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1.
Infect Dis (Lond) ; : 1-13, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39046827

RESUMO

BACKGROUND: To infer a reliable SARS-CoV-2 antibody protection level from a serological test, an appropriate quantitative threshold and solid equivalence across serological tests are needed. Additionally, tests should show a solid correlation with neutralising assays and with the protection observed in large population cohorts even against emerging variants. OBJECTIVES: We studied convalescent and vaccinated populations using 11 commercial antibody assays. Results were compared to evaluate discrepancies across tests. Neutralisation capacity was measured in a subset of the samples with a lentiviral-based assay. METHODS: Serum from convalescent (n = 121) and vaccinated individuals (n = 471, 260 with Comirnaty, 110 with Spikevax, and 96 with Vaxzevria) was assessed using 11 different assays, including two from Abbott, Euroimmun, Liaison, Roche, and Vircell, and one from Siemens. A spike protein-lentiviral vector with a fluorescent reporter was used for neutralisation assay of serum from convalescent (n = 26) and vaccinated (n = 39) individuals. RESULTS: Positivity ranged between 81.3 and 94.3% after infection and 99.4 and 99.7% after vaccination, depending on the assay. Both cohorts showed a high level of qualitative agreement across tests (Fleiss' kappa = 0.598 and 0.719 for convalescent and vaccinated respectively). Spikevax vaccine recipients showed the highest level of antibodies in all tests. Effectiveness of each test predicting SARS-CoV-2 neutralising capacity depended on assay type and target, with CLIA and anti-S being more effective than ELISA and anti-N assays, respectively. CONCLUSIONS: High-throughput immunoassays are good predictors of neutralising capacity. Updated targets and better standardisation would be required to find an effective correlate of protection, especially to account for antibodies against new variants.

2.
Behav Brain Res ; 471: 115095, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38857705

RESUMO

Several studies indicate that some cognitive changes occur after COVID-19. Visuospatial alterations have been reported in 24-40 %. These alterations may be useful as early biomarkers of neurodegenerative disease. Thus, we can emphasize the importance of visuospatial processes in cognition through quantitative and qualitative analysis of performance on the Clock Test (CDT) and the Rey-Osterrieth Complex Figure (FCRO). Our objective was to describe the performance of post COVID 19 patients in visuospatial tests, with different degrees of respiratory impairment and to perform a qualitative analysis of the performance to check its relationship with alterations in attention and executive functions. This will allow highlighting the executive component of the performance of the CDT and ROCF and differentiate patients with possible cognitive impairment. 77 patients with SARS-CoV-2 infection were evaluated (3 months post-infection) with a complete neuropsychological battery and MRI. Overall, there is a significant difference between FCRO and CDT, with FCRO having only 9 % change and CDT having 51.9 % change. Regarding the correlations observed between groups (VM Inv, VM non I and non hospitalized) the highest correlations were observed between Boston with FCRO copy (r=0.497; p=0.001) and with FCRO memory (r=0.429; p=0.001). Comparing the performance between groups by severity, significant differences were observed only in the TMT A (13.706 p=0.001) and B (9.583 p=0.008) tests and in the phonological fluency letter A (13.445 p=0.001), we observed that the group of non-hospitalized patients had a better performance. Neuropsychological deficits often have a direct impact on daily life by affecting the ability to learn and adapt. Thus, a useful strategy for the neuropsychological characterization of post-COVID-19 patients is the qualitative analysis of visuospatial abilities in conjunction with executive functions that cannot be analyzed in isolation.

3.
Int J Mol Sci ; 25(9)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38732093

RESUMO

The chromatin organization and its dynamic remodeling determine its accessibility and sensitivity to DNA damage oxidative stress, the main source of endogenous DNA damage. We studied the role of the VRK1 chromatin kinase in the response to oxidative stress. which alters the nuclear pattern of histone epigenetic modifications and phosphoproteome pathways. The early effect of oxidative stress on chromatin was studied by determining the levels of 8-oxoG lesions and the alteration of the epigenetic modification of histones. Oxidative stress caused an accumulation of 8-oxoG DNA lesions that were increased by VRK1 depletion, causing a significant accumulation of DNA strand breaks detected by labeling free 3'-DNA ends. In addition, oxidative stress altered the pattern of chromatin epigenetic marks and the nuclear phosphoproteome pathways that were impaired by VRK1 depletion. Oxidative stress induced the acetylation of H4K16ac and H3K9 and the loss of H3K4me3. The depletion of VRK1 altered all these modifications induced by oxidative stress and resulted in losses of H4K16ac and H3K9ac and increases in the H3K9me3 and H3K4me3 levels. All these changes were induced by the oxidative stress in the epigenetic pattern of histones and impaired by VRK1 depletion, indicating that VRK1 plays a major role in the functional reorganization of chromatin in the response to oxidative stress. The analysis of the nuclear phosphoproteome in response to oxidative stress detected an enrichment of the phosphorylated proteins associated with the chromosome organization and chromatin remodeling pathways, which were significantly decreased by VRK1 depletion. VRK1 depletion alters the histone epigenetic pattern and nuclear phosphoproteome pathways in response to oxidative stress. The enzymes performing post-translational epigenetic modifications are potential targets in synthetic lethality strategies for cancer therapies.


