Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 97.481
Filtrar
1.
Isotopes Environ Health Stud ; : 1-15, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949394

RESUMO

Understanding the critical thresholds of dissolved oxygen (O2) that trigger adaptive physiological responses in aquatic organisms is long hampered by a lack of robust, non-lethal or non-invasive methodologies. The isotope fractionation of triple O2 isotopes (18O/17O/16O) during respiration is linked to the amount of oxygen utilised, offering a potential avenue for new insights. Our experimental research involved measuring the oxygen isotope fractionation of dissolved O2 in closed-system aquatic respirometry experiments with wild sticklebacks (Gasterosteus aculeatus). These fish were either naturally adapted or experimentally acclimated to hypoxic and normoxic conditions. The aim was to observe their oxygen usage and isotope fractionation in response to increasingly severe hypoxia. Initial observations revealed a progressive 18O enrichment from the preferential uptake of 16O to a dissolved oxygen threshold of 3-5 mg O2 L-1, followed by an apparent reversal in oxygen isotope fractionation, which is mixing of 16O and 17O with the remaining O2 pool across all populations and indicative of a systematic change in oxygen metabolism among the fish. Unexpectedly, sticklebacks adapted to hypoxia but acclimated to normoxia exhibited stronger oxygen isotope fractionation compared to those adapted to normoxia and acclimated to hypoxia, contradicting the hypothesis that hypoxia adaptation would lead to reduced isotope discrimination due to more efficient oxygen uptake. These preliminary experimental results highlight the novel potential of using dissolved O2 isotopes as a non-invasive, non-lethal method to quantitatively assess metabolic thresholds in aquatic organisms. This approach could significantly improve our understanding of the critical oxygen responses and adaptation mechanisms in fish and other aquatic organisms across different oxygen environments, marking a significant step forward in aquatic ecological and physiological research.

2.
ChemSusChem ; : e202400582, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953395

RESUMO

In the chemical industry, formaldehyde is an important bulk chemical. The traditional synthesis of formaldehyde involves an energy intensive oxidation of methanol over a metal oxide catalyst. The selective electrochemical oxidation of methanol is challenging. Herein, we report a catalytic system with an immobilized TEMPO electrode that selectively oxidizes methanol to formaldehyde with high turnover numbers. Upon the addition of various organic and inorganic bases, the activity of the catalyst could be tuned. The highest Faradaic efficiency that was achieved was 97.5 %, the highest turnover number was 17100. Additionally, we found that the rate determining step changed from the step in which the carbonyl specie is created from the methanol-TEMPO adduct to the oxidative regeneration of the TEMPO+ species. Finally, we showed that the system could be applied to the oxidation of other aliphatic alcohols.

3.
Biol Lett ; 20(7): 20240217, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38955225

RESUMO

Whether avian migrants can adapt to their changing world depends on the relative importance of genetic and environmental variation for the timing and direction of migration. In the classic series of field experiments on avian migration, A. C. Perdeck discovered that translocated juveniles failed to reach goal areas, whereas translocated adults performed 'true-goal navigation'. His translocations of > 14 000 common starlings (Sturnus vulgaris) suggested that genetic mechanisms guide juveniles into a population-specific direction, i.e. 'vector navigation'. However, alternative explanations involving social learning after release in juveniles could not be excluded. By adding historical data from translocation sites, data that was unavailable in Perdeck's days, and by integrated analyses including the original data, we could not explain juvenile migrations from possible social information upon release. Despite their highly social behaviour, our findings are consistent with the idea that juvenile starlings follow inherited information and independently reach their winter quarters. Similar to more solitarily migrating songbirds, starlings would require genetic change to adjust the migration route in response to global change.


Assuntos
Migração Animal , Comportamento Social , Estorninhos , Animais , Estorninhos/fisiologia , Estorninhos/genética , Estações do Ano
4.
Zhonghua Bing Li Xue Za Zhi ; 53(7): 697-701, 2024 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-38955701

RESUMO

Objective: To investigate the clinicopathological and genetic features of confined placental mosaicism (CPM) and its effect on fetal intrauterine growth. Methods: Fourteen CPM cases of Haidian Maternal and Children Health Hospital were collected from May 2018 to March 2022. Clinicopathological examination on placental specimens and molecular genetic analysis were performed. Results: The age of the parturient women ranged from 27 to 34 years, with an average age of (30.0±3.54) years. The gestational weeks ranged from 35+1 to 41+2 weeks. There were 4 premature births and 10 term births, among which 6 were female and 8 were male fetuses. Nine cases (9/14) had adverse pregnancy outcomes, including 7 cases of fetal growth restriction. The weight of CPM placenta decreased, with 6 cases below the 10th percentile of weight standards and 5 cases between the 10th and 25th percentile. All 14 CPM placental specimens showed morphological changes of perfusion dysfunction to varying degrees, with mainly placental-maternal vascular malperfusion followed by placental-fetal vascular malperfusion. The mosaic chromosomes in different CPM cases varied, with 16-trisomy/monosomy mosaicism being the most common followed by 7-trisomy and 21-trisomy/monosomy mosaicism. The mosaic proportion was unequal in different parts of the same CPM placenta, with the mosaic proportion of umbilical cord, fetal membranes, fetal surface, maternal surface, and edge ranging from 1% to 70%. Conclusions: The mosaic chromosomes in different CPM cases vary, and the mosaic proportion is unequal in different parts of the same CPM placenta. The pathological morphology is mainly manifested as perfusion dysfunction, which can lead to adverse pregnancy outcomes such as fetal growth restriction and preterm birth.


Assuntos
Retardo do Crescimento Fetal , Mosaicismo , Placenta , Humanos , Gravidez , Feminino , Adulto , Placenta/patologia , Retardo do Crescimento Fetal/genética , Retardo do Crescimento Fetal/patologia , Resultado da Gravidez , Masculino , Doenças Placentárias/patologia , Doenças Placentárias/genética , Trissomia/genética , Recém-Nascido , Idade Gestacional
5.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(6): 875-882, 2024 Jun 06.
Artigo em Chinês | MEDLINE | ID: mdl-38955736

RESUMO

Objective: To explore the relationship between serum 1, 5-dehydratoglucitol (1, 5-AG) level and insulin resistance, microvascular complications in patients with type 2 diabetes mellitus (T2DM). Methods: The clinical data of 836 patients with T2DM admitted to the Changsha Central Hospital Affiliated to University of South China from May to December 2023 were retrospectively and cross-sectionally analyzed. Serum 1, 5-AG levels were detected by pyranose oxidase method. According to the microvascular complications (diabetic peripheral neuropathy, diabetic nephropathy, diabetic retinopathy), the patients were divided into simple group (no microvascular complications, n=490), complication group 1 (1 microvascular complications, n=217), and complication group 2 (2 or more microvascular complications, n=129). The relationship between serum 1, 5-AG level and the related indicators of insulin resistance in T2DM patients were explored by Spearman correlation analysis, and the influencing factors of microvascular complications in T2DM patients were explored by multiple ordered logistic regression analysis. Results: The levels of FBG(fasting blood glucose) [(7.37±0.56) mmol/L], FINS(fasting insulin) [(11.34±1.86) mU/L] and HOMA-IR(homeostatic model assessment of insulin resistance) (0.96±0.31) in simple group were lower than those in complication group 1 [(8.37±1.02) mmol/L, (16.26±2.32) mU/L, (1.32±0.41)], complication group 2 [(10.25±2.13) mmol/L, (18.53±2.67) mU/L, (1.54±0.44)], and FBG, FINS and HOMA-IR in complication group 1 were lower than those in complication group 2, and the differences were statistically significant (F=537.470, 791.690, 136.340, P<0.001). Serum 1, 5-AG level in simple group [77.16 (16.30, 128.07) µg/ml] was higher than that in complication group 1 [51.05 (14.67, 63.18) µg/ml] and complication group 2 [30.42 (12.53, 47.26) µg/ml], and the serum level of 1, 5-AG in complication group 1 was higher than that in complication group 2, and the difference was statistically significant (H=210.020, P<0.001). The results of Spearman correlation analysis showed that serum 1, 5-AG level was negatively correlated with FBG, FINS and HOMA-IR in T2DM patients (r=-0.431, -0.372, -0.546, P<0.001). The results of multiple ordered logistic regression analysis showed that Longer duration of diabetes (OR=2.261, 95%CI: 1.564-3.269), increased HbA1c (OR=2.040, 95%CI: 1.456-2.858), and increased HOMA-IR (OR=2.158, 95%CI: 1.484-3.137) and decreased 1, 5-AG (OR=2.512, 95%CI: 1.691-3.732) were independent risk factors for microvascular complications in T2DM patients (P<0.05). The results of ROC curve analysis showed that the area under the curve of serum 1, 5-AG in the identification of one microvascular complication was 0.763 (95%CI: 0.731-0.795), and the area under the curve of serum 1, 5-AG in the identification of two or more microvascular complications was 0.730 (95%CI: 0.692-0.767). Conclusion: Serum 1, 5-AG level is negatively correlated with insulin resistance in T2DM patients. Low serum 1, 5-AG level may be an independent risk factor for microvascular complications in T2DM patients.


Assuntos
Desoxiglucose , Diabetes Mellitus Tipo 2 , Resistência à Insulina , Humanos , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Estudos Transversais , Estudos Retrospectivos , Desoxiglucose/sangue , Desoxiglucose/análogos & derivados , Glicemia , Masculino , Feminino , Insulina/sangue , Pessoa de Meia-Idade , Angiopatias Diabéticas/sangue
6.
J Psychosom Res ; 184: 111833, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38959575

RESUMO

OBJECTIVE: Surviving physical trauma can have a large impact on one's daily life. Patients are at increased risk for poor physical health, psychological complaints, and problems in role functioning - which is often experienced simultaneously. The present study explores the interconnectedness of physical, psychological, and role functioning during the first two years post-injury, both cross-sectionally and longitudinally from a network perspective. METHODS: 3785 trauma patients (Mage = 64.2 years, SDage = 18.9 years, 50.5% female) completed questionnaires on physical, psychological, and role functioning across six measurement occasions during the first two years post-injury. The Injury Severity Score (ISS) was retrieved from the local trauma registry. Mixed graphical network models and cross-lagged network models were estimated to examine which items of recovery played a central role and were mostly related to other items in cross-sectional and longitudinal networks respectively. RESULTS: The cross-sectional networks showed especially strong interconnections between impairments of physical and role functioning and also within post-traumatic stress symptoms. The longitudinal networks extended these results by showing that pain, impaired mobility, limitations in self-care, anxiety/depressive symptoms, and several post-traumatic stress symptoms were strong predictors for impairments in functioning at later stages of recovery. CONCLUSION: Our findings showed that impairments in physical, psychological, and role functioning experienced by trauma patients are largely intertwined across the two years following injury. Monitoring physical impairments and psychological complaints early in recovery might help to more promptly provide the best fitting aftercare for trauma patients, which can improve recovery on the long-term.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38957043

RESUMO

BACKGROUND: Despite reported physical and functional improvements with aerobic and sprint interval training (SIT) protocols in individuals with intellectual disability (ID), it is not known if these interventions' effectivity would promote improvements in cardiac autonomic modulation. This study aimed to investigate if a 6-month SIT or a continuous aerobic programme could enhance physical performance and cardiac autonomic modulation at rest, during physical activity (PA) and after it in older adults with an ID. METHODS: This is a randomised control trial. Participants with ID (age: 50.58 ± 7.25) were allocated to one of three groups [multicomponent aerobic training group (MATG), multicomponent interval sprint training group (MISTG) and control group (CG)]. The programmes lasted 24 weeks, with three sessions/week, 75-90 min per session. The HRV was analysed at rest and recovery, the delta of heart rate (HR) was analysed during 6MWT, and the HR t-off kinetics was analysed in recovery after 6MWT. RESULTS: There were not found differences between groups, moments, or interaction for cardiac autonomic modulation at rest and recovery. During exercise, only MSITG showed a significant increase of HR between rest and the first 30 s of exercise (P < 0.05). Physical performance increased only in MSITG (P < 0.05), while CG showed a significant reduction (P < 0.01). CONCLUSIONS: The MSITG improved the physical performance and the vagal withdrawal at the beginning of the submaximal exercise. These findings suggest that high-intensity exercise may positively impact baroreflex function, mitigating the decline in autonomic reflex response capacity associated with aging in individuals with ID.

8.
Annu Rev Phytopathol ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950449

RESUMO

Regenerative agriculture as a term and concept has gained much traction over recent years. Many farmers are convinced that by adopting these principles they will be able to address the triple crisis of biodiversity loss, climate change, and food security. However, the impact of regenerative agriculture practices on crop pathogens and their management has received little attention from the scientific community. Significant changes to cropping systems may result in certain diseases presenting more or less of a threat. Shifts in major diseases may have significant implications regarding optimal integrated pest management (IPM) strategies that aim to improve profitability and productivity in an environmentally sensitive manner. In particular, many aspects of regenerative agriculture change risk levels and risk management in ways that are central to effective IPM. This review outlines some of the challenges, gaps, and opportunities in our understanding of appropriate approaches for managing crop diseases in regenerative cropping systems.

9.
IJTLD Open ; 1(2): 69-75, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38966689

RESUMO

BACKGROUND: We evaluated the palatability and acceptability of a 100 mg dispersible and a non-dispersible 250 mg levofloxacin (LVX) tablet formulation in children. METHODS: Perform was a randomised, open-label, cross-over trial of the relative bioavailability of LVX dispersible vs. crushed non-dispersible tablets in children aged <6 years routinely receiving TB preventive treatment. Children and caregivers completed Likert- and ranking-type measures on the acceptability of both formulations. We used summary, comparative and ranking statistics to characterise formulation acceptability. RESULTS: A total of 25 children were enrolled (median age: 2.6 years, IQR 1.6-4.0). Caregivers reported frequent challenges with preventive therapy in routine care prior to study entry, including taste of tablets (n = 14, 56%), vomiting/spitting out medicines (n = 11, 44%), and children refusing medicines (n = 10, 40%). Caregivers reported that the dispersible formulation was easier for their child to take than the non-dispersible formulation (P = 0.0253). Mean ranks for caregiver's formulation preferences (dispersible tablets: 1.48, SD ±0.71; non-dispersible tablets: 2.12, SD ±0.67; routinely available formulations: 2.40 SD ±0.82) differed significantly (Friedman's F 11.120; P < 0.0038); post-hoc testing showed dispersible tablets were preferred over non-dispersible (P = 0.018) and routinely available LVX formulations (P < 0.001). CONCLUSIONS: The dispersible LVX 100 mg tablet formulation was preferred and should be prioritised for integration into routine care.


CONTEXTE: Nous avons évalué la palatabilité et l'acceptabilité d'un comprimé dispersible de 100 mg et d'un comprimé non dispersible de 250 mg de lévofloxacine (LVX) chez les enfants. MÉTHODES: Perform était un essai randomisé, ouvert et croisé de la biodisponibilité relative des comprimés dispersibles LVX par rapport aux comprimés non dispersibles écrasés chez des enfants âgés de moins de 6 ans recevant régulièrement un traitement préventif contre la TB. Les enfants et les soignants ont rempli des questionnaires de type Likert et de classement sur la tolérance des deux formulations. Nous avons utilisé des statistiques sommaires, comparatives et de classement pour caractériser la tolérance à la formulation. RÉSULTATS: Au total, 25 enfants ont été recrutés (âge médian : 2,6 ans ; IQR 1,6­4,0). Les soignants ont signalé des problèmes fréquents liés au traitement préventif dans le cadre des soins de routine avant le début de l'étude, notamment le goût des comprimés (n = 14, 56%), le fait de vomir ou de recracher les médicaments (n = 11, 44%) et le fait que les enfants refusent les médicaments (n = 10, 40%). Les soignants ont déclaré que la formulation dispersible était plus facile à prendre pour leur enfant que la formulation non dispersible (P = 0,0253). Les classements moyens pour les préférences de formulation des soignants (comprimés dispersibles : 1,48 ; SD ±0,71 ; comprimés non dispersibles : 2,12 ; SD ±0,67 ; formulations couramment disponibles : 2,40 ; SD ±0,82) différaient de manière significative (Friedman's F 11,120 ; P < 0,0038) ; les tests post-hoc ont montré que les comprimés dispersibles étaient préférés aux comprimés non dispersibles (P = 0,018) et aux formulations LVX couramment disponibles (P < 0,001). CONCLUSION: La formulation dispersible des comprimés de LVX 100 mg a été préférée et devrait être intégrée en priorité dans les soins de routine.

10.
Nurse Educ Pract ; 79: 104032, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38964082

RESUMO

AIM: To examine the incorporation of wearable electronic devices in the education of undergraduate nursing students. BACKGROUND: The advancement of technology has influenced nursing education and will continue to do so in the future. Wearable technologies are electronic devices that can be worn as an accessory and expand the possibilities in nursing education with increased engagement in the learning process. DESIGN: A scoping review was conducted following JBI and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) guidelines. METHODS: The search was performed on August 25th, 2023, in the databases: MEDLINE via PubMed, ISI Web of Science, ERIC, EBSCOhost CINAHL, EBSCOhost Academic Search Premier, EBSCOhost Health Source Nursing, EMBASE, Scopus, BVShost LILACS and ProQuest. Literature that examined the application of wearable electronic devices in the education of undergraduate nursing students was included. RESULTS: This scoping review study included a total of 21 records published between 2014 and 2023. The analysis showed that smart glasses are the most common wearable electronic device used in nursing education, followed by smartwatches. The devices provide an opportunity for competencies development, especially when applied in the simulation environment, such as physical examination and medication administration. Wearable technologies are potentially useful and feasible as learning tools in nursing education, increasing nursing students' motivation, confidence and satisfaction. CONCLUSIONS: In the technological revolution, educators must consider the potential of innovative teaching strategies, such as wearable electronic devices, to advance nursing education. Wearables can contribute to developing competencies required for the professionalism of undergraduate nursing students.

11.
Res Sq ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38947070

RESUMO

Background: Epigenetic Age (EA) is an age estimate, developed using DNA methylation (DNAm) states of selected CpG sites across the genome. Although EA and chronological age are highly correlated, EA may not increase uniformly with time. Departures, known as epigenetic age acceleration (EAA), are common and have been linked to various traits and future disease risk. Limited by available data, most studies investigating these relationships have been cross-sectional - using a single EA measurement. However, the recent growth in longitudinal DNAm studies has led to analyses of associations with EA over time. These studies differ in (i) their choice of model; (ii) the primary outcome (EA vs. EAA); and (iii) in their use of chronological age or age-independent time variables to account for the temporal dynamic. We evaluated the robustness of each approach using simulations and tested our results in two real-world examples, using biological sex and birthweight as predictors of longitudinal EA. Results: Our simulations showed most accurate effect sizes in a linear mixed model or generalized estimating equation, using chronological age as the time variable. The use of EA versus EAA as an outcome did not strongly impact estimates. Applying the optimal model in real-world data uncovered an accelerated EA rate in males and an advanced EA that decelerates over time in children with higher birthweight. Conclusion: Our results can serve as a guide for forthcoming longitudinal EA studies, aiding in methodological decisions that may determine whether an association is accurately estimated, overestimated, or potentially overlooked.

12.
BMC Bioinformatics ; 25(1): 231, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38969970

RESUMO

PURPOSE: In this study, we present DeepVirusClassifier, a tool capable of accurately classifying Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) viral sequences among other subtypes of the coronaviridae family. This classification is achieved through a deep neural network model that relies on convolutional neural networks (CNNs). Since viruses within the same family share similar genetic and structural characteristics, the classification process becomes more challenging, necessitating more robust models. With the rapid evolution of viral genomes and the increasing need for timely classification, we aimed to provide a robust and efficient tool that could increase the accuracy of viral identification and classification processes. Contribute to advancing research in viral genomics and assist in surveilling emerging viral strains. METHODS: Based on a one-dimensional deep CNN, the proposed tool is capable of training and testing on the Coronaviridae family, including SARS-CoV-2. Our model's performance was assessed using various metrics, including F1-score and AUROC. Additionally, artificial mutation tests were conducted to evaluate the model's generalization ability across sequence variations. We also used the BLAST algorithm and conducted comprehensive processing time analyses for comparison. RESULTS: DeepVirusClassifier demonstrated exceptional performance across several evaluation metrics in the training and testing phases. Indicating its robust learning capacity. Notably, during testing on more than 10,000 viral sequences, the model exhibited a more than 99% sensitivity for sequences with fewer than 2000 mutations. The tool achieves superior accuracy and significantly reduced processing times compared to the Basic Local Alignment Search Tool algorithm. Furthermore, the results appear more reliable than the work discussed in the text, indicating that the tool has great potential to revolutionize viral genomic research. CONCLUSION: DeepVirusClassifier is a powerful tool for accurately classifying viral sequences, specifically focusing on SARS-CoV-2 and other subtypes within the Coronaviridae family. The superiority of our model becomes evident through rigorous evaluation and comparison with existing methods. Introducing artificial mutations into the sequences demonstrates the tool's ability to identify variations and significantly contributes to viral classification and genomic research. As viral surveillance becomes increasingly critical, our model holds promise in aiding rapid and accurate identification of emerging viral strains.


Assuntos
COVID-19 , Aprendizado Profundo , Genoma Viral , SARS-CoV-2 , SARS-CoV-2/genética , SARS-CoV-2/classificação , Genoma Viral/genética , COVID-19/virologia , Coronaviridae/genética , Coronaviridae/classificação , Humanos , Redes Neurais de Computação
13.
Sci Rep ; 14(1): 15289, 2024 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961137

RESUMO

The limited availability of antivirals for new highly pathogenic strains of virus has become a serious public health. Therefore, news products against these pathogens has become an urgent necessity. Among the multiple sources for news antibiotics and antivirals, insect exudates or their products has become an increasingly frequent option. Insects emerged 350 million years ago and have showed a high adaptability and resistance to the most varied biomes. Their survival for so long, in such different environments, is an indication that they have a very efficient protection against environmental infections, despite not having a developed immune system like mammals. Since the ancient civilizations, the products obtained from the bee have been of great pharmacological importance, being used as antimicrobial, anti-inflammatory, antitumor and several other functions. Investigations of biological activity of propolis have been carried out, mainly in the species Apis mellifera, and its product have showed activity against some important viruses. However, for the Meliponini species, known as stingless bees, there are few studies, either on their chemical composition or on their biological activities. The importance of studying these bees is because they come from regions with native forests, and therefore with many species of plants not yet studied, in addition to which they are regions still free of pesticides, which guarantees a greater fidelity of the obtained data. Previous studies by our group with crude hydroalcoholic extract of propolis demonstrated an intense antiviral activity against Herpes, influenza, and rubella viruses. In this work, we chose to use aqueous extracts, which eliminates the presence of other compounds besides those originally present in propolis, in addition to extracting substances different from those obtained in alcoholic extracts. Therefore, this study aimed to identify, isolate and characterize compounds with antiviral effects from aqueous propolis extracts from Scaptotrigona aff postica, in emerging viruses such as zicavirus, chikungunya, and mayaro virus. The evaluation of the antiviral activity of the crude and purified material was performed by reducing infectious foci in VERO cell cultures. The results obtained with crude propolis, indicate a high reduction of zica virus (64×) and mayaro (128×) when was used 10% v/v of propolis. The reduction of chikungunya virus was of 256 fold, even when was used 5% v/v of propolis. The chemical characterization of the compounds present in the extracts was performed by high-pressure liquid chromatography. Through the purification of propolis by HPLC and mass spectrometry, it was possible to identify and isolate a peak with antiviral activity. This substance showed activity against all viruses tested. When purified fraction was used, the reduction observed was of 16 fold for zicavirus, 32 fold for mayaro virus and 512 fold for chikungunya virus. Likewise, it was observed that the antiviral response was concentration dependent, being more intense when propolis was added 2 h after the viral infection. Now we are carrying out the chemical characterization of the purified compounds that showed antiviral action.


Assuntos
Antivirais , Própole , Própole/farmacologia , Própole/química , Animais , Antivirais/farmacologia , Antivirais/química , Abelhas , Vírus Chikungunya/efeitos dos fármacos , Chlorocebus aethiops , Células Vero
14.
Br J Sociol ; 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38972049

RESUMO

This research note highlights an emerging transdisciplinary research method-photovoice-and why it is particularly suited for sociological studies of children and youth. Traditional social science data collection methods can be limited in their ability to capture both the depth and breadth of childhood experiences and children's perceptions of their experiences. We describe an emerging method, photovoice, that is used more frequently in other disciplines, and its suitability for sociologically studying youth and children. We describe the limitations of traditional social science methods and how photovoice can help overcome some of these limitations. Photovoice engages participants as lived experts who contribute to both the data collection and analysis in an individual and collective manner. Through taking photos and discussing their meaning, participants can share abstract feelings and discuss sensitive topics in an imaginative format and express themselves creatively. We describe how previous research has used photovoice to work with youth from vulnerable circumstances and those who have experienced trauma as well as demonstrate how photovoice is well situated to bolster the tenets of sociological research.

15.
Hear Res ; 450: 109070, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38972084

RESUMO

Cholinergic signaling is essential to mediate the auditory prepulse inhibition (PPI), an operational measure of sensorimotor gating, that refers to the reduction of the acoustic startle reflex (ASR) when a low-intensity, non-startling acoustic stimulus (the prepulse) is presented just before the onset of the acoustic startle stimulus. The cochlear root neurons (CRNs) are the first cells of the ASR circuit to receive cholinergic inputs from non-olivocochlear neurons of the ventral nucleus of the trapezoid body (VNTB) and subsequently decrease their neuronal activity in response to auditory prepulses. Yet, the contribution of the VNTB-CRNs pathway to the mediation of PPI has not been fully elucidated. In this study, we used the immunotoxin anti-choline acetyltransferase (ChAT)-saporin as well as electrolytic lesions of the medial olivocochlear bundle to selectively eliminate cholinergic VNTB neurons, and then assessed the ASR and PPI paradigms. Retrograde track-tracing experiments were conducted to precisely determine the site of lesioning VNTB neurons projecting to the CRNs. Additionally, the effects of VNTB lesions and the integrity of the auditory pathway were evaluated via auditory brain responses tests, ChAT- and FOS-immunohistochemistry. Consequently, we established three experimental groups: 1) intact control rats (non-lesioned), 2) rats with bilateral lesions of the olivocochlear bundle (OCB-lesioned), and 3) rats with bilateral immunolesions affecting both the olivocochlear bundle and the VNTB (OCB/VNTB-lesioned). All experimental groups underwent ASR and PPI tests at several interstimulus intervals before the lesion and 7, 14, and 21 days after it. Our results show that the ASR amplitude remained unaffected both before and after the lesion across all experimental groups, suggesting that the VNTB does not contribute to the ASR. The%PPI increased across the time points of evaluation in the control and OCB-lesioned groups but not in the OCB/VNTB-lesioned group. At the ISI of 50 ms, the OCB-lesioned group exhibited a significant increase in%PPI (p < 0.01), which did not occur in the OCB/VNTB-lesioned group. Therefore, the ablation of cholinergic non-olivocochlear neurons in the OCB/VNTB-lesioned group suggests that these neurons contribute to the mediation of auditory PPI at the 50 ms ISI through their cholinergic projections to CRNs. Our study strongly reinforces the notion that auditory PPI encompasses a complex mechanism of top-down cholinergic modulation, effectively attenuating the ASR across different interstimulus intervals within multiple pathways.

16.
RSC Adv ; 14(29): 20441-20453, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38946775

RESUMO

Herein, unique A-D-A configuration-based molecules (NBD1-NBD7) were designed from the reference compound (NBR) by utilizing the end-capped acceptor modification approach. Various electron-withdrawing units -F, -Cl, -CN, -NO2, -CF3, -HSO3, and -COOCH3, were incorporated into terminals of reference compound to designed NBD1-NBD7, respectively. A theoretical investigation employing the density functional theory (DFT) and time-dependent DFT (TD-DFT) was performed at B3LYP/6-311G(d,p) level. To reveal diverse opto-electronic and photovoltaic properties, the frontier molecular orbitals (FMOs), absorption maxima (λ max), density of states (DOS), exciton binding energy (E b), open-circuit voltage (V oc) and transition density matrix (TDM) analyses were executed at the same functional. Moreover, the global reactivity parameters (GRPs) were calculated using the HOMO-LUMO energy gaps from the FMOs. Significant results were obtained for the designed molecules (NBD1-NBD7) as compared to NBR. They showed lesser energy band gaps (2.024-2.157 eV) as compared to the NBR reference (2.147 eV). The tailored molecules also demonstrated bathochromic shifts in the chloroform (671.087-717.164 nm) and gas phases (623.251-653.404 nm) as compared to NBR compound (674.189 and 626.178 nm, respectively). From the photovoltaic perspectives, they showed promising results (2.024-2.157 V). Furthermore, the existence of intramolecular charge transfer (ICT) in the designed compounds was depicted via their DOS and TDM graphical plots. Among all the investigated molecules, NBD4 was disclosed as the excellent candidate for solar cell applications owing to its favorable properties such as the least band gap (2.024 eV), red-shifted λ max in the chloroform (717.164 nm) and gas (653.404 nm) phases as well as the minimal E b (0.126 eV). This is due to the presence of highly electronegative -NO2 unit at the terminal of electron withdrawing acceptor moiety, which leads to increased conjugation and enhanced the intramolecular charge transfer (ICT) rate. The obtained insights suggested that the designed molecules could be considered as promising materials for potential applications in the realm of OSCs.

17.
Biomacromolecules ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949966

RESUMO

Cholesteric mesophases based on cellulose ethers, such as ethyl cellulose and hydroxypropyl cellulose, have been studied widely for their remarkable ability to display macroscopic structural color. However, the typical time scales involved in the multiscale self-assembly of cholesteric liquid crystals, from individual nanoscale helical arrangements to discrete microscopic domains, and their dependence on the gel's viscoelastic properties remain underexplored. Here, we establish a quantitative relationship between the kinetics of structural color formation after shear deformation and cholesteric order development at the nano- and microscales. Utilizing rheology in tandem with static and time-resolved reflectivity measurements, we underscore the strong influence of polymer diffusivity and chain elasticity on self-assembly kinetics in cholesteric cellulose ether gels. We show that our phenomenological model can be employed to assess the structure-property relationships of multiple polysaccharide systems, elucidating key design guidelines for the development and processing of structurally colored cholesteric mesophases.

18.
BMC Neurol ; 24(1): 224, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943063

RESUMO

BACKGROUND: Neuropsychological symptoms in the Cognitive, Energetic, Behavioural, and Affective (CEBA) domains are common in people with multiple sclerosis (PwMS) and can negatively affect societal participation. The current study aims to investigate whether there are combinations of symptoms in the different CEBA domains that consistently occur together, that is, if there are CEBA profiles that can be identified. If so, this study aims to develop a screening instrument identifying CEBA profiles in PwMS to select the most suitable neuropsychological rehabilitation treatment for a given CEBA profile and consequently improve the societal participation of PwMS. METHODS: This study is an observational, prospective cohort study consisting of 3 phases. Phase 1 focuses on the identification of CEBA profiles in a large sample of PwMS (n = 300). Phase 2 focuses on validating these CEBA profiles through replication of results in a new sample (n = 100) and on the development of the screening instrument. Phase 3 focuses on qualitatively evaluating in a small group of PwMS whether the selected treatment is suitable for the given CEBA profile or whether existing neuropsychological treatments should be adapted to meet the needs of PwMS suffering from symptoms in multiple CEBA domains simultaneously. Primary outcome is the CEBA profile, which will be derived from performance on neuropsychological assessment consisting of tests and questionnaires regarding the CEBA domains using a latent profile analysis. Inclusion criteria include MS diagnosis, sufficient ability in the Dutch language, and an age between 18 and 70 years. DISCUSSION: The results of the current study will contribute to a more comprehensive understanding of the entire spectrum of neuropsychological symptoms in PwMS. Identification of possible CEBA profiles, and accordingly, the development of a screening instrument determining the CEBA profile of PwMS in clinical practice, contributes to the timely referral of PwMS to the most suitable neuropsychological rehabilitation treatment. If necessary, adjustments to existing treatments will be suggested in order to sufficiently meet the needs of PwMS. All of this with the ultimate aim to improve societal participation, and thereby quality of life, of PwMS. TRIAL REGISTRATION: Dutch Central Committee on Research Involving Human Subjects (CCMO) NL83954.042.23; ClinicalTrials.gov NCT06016309.


Assuntos
Esclerose Múltipla , Humanos , Esclerose Múltipla/psicologia , Esclerose Múltipla/complicações , Esclerose Múltipla/diagnóstico , Estudos Prospectivos , Testes Neuropsicológicos/estatística & dados numéricos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Estudos de Coortes
20.
Rev Sci Instrum ; 95(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38921057

RESUMO

Magnetic nanoparticles (MNPs) are used extensively across numerous disciples, with applications including Magnetic Particle Imaging (MPI), targeted hyperthermia, deep brain stimulation, immunoassays, and thermometry. The assessment of MNPs, especially those being designed for MPI, is performed with magnetic particle spectrometers, relaxometers, loop tracers, or similar devices. Despite the many applications and the need for particle assessment, there are few consolidated resources for designing or building such a MNP assessment system. Here, we describe the design and performance of an open-source device capable of spectroscopy, relaxometry, and loop tracing. We show example measurements from the device and quantify the detection sensitivity by measuring a dilution series of Synomag-D 70 nm (from 0.5 mg Fe/ml to 7 ng Fe/ml) with a 10 mT drive field at 23.8 kHz. The device measures 260 pg Fe with SNR = 1 and 1.3 ng at SNR = 5 in spectroscopy mode in under one second of measurement time. The system has a dynamic range of 60 µg to 260 pg Fe without changing the hardware configuration. As an example application, we characterize Synomag-D's relaxation time constant for drive fields 2-18 mT and compare the magnetization responses of two commonly used MNPs.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...