Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.314
Filtrar
Más filtros

Intervalo de año de publicación
1.
Physiol Rev ; 104(3): 1387-1408, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38451234

RESUMEN

Effective data management is crucial for scientific integrity and reproducibility, a cornerstone of scientific progress. Well-organized and well-documented data enable validation and building on results. Data management encompasses activities including organization, documentation, storage, sharing, and preservation. Robust data management establishes credibility, fostering trust within the scientific community and benefiting researchers' careers. In experimental biomedicine, comprehensive data management is vital due to the typically intricate protocols, extensive metadata, and large datasets. Low-throughput experiments, in particular, require careful management to address variations and errors in protocols and raw data quality. Transparent and accountable research practices rely on accurate documentation of procedures, data collection, and analysis methods. Proper data management ensures long-term preservation and accessibility of valuable datasets. Well-managed data can be revisited, contributing to cumulative knowledge and potential new discoveries. Publicly funded research has an added responsibility for transparency, resource allocation, and avoiding redundancy. Meeting funding agency expectations increasingly requires rigorous methodologies, adherence to standards, comprehensive documentation, and widespread sharing of data, code, and other auxiliary resources. This review provides critical insights into raw and processed data, metadata, high-throughput versus low-throughput datasets, a common language for documentation, experimental and reporting guidelines, efficient data management systems, sharing practices, and relevant repositories. We systematically present available resources and optimal practices for wide use by experimental biomedical researchers.


Asunto(s)
Investigación Biomédica , Manejo de Datos , Difusión de la Información , Investigación Biomédica/normas , Investigación Biomédica/métodos , Difusión de la Información/métodos , Humanos , Animales , Manejo de Datos/métodos
2.
Nature ; 584(7819): 87-92, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32699412

RESUMEN

The initial colonization of the Americas remains a highly debated topic1, and the exact timing of the first arrivals is unknown. The earliest archaeological record of Mexico-which holds a key geographical position in the Americas-is poorly known and understudied. Historically, the region has remained on the periphery of research focused on the first American populations2. However, recent investigations provide reliable evidence of a human presence in the northwest region of Mexico3,4, the Chiapas Highlands5, Central Mexico6 and the Caribbean coast7-9 during the Late Pleistocene and Early Holocene epochs. Here we present results of recent excavations at Chiquihuite Cave-a high-altitude site in central-northern Mexico-that corroborate previous findings in the Americas10-17of cultural evidence that dates to the Last Glacial Maximum (26,500-19,000 years ago)18, and which push back dates for human dispersal to the region possibly as early as 33,000-31,000 years ago. The site yielded about 1,900 stone artefacts within a 3-m-deep stratified sequence, revealing a previously unknown lithic industry that underwent only minor changes over millennia. More than 50 radiocarbon and luminescence dates provide chronological control, and genetic, palaeoenvironmental and chemical data document the changing environments in which the occupants lived. Our results provide new evidence for the antiquity of humans in the Americas, illustrate the cultural diversity of the earliest dispersal groups (which predate those of the Clovis culture) and open new directions of research.


Asunto(s)
Migración Humana/historia , Cubierta de Hielo , Altitud , Arqueología , Teorema de Bayes , Cuevas , Diversidad Cultural , ADN Antiguo/análisis , Historia Antigua , Humanos , México
3.
Mol Psychiatry ; 29(3): 624-632, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38145984