Assuntos
Epigênese Genética , Histonas , Estresse Oxidativo , Proteínas Serina-Treonina Quinases , Humanos , Histonas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteoma/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , Dano ao DNA , Núcleo Celular/metabolismo , Cromatina/metabolismo , Cromatina/genética , Linhagem Celular Tumoral , Acetilação , Processamento de Proteína Pós-Traducional
4.
Sci Total Environ ; 931: 172913, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38697521

RESUMO

This study examines the influence of meteorological factors and air pollutants on the performance of automatic pollen monitoring devices, as part of the EUMETNET Autopollen COST ADOPT-intercomparison campaign held in Munich, Germany, during the 2021 pollen season. The campaign offered a unique opportunity to compare all automatic monitors available at the time, a Plair Rapid-E, a Hund-Wetzlar BAA500, an OPC Alphasense, a KH-3000 Yamatronics, three Swisens Polenos, a PollenSense APS, a FLIR IBAC2, a DMT WIBS-5, an Aerotape Sextant, to the average of four manual Hirst traps, under the same environmental conditions. The investigation aimed to elucidate how meteorological factors and air pollution impact particle capture and identification efficiency. The analysis showed coherent results for most devices regarding the correlation between environmental conditions and pollen concentrations. This reflects on one hand, a significant correlation between weather and airborne pollen concentration, and on the other hand the capability of devices to provide meaningful data under the conditions under which measurements were taken. However, correlation strength varied among devices, reflecting differences in design, algorithms, or sensors used. Additionally, it was observed that different algorithms applied to the same dataset resulted in different concentration outputs, highlighting the role of algorithm design in these systems (monitor + algorithm). Notably, no significant influence from air pollutants on the pollen concentrations was observed, suggesting that any potential difference in effect on the systems might require higher air pollution concentrations or more complex interactions. However, results from some monitors were affected to a minor degree by specific weather variables. Our findings suggest that the application of real-time devices in urban environments should focus on the associated algorithm that classifies pollen taxa. The impact of air pollution, although not to be excluded, is of secondary concern as long as the pollution levels are similar to a large European city like Munich.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Monitoramento Ambiental , Pólen , Monitoramento Ambiental/métodos , Poluentes Atmosféricos/análise , Alemanha , Poluição do Ar/estatística & dados numéricos , Poluição do Ar/análise , Tempo (Meteorologia)
5.
J Physiol ; 602(10): 2227-2251, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38690610

