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1.
Methods Mol Biol ; 2852: 123-134, 2025.
Artículo en Inglés | MEDLINE | ID: mdl-39235740

RESUMEN

Properly using controllable atmospheric containers can facilitate investigations of the survival abilities and physiological states of key and emerging-foodborne pathogens under recreated applicable food processing environmental conditions. Notably, saturated salt solutions can efficiently control relative humidity in airtight containers. This chapter describes a practical experimental setup, with necessary prerequisites for exposing foodborne pathogens to simulated and relevant food processing environmental conditions. Subsequent analyses for studying cell physiology will also be suggested.


Asunto(s)
Manipulación de Alimentos , Microbiología de Alimentos , Manipulación de Alimentos/métodos , Enfermedades Transmitidas por los Alimentos/microbiología , Viabilidad Microbiana , Bacterias/crecimiento & desarrollo , Humanos
2.
Int J Cosmet Sci ; 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39282719

RESUMEN

OBJECTIVE: Basic therapy is an integral part of the treatment of chronic skin diseases. However, the formulation of skin products should be analysed with respect to the physical stability and tolerance by the patients before applying them to diseased skin. In particular, the suitability of the formulation for use on damaged skin should be taken into consideration so that no exacerbation of the condition is caused. METHODS: The following approach investigated two formulations with the emulsifier sorbitan monostearate and one with the addition of polyethylene glycol 100 stearyl ether. The characterization included rheology, macroscopic and microscopic cream analysis compared to marketed products for basic therapy. Pyranine staining of stratum corneum (SC) and trans-epidermal water loss (TEWL) measurements were performed with ex vivo porcine SC to asses skin barrier function. RESULTS: The rheological characterization showed a gel-like, viscoelastic behaviour of the formulations and a viscosity in the same order of magnitude as the marketed products. Staining with pyranine revealed that skin damage caused by sodium lauryl sulfate was compensated by treatment with the developed formulations. Following the same trend, TEWL results clearly showed decreasing values, which evidence improved skin barrier function. CONCLUSION: In conclusion, the developed sorbitan monostearate formulations can potentially improve deficient skin barrier function as a part of basic therapy of skin diseases and act as a superior alternative to market products comprising a minimum of well-chosen ingredients.


OBJECTIF: la thérapie de base fait partie intégrante du traitement des maladies chroniques de la peau. Cependant, la formulation des produits pour la peau doit être analysée en termes de stabilité physique et de tolérance par les patients avant de les appliquer sur la peau malade. En particulier, il convient de prendre en compte l'adéquation de la formulation à être utilisée sur une peau lésée afin d'éviter toute exacerbation de l'affection. MÉTHODES: l'approche suivante a étudié deux formulations avec l'émulsifiant monostéarate de sorbitane et une autre avec l'ajout d'éther de stéaryle de polyéthylène glycol 100. La caractérisation comprenait la rhéologie, l'analyse macroscopique et microscopique de la crème par rapport aux produits commercialisés pour la thérapie de base. Une coloration à la pyranine de la couche cornée et des mesures de la perte d'eau transépidermique ont été effectuées avec des couches cornées ex vivo de porc pour évaluer la fonction de barrière cutanée. RÉSULTATS: la caractérisation rhéologique a montré un comportement viscoélastique de type gel des formulations et une viscosité du même ordre de grandeur que les produits commercialisés. La coloration à la pyranine a révélé que les lésions cutanées causées par le laurylsulfate de sodium étaient compensées par le traitement avec les formulations développées. Suivant la même tendance, les résultats de la perte d'eau transépidermique ont clairement montré des valeurs en baisse, ce qui témoigne de l'amélioration de la fonction de barrière cutanée. CONCLUSION: en conclusion, les formulations de monostéarate de sorbitane développées peuvent potentiellement améliorer la fonction de barrière cutanée déficiente dans le cadre d'une thérapie de base des maladies de la peau et constituer une alternative supérieure.

