1,731 research outputs found
The Interplay between ROS and Ras GTPases: Physiological and Pathological Implications
The members of the RasGTPase superfamily are involved in various signaling networks responsible for fundamental cellular processes. Their activity is determined by their guanine nucleotide-bound state. Recent evidence indicates that some of these proteins may be regulated by redox agents. Reactive oxygen species (ROSs) and reactive nitrogen species (RNSs) have been historically considered pathological agents which can react with and damage many biological macromolecules including DNA, proteins, and lipids. However, a growing number of reports have suggested that the intracellular production of ROS is tightly regulated and that these redox agents serve as signaling molecules being involved in a variety of cell signaling pathways. Numerous observations have suggested that some Ras GTPases appear to regulate ROS production and that oxidants function as effector molecules for the small GTPases, thus contributing to their overall biological function. Thus, redox agents may act both as upstream regulators and as downstream effectors of Ras GTPases. Here we discuss current understanding concerning mechanisms and physiopathological implications of the interplay between GTPases and redox agents
Abordajes epistémico-metodológicos en tiempos de la transdiciplinariedad
En el marco del V Encuentro Latinoamericano de Metodología de las Ciencias Sociales, revisar, discutir y reflexionar sobre los modos de enseñar metodología de la investigación social, debiera involucrar necesariamente a la figura de Michel Serres. En relación con la propuesta del mismo, se trata de discutir nuevos métodos y epistemologías que resulten novedosas en su aplicación en el ámbito de la investigación latinoamericana.
En el trabajo nos proponemos analizar puntos neurálgicos de la propuesta de Michel Serres como un abordaje teórico-metodológico transdisciplinario susceptible de ser aplicado en la enseñanza de la metodología de la investigación. Su trabajo comprende formas de articular saberes rompiendo fronteras a través del establecimiento de conexiones, dónde el docente que se desempeña en áreas metodológicas puede ser interpretado como “tercero instruido”.
En principio Serres se nos presenta como inédito, diferente o desfocado al andar teórico consolidado a lo largo del tiempo. Su estilo es hermético, erudito, poético, haciendo uso constante de las metáforas, alegorías, paradojas, reducción al absurdo. En su discurso abundan entidades de la mitología, enredándose el tiempo y el espacio. Serrés vive tres grandes revoluciones científicas de su tiempo: el paso del cálculo infinitesimal a la geometría de estructuras algebraicas y topológicas; de la mecánica cuántica a la teoría de la información y luego de la mano de Jaques Monod, el desarrollo de la bioquímica contemporánea.
El estilo narrativo de Serrés muestra una inclinación por la cultura greco-romana, la formación matemática y las lecturas del evangelio. Filósofo, escritor, ensayista, polifacético en su formación que abarca la ingeniería naval, matemáticas, historia y filosofía de la ciencia, representa el arlequín capaz de navegar en dos culturas y dejarnos anclados en las humanidades bajo la égida del caos. No podía esperarse menos de quien ha vivido tres grandes revoluciones en las ciencias de su tiempo: el avance de las estructuras algebraicas y la topología; la teoría de la información y la bioquímica (de la mano de su amigo Jaques Monod) (Calloni. 2003)Facultad de Humanidades y Ciencias de la Educació
Molecular Crosstalk between Integrins and Cadherins: Do Reactive Oxygen Species Set the Talk?
The coordinate modulation of the cellular functions of cadherins and integrins plays an essential role in fundamental physiological and pathological processes, including morphogenesis, tissue differentiation and renewal, wound healing, immune surveillance, inflammatory response, tumor progression, and metastasis. However, the molecular mechanisms underlying the fine-tuned functional communication between cadherins and integrins are still elusive. This paper focuses on recent findings towards the involvement of reactive oxygen species (ROS) in the regulation of cell adhesion and signal transduction functions of integrins and cadherins, pointing to ROS as emerging strong candidates for modulating the molecular crosstalk between cell-matrix and cell-cell adhesion receptors
Hypokalemia during the early phase of refeeding in patients with cancer
OBJECTIVE: Refeeding syndrome occurs in patients with severe malnutrition when refeeding begins after a long period of starvation. This syndrome increases the risk of clinical complications and mortality. Hypophosphatemia is considered the primary characteristic of the syndrome. The aim of our study was to investigate the presence of other electrolyte alterations in patients with cancer during the early stage of refeeding. METHODS: In this observational study, we enrolled 34 patients with cancer of the upper aerodigestive tract receiving upfront radiotherapy who were also enrolled in a nutrition program. A caloric intake assessment, anthropometric measurements and biochemical laboratory tests were performed. RESULTS: Significant weight loss (∼20%) was found in these patients. In the patients receiving artificial nutrition, we found lower levels of potassium and total protein compared with those who were fed orally (p = 0.03 for potassium and 0.02 for protein, respectively). Patients on enteral tube feeding had a higher caloric intake compared with those who were fed orally (25±5 kcal/kg/day vs. 10±2 kcal/kg/day). CONCLUSION: Hypokalemia, like hypophosphatemia, could be a complication associated with refeeding in patients with cancer. Hypokalemia was present in the early stages of high-calorie refeeding
Calcium hydroxide nanoparticles and hypogeum environment: test to understand the best way of application