RESUMO

Passive whole-body hyperthermia increases limb blood flow and cardiac output ( Q ̇ $\dot Q$ ), but the interplay between peripheral and central thermo-haemodynamic mechanisms remains unclear. Here we tested the hypothesis that local hyperthermia-induced alterations in peripheral blood flow and blood kinetic energy modulate flow to the heart and Q ̇ $\dot Q$ . Body temperatures, regional (leg, arm, head) and systemic haemodynamics, and left ventricular (LV) volumes and functions were assessed in eight healthy males during: (1) 3 h control (normothermic condition); (2) 3 h of single-leg heating; (3) 3 h of two-leg heating; and (4) 2.5 h of whole-body heating. Leg, forearm, and extracranial blood flow increased in close association with local rises in temperature while brain perfusion remained unchanged. Increases in blood velocity with small to no changes in the conduit artery diameter underpinned the augmented limb and extracranial perfusion. In all heating conditions, Q ̇ $\dot Q$ increased in association with proportional elevations in systemic vascular conductance, related to enhanced blood flow, blood velocity, vascular conductance and kinetic energy in the limbs and head (all R2 ≥ 0.803; P < 0.001), but not in the brain. LV systolic (end-systolic elastance and twist) and diastolic functional profiles (untwisting rate), pulmonary ventilation and systemic aerobic metabolism were only altered in whole-body heating. These findings substantiate the idea that local hyperthermia-induced selective alterations in peripheral blood flow modulate the magnitude of flow to the heart and Q ̇ $\dot Q$ through changes in blood velocity and kinetic energy. Localised heat-activated events in the peripheral circulation therefore affect the human heart's output. KEY POINTS: Local and whole-body hyperthermia increases limb and systemic perfusion, but the underlying peripheral and central heat-sensitive mechanisms are not fully established. Here we investigated the regional (leg, arm and head) and systemic haemodynamics (cardiac output: Q ̇ $\dot Q$ ) during passive single-leg, two-leg and whole-body hyperthermia to determine the contribution of peripheral and central thermosensitive factors in the control of human circulation. Single-leg, two-leg, and whole-body hyperthermia induced graded increases in leg blood flow and Q ̇ $\dot Q$ . Brain blood flow, however, remained unchanged in all conditions. Ventilation, extracranial blood flow and cardiac systolic and diastolic functions only increased during whole-body hyperthermia. The augmented Q ̇ $\dot Q$ with hyperthermia was tightly related to increased limb and head blood velocity, flow and kinetic energy. The findings indicate that local thermosensitive mechanisms modulate regional blood velocity, flow and kinetic energy, thereby controlling the magnitude of flow to the heart and thus the coupling of peripheral and central circulation during hyperthermia.


Assuntos
Débito Cardíaco , Hipertermia , Humanos , Masculino , Adulto , Hipertermia/fisiopatologia , Débito Cardíaco/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Febre/fisiopatologia , Adulto Jovem , Temperatura Alta , Hemodinâmica
6.
Digit Health ; 10: 20552076241239274, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38559583

RESUMO

Objectives: Metabolic bariatric surgery is a critical intervention for patients living with obesity and related health issues. Accurate classification and prediction of patient outcomes are vital for optimizing treatment strategies. This study presents a novel machine learning approach to classify patients in the context of metabolic bariatric surgery, providing insights into the efficacy of different models and variable types. Methods: Various machine learning models, including Gaussian Naive Bayes, Complement Naive Bayes, K-nearest neighbour, Decision Tree, K-nearest neighbour with RandomOverSampler, and K-nearest neighbour with SMOTE, were applied to a dataset of 73 patients. The dataset, comprising psychometric, socioeconomic, and analytical variables, was analyzed to determine the most efficient predictive model. The study also explored the impact of different variable groupings and oversampling techniques. Results: Experimental results indicate average accuracy values as high as 66.7% for the best model. Enhanced versions of K-nearest neighbour and Decision Tree, along with variations of K-nearest neighbour such as RandomOverSampler and SMOTE, yielded the best results. Conclusions: The study unveils a promising avenue for classifying patients in the realm of metabolic bariatric surgery. The results underscore the importance of selecting appropriate variables and employing diverse approaches to achieve optimal performance. The developed system holds potential as a tool to assist healthcare professionals in decision-making, thereby enhancing metabolic bariatric surgery outcomes. These findings lay the groundwork for future collaboration between hospitals and healthcare entities to improve patient care through the utilization of machine learning algorithms. Moreover, the findings suggest room for improvement, potentially achievable with a larger dataset and careful parameter tuning.

7.
BMC Public Health ; 24(1): 790, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38481210

RESUMO

BACKGROUND: Significant consequences of COVID-19 within academic/professional life are, at the psychological level, related to worry, tension, stress; coping strategies and lifestyle changes. This study describes the process of design and validation of an inventory (QPIC), which aims to assess the psychological impact that a situation of confinement can produce among university students and teachers. METHODS: Design of the instrument and psychometric tests. A sample of 862 students and 229 professors affiliated to Spanish and Colombian universities was used. Data were collected in April 2020 with the request of the favourable Bioethics Committee IR/2020. RESULTS: Six experts carried out the content validation. A confirmatory factor analysis of the theoretical dimensions proposed for the scales was performed and the internal consistency of each of the three initial scales was confirmed (0.866, 0.813 and 0.834). CONCLUSION: A rigorous and reliable instrument is achieved, consisting of two final scales: (a) Worry, tension and stress scale (b) Coping scale, which helps to measure individual psychological effects in housebound situations. It is an instrument designed, constructed ad hoc to assess the impact of confinement and subjected to validation. The factor structure and reliability of the instrument are examined and good psychometric properties are obtained. The application of this inventory will make it possible to assess the impact on people's mental health during a period of confinement.


