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1.
Nat Cell Biol ; 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39095657

RESUMEN

Circular RNA (circRNA) is covalently closed, single-stranded RNA produced by back-splicing. A few circRNAs have been implicated as functional; however, we lack understanding of pathways that are regulated by circRNAs. Here we generated a pooled short-hairpin RNA library targeting the back-splice junction of 3,354 human circRNAs that are expressed at different levels (ranging from low to high) in humans. We used this library for loss-of-function proliferation screens in a panel of 18 cancer cell lines from four tissue types harbouring mutations leading to constitutive activity of defined pathways. Both context-specific and non-specific circRNAs were identified. Some circRNAs were found to directly regulate their precursor, whereas some have a function unrelated to their precursor. We validated these observations with a secondary screen and uncovered a role for circRERE(4-10) and circHUWE1(22,23), two cell-essential circRNAs, circSMAD2(2-6), a WNT pathway regulator, and circMTO1(2,RI,3), a regulator of MAPK signalling. Our work sheds light on pathways regulated by circRNAs and provides a catalogue of circRNAs with a measurable function.

2.
Cancers (Basel) ; 16(13)2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-39001415

RESUMEN

Gastric cancer (GC) poses notable economic and health burdens in settings where the incidence of disease is prevalent. Some countries have established early screening and treatment programs to address these challenges. The objectives of this systematic review were to summarize the cost-effectiveness of gastric cancer screening presented in the literature and to identify the critical factors that influence the cost-effectiveness of screening. This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Economic evaluation studies of gastric cancer screening were reviewed from SCOPUS and PubMed. The Consolidated Health Economic Evaluation Reporting Standards 2022 (CHEERS 2022) was used to assess the quality of reporting presented in the selected articles. Only primary economic evaluation studies addressing the cost-effectiveness, cost-utility, and cost-benefit of gastric cancer screening were selected. Two reviewers scrutinized the selected articles (title, abstract, and full text) to determine suitability for the systematic review based on inclusion and exclusion criteria. Authors' consensus was relied on where disagreements arose. The main outcome measures of concern in the systematic review were cost, effectiveness (as measured by either quality-adjusted life years (QALY) or life-years saved (LYS)), and incremental cost-effectiveness ratio (ICER) of screening versus either no screening or an alternative screening method. Thirty-one studies were selected for the final review. These studies investigated the cost-effectiveness of GC screening based on either primary, secondary, or a combination of primary and secondary interventions. The main primary intervention was Helicobacter pylori (Hp) screening with eradication, while the main secondary intervention was endoscopic screening. Cost-effectiveness was evaluated against no screening or screening using an alternative method in both observational and model-based studies. Screening was mainly cost-effective in Asian countries or their diasporas where the prevalence of GC was high. GC screening was generally not cost-effective among Western countries. GC screening can be cost-effective, but cost-effectiveness is dependent on context-specific factors, including geographical location, the prevalence of GC in the local population, and the screening tool adopted. However, there is benefit in targeting high-risk population groups in Asian countries and their diaspora for GC screening.

3.
Front Nutr ; 11: 1400513, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38946788

RESUMEN

Introduction: Frequent consumption of ultra-processed foods (UPFs) during pregnancy is linked to excess intake of added sugar, fat, and sodium and inadequacy of several micronutrients. Diet quality during pregnancy should be maximized as inadequate levels of key nutrients and excessive intake of energy and added sugar might influence mother-child health. We aimed to estimate the contribution (% of total calories) of ultra-processed products to the total energy intake by pre-gestational body mass index (BMI) categories and Hb status during pregnancy in participants from the MAS-Lactancia Cohort. Methods: Pre-gestational weight, hemoglobin levels, 24-h dietary intake recall interviews, and sociodemographic data were collected during the second and third trimesters of pregnancy. Reported consumed foods were categorized using the NOVA classification, and the contribution of calories from each NOVA category was estimated using the Mexican Food Database. We estimated medians and interquartile ranges (p25 and p75) for dietary intake and energy contributions. The comparison of intake between the second and third trimesters was done using the Wilcoxon test. In addition, a quantile regression model with an interaction between pre-gestational BMI and Hb levels status in tertiles over the percentage of energy from UPFs was adjusted by age and socioeconomic status. Results: The contribution to total energy intake from UPFs was 27.4% in the second trimester and 27% in the third trimester (with no statistical difference). The percentage of energy intake from UPFs was higher in women who started pregnancy with obesity and presented the lowest levels of Hb (1st tertile), 23.1, 35.8, and 44.7% for the 25th, 50th, and 75th percentiles, respectively, compared to those with normal BMI and the highest tertile of Hb levels: 18, 29.0, and 38.6% for the 25th, 50th, and 75th percentiles, respectively. Conclusion: In conclusion, UPF intake in pregnant women is similar to the general population and was higher for those with pre-gestational obesity and the lowest tertile of Hb levels. UPF contributes also to sugar, saturated fat, and sodium, which may adversely affect the health of mothers and their offspring.