3.
Int J Cosmet Sci ; 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39282751

RESUMEN

OBJECTIVE: Excessive and unpleasant odours that emanate from the skin can induce bromhidrosis and substantially impair a person's quality of life. Enzymatic pathways generating unpleasant odours are well detailed, and among them, the C-S lyase is one of the enzymes involved in the conversion of non-volatile precursors into thiol-type malodorous volatile molecules such as 3M3SH. This study aimed to investigate the variation of axillary odour intensity correlated with Staphylococcus (S.) hominis C-S lyase activity within a group of volunteers after a physical activity. METHODS: First, a group of 24 volunteers from the same ethnicity with standardized hygienic and alimentary practices participated in a supervised indoor cycling activity. Following this session, worn T-shirts were recovered to enable the olfactory evaluation of axillary odours by qualified experts. To go further, the microbiota from the axillary zone of each volunteer was sampled and the bacterial relative abundance was investigated by using 16S rRNA metasequencing. Then, S. hominis isolates were obtained by culturomics from these microbiota samples and the C-S lyase activity was measured by spectrofluorometry in protein crude extracts. RESULTS: The evaluation of the odour intensity revealed that within the panel, two groups were significantly distinct. A non-odorous group and a malodorous one with volunteers having unpleasant odours. The 16S rRNA metasequencing reveals differences in bacterial communities between the two groups with a significant increase in the relative abundance of S. hominis in the malodorous group compared with the non-odorous one. The C-S lyase activities measured on S. hominis sampled on volunteers from the two groups demonstrate that for an equivalent quantity of protein, this enzymatic activity is significantly higher for the samples originating from the malodorous group. CONCLUSION: Hence, this study demonstrates that beyond the increase of S. hominis relative abundance, the C-S lyase enzymatic activity of this bacteria is also higher in volunteers with unpleasant axillary odours.


OBJECTIF: Les odeurs excessives et désagréables qui émanent de la peau peuvent induire une bromhidrose et altérer considérablement la qualité de vie d'une personne. Les voies enzymatiques générant des odeurs désagréables sont bien détaillées, et parmi elles, la C­S lyase est l'une des enzymes impliquées dans la conversion de précurseurs non volatils en molécules volatiles malodorantes de type thiols, telles que le 3M3SH. Cette étude avait pour objectif d'investiguer la variation de l'intensité de l'odeur axillaire corrélée à l'activité de la C­S lyase de Staphylococcus (S.) hominis d'un groupe de volontaires après la pratique d'une activité sportive. MÉTHODES: Un groupe de 24 volontaires de la même ethnie ayant des pratiques hygiéniques et alimentaires standardisées ont participé à une séance calibrée de vélo d'intérieur. Après cette activité, les t­shirts portés ont été récupérés pour permettre l'évaluation olfactive des odeurs axillaires par des experts qualifiés. Pour aller plus loin, le microbiote de la zone axillaire de chaque volontaire a été prélevé et l'abondance relative des bactéries a été étudiée par métaséquençage de l'ARNr 16S. Ensuite, des isolats de S. hominis ont été obtenus par culturomique à partir de ces échantillons de microbiote et l'activité de la C­S lyase a été mesurée par spectrofluorométrie dans des extraits protéiques totaux. RÉSULTATS: L'évaluation de l'intensité des odeurs a révélé qu'au sein du panel, deux groupes se distinguaient de manière significative. Un groupe non­odorant et un groupe malodorant avec des volontaires ayant des odeurs axillaires désagréables. Le métaséquençage de l'ARNr 16S révèle des différences dans les communautés bactériennes entre les deux groupes avec une augmentation significative de l'abondance relative de S. hominis dans le groupe malodorant par rapport au groupe non­odorant. L'activité enzymatique de la C­S lyase mesurée à partir d'isolats de S. hominis prélevés sur des volontaires des deux groupes démontrent que, pour une quantité équivalente de protéines, cette activité enzymatique est significativement plus élevée pour les échantillons provenant du groupe malodorant. CONCLUSION: Cette étude démontre qu'au­delà de l'augmentation de l'abondance relative de S. hominis, l'activité de la C­S lyase de cette bactérie est également plus élevée chez les volontaires présentant des odeurs axillaires désagréables.