Assuntos
COVID-19 , Saúde Mental , Humanos , Universidades , Reprodutibilidade dos Testes , Ansiedade , COVID-19/epidemiologia , Psicometria , Inquéritos e Questionários
8.
Foot Ankle Surg ; 30(4): 275-284, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38388212

RESUMO

BACKGROUND: Main objective of this research is to know if there is a different survival rate between fixed bearing (FB) and mobile bearing (MB) total ankle replacement (TAR). We hypothesized that there are no differences between the survival rates of both implants. METHODS: A systematic search was performed in PubMed, Cochrane, EMBASE and ClinicalTrials.gov databases to identify published studies from August 2018 to September 2022 including results for FB and MB TAR survivorship. Inclusion criteria included 1) primary TAR in one or both feet in which implant could be identified , 2) a minimum of 20 procedures reported, 3) reported implant survivorship or calculable and 4) a minimum of 12 months follow-up for level 1-3 studies or 60 months for level 4 studies. RESULTS: 3902 ankles in 28 studies were included. 719 were FB and 3104 MB with an overall survivorship of 94% (95% CI [0.89; 0.97]) and 89% (95% CI [0.86; 0.92]) respectively. After subgroup analysis, we did not find differences among both groups (p =  0.429 ). Meta-regression analysis showed that longer follow-up was associated with lower survival rates in MB group (p = 0.000) while no other relationships were found with other factors (age, level of evidence or conflict of interests). CONCLUSIONS: No differences in survival rates between both groups were found. Age and other studied confounders were not found to be related with implant survivorship. However, longer follow-up was found to be related with lower survival rates. Studies with longer follow-up and higher level of evidence are needed to confirm results. LEVEL OF EVIDENCE: IV, systematic review of level I to IV studies.


Assuntos
Artroplastia de Substituição do Tornozelo , Prótese Articular , Falha de Prótese , Humanos , Artroplastia de Substituição do Tornozelo/instrumentação , Desenho de Prótese , Articulação do Tornozelo/cirurgia
9.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38403112

RESUMO

Calcaneal articular fractures are fractures classically associated with a high rate of complications and poor outcomes. Osteosynthesis of the calcaneus through a sinus tarsi approach has shown results equal to or superior to those of the extended approach, having become the new gold standard. The objective of this article is to detail step by step the surgical technique of osteosynthesis of intra-articular fractures of the calcaneus through a sinus tarsi approach, from the selection of the fracture, positioning of the patient, layout of the operating room and the fluoroscope, the entire surgical process until postoperative treatment. The surgical technique described below is described in 6 steps. Anatomical reduction of complex calcaneal fractures through an Sinus Tarsi Approach requires an understanding of the fracture and its associated deformities. Following the described sequence step by step will help to achieve a better reduction in order to achieve better functional results.

10.
Exp Physiol ; 109(4): 600-613, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38230961

RESUMO

A positive relationship between local tissue temperature and perfusion exists, with isolated limb-segment hyperthermia stimulating hyperaemia in the heated region without affecting the adjacent, non-heated limb segment. However, whether partial-limb segment heating evokes a heightened tissue perfusion in the heated region without directly or reflexly affecting the non-heated tissues of the same limb segment remains unknown. This study investigated, in 11 healthy young adults, the lower limb temperature and haemodynamic responses to three levels of 1 h upper-leg heating, none of which alter core temperature: (1) whole-thigh (WTH; water-perfused garment), (2) quadriceps (QH; water-perfused garment) and (3) partial-quadriceps (PQH; pulsed shortwave diathermy) heating. It was hypothesised that perfusion would only increase in the heated regions. WTH, QH and PQH increased local heated tissue temperature by 2.9 ± 0.6, 2.0 ± 0.7 and 2.9 ± 1.3°C (P < 0.0001), respectively, whilst remaining unchanged in the non-heated hamstrings and quadriceps tissues during QH and PQH. WTH induced a two-fold increase in common femoral artery blood flow (P < 0.0001) whereas QH and PQH evoked a similar ∼1.4-fold elevation (P ≤ 0.0018). During QH and PQH, however, tissue oxygen saturation and laser-Doppler skin blood flow in the adjacent non-heated hamstrings or quadriceps tissues remained stable (P > 0.5000). These findings in healthy young humans demonstrate a tight thermo-haemodynamic coupling during regional thigh heating, providing further evidence of the importance of local heat-activated mechanisms on the control of blood circulation.


