies, we are able to diagnose whether those disorders should be surgically treated and if so, how to proceed with laser systems as they are minimally invasive procedures; or if we should recommend parents to visit a myofunctional therapist in order to help recover the normal function.The understanding of oral structures of newborns is very important in order to improve the development of craniofacial growth and provide an important service to mothers by giving their babies a right start in life from a very early stage. We need to improve collaboration between professionals from different disciplines in order to enhance our knowledge. El propósito de este artículo es mejorar nuestro conocimiento sobre las estructuras y función de los diferentes elementos presentes en la boca del recién nacido, ya que en ocasiones los odontólogos no recuerdan la importancia de la boca en el desarrollo general del lactante y la necesidad de una intervención temprana con láseres para ayudarles a obtener un buen estado de su sistema oral. Realizamos una exploración clínica integral del paciente con el fin de realizar un diagnóstico más preciso. Cuando la cirugía sea necesaria, recomendamos utilizar láseres de Erbio siempre que sea posible (láser de 2780nm Er, Cr: YSGG o un Er: YAG de 2940nm), ya que es una opción rápida y eficaz para tratar estas lesiones orales, especialmente los frenillos labiales o linguales que pueden poner en riesgo el acto de amamantar; Asimismo podemos utilizar láseres de diodo (810nm, 940nm, 980 nm o un láser Nd: YAG de 1064nm o de CO2 10.600- 9600 nm) con sus gafas de seguridad específicas. Estos sistemas láser utilizados por un profesional certificado, en colaboración con un personal debidamente entrenado, son un factor muy importante durante la cirugía. Al tener un conocimiento adecuado de las estructuras orales y sus patologías, podemos diagnosticar si esos trastornos deben tratarse quirúrgicamente y, de ser así, cómo proceder con los sistemas láser, ya que son procedimientos mínimamente invasivos; o si debiésemos recomendar a los padres que visiten a un terapeuta miofuncional para ayudar a recuperar la función normal. La comprensión de las estructuras orales de los recién nacidos es muy importante para promover el desarrollo del crecimiento craneofacia y para brindar un servicio importante a las madres, dándoles a sus bebés un buen comienzo en la vida desde una etapa muy temprana. Necesitamos mejorar la colaboración entre profesionales de diferentes disciplinas con el fin de mejorar nuestro conocimiento
Rheumatoid Arthritis and Periodontal Disease. Effects of Periodontal Therapy
No full textDuring the last years there has been an important increase in the research of associations between periodontal disease and some systemic diseases, looking for a relationship beyond the single epidemiological coincidence. Rheumatoid arthritis (RA) is a chronic systemic disease that damages the bone and connective tissue; despite a low prevalence in the population, the disease has a high morbidity in patients. Rheumatoid Arthritis and Periodontal Disease have common pathophysiological characteristics. A negative influence of periodontal disease over rheumatoid arthritis has been suggested, this has led to increase the interest of studying and elucidating the relationship and possible effects of periodontal therapy on the metabolic control and severity of RA
Considerations for the Prophylactic Extraction of Asymptomatic Unerupted Third Molars
No full textThe extraction of asymptomatic unerupted third molars (TMNE) is called as "prophylactic" since it try to anticipate the appearance of recognized pathological conditions that ranged from simple dental crowdings to the development of cysts and tumors. This supposed predictability and the implicit risks of this surgery have resulted in arguments that defend, question or accept under certain limits this procedure with still unresolved dilemmas. Nevertheless the clinical activity seems to be much less judicious, with reports that continue promoting the indiscriminate extraction of TMNE with total lack of symptoms or pathological processes. Since the prophylactic extraction of asymptomatic TMNE is a recurrent topic of discussion for its relevance according to the different clinical odontologic disciplines, which many of them enclose its own perspectives only to clinics or to biology, a review on different considerations of this practice is presented, the risks and benefits are discussed, and some ethical dilemmas are exposed to the promotion of a dentallex artis
Datos de investigación
No full textEl estudio se propuso analizar el concepto de sistematización, por medio de un análisis bibliométrico a la producción científica vinculada a disciplinas de las ciencias sociales y humanas.
Para responder al objetivo central del estudio se estructuró un diseño metodológico de cohorte bibliométrico.
El análisis bibliométrico se realizó utilizando la información contenida en el catálogo principal del índice Web of Science [WoS], esta decisión
responde al reconocimiento de su alta calidad, alcance, reconocimiento y niveles de impacto a nivel mundial (Barbosa-Pérez et al., 2020; Bensman &
LeydesdorY, 2009). El realizar el estudio exclusivamente en WoS, es de particular relevancia para la pregunta de investigación, toda vez que se
busca establecer la presencia del concepto en el campo de las ciencias humanas y sociales, usando la base bibliográfica de características más restrictivas y de más altos estándares científicos (Gregorio-Chaviano et al., 2021)