RESUMEN

(R,S)-methadone ((R,S)-MTD) is a µ-opioid receptor (MOR) agonist comprised of (R)-MTD and (S)-MTD enantiomers. (S)-MTD is being developed as an antidepressant and is considered an N-methyl-D-aspartate receptor (NMDAR) antagonist. We compared the pharmacology of (R)-MTD and (S)-MTD and found they bind to MORs, but not NMDARs, and induce full analgesia. Unlike (R)-MTD, (S)-MTD was a weak reinforcer that failed to affect extracellular dopamine or induce locomotor stimulation. Furthermore, (S)-MTD antagonized motor and dopamine releasing effects of (R)-MTD. (S)-MTD acted as a partial agonist at MOR, with complete loss of efficacy at the MOR-galanin Gal1 receptor (Gal1R) heteromer, a key mediator of the dopaminergic effects of opioids. In sum, we report novel and unique pharmacodynamic properties of (S)-MTD that are relevant to its potential mechanism of action and therapeutic use. One-sentence summary: (S)-MTD, like (R)-MTD, binds to and activates MORs in vitro, but (S)-MTD antagonizes the MOR-Gal1R heteromer, decreasing its abuse liability.


Asunto(s)
Analgésicos Opioides , Metadona , Receptores Opioides mu , Receptores Opioides mu/metabolismo , Receptores Opioides mu/efectos de los fármacos , Animales , Metadona/farmacología , Masculino , Analgésicos Opioides/farmacología , Humanos , Ratones , Dopamina/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Ligandos , Estereoisomerismo
4.
PLoS Comput Biol ; 20(9): e1012489, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39348412

RESUMEN

Deep learning methods, trained on the increasing set of available protein 3D structures and sequences, have substantially impacted the protein modeling and design field. These advancements have facilitated the creation of novel proteins, or the optimization of existing ones designed for specific functions, such as binding a target protein. Despite the demonstrated potential of such approaches in designing general protein binders, their application in designing immunotherapeutics remains relatively underexplored. A relevant application is the design of T cell receptors (TCRs). Given the crucial role of T cells in mediating immune responses, redirecting these cells to tumor or infected target cells through the engineering of TCRs has shown promising results in treating diseases, especially cancer. However, the computational design of TCR interactions presents challenges for current physics-based methods, particularly due to the unique natural characteristics of these interfaces, such as low affinity and cross-reactivity. For this reason, in this study, we explored the potential of two structure-based deep learning protein design methods, ProteinMPNN and ESM-IF1, in designing fixed-backbone TCRs for binding target antigenic peptides presented by the MHC through different design scenarios. To evaluate TCR designs, we employed a comprehensive set of sequence- and structure-based metrics, highlighting the benefits of these methods in comparison to classical physics-based design methods and identifying deficiencies for improvement.


Asunto(s)
Biología Computacional , Aprendizaje Profundo , Receptores de Antígenos de Linfocitos T , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Antígenos de Linfocitos T/química , Receptores de Antígenos de Linfocitos T/metabolismo , Biología Computacional/métodos , Humanos , Ingeniería de Proteínas/métodos , Modelos Moleculares , Conformación Proteica , Unión Proteica
5.
Nucleic Acids Res ; 51(W1): W289-W297, 2023 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-37140050

RESUMEN

Molecular interactions that modulate catalytic processes occur mainly in cavities throughout the molecular surface. Such interactions occur with specific small molecules due to geometric and physicochemical complementarity with the receptor. In this scenario, we present KVFinder-web, an open-source web-based application of parKVFinder software for cavity detection and characterization of biomolecular structures. The KVFinder-web has two independent components: a RESTful web service and a web graphical portal. Our web service, KVFinder-web service, handles client requests, manages accepted jobs, and performs cavity detection and characterization on accepted jobs. Our graphical web portal, KVFinder-web portal, provides a simple and straightforward page for cavity analysis, which customizes detection parameters, submits jobs to the web service component, and displays cavities and characterizations. We provide a publicly available KVFinder-web at https://kvfinder-web.cnpem.br, running in a cloud environment as docker containers. Further, this deployment type allows KVFinder-web components to be configured locally and customized according to user demand. Hence, users may run jobs on a locally configured service or our public KVFinder-web.