4.
Lung ; 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39269458

RESUMEN

BACKGROUND: Diabetes is a risk factor for the development of vascular disease, chronic kidney disease, retinopathy, and neuropathy. Diabetes is a co-morbid condition commonly present in patients with respiratory disorders but the extent to which it influences ventilatory capacity, gas exchange, and functional capacity is not well known. Research question Does the presence of diabetes contribute to impairment in spirometry, gas transfer, and exercise capacity? METHODS: Retrospective analysis of all subjects who performed incremental cardio-pulmonary exercise testing (CPET) between 1988 and 2012 at McMaster University Medical Centre. The impact of diabetes on physiological outcomes and maximum power output (MPO) was assessed using stepwise multiple additive linear regression models including age, height, weight, sex, muscle strength, and previous myocardial infarct as co-variates, and was also stratified based on BMI categories. RESULTS: 40,776 subjects were included in the analysis; 1938 (5%, 66% male) had diabetes. Diabetics were older (59 vs. 53 years), heavier (88.3 vs.78.0 kg), and had a higher BMI (31 vs. 27 kg/m2). The presence of diabetes was independently associated with a reduction in FEV1 (- 130 ml), FVC (- 220 ml), DLCO (- 1.52 ml/min/mmHg), and VA (- 340ml) but not KCO. Patients with diabetes achieved a lower % predicted MPO[diabetic subjects 70% predicted (670 kpm/min ± 95% CI 284) vs. 80% in non-diabetics (786 kpm/min ± 342), p < 0.001]. With the exception of KCO, these differences persisted across BMI categories and after adjusting for MI. CONCLUSION: The presence of diabetes is independently associated with weaker muscles, lower ventilatory and gas transfer capacity and translates to a lower exercise capacity. These differences are independent of age, height, weight, sex, and previous MI.

5.
iScience ; 27(9): 110661, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39262774

RESUMEN

Contact with dense collagen I (Col1) can induce collective invasion of triple negative breast cancer (TNBC) cells and transcriptional signatures linked to poor patient prognosis. However, this response is heterogeneous and not well understood. Using phenotype-guided sequencing analysis of invasive vs. noninvasive subpopulations, we show that these two phenotypes represent opposite sides of the iron response protein 1 (IRP1)-mediated response to cytoplasmic labile iron pool (cLIP) levels. Invasive cells upregulate iron uptake and utilization machinery characteristic of a low cLIP response, which includes contractility regulating genes that drive migration. Non-invasive cells upregulate iron sequestration machinery characteristic of a high cLIP response, which is accompanied by upregulation of actin sequestration genes. These divergent IRP1 responses result from Col1-induced transient expression of heme oxygenase I (HO-1), which cleaves heme and releases iron. These findings lend insight into the emerging theory that heme and iron fluxes regulate TNBC aggressiveness.

