Universidad de Magallanes
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Sixteen weeks of concurrent training do not increase the magnitude of the post-exercise hypotensive effect in hypercholesterolemic morbid
No full textBACKGROUND: It is widely known that concurrent exercise of moderate -intensity continuous plus resistance training (CTMICT+RT) decreases blood pressure in hypertensive and multiple patients with other comorbidities such as obesity, however, there is little information about the changes in the 'magnitude' of the post -exercise hypotension effect (PEH) observed from an 'acute' to after long-term 'chronic' exercise adaptations. To determine both acute and chronic effects of 16 weeks of exercise using CTMICT+RT in the magnitude of the systolic (SBP)/diastolic (DBP) blood pressure response of hypercholesterolemic patients with morbid obesity. Secondarily, to determine the CTMICT+RT effects on fasting plasma glucose, lipid profile and body composition. METHODS: A quasi -experimental study was designed where morbid obesity patients were assigned to normal cholesterol (Ncho, N.=19) and the hypercholesterolemia (Hcho, N.=13) groups according to their total cholesterol levels. The main outcomes were SBP/DBP blood pressure, and secondary outcomes; fasting plasma glucose, lipid profile outcomes, and body composition (body fat, lean mass, skeletal muscle mass) variables. RESULTS: Training -induced effects analyses revealed that 16 weeks of CTMICT+RT promoted significant chronic reductions in SBP in the Hcho group from pre- to post -10 min (135 vs. 119 mmHg, P=0.004). There were significant reductions in the Ncho group in Tc (188.0 vs. 117.4 mg/dL, P=0.050), and similarly, in triglycerides from before to after the CTMICT+RT intervention (188.0 vs. 117.4 mg/dL, P=0.050). The magnitude of the PEH detected in SBP in the Hcho group (-6 mmHg) was not observed and decreased post -16 weeks of CTMICT+RT (-4 mmHg, P=0.535). CONCLUSIONS: Sixteen weeks of CTMICT+RT promote acute and chronic SBP decreases in hypercholesterolemic morbid obesity patients, being the acute 'magnitude' of SBP/DBP response not increased after CTMICT+RT
Mitochondrial unfolded protein response (UPRmt): what we know thus far
No full textMitochondria are key organelles for the optimal function of the cell. Among their many functions, they maintain protein homeostasis through their own proteostatic machinery, which involves proteases and chaperones that regulate protein import and folding inside mitochondria. In the early 2000s, the mitochondrial unfolded protein response (UPRmt) was first described in mammalian cells. This stress response is activated by the accumulation of unfolded/misfolded proteins within the mitochondrial matrix, which results in the transmission of a signal to the nucleus to increase the expression of proteases and chaperones to address the abnormal mitochondrial protein load. After its discovery, this retrograde signaling pathway has also been described in other organisms of different complexities, suggesting that it is a conserved stress response. Although there are some specific differences among organisms, the mechanism of this stress response is mostly similar and involves the transmission of a signal from mitochondria to the nucleus that induces chromatin remodeling to allow the binding of specific transcription factors to the promoters of chaperones and proteases. In the last decade, proteins and signaling pathways that could be involved in the regulation of the UPRmt, including the Wnt signaling pathway, have been described. This minireview aims to summarize what is known about the mechanism of the UPRmt and its regulation, specifically in mammals and C. elegans
GOLPH3 Participates in Mitochondrial Fission and Is Necessary to Sustain Bioenergetic Function in MDA-MB-231 Breast Cancer Cells
No full textIn this study, we investigated the inter-organelle communication between the Golgi apparatus (GA) and mitochondria. Previous observations suggest that GA-derived vesicles containing phosphatidylinositol 4-phosphate (PI(4)P) play a role in mitochondrial fission, colocalizing with DRP1, a key protein in this process. However, the functions of these vesicles and potentially associated proteins remain unknown. GOLPH3, a PI(4)P-interacting GA protein, is elevated in various types of solid tumors, including breast cancer, yet its precise role is unclear. Interestingly, GOLPH3 levels influence mitochondrial mass by affecting cardiolipin synthesis, an exclusive mitochondrial lipid. However, the mechanism by which GOLPH3 influences mitochondria is not fully understood. Our live-cell imaging analysis showed GFP-GOLPH3 associating with PI(4)P vesicles colocalizing with YFP-DRP1 at mitochondrial fission sites. We tested the functional significance of these observations with GOLPH3 knockout in MDA-MB-231 cells of breast cancer, resulting in a fragmented mitochondrial network and reduced bioenergetic function, including decreased mitochondrial ATP production, mitochondrial membrane potential, and oxygen consumption. Our findings suggest a potential negative regulatory role for GOLPH3 in mitochondrial fission, impacting mitochondrial function and providing insights into GA-mitochondria communication
The foundations of the Patagonian icefields
No full textThe two vast Patagonian icefields are a global hotspot for ice-loss. However, not much is known about the total ice volume they store - let alone its spatial distribution. One reason is that the abundant record of direct thickness measurements has never been systematically exploited. Here, this record is combined with remotely-sensed information on past ice thickness mapped from glacier retreat. Both datasets are incorporated in a state-of-the-art, mass-conservation approach to produce a well-informed map of the basal topography beneath the icefields. Its major asset is the reliability increase of thicknesses values along the many marine- and lake-terminating glaciers. For these, frontal ice-discharge is notably lower than previously reported. This finding implies that direct climatic control was more influential for past ice loss. We redact a total volume for both icefields in 2000 of 5351 km3. Despite the wealth of observations used in this assessment, relative volume uncertainties remain elevated. The Southern Patagonian Icefield likely stores around 10% more ice than previously believed, according to ice thickness estimates based on remote sensing and direct measurement-informed mapping of the sub-glacial topography
Marine litter pollution in a subantarctic beach of the Strait of Magellan, Punta Arenas, Chile