Asunto(s)
Biología Computacional , Programas Informáticos , Biología Computacional/instrumentación , Biología Computacional/métodos , Internet , Interfaz Usuario-Computador
6.
J Proteome Res ; 23(6): 2148-2159, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38785273

RESUMEN

Diverse proteomics-based strategies have been applied to saliva to quantitatively identify diagnostic and prognostic targets for oral cancer. Considering that these targets may be regulated by events that do not imply variation in protein abundance levels, we hypothesized that changes in protein conformation can be associated with diagnosis and prognosis, revealing biological processes and novel targets of clinical relevance. For this, we employed limited proteolysis-mass spectrometry in saliva samples to explore structural alterations, comparing the proteome of healthy control and oral squamous cell carcinoma (OSCC) patients with and without lymph node metastasis. Thirty-six proteins with potential structural rearrangements were associated with clinical patient features including transketolase and its interacting partners. Moreover, N-glycosylated peptides contribute to structural rearrangements of potential diagnostic and prognostic markers. Altogether, this approach utilizes saliva proteins to search for targets for diagnosing and prognosing oral cancer and can guide the discovery of potential regulated sites beyond protein-level abundance.


Asunto(s)
Neoplasias de la Boca , Proteoma , Saliva , Humanos , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/patología , Neoplasias de la Boca/diagnóstico , Saliva/química , Saliva/metabolismo , Proteoma/análisis , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/diagnóstico , Femenino , Biomarcadores de Tumor/metabolismo , Masculino , Metástasis Linfática , Conformación Proteica , Persona de Mediana Edad , Pronóstico , Proteómica/métodos , Transcetolasa/metabolismo , Anciano , Espectrometría de Masas , Proteínas y Péptidos Salivales/metabolismo , Proteínas y Péptidos Salivales/análisis
7.
New Phytol ; 243(5): 2008-2020, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38952269

RESUMEN

The diversity of plant-pollinator interactions is grounded in floral resources, with nectar considered one of the main floral rewards plants produce for pollinators. However, a global evaluation of the number of animal-pollinated nectar-producing angiosperms and their distribution world-wide remains elusive. We compiled a thorough database encompassing 7621 plant species from 322 families to estimate the number and proportion of nectar-producing angiosperms reliant on animal pollination. Through extensive sampling of plant communities, we also explored the interplay between nectar production, floral resource diversity, latitudinal and elevational gradients, contemporary climate, and environmental characteristics. Roughly 223 308 animal-pollinated angiosperms are nectar-producing, accounting for 74.4% of biotic-pollinated species. Global distribution patterns of nectar-producing plants reveal a distinct trend along latitudinal and altitudinal gradients, with increased proportions of plants producing nectar in high latitudes and altitudes. Conversely, tropical communities in warm and moist climates exhibit greater floral resource diversity and a lower proportion of nectar-producing plants. These findings suggest that ecological trends driven by climate have fostered the diversification of floral resources in warmer and less seasonal climates, reducing the proportion of solely nectar-producing plants. Our study provides a baseline for understanding plant-pollinator relationships, plant diversification, and the distribution of plant traits.


Asunto(s)
Magnoliopsida , Néctar de las Plantas , Polinización , Néctar de las Plantas/metabolismo , Polinización/fisiología , Magnoliopsida/fisiología , Animales , Altitud , Flores/fisiología , Clima , Geografía
8.
Hepatology ; 77(4): 1319-1334, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36029129