4.
Front Public Health ; 12: 1385058, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39045161

RESUMEN

Background: Prolonged confinement can lead to personal deterioration at various levels. We studied this phenomenon during the nationwide COVID-19 lockdown in a functionally dependent population of the Orcasitas neighborhood of Madrid, Spain, by measuring their ability to perform basic activities of daily living and their mortality rate. Methods: A total of 127 patients were included in the Orcasitas cohort. Of this cohort, 78.7% were female, 21.3% were male, and their mean age was 86 years. All participants had a Barthel index of ≤ 60. Changes from pre- to post-confinement and 3 years afterward were analyzed, and the effect of these changes on survival was assessed (2020-2023). Results: The post-confinement functional assessment showed significant improvement in independence over pre-confinement for both the Barthel score (t = -5.823; p < 0.001) and the classification level (z = -2.988; p < 0.003). This improvement progressively disappeared in the following 3 years, and 40.9% of the patients in this cohort died during this period. These outcomes were associated with the Barthel index (z = -3.646; p < 0.001) and the level of dependence (hazard ratio 2.227; CI 1.514-3.276). Higher mortality was observed among men (HR 1.745; CI 1.045-2.915) and those with severe dependence (HR 2.169; CI 1.469-3.201). Setting the cutoff point of the Barthel index at 40 provided the best detection of the risk of death associated with dependence. Conclusions: Home confinement and the risk of death due to the COVID-19 pandemic awakened a form of resilience in the face of adversity among the population of functionally dependent adults. The Barthel index is a good predictor of medium- and long-term mortality and is a useful method for detecting populations at risk in health planning. A cutoff score of 40 is useful for this purpose. To a certain extent, the non-institutionalized dependent population is an invisible population. Future studies should analyze the causes of the high mortality observed.


Asunto(s)
Actividades Cotidianas , COVID-19 , Humanos , COVID-19/mortalidad , COVID-19/epidemiología , Masculino , España/epidemiología , Femenino , Anciano de 80 o más Años , Estudios Longitudinales , Anciano , Cuarentena , SARS-CoV-2 , Estudios de Cohortes , Control de Enfermedades Transmisibles
5.
Nutrition ; 126: 112493, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-39018986

RESUMEN

OBJECTIVES: Mexico exhibits one of the highest prevalence rates of overweight and obesity globally, accompanied by a surge in non-communicable diseases, which in turn leads to elevated mortality rates. Existing efforts to address rising obesity rates have shown limited effectiveness. Maternal weight, diet, and physical activity (PA) during pregnancy affect the mother's and offspring's health. Despite the importance of establishing and engaging in healthy behaviors during pregnancy, little is known about which factors impact these behaviors among pregnant women in Mexico. This study explored perspectives on factors impacting healthy dietary behaviors and PA in pregnancy from pregnant women and health care professionals in Mexico. METHODS: We conducted semistructured interviews with 11 pregnant women and 12 health care professionals working in prenatal care. Data were analyzed using qualitative content analysis in a stepwise inductive approach. RESULTS: Classifying factors at the 1) individual level, 2) relational level, and 3) health care system level, three overall themes emerged. At the individual level, challenges with lack of time and competing priorities as well as knowledge of healthy dietary behaviors and PA were identified. At the relational level, influencing factors encompassed financial, social, and emotional support along with descriptive norms. At the health care system level, guidelines for PA during pregnancy and the quality of care were noted. CONCLUSIONS: This study identified factors impacting healthy dietary behaviors and PA in pregnancy in Mexico. Important considerations for future interventions include addressing sociocultural norms around healthy dietary behaviors and PA in pregnancy and involving pregnant women's families, closest social networks, and health care professionals working at the prenatal care unit.