6.
Sensors (Basel) ; 24(17)2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39275598

RESUMEN

We aimed to conduct a biophysical comparison of angular (Biorower) and linear (Concept2) rowing ergometers across a wide spectrum of exercise intensities. Sixteen (eleven male) skilled rowers, aged 29.8 ± 8.6 and 23.6 ± 1.5 years, with international competitive experience, performed 7 × 3 min bouts with 30 W increments and 60 s intervals, plus 1 min of all-out rowing on both machines with 48 h in between. The ventilatory and kinematical variables were measured breath-by-breath using a telemetric portable gas analyzer and determined using a full-body markerless system, respectively. Similar values of oxygen uptake were observed between ergometers across all intensity domains (e.g., 60.36 ± 8.40 vs. 58.14 ± 7.55 mL/min/kg for the Biorower and Concept2 at severe intensity). The rowing rate was higher on the Biorower vs. Concept2 at heavy and severe intensities (27.88 ± 3.22 vs. 25.69 ± 1.99 and 30.63 ± 3.18 vs. 28.94 ± 2.29). Other differences in kinematics were observed across all intensity domains, particularly in the thorax angle at the finish (e.g., 19.44 ± 4.49 vs. 27.51 ± 7.59° for the Biorower compared to Concep2 at heavy intensity), likely due to closer alignment of the Biorower with an on-water rowing technique. The overall perceived effort was lower on the Biorower when compared to the Concept2 (14.38 ± 1.76 vs. 15.88 ± 1.88). Rowers presented similar cardiorespiratory function on both rowing ergometers, while important biomechanical differences were observed, possibly due to the Biorower's closer alignment with an on-water rowing technique.


Asunto(s)
Ergometría , Ejercicio Físico , Consumo de Oxígeno , Deportes Acuáticos , Humanos , Masculino , Adulto , Ergometría/métodos , Ergometría/instrumentación , Deportes Acuáticos/fisiología , Ejercicio Físico/fisiología , Adulto Joven , Femenino , Consumo de Oxígeno/fisiología , Fenómenos Biomecánicos/fisiología
7.
iScience ; 27(9): 110741, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39280604

RESUMEN

Osteoarthritis (OA) is a progressive degenerative joint disease, and the underlying molecular mechanisms of OA remain poorly understood. This study aimed to elucidate the relationship between mitochondrial autophagy and OA by identifying key regulatory genes and their biological functions. Utilizing bioinformatics analyses of RNA expression profiles from the GSE55235 dataset, we identified 2,136 differentially expressed genes, leading to the discovery of hub genes associated with mitochondrial autophagy and OA. Gene set enrichment analysis (GSEA) revealed their involvement in critical pathways, highlighting their potential roles in OA pathogenesis. Furthermore, our study explored the immunological landscape of OA, identifying distinct immune cell infiltration patterns that contribute to the disease's inflammatory profile. We also evaluated the therapeutic potential of drugs targeting these hub genes, suggesting potential approaches for OA treatment. Collectively, this study advances our knowledge of mitochondrial autophagy in OA and proposes promising biomarkers and therapeutic targets.

8.
iScience ; 27(9): 110767, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39280605

RESUMEN

Intra-islet crosstalk has become a focus area to fully understand the regulation of insulin secretion and impaired ß-cell function in type 2 diabetes (T2D). Here, we put forward evidence for insulin-like growth factor binding protein 7 (IGFBP7) as a potential protein involved in autocrine and paracrine ß-cell regulation. We showed presence of IGFBP7 in granules of both human α- and ß-cells and measured elevated gene expression as well as IGFBP7 protein in T2D. Insulin secretion was reduced in human islets, and the human ß-cell line EndoC-ßH1, after 72-h incubation with IGFBP7. Mechanistically reduced insulin secretion by IGFBP7 is attributed to reduced p21-activated kinase 1 (PAK1) protein, and decreased oxygen consumption and ATP-production. Knockdown of IGFBP7 in EndoC-ßH1 cells verified reduced IGFBP7 levels in the medium, as well as improved insulin secretion. Finally, IGFBP7 knockdown in islets from T2D donors improved insulin secretion, making IGFBP7 a potential drug target in diabetes.