RESUMEN

BACKGROUND AND AIMS: Receptor-interacting protein kinase 3 (RIPK3) mediates NAFLD progression, but its metabolic function is unclear. Here, we aimed to investigate the role of RIPK3 in modulating mitochondria function, coupled with lipid droplet (LD) architecture in NAFLD. APPROACH AND RESULTS: Functional studies evaluating mitochondria and LD biology were performed in wild-type (WT) and Ripk3-/- mice fed a choline-deficient, amino acid-defined (CDAA) diet for 32 and 66 weeks and in CRISPR-Cas9 Ripk3 -null fat-loaded immortalized hepatocytes. The association between hepatic perilipin (PLIN) 1 and 5, RIPK3, and disease severity was also addressed in a cohort of patients with NAFLD and in PLIN1 -associated familial partial lipodystrophy. Ripk3 deficiency rescued impairment in mitochondrial biogenesis, bioenergetics, and function in CDAA diet-fed mice and fat-loaded hepatocytes. Ripk3 deficiency was accompanied by a strong upregulation of antioxidant systems, leading to diminished oxidative stress upon fat loading both in vivo and in vitro. Strikingly, Ripk3-/- hepatocytes displayed smaller size LD in higher numbers than WT cells after incubation with free fatty acids. Ripk3 deficiency upregulated adipocyte and hepatic levels of LD-associated proteins PLIN1 and PLIN5. PLIN1 upregulation controlled LD structure and diminished mitochondrial stress upon free fatty acid overload in Ripk3-/- hepatocytes and was associated with diminished human NAFLD severity. Conversely, a pathogenic PLIN1 frameshift variant was associated with NAFLD and fibrosis, as well as with increased hepatic RIPK3 levels in familial partial lipodystrophy. CONCLUSIONS: Ripk3 deficiency restores mitochondria bioenergetics and impacts LD dynamics. RIPK3 inhibition is promising in ameliorating NAFLD.


Asunto(s)
Lipodistrofia Parcial Familiar , Enfermedad del Hígado Graso no Alcohólico , Humanos , Ratones , Animales , Enfermedad del Hígado Graso no Alcohólico/patología , Gotas Lipídicas , Lipodistrofia Parcial Familiar/metabolismo , Lipodistrofia Parcial Familiar/patología , Hígado/patología , Hepatocitos/metabolismo , Metabolismo Energético , Mitocondrias/metabolismo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo
9.
J Exp Bot ; 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39365061

RESUMEN

Resupination refers to the developmental orientation changes of flowers through ≈180º, leaving them effectively upside-down. It is a widespread trait present in 14 angiosperm families, including the Orchidaceae, where it is a gravitropic phenomenon actively controlled by auxins. Here, we demonstrate that the passive gravitational pull on flower parts can have an additional influence on resupination. We studied a lady's slipper orchid in which some flowers naturally fail to resupinate. We conducted a manipulative experiment removing floral parts and showed that both the probability of complete resupination and the degree of flower vertical movement (from 0º - 180º) are related to the mass of floral organs. During flower development, the tip of the ovary slightly curves actively (14.75º) due to gravitropism. This promotes a lever arm effect so that the gravitational pull acting on flower mass creates a torque that bends the ovary, orienting the flower into a resupinate position that is accessible to pollinators. The role of the mass of floral organs in resupination provides new insights into flower development and its role in pollination mechanisms.

10.
Eur J Clin Invest ; 54(3): e14128, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37975307

RESUMEN

INTRODUCTION: Diabetes mellitus (DM) impairs wound healing. The aim was to determine whether DM influences mitochondrial respiration in wounded skin (WS) and non-wounded skin (NWS), in a pre-clinical wound healing model of streptozotocin (STZ)-induced diabetes. METHODS: Six weeks after diabetes induction, two wounds were created in the back of C57BL/J6 mice. Using high-resolution respirometry (HRR), oxygen flux was measured, in WS and NWS, using two substrate-uncoupler-inhibitor titration protocols, at baseline (day 0), day 3 and 10 post-wounding, in STZ-DM and non-diabetic (NDM) mice. Flux control ratios for the oxidative phosphorylation (OXPHOS) capacity were calculated. RESULTS: A significant increase in mitochondrial respiration was observed in STZ-DM skin compared to control skin at baseline. The OXPHOS capacity was decreased in WS under diabetes at day 3 post-wounding (inflammation phase). However, at day 10 post-wounding (remodeling phase), the OXPHOS capacity was higher in WS from STZ-DM compared to NDM mice, and compared to NWS from STZ-DM mice. A significant relative contribution of pyruvate, malate and glutamate (PMG) oxidation to the OXPHOS capacity was observed in WS compared to NWS from STZ-DM mice, at day 10, while the relative contribution of fatty acid oxidation to the OXPHOS capacity was higher in NWS. The OXPHOS capacity is altered in WS from STZ-DM compared to NDM mice across the healing process, and so is the substrate contribution in WS and NWS from STZ-DM mice, at each time point. CONCLUSION: HRR may be a sensitive tool to evaluate the underlying mechanisms of tissue repair during wound healing.