6.
Artículo en Inglés | MEDLINE | ID: mdl-39013748

RESUMEN

BACKGROUND AND AIMS: Half of dyslipidemic patients sometimes discontinue statin medication. It is unclear if blood atherogenic risk increases right after statin discontinuation or if there is a lingering protective effect. We sought to determine if a legacy effect prevented blood lipid increases during the first stages of statin cessation. METHODS AND RESULTS: Atherogenic blood lipid profile was measured in 10 overweight (BMI 31 ± 3 kg m-2) middle-aged males (62 ± 7 years old), statin users, while fasted and postprandially. Trials were conducted before (i.e., Day 0) and after 4, 7, 15, and 30 days of statin withdrawal and 20 days after statins reloading (Day 50). Four days after statin discontinuation, blood fasting LDL-c, total cholesterol (CHOL), and triglyceride (TG) concentrations increased by 30%, 18%, and 17%, respectively (P < 0.05). The increases in LDL-c, CHOL, and TG peaked after 7-15 days at 79%, 48%, and 34% of basal levels (P < 0.001), respectively. There were no significant correlations between the increases in blood lipids and the dose or years under statin treatment (P = 0.156-0.575). Twenty days after resuming statins, blood LDL-c (2.79 ± 1.06 vs 2.20 ± 0.50 mmol L-1; P = 0.568), CHOL (4.85 ± 1.41 vs 4.25 ± 0.83 mmol L-1; P = 0.747), and TG (1.47 ± 0.60 vs 1.50 ± 0.68 mmol L-1; P = 0.782), returned to basal levels. CONCLUSIONS: Our data does not support a statin lingering/legacy effect in blood lipids since they dangerously increased after only 4 days of statin withdrawal in every patient, regardless of dose and years under treatment. Reloading statins restored blood lipids, evidencing a reproducible biological effect at the whole-body level.

7.
Aquat Toxicol ; 273: 107005, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38897074

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants ubiquitous in coastal ecosystems. The white shrimp Penaeus vannamei naturally inhabits in coastal areas and is cultivated in farms located nearby the oceans. PAHs can damage shrimp health, endanger natural populations, and lower shrimp aquaculture productivity. However, crustaceans have enzymes capable of metabolizing organic xenobiotics as PAHs and to neutralize reactive oxygen species (ROS) produced during xenobiotics metabolism. An important superfamily of xenobiotic-metabolizing and antioxidant enzymes are glutathione S-transferases (GSTs). In white shrimp, some GSTs are known, but they have been scarcely studied in response to PAHs. In this study we report the molecular cloning and bioinformatic characterization of two novel nucleotide sequences corresponding to cytosolic GSTs belonging the Delta and Theta classes (GSTD and GSTT). Both proteins genes have tissue-specific patterns of expression under normal conditions, that do not necessarily relate to GST activity and glutathione content. The expression of the GSTD and GSTT, GST activity and glutathione content was analyzed in juvenile P. vannamei exposed to two PAHs, naphthalene (NAP) and phenanthrene (PHE) in sub-lethal concentrations for 96 h. GSTD expression was up-regulated by the two PAHs, while GSTT expression was only induced by NAP. In contrast, GST activity towards CDNB was only up-regulated by PHE, suggesting differential effects of PAHs at gene and protein level. On the other hand, lower reduced glutathione content (GSH) caused by PAHs indicates its utilization for detoxification or antioxidant defenses. However, the GSH/GSSG did not change by PAHs treatment, indicating that shrimp can maintain redox balance during short-term sub-lethal exposure to NAP and PHE. Despite the variations in the responses to NAP and PHE, all these results suggest that the GSTD and GSTT genes could be useful biomarkers for PAH exposure in P. vannamei.

8.
Appl Plant Sci ; 12(3): e11598, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38912653

RESUMEN

Premise: Competition from naturalized species and habitat loss are common threats to native biodiversity and may act synergistically to increase competition for decreasing habitat availability. We use Hawaiian dryland ferns as a model for the interactions between land-use change and competition from naturalized species in determining habitat availability. Methods: We used fine-resolution climatic variables and carefully curated occurrence data from herbaria and community science repositories to estimate the distributions of Hawaiian dryland ferns. We quantified the degree to which naturalized ferns tend to occupy areas suitable for native species and mapped the remaining available habitat given land-use change. Results: Of all native species, Doryopteris angelica had the lowest percentage of occurrences of naturalized species in its suitable area while D. decora had the highest. However, all Doryopteris spp. had a higher percentage overlap, while Pellaea ternifolia had a lower percentage overlap, than expected by chance. Doryopteris decora and D. decipiens had the lowest proportions (<20%) of suitable area covering native habitat. Discussion: Areas characterized by shared environmental preferences of native and naturalized ferns may decrease due to human development and fallowed agricultural lands. Our study demonstrates the value of place-based application of a recently developed correlative ecological niche modeling approach for conservation risk assessment in a rapidly changing and urbanized island ecosystem.

9.
Comput Biol Med ; 177: 108586, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38796882

RESUMEN

Segmentation and classification of large numbers of instances, such as cell nuclei, are crucial tasks in digital pathology for accurate diagnosis. However, the availability of high-quality datasets for deep learning methods is often limited due to the complexity of the annotation process. In this work, we investigate the impact of noisy annotations on the training and performance of a state-of-the-art CNN model for the combined task of detecting, segmenting and classifying nuclei in histopathology images. In this context, we investigate the conditions for determining an appropriate number of training epochs to prevent overfitting to annotation noise during training. Our results indicate that the utilisation of a small, correctly annotated validation set is instrumental in avoiding overfitting and maintaining model performance to a large extent. Additionally, our findings underscore the beneficial role of pre-training.