No full textThis study assessed the presence of marine litter along the beach of the city of Punta Arenas, Chile. The sampling period coincided with the COVID-19 pandemic. A total of 239 plastic waste items were identified out of a total of 638 litter items. The Clean Coast Index reported within this study ranged from Clean (CCI 2-5) to Extremely dirty (CCI >20), especially near the port. The majority of litter items has been classified as originating from varied origins, as it is not possible to pinpoint a precise origin in most items. The results indicate that the predominant plastic litter in Punta Arenas is PVC. The results are discussed in relation to the sources and composition of the residues, the morpho dynamics of the coast, and the CCI is compared with other locations around the globe
Validity of Myobradypterygius hauthali von Huene, 1927 (Ichthyosauria: Ophthalmosauria) from the Early Cretaceous of Chile and Argentina
No full textEarly Cretaceous ichthyosaurs were globally distributed pelagic marine reptiles, but many remains are fragmentary, creating a Northern Hemisphere diversity bias. A rich Hauterivian locality near the Tyndall Glacier inside Torres del Paine National Park in southern Chile yields important new data regarding ichthyosaurian diversity along the Pacific margin of Gondwana. These new data will contribute to clarifying questions regarding ichthyosaur taxonomy and the palaeobiogeographical relationships between the southern Gondwanan and Northern Hemisphere ichthyosaur groups during the Early Cretaceous. Here, we describe three new ichthyosaur specimens from this locality. Two of them are referred to Myobradypterygius hauthali, expanding the distribution of this species from the Barremian of Argentina to the Hauterivian of the Chilean Patagonia. This material shows that M. hauthali differs from Platypterygius platydactylus in forefin construction and scapular morphology, supporting its classification as a separate genus within Platypterygiinae. The third specimen is a large-bodied indeterminate ophthalmosaurine ichthyosaur. This record represents the southernmost record of Ophthalmosaurinae and the first occurrence of this group from the Cretaceous of the Southern Hemisphere. These discoveries show that ophthalmosaurines and platypterygiines continued to occur sympatrically in southernmost Gondwana during the Early Cretaceous, expanding the pattern documented in Europe to the Pacific region
Vigilancia ambiental del medio bentónico y la restauración de sedimentos enriquecidos: experiencia en el estrecho de Magallanes, Chile (1999-2024)
No full textLas comunidades bentónicas han sido valoradas internacionalmente para este tipo de objetivos por ser un importante sostén de la biodiversidad del bentos, carecer de imporante movilidad y estar en contacto directo con los sedimentos, ser un importante sitio de reciblaje y secuestro de la materia orgánica de origen antrópico, facilitar la oxigenación de los sedimentos, para sostener poblaciones que son importantes y valiosos recursos alimentarios y de interés económico y por estar expuestos a una serie de residuos tratados y no tratados por diferentes fuentes industriales. Adicionalmente, el tipo de fauna bentónica presente nos puede permitir conocer el estado de calidad de ambiental de los sedimentos
First detection in Argentina and new records in Chile of Boisea trivittata (Say, 1825) (Heteroptera: Rhopalidae: Serinethinae) Primera detección en Argentina y nuevos registros en Chile de Boisea trivittata (Say, 1825) (Heteroptera: Rhopalidae: Serinethinae)
No full textThe boxelder bug Boisea trivittata is reported for the first time from Argentina. Specimens were collected and observed in Godoy Cruz, Mendoza Province. Additionally, the first Chilean records from Maule Region are provided. The Maule localities are Curicó and Romeral; therefore, becoming the southernmost records in South America
Transformation of the Biocultural Heritage in the Chiloe Archipelago: A Globally Important Agricultural Heritage System
No full textPeasant family farming is characterized by its resilience to change, although it is exposed to drivers of socio-environmental transformation. We study the historical and contemporary drivers of change that have influenced the loss of biocultural heritage in the Rilán peninsula, a rural space in the Chiloe archipelago, in southern Chile that has been recognized by FAO as a Globally Important Agricultural Heritage System (GIAHS). Between September 2020 and October 2021, through a literature review, farm characterization sheets, and semi-structured interviews, eighteen family farms were visited, and individual conversations were held with a local historian and a rural extensionist in the agricultural field. The results show that, in the Chiloe archipelago, family farming continues to be a fundamental activity in terms of both identity and production, where, despite the changes in rural lifestyles in recent decades, a broad complex of knowledge, practices, and beliefs persists that have withstood rapid processes of agricultural modernization and multiple territorial transformations
Comparison of Postural Control of novice and expert rhythmic gymnasts Comparación del Control postural de gimnastas rítmicas novatas y expertas
No full textThe objective was to determine the differences in the quality of postural control between rhythmic gymnasts with differ-ent experience in performing skills specific to the discipline. The skills evaluated were Assisted Lateral Split (ELCA), Assisted Circle (CCA) and Unaided Back Split (EASA), considered those that generate the greatest muscle activation and changes in the center of pressure (CDP). The study involved 19 rhythmic gymnasts, 9 from the novice group (less than 4 years of experience), and 10 from the expert group (more than 4 years of experience). The execution of the sports skills was carried out on a force platform (model: BP5050. Bertec, USA), where the area and displacement speed of the center of pressure were evaluated. The area of displacement of the center of pressure was greater for all skill in novice gymnasts, compared to the experienced gymnasts, being statistically signifi-cant, in the ELCA skill. The skill that presented the greatest displacement of the center of pressure in novice gymnasts was ELCA, and for experts it was EASA. According to the results, experience influences better postural control, therefore we should start from an early age to focus on work aimed at improving this variable, allowing greater effectiveness and efficiency in this sport, optimizing the development of training and reducing the risk of injuries