Asunto(s)
Diabetes Mellitus Experimental , Fosforilación Oxidativa , Ratones , Animales , Diabetes Mellitus Experimental/metabolismo , Proyectos Piloto , Ratones Endogámicos C57BL , Piel/metabolismo
11.
J Exp Biol ; 227(19)2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39264243

RESUMEN

Testudines possess a rigid shell that influences the mechanics of the respiratory system. We studied respiratory mechanics in the terrestrial red-footed tortoise Chelonoidis carbonarius (Cryptodira), comparing juvenile individuals with a less ossified and more flexible carapace with adults with a well-ossified rigid shell. Combined with these ontogenetic differences, we analyzed respiratory system mechanics with animals in a supine and a prone position, as well as in the isolated lungs, to evaluate the impact of the viscera on breathing mechanics. To do so, we used established protocols to measure pulmonary volume (i.e. resting, VLr; and maximum, VLm), static (Cstat) and dynamic (Cdyn) compliance, and the work of breathing (W). We observed that isolated lungs displayed increased VLr, VLm, Cstat and Cdyn and decreased W. Additionally, pulmonary volume, compliance and W were affected by evaluated position, such as a smaller VLr in a supine position. Cdyn and W showed a volume dependency while frequency had less influence on these variables. At similar levels of ventilation, juveniles showed a lower W than adults when standardized by body mass, but similar W when standardized by VLr. Clear ontogenetic changes could be observed in breathing mechanics between juvenile and adult C. carbonarius. While these differences might largely be explained by variation in shell ossification, other explanations such as differences in visceral proportions or developmental degree of the post-pulmonary septum should also be taken into account.


Asunto(s)
Pulmón , Mecánica Respiratoria , Tortugas , Animales , Pulmón/fisiología , Pulmón/crecimiento & desarrollo , Tortugas/fisiología , Tortugas/crecimiento & desarrollo , Mecánica Respiratoria/fisiología , Masculino
12.
Curr Opin Urol ; 34(2): 58-63, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38168016

RESUMEN

PURPOSE OF REVIEW: Despite available treatments, many bladder pain syndrome/interstitial cystitis (BPS/IC) patients continue to have poor quality of life. Thus, there is an urge for new therapies. Our manuscript aims to review papers about BPS/IC treatments published in the last 2 years. RECENT FINDINGS: During this period, several treatments were tested, most of them new and others combining treatments already used. Pentosan polysulfate, interleukin 1 antagonist, low energy shock wave, physical therapy, hypnosis, acupuncture, clorpactin, dimethyl sulfoxide and hyaluronic acid plus botulinum toxin-A showed positive results. ASP3652 and lidocaine-releasing intravesical systems failed to prove their efficacy. SUMMARY: Validation of these studies is arduous due to the broad spectre of BPS/IC phenotypes, small number of patients enrolled, distinct outcome measures and short-term follow-up. It is also important to highlight that some authors combined therapies, and others split central and peripheric phenotypes before treatment. Therefore, soon, phenotyping and combining therapies with a step-by-step approach will be needed in BPS/IC treatment.