Asunto(s)
Redes Neurales de la Computación , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Aprendizaje Profundo , Núcleo Celular
10.
J Econ Entomol ; 117(3): 1152-1163, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38691142

RESUMEN

The grape berry moth, Paralobesia viteana (Clemens), is an important pest of cultivated grapes in eastern North America. Damage is caused directly by larval feeding of grape clusters and indirectly by increasing fruit susceptibility to fungal and bacterial pathogens. Despite the impact of grape berry moth on grapes being widely recognized, there is a lack of understanding of the influence that different grape cultivars may have on grape berry moth development, reproduction, and population dynamics. In this study, we constructed age-stage 2-sex life tables for grape berry moth fed on 5 grape cultivars: Concord, Niagara, Riesling, Chambourcin, and Vidal, to examine the effects of diet on insect population development, survival, reproduction, and demographic parameters such as net reproductive rate, intrinsic rate of increase, finite rate of increase, and mean generation time. Our findings reveal that grape cultivar significantly influenced the neonate wandering period, larval developmental time, adult and female longevity, pupal weight, adult preoviposition period, oviposition period, mean generation time, age-stage-specific life expectancy, and reproductive value of P. viteana. However, diet type did not affect grape berry moth total fecundity or other demographic parameters. The highest female reproductive value was observed at 30-40 days of age, indicating that control tactics implemented during this time frame would have the greatest impact on reducing population increase. This study provides critical information on the effects of different grape cultivars on grape berry moth development, reproduction, and demography. These insights could lead to the development of management strategies that improve pest control and reduce economic losses in vineyards.


Asunto(s)
Larva , Tablas de Vida , Mariposas Nocturnas , Pupa , Vitis , Animales , Mariposas Nocturnas/crecimiento & desarrollo , Mariposas Nocturnas/fisiología , Larva/crecimiento & desarrollo , Larva/fisiología , Femenino , Masculino , Pupa/crecimiento & desarrollo , Longevidad , Dieta , Reproducción , Rasgos de la Historia de Vida
11.
Can J Public Health ; 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38647638

RESUMEN

OBJECTIVE: Statistically model the likelihood of changes in the activities of daily living (ADLs) over time for three groups of older adults: those on a pension at all time periods, those never on a pension, and those who transition onto a public pension. METHODS: Our study used data from the Canadian Longitudinal Study on Aging (CLSA), a large national survey. We used data from baseline (2010-2015) and the first follow-up wave (2015-2018). We used logistic regression to model the likelihood of ADL changes in males and females by pension receipt status, controlling for several potential confounders and allowing for the impact of public pensions to be modified by baseline income. RESULTS: The magnitudes of the estimates indicated that those who transition to a public pension are less likely to report ADL degradation and more likely to report ADL improvement compared to those with no public pension. In the lowest baseline income group, those who transitioned onto a pension at follow-up had a 15% (male) or 11% (female) lower likelihood of reporting degraded ADL scores compared to those not receiving a pension at follow-up. Those who transitioned onto a pension in the lowest income group were more likely to report an improved ADL score at follow-up. CONCLUSION: Our results could provide evidence for the potential health benefits of more comprehensive guaranteed annual income programs beyond the pension program. The penalty of being low-income was mitigated by the stability of the pension income in terms of ADL improvement or degradation.


RéSUMé: OBJECTIF: Modeler statistiquement la probabilité de changements des activités de la vie quotidienne (AVQ) à travers le temps pour trois groupes d'adultes âgés : ceux qui reçoivent une pension tout le temps, ceux qui ne reçoivent jamais une pension, et ceux qui transitionnent à recevoir une pension pendant la période d'étude. MéTHODES: Notre étude a utilisé les données de l'Étude longitudinale canadienne sur le vieillissement (ÉLCV), une grande enquête nationale. On a utilisé les données de base (2010-2015) et de la première vague (2015-2018). On a utilisé une régression logistique pour modeler la probabilité de changement des AVQ dans les hommes et les femmes par statut de réception de pension, en ajustant plusieurs facteurs de confusion potentielles et pour que l'impact de pensions publiques soient modifiées par le revenu de base. RéSULTATS: La magnitude des estimations a indiqué que ceux qui font une transition à une pension publique sont moins probables de signaler une dégradation des AVQ et plus probables de déclarer une amélioration comparés à ceux qui ne reçoivent pas une pension publique. Parmi le groupe de revenu de base le plus bas, ceux qui ont transitionné à recevoir une pension au suivi avaient 15 % (hommes) ou 11 % (femmes) moins de chance de déclarer une évaluation de AVQ dégradée comparé à ceux qui ne recevaient pas une pension au suivi. Ceux qui ont transitionné à recevoir une pension dans le groupe de revenu de base le plus bas étaient plus probables de déclarer une évaluation de AVQ améliorée au suivi. CONCLUSION: Nos résultats pourraient apporter la preuve pour les avantages potentiels des programmes compréhensifs de revenu garanti qui vont plus loin que les pensions publiques. La pénalité de faire partie du groupe de revenu le plus bas est atténuée par la stabilité des revenus de pension en ce qui concerne l'amélioration ou la dégradation des AVQ.