Assuntos
Hipertermia Induzida , Coxa da Perna , Adulto Jovem , Humanos , Calefação , Fluxo Sanguíneo Regional/fisiologia , Extremidade Inferior , Hemodinâmica , Temperatura Alta , Água
11.
Vet Rec ; 194(3): e3667, 2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38012019

RESUMO

BACKGROUND: The identification of ophthalmic diseases that affect vision and/or cause discomfort should be a priority in captive penguins to improve their overall health and quality of life. METHODS: A routine ophthalmological examination was performed on 80 clinically normal penguins (160 eyes), and any lesions observed were recorded. RESULTS: Ocular lesions were frequent (56% of penguins), with cataracts being the most common (48.8% of penguins). Cortical cataracts (63% of eyes) and posterior subcapsular cataracts (27.4%) were the most commonly occurring. All maturation stages were found; incipient cataracts (52.1% of eyes with cataracts) were predominant, while Morgagnian cataracts (8.2%) were the least frequent. A correlation existed between lenticular changes and increasing age. Uveitis was present in 43.8% of eyes with cataracts, and ectropion uveae was the predominant clinical sign. Other ocular findings included blepharitis (3.8% of all eyes), corneal leukoma (5.6%) and posterior lens subluxation (7.5%). LIMITATIONS: The small number of birds of some species prevented the comparison of ophthalmic findings between species. CONCLUSION: This study corroborates the high prevalence of ocular lesions in captive penguins. Cataracts were frequent and age related. Most cataracts were cortical, and the predominant maturation stage was incipient. Lens-induced uveitis was a common finding. Lowered intraocular pressure was related to cataract formation.


Assuntos
Catarata , Spheniscidae , Uveíte , Animais , Qualidade de Vida , Catarata/veterinária , Catarata/patologia , Olho , Uveíte/veterinária
12.
Int J Food Microbiol ; 411: 110522, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38160537

RESUMO

Type 3 sourdoughs, which are starter culture-initiated and subsequently backslopped, are less studied than other sourdough types. Yet, they can serve as a model to assess how competitive starter culture strains for sourdough production are and how the microbial composition of such sourdoughs may evolve over time. In the present study, Limosilactobacillus fermentum IMDO 130101 was used to produce Type 3 sourdoughs, prepared from wheat and wholemeal wheat flours. Therefore, an initial fermentation of the flour-water mixture was performed at 30 °C for 48 h. This was followed by cold storage-backslopping cycles, consisting of refreshments (50 %, v/v), fermentation steps of 16 h, and storage at 4 °C each week, every three weeks, and every six weeks. The microbial dynamics (culture-dependent and -independent approaches) and metabolite dynamics were measured. In all sourdoughs produced, starter culture strain monitoring, following an amplicon sequence variant approach, showed that Liml. fermentum IMDO 130101 prevailed during one month when the sourdoughs were refreshed each week, during 24 weeks when the sourdoughs were refreshed every three weeks, and during 12 weeks when the sourdoughs were refreshed every six weeks. This suggested the competitiveness and robustness of Liml. fermentum IMDO 130101 for a considerable duration but also showed that the strain is prone to microbial interference. For instance, Levilactobacillus brevis and Pediococcus spp. prevailed upon further cold storage and backslopping. Also, although no yeasts were inoculated into the flour-water mixtures, Kazachstania unispora, Torulaspora delbrueckii, and Wickerhamomyces anomalus were the main yeast species found. They appeared after several weeks of storage and backslopping, which however indicated the importance of an interplay between LAB and yeast species in sourdoughs. The main differences among the mature sourdoughs obtained could be explained by the different flours used, the refreshment conditions applied, and the sampling time (before and after backslopping). Finally, the metabolite quantifications revealed continued metabolite production during the cold storage periods, which may impact the sourdough properties and those of the breads made thereof.


Assuntos
Limosilactobacillus fermentum , Torulaspora , Pediococcus , Pão , Farinha , Fermentação , Água
13.
Foot Ankle Orthop ; 8(4): 24730114231213594, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38058977

RESUMO

Background: The aim of this study was to translate and cross-culturally adapt the Olerud-Molander Ankle Score (OMAS) into Spanish and to assess its reliability and validity. Methods: The translation and adaptation to develop the Spanish version of the OMAS (OMAS-Sp) was performed according to current international guidelines. The OMAS-Sp was administered to 98 patients with a surgically treated ankle fracture, and it was repeated 7-14 days later to assess construct reliability of each question's score and the total score. Test-retest reliability and the internal consistency were calculated, and concurrent validity was assessed by comparing the OMAS-Sp with the Foot and Ankle Outcome Score (FAOS). The presence of floor and ceiling effects was also analyzed. Results: Adequate internal consistency was found with a Cronbach α of 0.821. Excellent test-retest reliability was demonstrated with an interclass correlation coefficient for the total score of 0.970 (95% CI 0.956-0.980; P < .001). Spearman correlation coefficients (r's) between the OMAS-Sp total score and the 5 FAOS subscales ranged from 0.944 to 0.951 (P < .001). No floor or ceiling effects were found. Conclusion: The OMAS-Sp demonstrated adequate psychometric properties and is a valid and reliable tool for assessing outcomes in Spanish-speaking patients with surgically treated ankle fractures. Level of Evidence: Level II, prospective cohort study.

14.
Exp Physiol ; 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38126953

RESUMO

Circulation of the blood is a fundamental physiological function traditionally ascribed to the pressure-generating function of the heart. However, over the past century the 'cardiocentric' view has been challenged by August Krogh, Ernst Starling, Arthur Guyton and others, based on haemodynamic data obtained from isolated heart preparations and organ perfusion. Their research brought forth experimental evidence and phenomenological observations supporting the concept that cardiac output occurs primarily in response to the metabolic demands of the tissues. The basic tenets of Guyton's venous return model are presented and juxtaposed with their critiques. Developmental biology of the cardiovascular system shows that the blood circulates before the heart has achieved functional integrity and that its movement is intricately connected with the metabolic demands of the tissues. Long discovered, but as yet overlooked, negative interstitial pressure may play a role in assisting the flow returning to the heart. Based on these phenomena, an alternative circulation model has been proposed in which the heart functions like a hydraulic ram and maintains a dynamic equilibrium between the arterial (centrifugal) and venous (centripetal) forces which define the blood's circular movement. In this focused review we introduce some of the salient arguments in support of the proposed circulation model. Finally, we present evidence that exercising muscle blood flow is subject to local metabolic control which upholds optimal perfusion in the face of a substantive rise in muscle vascular conductance, thus lending further support to the permissive role of the heart in the overall control of blood circulation.

16.
Sci Data ; 10(1): 648, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37737210

RESUMO

Human activity recognition and clinical biomechanics are challenging problems in physical telerehabilitation medicine. However, most publicly available datasets on human body movements cannot be used to study both problems in an out-of-the-lab movement acquisition setting. The objective of the VIDIMU dataset is to pave the way towards affordable patient gross motor tracking solutions for daily life activities recognition and kinematic analysis. The dataset includes 13 activities registered using a commodity camera and five inertial sensors. The video recordings were acquired in 54 subjects, of which 16 also had simultaneous recordings of inertial sensors. The novelty of dataset lies in: (i) the clinical relevance of the chosen movements, (ii) the combined utilization of affordable video and custom sensors, and (iii) the implementation of state-of-the-art tools for multimodal data processing of 3D body pose tracking and motion reconstruction in a musculoskeletal model from inertial data. The validation confirms that a minimally disturbing acquisition protocol, performed according to real-life conditions can provide a comprehensive picture of human joint angles during daily life activities.


Assuntos
Atividades Cotidianas , Movimento , Humanos , Fenômenos Biomecânicos , Relevância Clínica , Movimento (Física) , Reconhecimento Psicológico
17.
Exp Physiol ; 108(9): 1154-1171, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37409754

RESUMO

NEW FINDINGS: What is the central question of the study? Ageing is postulated to lead to underperfusion of human limb tissues during passive and exertional hyperthermia, but findings to date have been equivocal. Thus, does age have an independent adverse effect on local haemodynamics during passive single-leg hyperthermia, single-leg knee-extensor exercise and their combination? What is the main finding and its importance? Local hyperthermia increased leg blood flow over three-fold and had an additive effect during knee-extensor exercise with no absolute differences in leg perfusion between the healthy, exercise-trained elderly and the young groups. Our findings indicate that age per se does not compromise lower limb hyperaemia during local hyperthermia and/or small muscle mass exercise. ABSTRACT: Heat and exercise therapies are recommended to improve vascular health across the lifespan. However, the haemodynamic effects of hyperthermia, exercise and their combination are inconsistent in young and elderly people. Here we investigated the acute effects of local-limb hyperthermia and exercise on limb haemodynamics in nine healthy, trained elderly (69 ± 5 years) and 10 young (26 ± 7 years) adults, hypothesising that the combination of local hyperthermia and exercise interact to increase leg perfusion, albeit to a lesser extent in the elderly. Participants underwent 90 min of single whole-leg heating, with the contralateral leg remaining as control, followed by 10 min of low-intensity incremental single-leg knee-extensor exercise with both the heated and control legs. Temperature profiles and leg haemodynamics at the femoral and popliteal arteries were measured. In both groups, heating increased whole-leg skin temperature and blood flow by 9.5 ± 1.2°C and 0.7 ± 0.2 L min-1 (>3-fold), respectively (P < 0.0001). Blood flow in the heated leg remained 0.7 ± 0.6 and 1.0 ± 0.8 L min-1 higher during exercise at 6 and 12 W, respectively (P < 0.0001). However, there were no differences in limb haemodynamics between cohorts, other than the elderly group exhibiting a 16 ± 6% larger arterial diameter and a 51 ± 6% lower blood velocity following heating (P < 0.0001). In conclusion, local hyperthermia-induced limb hyperperfusion and/or small muscle mass exercise hyperaemia are preserved in trained older people despite evident age-related structural and functional alterations in their leg conduit arteries.


Assuntos
Hiperemia , Hipertermia Induzida , Humanos , Idoso , Extremidade Inferior , Perna (Membro)/irrigação sanguínea , Músculos , Fluxo Sanguíneo Regional/fisiologia , Músculo Esquelético/fisiologia
18.
Gastroenterol. hepatol. (Ed. impr.) ; 46(5): 350-359, May. 2023. ilus, tab, graf
Artigo em Espanhol | IBECS | ID: ibc-220004

RESUMO

Background and aims: A dysfunctional immune response is key to the pathogenesis of acute-on-chronic liver failure (ACLF). It has been suggested that treatment with granulocyte colony-stimulating factor (G-CSF) increases survival in patients with ACLF by improving immune cell dysfunction and promoting liver regeneration. The aim of the study is to evaluate the survival benefit associated with G-CSF administration compared with standard medical therapy (SMT) in ACLF. Methods: Systematic review and meta-analysis of randomized controlled trials. The primary outcome was survival at 60–90 days. We searched Ovid Medline, EMBASE, and Cochrane Central Register of Controlled Trials from inception to August 2021. Manual searches of reference lists in relevant articles and conference proceedings were also included. The revised Cochrane risk-of-bias tool was used for quality and risk of bias assessment. Two independent investigators extracted the data, and disagreements were solved by a third collaborator. Results: The initial search identified 142 studies. Four randomized controlled trials were selected for quantitative analysis including 310 patients (154 G-CSF and 156 SMT). Significant heterogeneity was observed (I2=74%, Chi2=11.57, p=0.009). G-CSF administration did not improve survival in patients with ACLF (random-effects model, risk ratio=0.64 [95% CI 0.39, 1.07]). However, when considering only the results from the studies performed in Asia, a significant decrease on mortality was observed (risk ratio=0.53 [95% CI 0.35, 0.81]). Severity scores (MELD and Child) and CD34+ peripheral cells mobilization did not significantly improve with G-CSF. Conclusion. In a systematic review and meta-analysis, G-CSF administration did not significantly improve overall survival compared to SMT in patients with ACLF...(AU)