Asunto(s)
Toxinas Botulínicas Tipo A , Cistitis Intersticial , Humanos , Cistitis Intersticial/tratamiento farmacológico , Calidad de Vida , Administración Intravesical , Toxinas Botulínicas Tipo A/uso terapéutico , Lidocaína/uso terapéutico
13.
Environ Sci Technol ; 58(10): 4510-4521, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38426442

RESUMEN

Polystyrene (PS) is one of the main synthetic polymers produced around the world, and it is present in the composition of a wide variety of single-use objects. When released into the environment, these materials are degraded by environmental factors, resulting in microplastics. We investigated the ability of Chironomus sancticaroli (Diptera, Chironomidae) to promote the fragmentation of PS microspheres (24.5 ± 2.9 µm) and the toxic effects associated with exposure to this polymer. C. sancticaroli larvae were exposed to 3 different concentrations of PS (67.5, 135, and 270 particles g-1 of dry sediment) for 144 h. Significant lethality was observed only at the highest concentration. A significant reduction in PS particle size as well as evidence of deterioration on the surface of the spheres, such as grooves and cracks, was observed. In addition, changes in oxidative stress biomarkers (SOD, CAT, MDA, and GST) were also observed. This is the first study to report the ability of Chironomus sp. to promote the biofragmentation of microplastics. The information obtained demonstrates that the macroinvertebrate community can play a key role in the degradation of plastic particles present in the sediment of freshwater environments and can also be threatened by such particle pollution.


Asunto(s)
Chironomidae , Contaminantes Químicos del Agua , Animales , Microplásticos/toxicidad , Larva , Poliestirenos/toxicidad , Chironomidae/metabolismo , Plásticos/toxicidad , Contaminantes Químicos del Agua/análisis
14.
Phys Chem Chem Phys ; 26(15): 11436-11444, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38567569

RESUMEN

Bottom-up mechanochemical synthesis (BUMS) has been demonstrated to be an efficient approach for the preparation of metal nanoparticles (NPs), protected by surface agents or anchored on solid supports. However, there are limitations, such as precise size and morphological control, due to a lack of knowledge about the mechanically induced processes of NP formation under milling. In this article, we further investigate the BUMS of AuNPs. Using SiO2 as a solid support, we studied the effect of typical reducing agents, namely NaBH4, L-ascorbic acid, and hydroquinone (HQ), on the conversion of a AuIII source. XANES showed that HQ is the strongest reducing agent under our experimental conditions, leading to the quantitative conversion of gold salt in a few minutes. Interestingly, even when HQ was used in sub-stoichiometric amounts, AuIII could be reduced to ratios higher than 85% after two minutes of milling. Investigations into the byproducts by 1H NMR and GC-FID/MS enabled the identification HQ regeneration and the formation of its derivatives. We mainly focused on benzoquinone (BQ), which is the product of the oxidation of HQ as it reduces the gold salt. We could demonstrate that HQ is regenerated from BQ exclusively under milling and acidic conditions. The regenerated HQ and other HQ-chlorinated molecules could then reduce gold-oxidized species, leading to higher conversions and economy of reactants. Our study highlights the intriguing and complex mechanisms of mechanochemical systems, in addition to fostering the atom and energy economy side of mechanochemical means to produce metal nanoparticles.

15.
Sensors (Basel) ; 24(7)2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38610305

RESUMEN

The flexibility and versatility associated with autonomous mobile robots (AMR) have facilitated their integration into different types of industries and tasks. However, as the main objective of their implementation on the factory floor is to optimize processes and, consequently, the time associated with them, it is necessary to take into account the environment and congestion to which they are subjected. Localization, on the shop floor and in real time, is an important requirement to optimize the AMRs' trajectory management, thus avoiding livelocks and deadlocks during their movements in partnership with manual forklift operators and logistic trains. Threeof the most commonly used localization techniques in indoor environments (time of flight, angle of arrival, and time difference of arrival), as well as two of the most commonly used indoor localization methods in the industry (ultra-wideband, and ultrasound), are presented and compared in this paper. Furthermore, it identifies and compares three industrial indoor localization solutions: Qorvo, Eliko Kio, and Marvelmind, implemented in an industrial mobile platform, which is the main contribution of this paper. These solutions can be applied to both AMRs and other mobile platforms, such as forklifts and logistic trains. In terms of results, the Marvelmind system, which uses an ultrasound method, was the best solution.