12.
Artículo en Inglés | MEDLINE | ID: mdl-38583741

RESUMEN

The white shrimp Penaeus (Litopenaeus) vannamei is the most cultivated shrimp worldwide. Compared to other shrimp species, it has higher resistance to adverse conditions. During hypoxia, the shrimp reduces oxygen consumption and adjusts energy metabolism via anaerobic glycolysis, among other strategies. Hexokinase (HK) is the first enzyme of glycolysis and a key regulation point. In mammals and other vertebrates, there are several tissue-specific HK isoforms with differences in expression and enzyme activity. In contrast, crustacean HKs have been relatively little studied. We studied the P. vannamei HK isoforms during hypoxia and reoxygenation. We cloned two HK1 sequences named HK1-long (1455 bp) and HK1-short (1302 bp), and one HK2 (1344 bp). In normoxia, total HK1 expression is higher in hepatopancreas, while HK2 is higher in gills. Severe hypoxia (1 mg/L of DO) after 12 h exposure and 1 h of reoxygenation increased HK1 expression in both organs, but HK2 expression changed differentially. In hepatopancreas, HK2 expression increased in 6 and 12 h of hypoxia but diminished to normoxia levels after reoxygenation. In gills, HK2 expression decreased after 12 h of hypoxia. HK activity increased in hepatopancreas after 12 h hypoxia, opposite to gills. These results indicate that shrimp HK isoforms respond to hypoxia and reoxygenation in a tissue-specific manner. Intracellular glucose levels did not change in any case, showing the shrimp ability to maintain glucose homeostasis during hypoxia.


Asunto(s)
Penaeidae , Animales , Penaeidae/metabolismo , Hexoquinasa/genética , Hexoquinasa/metabolismo , Secuencia de Aminoácidos , Hipoxia/metabolismo , Oxígeno/metabolismo , Isoformas de Proteínas/metabolismo , Glucosa/metabolismo , Hepatopáncreas/metabolismo , Mamíferos/metabolismo
13.
Am J Physiol Endocrinol Metab ; 326(5): E648-E662, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38568152

RESUMEN

We investigated if a bout of exercise in a hot environment (HEAT) would reduce the postprandial hyperglycemia induced by glucose ingestion. The hypothesis was that HEAT stimulating carbohydrate oxidation and glycogen use would increase the disposal of an ingested glucose load [i.e., oral glucose tolerance test (OGTT); 75 g of glucose]. Separated by at least 1 wk, nine young healthy individuals underwent three trials after an overnight fast in a randomized order. Two trials included 50 min of pedaling at 58 ± 5% V̇o2max either in a thermoneutral (21 ± 1°C; NEUTRAL) or in a hot environment (33 ± 1°C; HEAT) eliciting similar energy expenditure (503 ± 101 kcal). These two trials were compared with a no-exercise trial (NO EXER). Twenty minutes after exercise (or rest), subjects underwent an OGTT, while carbohydrate oxidation (CHOxid, using indirect calorimetry) plasma blood glucose, insulin concentrations (i.e., [glucose], [insulin]), and double tracer glucose kinetics ([U-13C] glucose ingestion and [6,6-2H2] glucose infusion) were monitored for 120 min. At rest, [glucose], [insulin], and rates of appearance/disappearance of glucose in plasma (glucose Ra/Rd) were similar among trials. During exercise, heart rate, tympanic temperature, [glucose], glycogen oxidation, and total CHOxid were higher during HEAT than NEUTRAL (i.e., 149 ± 35 vs. 124 ± 31 µmol·kg-1·min-1, P = 0.010). However, during the following OGTT, glucose Rd was similar in HEAT and NEUTRAL trials (i.e., 25.1 ± 3.6 vs. 25.2 ± 5.3 µmol·kg-1·min-1, P = 0.981). Insulin sensitivity (i.e., ISIndexMATSUDA) only improved in NEUTRAL compared with NO EXER (10.1 ± 4.6 vs. 8.8 ± 3.7 au; P = 0.044). In summary, stimulating carbohydrate use with exercise in a hot environment does not improve postprandial plasma glucose disposal or insulin sensitivity in a subsequent OGTT.NEW & NOTEWORTHY Exercise in the heat increases estimated muscle glycogen use. Reduced muscle glycogen after exercise in the heat could increase insulin-mediated glucose uptake during a subsequent oral glucose tolerance test (OGTT). However, plasma glucose kinetics are not improved during the OGTT in response to a bout of exercise in the heat, and insulin sensitivity worsens. Heat stress activates glucose counterregulatory hormones whose actions may linger during the OGTT, preventing increased glucose uptake.