Antecedentes y objetivos: La respuesta inmune disfuncional es clave en la patogénesis del fallo hepático agudo sobre crónico (ACLF). Se ha sugerido que la utilización de factor estimulante de colonias de granulocitos (G-CSF) aumenta la supervivencia de los pacientes con ACLF al mejorar la disfunción inmune y promover la regeneración hepática. El objetivo del estudio es evaluar el beneficio en supervivencia que proporciona la administración de G-CSF en comparación con el tratamiento médico estándar (SMT) en pacientes con ACLF. Métodos: Se llevó a cabo una revisión sistemática y meta-análisis de estudios aleatorizados y controlados. El objetivo principal fue analizar la supervivencia a los 60-90 días. Se realizó una búsqueda en Ovid Medline, EMBASE, y el registro central de estudios controlados de Cochrane desde su inicio hasta agosto 2021. También se realizaron búsquedas manuales en la bibliografía de artículos relevantes y presentaciones a congresos. Se utilizó la herramienta revisada de Cochrane para analizar la calidad y el riesgo de sesgos. Los datos fueron extraídos por dos investigadores independientes y las discrepancias fueron resueltas por un tercer investigador. Resultados: La búsqueda inicial identificó 142 estudios. De estos, 4 aleatorizados y controlados fueron elegidos para el análisis cuantitativo, incluyendo un total de 310 pacientes (154 G-CSF y 156 SMT). Se objetivó un alto grado de heterogeneidad entre los estudios (I2 = 74%, Chi 2 = 11.57, p = 0.009). La administración de G-CSF no aumentó la supervivencia en el grupo de pacientes con ACLF (modelo de efectos aleatorios, risk ratio = 0.64 [95% CI 0.39, 1.07]). Sin embargo, cuando se analizó el subgrupo de estudios realizados en Asia, sí se objetivó una disminución significativa de la mortalidad (risk ratio = 0.53 [95% CI 0.35, 0.81]). Las escalas de gravedad (MELD y Child) y la movilización de células CD34+ periféricas no mejoró significativamente tras la administración de G-CSF....(AU)


Assuntos
Humanos , Granulócitos , Fator Estimulador de Colônias de Granulócitos , Falência Hepática Aguda , Fibrose , Gastroenterologia , Gastroenteropatias
19.
Eur J Investig Health Psychol Educ ; 13(3): 595-612, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36975398

RESUMO

BACKGROUND: The passage through university is a complex experience that can heighten personal susceptibility to eating disorders. The objective of this research is to determine how gender, age, course, educational faculty, and body mass index (BMI) can influence the risk of eating disorders among university students. METHOD: A transversal and descriptive study is conducted with a sample of 516 Spanish students (57.2% female, 42.8% male; Mage = 21.7, SDage = 4.1) following 26 university degrees. The Inventory Eating Disorder-Reference criterion (EDI-3-RF) was administered to the students. Contingency tables were used between categorical variables with the chi-squared statistic, at a significance level of p < 0.05. The Student t-test was used for two independent samples and a one-way ANOVA test with the post hoc Bonferroni test for more than two groups. Pearson's correlation and a simple linear regression analysis were used to analyze the relationship between the variables in its quantitative version. RESULTS: It was found that the female students enrolled in the second year presented a greater obsession with thinness and body dissatisfaction (p = 0.029; d = 0.338); the male students practiced more physical exercise to control their weight (p = 0.003); and that students under the age of twenty (p < 0.010; d = 0.584) and students from both the Health (p = 0.0.13) and Law (p = 0.021) educational faculties showed greater bulimic behavior (d = 0.070). More females are underweight (z = 2.8), and more men are overweight (z = 2.4). Normal-weight students scored significantly higher in thinness obsession (p = 0.033). Overweight students scored significantly higher on thinness obsession (p < 0.001) and body dissatisfaction (p < 0.001). Obese students scored significantly higher on body dissatisfaction (p = 0.04). CONCLUSIONS: The data obtained in this study, reinforce the hypothesis that the female gender, at an age within the limits of early adolescence, in the first year of the degree courses, with specific university qualifications, and a high BMI constituted factors that could provoke an eating disorder. Consequently, it is necessary to implement preventive measures adapted to the circumstances of each university student.

20.
Membranes (Basel) ; 13(2)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36837690

RESUMO

Electromembrane processes for LiOH production from lithium brines obtained from solar evaporation ponds in production processes of the Salar de Atacama are considered. In order to analyze high concentrations' effect on ion exchange membranes, the use of concentrated LiCl aqueous solutions in a bipolar membrane electrodialysis process to produce LiOH solutions higher than 3.0% by mass is initially investigated. For this purpose, a mathematical model based on the Nernst-Planck equation is developed and validated, and a parametric study is simulated considering as input variables electrolyte concentrations, applied current density, stack design, process design and membrane characteristics. As a novelty, this mathematical model allows estimating LiOH production in a wide concentration range of LiCl, HCl and LiOH solutions and its effect on the process, providing data on final LiOH solution purity, current efficiency, specific electricity consumption and membrane performance. Among the main results, a concentration of 4.0% to 4.5% by LiOH mass is achieved, with a solution purity higher than 95% by mass and specific electrical energy consumption close to 4.0 kWh/kg. The work performed provides key information on process sensitivity to operating conditions and process design characteristics. These results serve as a guide in the application of this technology to lithium hydroxide production.

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