For a long time the conservation of archaeological artefacts has been based on the principles of compatibility and minimal intervention. This involves a series of partially unsolved problems, concerning the products used for deteriorated structures consolidation. The choice of materials depends on several factors such as: microclimatic conditions, application methods, and reaction time of products. Recently the employment of nanolime in the consolidation treatments of decorative carbonate matrix surfaces had a great development, thanks to multifunctional use in calcium standard-sized particles treatments. However, while the use of the nanostructured materials is described in several specialized papers, the information about the best conditions of applicability of the nanolime and its related potentiality for the consolidation in hypogeum environment is rarely considered. The present work is devoted to represent a case study with the aim to give useful elements in order to evaluate the application of nanolime. The funerary inscriptions coming from St. Callixtus Catacombs have been the object of the research carried out in situ and in laboratory, checking indirectly in the short run and in the long run the porosity variation in the materials. The present study intends to indicate the best suspension concentration on consolidation in relationship with hypogeum environment
Rituximab as a front-line therapy for adult-onset minimal change disease with nephrotic syndrome
Efeito do transplante de células derivadas da EGM sobre os padrões de oscilações cerebrais pré-ictais em modelo de epilepsia induzida por pilocarpina
Salivary Proteomics Markers for Preclinical Sjögren’s Syndrome: A Pilot Study
Primary Sjögren’s syndrome (pSS) is a complex autoimmune disorder that particularly affects the salivary and lachrymal glands, generally causing a typical dryness of the eyes and of the mouth. The disease encompasses diverse clinical representations and is characterized by B-cell polyclonal activation and autoantibodies production, including anti-Ro/SSA. Recently, it has been suggested that autoantibody profiling may enable researchers to identify susceptible asymptomatic individuals in a pre-disease state. In this pilot study, we used mass spectrometry to analyze and compare the salivary proteomics of patients with established pSS and patients with pre-clinical SS, identifying a common protein signature in their salivary fluid. We found that several inflammatory, immunity-related, and typical acinar proteins (such as MUC5B, PIP, CST4, and lipocalin 1) were differently expressed in pSS and in pre-clinical SSA+ carriers, compared to healthy controls. This suggests that saliva may closely reflect exocrine gland inflammation from the early phases of the
disease. This study confirms the value of salivary proteomics for the identification of reliable biomarkers for SS that could be identified, even in a preclinical phase of the disease
Sarcopenia and Appendicular Muscle Mass as Predictors of Impaired Fasting Glucose/Type 2 Diabetes in Elderly Women
Elderly women exhibit a high risk of type 2 diabetes (T2D), but no definitive data exist
about the possible role of postmenopausal increases in visceral adiposity, the loss of lean body
mass, or decreases in the sum of the lean mass of arms and legs (appendicular skeletal muscle
mass (ASMM)). This retrospective, longitudinal study investigated whether body composition
(bioelectrical impedance analysis) predicted the development of impaired fasting glucose (IFG) or
T2D in a cohort of 159 elderly women (age: 71 5 years, follow-up: 94 months) from southern Italy
(Clinical Nutrition and Geriatric Units of the “Mater Domini” University Hospital in Catanzaro,
Calabria region, and the “P. Giaccone ”University Hospital in Palermo, Sicily region). Sarcopenia
was defined in a subgroup of 128 women according to the EWGSOP criteria as the presence of low
muscle strength (handgrip strength <16 kg) plus low muscle mass (reported as appendicular skeletal
muscle mass <15 kg). Participants with a low ASMM had a higher IFG/T2D incidence than those
with a normal ASMM (17% vs. 6%, p-adjusted = 0.044); this finding was independent of BMI, fat
mass, waist circumference, and habitual fat intake (OR = 3.81, p = 0.034). A higher incidence of
IFG/T2D was observed in the subgroup with sarcopenia than those without sarcopenia (33% vs. 7%,
p-adjusted = 0.005) independent of BMI and fat mass (OR = 6.75, p = 0.007). In conclusion, this study
demonstrates that elderly women with low ASMM had a higher probability of developing IFG/T2D.
Further studies are needed to confirm these results in men and in other age groups
The impact of endometriosis on dietary choices and activities of everyday life: a cross-sectional study
IntroductionEndometriosis is characterized by ectopic endometrial tissue and severe pain; frequently, women afflicted by this condition resort to non-medical interventions, such as dietary modifications. The aim of this study is to assess the impact of endometriosis on dietary patterns and quality of life.MethodsAn online survey was conducted among Italian women with endometriosis to gather self-reported demographic, clinical, dietary habit, and daily life data post-diagnosis.ResultsA total of 4,078 participants were included. Following an endometriosis diagnosis, 66% reported changes in eating habits, and 92% experienced a decline in daily life. Respondents chose dietary interventions: gluten-free (15%), anti-inflammatory (8%), Mediterranean (7.1%), or ketogenic (4%) diets, to improve health and reduce symptoms. The study revealed a shift in eating habits, with increased consumption of vegetables, fruits (10%), cereals, legumes (6.6%), and fish (4.5%), while reducing dairy products (18.4%), soy-containing foods (6.7%), and high saturated fats (8%). Eating habit changes correlated with endometriosis stages and worsened daily life. Educational level, endometriosis stages, years of symptoms, and eating habit changes linked to changes in daily life.ConclusionOur findings emphasize the importance of monitoring eating behaviors to prevent unhealthy habits and malnutrition in women with endometriosis. Further studies are needed to evaluate how different diets impact symptoms and enhance daily life for these individuals
- …