9.
Toxicol Rep ; 13: 101718, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39280990

RESUMEN

Aluminum phosphide (AlP) poisoning is a life-threatening emergency prevalent in the Middle East region including Egypt. Early prediction of prognosis is critical for initiating the utmost intensive interventions. Though many scoring systems were studied for predicting the prognosis of AlP poisoning, these scores received wide criticism. Complexity and reliability were the main concerns. Therefore, this retrospective cross-sectional study aimed to evaluate the performance of the recently introduced PGI score as a predictor of case fatality, the need for mechanical ventilation and vasopressor therapy in acute AlP poisoning. Moreover, it compares the performance of PGI with the known poison severity score (PSS), and the simplified acute physiology score (SAPS) II. Among 144 exposed patients, we reported a mortality rate of 61.1%. Non-survivors exhibited significantly higher PGI, PSS, and SAPS II than survivors. Though the PGI, PSS, and SAPS II proved their significance as predictors of mortality and, the need for MV and vasopressors, the PGI score showed a significantly higher area under the curve (AUC) as a predictor of MV (AUC = 0.848) compared to PSS (AUC = 0.731) and SAPS II (AUC = 0.749). Additively, PGI of 2 or more was a significant predictor of mortality (AUC = 0.831, sensitivity = 65.9%, and specificity = 89.3 %) and MV (p < 0.001), while PGI of 1 or more was another predictor of vasopressor need (AUC = 0.881, sensitivity = 89.0% and specificity = 79.4%). Given the PGI score's high AUCs across all outcomes, coupled with its balanced sensitivity and specificity, the PGI score could be a simple, and robust tool replacing the PSS and SAPS II for predicting mortality, clinical decision-making including the need for MV and vasopressor therapy in acute AlP exposure. Adopting the PGI score seems substantially useful in managing acute AlP poisoning, notably in resource-restricted countries.

10.
iScience ; 27(9): 110785, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39286503

RESUMEN

Supernumerary teeth are common developmental anomalies of dentition. However, the factors and mechanisms driving their formation remain largely unknown. Here, we report that conditional knockout of Fst, encoding an antagonist for the transforming growth factor ß (TGF-ß) signaling pathway, in both oral epithelium and mesenchyme of mice (Fst CKO ) led to supernumerary upper incisor teeth, arising from the lingual dental epithelium of the native teeth and preceded by an enlarged and split lingual cervical loop. Fst-deficiency greatly activated TGF-ß signaling in developing maxillary incisor teeth, associated with increased epithelium cell proliferation. Moreover, Fst CKO teeth exhibited increased expression of Tbx1, Sp6, and Sox2, which were identified as direct targets of TGF-ß/SMAD2 signaling. Finally, we show that upregulation of Tbx1 in response to Fst-deficiency was largely responsible for the formation of extra teeth in Fst CKO mice. Taken together, our investigation indicates a novel role for Fst in controlling murine tooth number by restricting TGF-ß signaling.

11.
Kidney Int Rep ; 9(9): 2619-2626, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39291202

RESUMEN

Introduction: Recent technological advancements allowed the development of engaging technological tools. Using ASN funding from the ASN, we developed a 3D Virtual Reality (VR) physiology course entitled DiAL-Neph (Diuretic Action and eLectrolyte transport in the Nephron). We hereby present its evaluation. Methods: The study consisted of 2 parts: evaluation of knowledge gain, and qualitative evaluation of platform reception. Internal medicine PGY1 residents were randomly assigned into 2 groups: a VR group and a conventional group. Knowledge acquisition was assessed with a post-test administered at the end of the course and repeated within 6 to 12 weeks. Independent t-tests were used to compare the number of correct answers between the groups. A survey and focus groups composed of medicine residents evaluated the platform. Sessions were recorded and transcribed verbatim. Data was analyzed through the content analysis approach by two independent reviewers. Results: Of 117 PGY1 resident participants, 64 were randomized to the VR group and 53 were randomized to the traditional group. Initial test results showed higher scores among VR compared to the traditional group (76.5% correct vs. 68.8%). Seventy-eight PGY1s participated in the follow up testing (46 VR group vs. 32 traditional group) and results showed no significant difference in test results. Greater than 90% of the residents rated the platform positively and 77% preferred it as a teaching method. Conclusion: The DiAL-Neph VR platform appeared to improve short-term learning but not long-term retention. Further studies are needed to investigate the impact of such teaching platforms on overall interest in nephrology.