Asunto(s)
Glucemia , Metabolismo de los Hidratos de Carbono , Metabolismo Energético , Ejercicio Físico , Prueba de Tolerancia a la Glucosa , Glucosa , Calor , Humanos , Masculino , Ejercicio Físico/fisiología , Adulto , Adulto Joven , Glucemia/metabolismo , Femenino , Metabolismo de los Hidratos de Carbono/fisiología , Glucosa/metabolismo , Metabolismo Energético/fisiología , Insulina/sangre , Insulina/metabolismo , Oxidación-Reducción , Voluntarios Sanos , Glucógeno/metabolismo , Periodo Posprandial/fisiología , Hiperglucemia/metabolismo , Hiperglucemia/prevención & control
14.
Front Cell Neurosci ; 18: 1347535, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38650656

RESUMEN

Astrocytes represent the most abundant cell type in the brain, where they play critical roles in synaptic transmission, cognition, and behavior. Recent discoveries show astrocytes are involved in synaptic dysfunction during Alzheimer's disease (AD). AD patients have imbalanced cholesterol metabolism, demonstrated by high levels of side-chain oxidized cholesterol known as 27-hydroxycholesterol (27-OH). Evidence from our laboratory has shown that elevated 27-OH can abolish synaptic connectivity during neuromaturation, but its effect on astrocyte function is currently unclear. Our results suggest that elevated 27-OH decreases the astrocyte function in vivo in Cyp27Tg, a mouse model of brain oxysterol imbalance. Here, we report a downregulation of glutamate transporters in the hippocampus of CYP27Tg mice together with increased GFAP. GLT-1 downregulation was also observed when WT mice were fed with high-cholesterol diets. To study the relationship between astrocytes and neurons, we have developed a 3D co-culture system that allows all the cell types from mice embryos to differentiate in vitro. We report that our 3D co-cultures reproduce the effects of 27-OH observed in 2D neurons and in vivo. Moreover, we found novel degenerative effects in astrocytes that do not appear in 2D cultures, together with the downregulation of glutamate transporters GLT-1 and GLAST. We propose that this transporter dysregulation leads to neuronal hyperexcitability and synaptic dysfunction based on the effects of 27-OH on astrocytes. Taken together, these results report a new mechanism linking oxysterol imbalance in the brain and synaptic dysfunction through effects on astrocyte function.

15.
Microbiol Spectr ; 12(4): e0380523, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38426766

RESUMEN

Pasteurella multocida is an upper respiratory tract commensal in several mammal and bird species but can also cause severe disease in humans and in production animals such as poultry, cattle, and pigs. In this study, we performed whole-genome sequencing of P. multocida isolates recovered from a range of human infections, from the mouths of cats, and from wounds on dogs. Together with publicly available P. multocida genome sequences, we performed phylogenetic and comparative genomic analyses. While isolates from cats and dogs were spread across the phylogenetic tree, human infections were caused almost exclusively by subsp. septica strains. Most of the human isolates were capsule type A and LPS type L1 and L3; however, some strains lacked a capsule biosynthesis locus, and some strains contained a novel LPS outer-core locus, distinct from the eight LPS loci that can currently be identified using an LPS multiplex PCR. In addition, the P. multocida strains isolated from human infections contained novel mobile genetic elements. We compiled a curated database of known P. multocida virulence factor and antibiotic resistance genes (PastyVRDB) allowing for detailed characterization of isolates. The majority of human P. multocida isolates encoded a reduced range of iron receptors and contained only one filamentous hemagglutinin gene. Finally, gene-trait analysis identified a putative L-fucose uptake and utilization pathway that was over-represented in subsp. septica strains and may represent a novel host predilection mechanism in this subspecies. Together, these analyses have identified pathogenic mechanisms likely important for P. multocida zoonotic infections.IMPORTANCEPasteurella multocida can cause serious infections in humans, including skin and wound infections, pneumonia, peritonitis, meningitis, and bacteraemia. Cats and dogs are known vectors of human pasteurellosis, transmitting P. multocida via bite wounds or contact with animal saliva. The mechanisms that underpin P. multocida human predilection and pathogenesis are poorly understood. With increasing identification of antibiotic-resistant P. multocida strains, understanding these mechanisms is vital for developing novel treatments and control strategies to combat P. multocida human infection. Here, we show that a narrow range of P. multocida strains cause disease in humans, while cats and dogs, common vectors for zoonotic infections, can harbor a wide range of P. multocida strains. We also present a curated P. multocida-specific database, allowing quick and detailed characterization of newly sequenced P. multocida isolates.