16.
Sensors (Basel) ; 24(17)2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39275600

RESUMEN

Cervical pain has been linked to increased motor unit activity, potentially associated with the initiation and progression of chronic neck pain. Therefore, this study aimed to compare the time-course changes in cervical superficial muscle activation patterns among dental students with and without neck pain throughout their initial semester of clinical training. We used an online Nordic Musculoskeletal Questionnaire for group allocation between neck pain (NP) (n = 21) and control group (CG) (n = 23). Surface electromyography (sEMG) of the sternocleidomastoid and upper bilateral trapezius was recorded before starting their clinical practice and after their first semester while performing a cranio-cervical flexion test (CCFT) in five increasing levels between 22 mmHg and 30 mmHg. After the first semester, both the CG (p < 0.001) and NP (p = 0.038) groups showed decreased sternocleidomastoid activation. The NP group exhibited a concomitant increase in upper trapezius coactivation (p < 0.001), whereas the muscle activation pattern in asymptomatic students remained unchanged (p = 0.980). During the first semester of clinical training, dental students exhibited decreased superficial flexor activity, but those with neck pain had increased co-contraction of the upper trapezius, likely to stabilize the painful segment. This altered activation pattern could be associated with further dysfunction and symptoms, potentially contributing to chronicity.


Asunto(s)
Electromiografía , Músculos del Cuello , Dolor de Cuello , Estudiantes de Odontología , Humanos , Músculos del Cuello/fisiología , Masculino , Femenino , Dolor de Cuello/fisiopatología , Estudios Longitudinales , Adulto Joven , Adulto , Encuestas y Cuestionarios
17.
J Fish Biol ; 104(4): 1112-1121, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38174622

RESUMEN

The yellowfin tuna is a very abundant tropical tuna species in the western equatorial Atlantic Ocean and an important fishery resource for the Brazilian tuna fleet. In this study we performed stable isotope analysis to better understand the spatial trophodynamics and dietary changes in yellowfin tuna around two insular marine protected areas in Brazil. A total of 65 yellowfin tuna specimens measuring between 47 and 138 cm LT (total length) were sampled around the archipelagos of Fernando de Noronha (FNA; n = 34) and Saint Peter and Saint Paul (SPSPA; n = 31) between July 2018 and September 2019. Bayesian mixing models and generalized additive models were used to investigate the contributions of four different prey items (zooplankton, cephalopods, fish larvae, and flying fish) to yellowfin tuna diet in each area and their potential changes in relation to predator growth. The four prey items were found to have different overall contributions between the two studied areas, with zooplankton being the most important prey in FNA, whereas flying fish was the most relevant prey to the species' diet in SPSPA. Significant changes in the species diet by size were also found, with fish smaller than 90 cm (TL) having a more generalist diet and larger animals relying more on consuming larger and more nutritious prey (i.e., flying fish). Our results suggest that these two marine protected areas play an important role in ocean dynamics, providing important and different foraging grounds for the development of this predator species.