12.
J Cosmet Dermatol ; 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39291708

RESUMEN

OBJECTIVE: Environmental factors are important in the generation or aggravation of sensitive skin syndrome (SSS). Creams can be useful for patients with SSS, particularly when triggering factors cannot be avoided. Several clinical studies have investigated the safety and efficacy of specific creams in patients with SSS, but the majority were assessed with a single type of triggering factor and were non-comparative. Therefore, this study's aim was to investigate, the benefit of a specific dermo-cosmetic product in response to physical and chemical factors in subjects with SSS. METHODS: Three clinical studies were performed on subjects presenting SSS. The physical impact was assessed in a stripping test, and in a randomized intra-individual study with a newly developed heat-cold stress model. To assess chemical factors, a capsaicin test on the nasolabial fold was performed. RESULTS: The product significantly reduced the increase in skin microcirculation caused by stripping after 30 min versus. The untreated condition (45.8% vs. 62.0%; p < 0.01). Immediately and at D28, the product induced a significant increase in skin hydration even after a heat-cold stress, while the overall score of unpleasant symptoms significantly decreased compared with the control (8.1 vs. 10.7 and 3.7 vs. 8.0, respectively; p < 0.01). Regarding chemical factors, a significant difference in the sensation intensity (p < 0.001) was observed after capsaicin stress, also in terms of the sensation duration due to the product application versus the control (192 s vs. 403 s; p < 0.001). CONCLUSION: These studies show that topical application of a dermo-cosmetic product can prevent unpleasant symptoms and improve the skin state in SSS exposed to physical and chemical triggering factors.

13.
Adv Physiol Educ ; 48(4): 708-711, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39291936

RESUMEN

Formative assessment is a valuable tool in medical education as it allows students to reflect on their own learning and make necessary corrections. The use of innovative techniques in formative assessment can make it more engaging and effective for students, particularly utilizing electronic tools. A word cloud is a visual representation of data that is created using text inputs from a group of individuals. The resulting image shows the most frequently used words in a larger font, allowing quick understanding of the common themes and concepts in the group's responses. Mentimeter is an online platform for interactive presentations where students can provide their responses to a question, which can then be visualized as a word cloud. The study aims to explore the benefits and drawbacks of using word cloud formation as a formative assessment technique in the classroom, utilizing the online platform Mentimeter.NEW & NOTEWORTHY The current study was conducted to present a novel formative assessment classroom technique using Mentimeter. The benefit of this novel technique is that it is easy to implement, quick, anonymous, and strengthens student's conceptual learning. It also gives the teacher an opportunity to give feedback and stress commonly committed mistakes.


Asunto(s)
Evaluación Educacional , Fisiología , Estudiantes de Medicina , Humanos , Fisiología/educación , Evaluación Educacional/métodos , Educación de Pregrado en Medicina/métodos , Nube Computacional
14.
Adv Physiol Educ ; 48(4): 690-697, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39291935

RESUMEN

The teaching of physiology plays a crucial role in the education of health care professionals. However, traditional approaches to physiology classes in undergraduate health courses in Brazil often result in passive student participation. Research has shown that active methodologies are more effective in the learning process. In this study, we introduce the game "Who Am I?-Cellular Signal Transduction Edition" as an educational tool. This game follows a popular format with well-known rules and aims to enhance understanding of basic concepts related to hormones, cell signaling, and the functioning of the endocrine system. Our findings demonstrate that the game improves student knowledge and fosters enthusiasm and active engagement among participants. Additionally, student feedback has indicated a high level of appreciation for the game. By incorporating active learning strategies and a gamified approach, "Who Am I?-Cellular Signal Transduction Edition" provides a practical and enjoyable way of teaching physiology. This innovative educational tool has the potential to revolutionize physiology instruction. Demonstrating significant improvement in students' understanding, the game underscores its efficacy in enhancing knowledge acquisition and comprehension of cellular signaling and endocrine physiology topics.NEW & NOTEWORTHY We developed "Who Am I?-Cellular Signal Transduction Edition" to assist students in comprehending concepts of cellular signal transduction. This simple and cost-effective tool is perfect for educational settings with limited resources, and it encourages active learning for both small and large groups. Pre- and posttests have shown that it effectively enhances knowledge of hormonal actions and cellular signaling. Positive feedback from students emphasizes its value in reinforcing understanding and improving classroom engagement, making it a promising educational tool.


Asunto(s)
Fisiología , Aprendizaje Basado en Problemas , Humanos , Aprendizaje Basado en Problemas/métodos , Fisiología/educación , Masculino , Femenino , Transducción de Señal , Brasil , Adulto Joven , Educación de Pregrado en Medicina/métodos , Evaluación Educacional/métodos
15.
Geroscience ; 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39287879

RESUMEN

Assessing inter-muscular coordination in older adults is crucial, as it directly impacts an individual's ability for independent functioning, injury prevention, and active engagement in daily activities. However, the precise mechanisms by which distinct muscle fiber types synchronize their activity across muscles to generate coordinated movements in older adults remain unknown. Our objective is to investigate how distinct muscle groups dynamically synchronize with each other in young and older adults during exercise. Thirty-five young adults and nine older adults performed one bodyweight squat set until exhaustion. Simultaneous surface electromyography (sEMG) recordings were taken from the left and right vastus lateralis, and left and right erector spinae. To quantify inter-muscular coordination, we first obtained ten time series of sEMG band power for each muscle, representing the dynamics of different muscle fiber types. Next, we calculated the bivariate equal-time Pearson's cross-correlation for each pair of sEMG band power time series across all leg and back muscles. The main results show (i) an overall reduction in the degree of inter-muscular coordination, and (ii) increased stratification of the inter-muscular network in older adults compared to young adults. These findings suggest that as individuals age, the global inter-muscular network becomes less flexible and adaptable, hindering its ability to reorganize effectively in response to fatigue or other stimuli. This network approach opens new avenues for developing novel network-based markers to characterize multilevel inter-muscular interactions, which can help target functional deficits and potentially reduce the risk of falls and neuro-muscular injuries in older adults.

16.
J Clin Med ; 13(17)2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39274510

RESUMEN

This review examines the relationship between the physiological demands of diving and premature ventricular complexes (PVCs) in divers. In the general population, some individuals have a greater tendency to experience PVCs, often without awareness or a clear understanding of the triggering factors. With the increasing availability and popularity of both scuba and apnoea diving, more people, including those with a predisposition to PVCs, are engaging in these activities. The underwater environment, with its unique stressors, may increase the risk of arrhythmogenic events, particularly PVCs. Here, we review the prevalence, pathophysiology, and aggravating factors of PVCs in divers, emphasising the need for a comprehensive cardiovascular assessment. Evidence suggests a higher prevalence of PVCs in divers compared with the general population, influenced by factors such as age, dive depth, gas bubbles, cold water immersion, pre-existing cardiovascular diseases, and lifestyle factors. The change in environment during diving could potentially trigger an increased frequency of PVCs, especially in individuals with a pre-existing tendency. We discuss diagnostic strategies, management approaches, and preventive measures for divers with PVCs, noting that although guidelines for athletes can be adapted, individual assessment is crucial. Significant knowledge gaps are identified, highlighting the need for future research to develop evidence-based guidelines and understand the long-term significance of PVCs in divers. This work aims to evaluate potential contributing factors to PVCs in divers and identify individuals who may be at higher risk of experiencing major adverse cardiovascular events (MACEs). This work aims to improve diver safety by promoting collaboration between cardiologists and diving medicine specialists and by identifying key areas for future investigation in this field. This work aims to improve the safety and well-being of divers by understanding the cardiovascular challenges they face, including pressure changes, cold water immersion, and hypoxia. We seek to elucidate the relationship between these challenges and the occurrence of PVCs. By synthesising current evidence, identifying knowledge gaps, and proposing preliminary recommendations, we aim to encourage collaboration between cardiologists and diving medicine specialists to optimise the screening, management, and risk stratification of PVCs in the diving population.

18.
Cell Rep ; 43(9): 114718, 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39277859

RESUMEN

Large-scale analysis of single-cell gene expression has revealed transcriptomically defined cell subclasses present throughout the primate neocortex with gene expression profiles that differ depending upon neocortical region. Here, we test whether the interareal differences in gene expression translate to regional specializations in the physiology and morphology of infragranular glutamatergic neurons by performing Patch-seq experiments in brain slices from the temporal cortex (TCx) and motor cortex (MCx) of the macaque. We confirm that transcriptomically defined extratelencephalically projecting neurons of layer 5 (L5 ET neurons) include retrogradely labeled corticospinal neurons in the MCx and find multiple physiological properties and ion channel genes that distinguish L5 ET from non-ET neurons in both areas. Additionally, while infragranular ET and non-ET neurons retain distinct neuronal properties across multiple regions, there are regional morpho-electric and gene expression specializations in the L5 ET subclass, providing mechanistic insights into the specialized functional architecture of the primate neocortex.

19.
Artículo en Inglés | MEDLINE | ID: mdl-39278733

RESUMEN

Coronary circulation plays an essential role in delivering oxygen and metabolic substrates to satisfy the considerable energy demand of the heart. This article reviews the history that led to the current understanding of coronary physiology, beginning with William Harvey's revolutionary discovery of systemic blood circulation in the 17th century, and extending through the 20th century when the major mechanisms regulating coronary blood flow (CBF) were elucidated: extravascular compressive forces, metabolic control, pressure-flow autoregulation, and neural pathways. Pivotal research studies providing evidence for each of these mechanisms are described, along with their clinical correlates. The authors describe the major role played by researchers in the 19th century, who formulated basic principles of hemodynamics, such as Poiseuille's law, which provided the conceptual foundation for experimental studies of CBF regulation. Targeted research studies in coronary physiology began in earnest around the turn of the 20th century. Despite reliance on crude experimental techniques, the pioneers in coronary physiology made groundbreaking discoveries upon which our current knowledge is predicated. Further advances in coronary physiology were facilitated by technological developments, including methods to measure phasic CBF and its regional distribution, and by biochemical discoveries, including endothelial vasoactive molecules and adrenergic receptor subtypes. The authors recognize the invaluable contribution made by basic scientists toward the understanding of CBF regulation, and the enormous impact that this fundamental information has had on improving clinical diagnosis, decision-making, and patient care.

20.
J Physiol Sci ; 74(1): 42, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39285320

RESUMEN

Transient receptor potential (TRP) ion channels serve as sensors for variations in ambient temperature, modulating both thermoregulation and temperature responsive cellular processes. Among these, the vanilloid TRP subfamily (TRPV) comprises six members and at least four of these members (TRPV1-TRPV4) have been associated with thermal sensation. TRPV2 has been described as a sensor for noxious heat, but subsequent studies have unveiled a more complex role for TRPV2 beyond temperature perception. This comprehensive review aims to elucidate the intricate thermosensitivity of TRPV2 by synthesizing current knowledge on its biophysical properties, expression pattern and known physiological functions associated with thermosensation.


Asunto(s)
Canales Catiónicos TRPV , Sensación Térmica , Canales Catiónicos TRPV/metabolismo , Humanos , Animales , Sensación Térmica/fisiología , Regulación de la Temperatura Corporal/fisiología
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