Asunto(s)
Infecciones por Pasteurella , Pasteurella multocida , Humanos , Gatos , Bovinos , Animales , Porcinos , Perros , Pasteurella multocida/genética , Filogenia , Lipopolisacáridos/metabolismo , Infecciones por Pasteurella/veterinaria , Antibacterianos/farmacología , Antibacterianos/metabolismo , Zoonosis , Mamíferos
16.
Int J Mol Sci ; 25(5)2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38474248

RESUMEN

SARS-CoV-2 induces a hyperinflammatory reaction due to the excessive release of cytokines during the immune response. The bacterial endotoxin lipopolysaccharide (LPS) contributes to the low-grade inflammation associated with the metabolic syndrome, enhancing the hyperinflammatory reaction induced by the SARS-CoV-2 infection. The intake of sodium nitrate, a precursor of nitrite and nitric oxide, influences the antioxidant and pro-inflammatory gene expression profile after immune stimulation with LPS in peripheral blood mononuclear cells from metabolic syndrome patients. We aimed to assess the inflammatory and antioxidant responses of immune cells from metabolic syndrome patients to exposure to the SARS-CoV-2 spike protein (S protein) together with LPS and the effect of nitrite in these responses. Whole blood samples obtained from six metabolic syndrome patients were cultured for 16 h at 37 °C with four different media: control medium, control medium plus LPS (100 ng/mL), control medium plus LPS (100 ng/mL) plus S protein (10 ng/mL), and control medium plus LPS (100 ng/mL) plus S protein (10 ng/mL) plus nitrite (5 µM). Immune stimulation with the LPS/S protein enhanced nitrate biosynthesis from nitrite oxidation and probably from additional organic precursors. In vitro incubations with the LPS/S protein enhanced the expression and/or release of pro-inflammatory TNFα, IL-6, IL-1ß, and TLR4, as well as the expression of the anti-inflammatory IL-1ra and IL-10 and antioxidant enzymes. Nitrite attenuated the pro- and anti-inflammatory response induced by the S protein without interfering with the activation of TLR4 and antioxidant enzyme expression, raising the possibility that nitrite could have potential as a coadjutant in the treatment of COVID-19.


Asunto(s)
COVID-19 , Síndrome Metabólico , Glicoproteína de la Espiga del Coronavirus , Humanos , Lipopolisacáridos/farmacología , Nitritos , Antioxidantes/metabolismo , Leucocitos Mononucleares/metabolismo , Activación Enzimática , Receptor Toll-Like 4/metabolismo , SARS-CoV-2/metabolismo , Citocinas/metabolismo , Antiinflamatorios
17.
J Clin Med ; 13(6)2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38541764

RESUMEN

Background: Respiratory tract infections remain among the leading causes of mortality worldwide. The COVID-19 pandemic has highlighted the importance of mucosal immunity in defending against infectious agents. Vitamin A is known to influence the production of secretory immunoglobulin A (SIgA) predominantly in the gut, where it is a critical component of the first line of defense on mucosal surfaces. Methods: This cross-sectional study, conducted 14 days post-positive COVID-19 diagnosis, aimed to determine the relationship between the nutritional status of vitamin A and SIgA levels in COVID-19 outpatients. Serum and saliva samples were collected. Vitamin A nutritional status was determined based on the assessment of dietary intake and the analysis of retinol-binding protein 4 (RBP4). SIgA levels were analyzed from salivary samples. In addition, serum antibodies were analyzed. Results: Dietary vitamin A intake and RBP4 levels positively correlated with SIgA. Patients with higher vitamin A intake showed higher SIgA/IgG1 and SIgA/IgG3 ratios, while those with higher RBP4 levels showed higher SIgA/IgM, SIgA/IgG1, and SIgA/IgG2 ratios. Conclusions: These findings underscore a significant correlation between vitamin A nutritional status and SIgA levels in COVID-19 outpatients, which may suggest the potential importance of maintaining optimal vitamin A levels for the prevention of viral infections.

18.
CJC Open ; 6(2Part B): 436-441, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38487047

RESUMEN

Cardiac rehabilitation is associated with lower mortality and improved psychosocial outcomes. However, disparities exist in referral and access to cardiac rehabilitation for Nova Scotian women, a situation exacerbated by the COVID-19 pandemic. Women@Heart (W@H) is a 4-month community-based peer support program developed and validated by the University of Ottawa Heart Institute, for women living with heart disease. The program aims to empower women with coping strategies, provide a supportive learning environment, and establish volunteer advocacy groups. The primary objective of this study is to evaluate the implementation feasibility of the W@H program for women living in Nova Scotia. The primary outcome is the implementation feasibility of W@H in Nova Scotia, measured through participant attendance and program completion rates. Peer leaders will record participant attendance. The psychosocial impact of W@H will be assessed using psychometric tools that measure the following: social support, adaptive coping, stress, symptoms of anxiety and depression, and health-related and disease-specific quality of life. Data will be collected using a pre- and post-program questionnaire administered to participants. The pilot program is expected to commence in the first quarter of 2024. One peer leader with lived experience of heart disease, who has previously completed the W@H program as a participant, has been trained. Participants have been identified through healthcare provider referral, self-referral, brochures, and peer-networking. Each cohort will consist of 5-10 participants. The W@H pilot project will assess the implementation feasibility and the impact of community-based peer support on the well-being of Nova Scotian women living with heart disease.


La réadaptation cardiaque est associée à une mortalité plus faible et à des bienfaits psychosociaux. Cependant, il existe des disparités en ce qui a trait à l'orientation et à l'accès à la réadaptation cardiaque pour les femmes de la Nouvelle-Écosse, une situation exacerbée par la pandémie de COVID-19. Femmes@Cœur est un programme de soutien collectif par les pairs, créé et validé par l'Institut de cardiologie de l'Université d'Ottawa, à l'intention des femmes atteintes d'une maladies du cœur. Le programme vise à autonomiser les femmes en leur proposant des stratégies d'adaptation, à leur fournir un environnement propice à l'apprentissage et à former des groupes de bénévoles pour la défense de leurs intérêts. La présente étude a pour principal objectif d'évaluer la faisabilité de la mise en œuvre du programme Femmes@Cœur pour les femmes de la Nouvelle-Écosse. Le critère d'évaluation principal de l'étude est la faisabilité de la mise en œuvre du programme Femmes@Cœur en Nouvelle-Écosse, déterminée par la mesure des taux de participation et d'achèvement du programme. Des responsables parmi les pairs consigneront la présence des participantes. Les répercussions psychosociales du programme Femmes@Cœur seront évaluées à l'aide d'outils psychométriques mesurant une gamme de paramètres : soutien social, stratégies d'adaptation, niveau de stress, symptômes d'anxiété et de dépression, et qualité de vie liée à la santé et à la maladie en question. Les données seront recueillies au moyen de questionnaires administrés aux participantes avant et après le programme, et le projet pilote devrait être lancé le premier trimestre de 2024. Une responsable parmi les pairs, elle-même atteinte d'une maladie du cœur et ayant déjà pris part au programme Femmes@Cœur en tant que participante, a été formée à cet effet. Les participantes ont été trouvées de diverses façons : orientation par un professionnel de la santé, inscription spontanée, brochures et réseautage entre pairs. Chaque cohorte sera par ailleurs composée de 5 à 10 participantes. Enfin, le projet pilote Femmes@Cœur évaluera la faisabilité de la mise en œuvre et les répercussions du soutien collectif entre pairs sur le bien-être des femmes de la Nouvelle-Écosse atteintes de maladies cardiaques.

19.
Psychiatry Res ; 335: 115871, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38547600

RESUMEN

Abnormalities in immune function have been described in schizophrenia but few studies have investigated cytokines in cerebrospinal fluid (CSF) and their correlation with blood levels. In this cross-sectional study, cytokines were measured in CSF and plasma of 30 subjects with schizophrenia spectrum disorder (SSD) diagnosis and 23 healthy volunteers (HV). Results showed that CSF TNFα was increased in SSD subjects compared to HV and there were no correlations between CSF and plasma cytokine levels. The present findings provide evidence of dysregulation of TNFα in CSF of schizophrenia. These results identify elevated CSF TNFα levels as a potential biomarker in schizophrenia.


Asunto(s)
Esquizofrenia , Humanos , Citocinas , Factor de Necrosis Tumoral alfa , Estudios Transversales , Biomarcadores/líquido cefalorraquídeo
20.
bioRxiv ; 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38370628

RESUMEN

DNA-PAINT combined with total Internal Reflection Fluorescence (TIRF) microscopy enables the highest localization precisions, down to single nanometers in thin biological samples, due to TIRF's unique method for optical sectioning and attaining high contrast. However, most cellular targets elude the accessible TIRF range close to the cover glass and thus require alternative imaging conditions, affecting resolution and image quality. Here, we address this limitation by applying ultrathin physical cryosectioning in combination with DNA-PAINT. With "tomographic & kinetically-enhanced" DNA-PAINT (tokPAINT), we demonstrate the imaging of nuclear proteins with sub-3 nanometer localization precision, advancing the quantitative study of nuclear organization within fixed cells and mouse tissues at the level of single antibodies. We believe that ultrathin sectioning combined with the versatility and multiplexing capabilities of DNA-PAINT will be a powerful addition to the toolbox of quantitative DNA-based super-resolution microscopy in intracellular structural analyses of proteins, RNA and DNA in situ.

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