Asunto(s)
Corteza Insular , Atún , Animales , Teorema de Bayes , Océano Atlántico , Peces , Conducta Alimentaria , Océano Pacífico
18.
J Fish Biol ; 104(5): 1290-1298, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38299718

RESUMEN

This study delves into the foraging ecology of the cookiecutter shark (Isistius brasiliensis) in the Saint Peter and Saint Paul Archipelago (SPSPA), assessing bite marks on pelagic fishes collected between March and September 2018. Examination of 200 individuals from five species revealed the shark's predilection for targeting adult fish, ensuring efficient removal of energy-rich tissue layers. However, a notable exception is Thunnus albacares, preyed on predominantly during its juvenile stage, possibly due to vertical spatial segregation. Recent bites were pervasive across species, with wahoo displaying a distinctive pattern. Cookiecutter shark bites predominantly targeted the lateral body portion (>55%) except for yellowfin tuna, which exhibited a preference for the ventral region (95%). The estimated length distribution suggests the SPSPA as a potential nursery area for cookiecutter sharks. Bite mark positions and frequencies may be linked to fish behavior, swimming velocity, and fishing gear strategy, highlighting the complex interplay in pelagic ecosystems.


Asunto(s)
Conducta Alimentaria , Conducta Predatoria , Tiburones , Animales , Tiburones/fisiología , Océano Atlántico
19.
J Esthet Restor Dent ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39228147

RESUMEN

OBJECTIVE: The purpose of this in vitro study was to evaluate the effect of staining, glazing, and polishing on the survival probability of monolithic crowns manufactured with preshaded stabilized zirconia with 5 mol% of yttrium oxide (5Y-TZP). MATERIALS AND METHODS: Monolithic crowns in the shape of an upper canine (1.5 mm of thickness) were manufactured by CAD/CAM, adhesively cemented on metallic foundation, and divided into 6 groups (n = 21): C (control), S (staining), G (glazing), P (polishing), SG (staining and glazing), and SP (staining and polishing). The survival probability was determined by step-stress accelerated life testing with a load applied to the palatine concavity of the crown. First, the specimens were subjected to a single-load to fracture test (SLF) and next to the fatigue test (5 Hz, thermocycling immersed in water varying 5-55°C), including the light (n = 9), moderate (n = 6), and aggressive (n = 3) loading profiles (load ranged between 20% and 60% of SLF). The survival probability was calculated considering the cycles for failure (CFF) and fatigue failure load (FFL) and illustrated using a Kaplan-Meier graph. The comparison among groups was performed using a Log-Rank test (α = 0.05). RESULTS: The mean value of SLF was 586.7 N. There was no difference among groups in survival probability, considering CFF and FFL. CONCLUSION: Staining, glazing, and polishing can be performed safely without damaging the mechanical behavior of 5Y-TZP monolithic crowns. CLINICAL SIGNIFICANCE: Staining is used to characterize and improve the esthetic of zirconia monolithic crowns. It can be used to reproduce the color gradient in the cervical region of the crown and pigmented grooves. This study showed that staining, glazing, and polishing did not affect the survival probability and the use of finishing procedures (glazing or polishing) after staining did not improve the survival probability of zirconia monolithic crowns.

20.
Artículo en Inglés | MEDLINE | ID: mdl-39480362

RESUMEN

OBJECTIVE: The aim of this study was to systematically review the influence of the intrinsic foot musculature on lower limb injuries, with regard to improving foot posture and self-reported function, and to point out the biomechanical effects of strengthening the intrinsic foot musculature. METHODS: A comprehensive literature search using National Library of Medicine (Medline-PubMed), Scopus, Web of Science, Pedro, SportDiscus, and Cochrane was undertaken. SELECTION CRITERIA: A literature search was peformed using: Clinical trials of patients with injuries in the lower limbs, and with alterations in the intrinsic musculature of the foot were included and published in the period up to and including April 2023. DATA SYNTHESIS: Data analysis was measured as standardized mean difference and confidence interval was set at 95%. Random effects model was used. RESULTS: A total of 1,051 studies were found, but, after evaluation, only 4 were included in the present study. The effect of intrinsic foot musculature strengthening improved medial longitudinal arch height in studies included in the meta-analysis (P < .00001). CONCLUSION: Based on this systematic review, it is possible to conclude that increasing the strength of intrinsic foot muscles proved to be effective in promoting positive biomechanical changes in the longitudinal arch of the foot of these patients.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA