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1.
Animals (Basel) ; 14(13)2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38997969

RESUMO

The objective of this exploratory study was to assess if microencapsulated arginine influences the physicochemical quality of beef. The study included three genetic groups: Angus, Hereford, and Angus × Hereford crossbreed. Two encapsulation systems were used with carnauba wax, at ratios of 3:1 and 2:1, carnauba wax:core (arginine), respectively. A control treatment was also included with no arginine addition. Encapsulated arginine with a 3:1 ratio increased redness by 19.66 at 28 d aged beef compared to the control and 2:1 ratio with values of 18.55 and 16.77, respectively (p = 0.01). Encapsulated arginine at a 3:1 ratio showed the lowest meat shear force values with 24.32 N at 28 d of ageing (p < 0.001). The Angus breed also had a low value of 24.02 N (p < 0.001). Finally, the highest values of intramuscular fat were observed with the inclusion of arginine in a 3:1 ratio. The fat value reached 2.12% with a 3:1 ratio (p = 0.002), while in the Angus breed it was 1.59%. The addition of carnauba wax-encapsulated arginine can improve meat quality. It enhances red color, tenderness, and marbling in bovine meat.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38985527

RESUMO

Lead exposure is a severe public health issue that can adversely affect children's neurocognitive development. A semi-urban community in Mexico has been exposed to lead from food cooked in glazed clay pots. A cognitive intervention was conducted from 2015 to 2016 to minimize this negative impact. This intervention aimed to improve the neurocognitive development of the affected children. METHODS: A quasi-experimental study with a control group was conducted in children aged 7 to 12 years from 2 communities in Morelos, Mexico. Blood lead levels were determined, and the neurocognitive function was assessed pre- and postintervention with the Wechsler Intelligence Scale for Children and Children's Auditory Verbal Learning Test-2. A cognitive intervention was conducted at the school. The difference-in-differences method adjusted for variables known as priori and evaluated the impact of cognitive intervention. RESULTS: The differences-in-differences models indicated a significant average increase in scores on the Verbal Comprehension Index (9.58 points), Processing Speed Index (5.33 points), intelligence quotient (5.63 points) level of learning (7.66 points), interference trial (10.12 points), immediate memory span (7.98 points), and recognition accuracy (1.18 points) subtests after the cognitive intervention. CONCLUSION: The results suggest that cognitive intervention improves neurocognitive development in schoolchildren exposed to Pb.

3.
J Inherit Metab Dis ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38973597

RESUMO

The protein encoded by COQ7 is required for CoQ10 synthesis in humans, hydroxylating 3-demethoxyubiquinol (DMQ10) in the second to last steps of the pathway. COQ7 mutations lead to a primary CoQ10 deficiency syndrome associated with a pleiotropic neurological disorder. This study shows the clinical, physiological, and molecular characterization of four new cases of CoQ10 primary deficiency caused by five mutations in COQ7, three of which have not yet been described, inducing mitochondrial dysfunction in all patients. However, the specific combination of the identified variants in each patient generated precise pathophysiological and molecular alterations in fibroblasts, which would explain the differential in vitro response to supplementation therapy. Our results suggest that COQ7 dysfunction could be caused by specific structural changes that affect the interaction with COQ9 required for the DMQ10 presentation to COQ7, the substrate access to the active site, and the maintenance of the active site structure. Remarkably, patients' fibroblasts share transcriptional remodeling, supporting a modification of energy metabolism towards glycolysis, which could be an adaptive mechanism against CoQ10 deficiency. However, transcriptional analysis of mitochondria-associated pathways showed distinct and dramatic differences between patient fibroblasts, which correlated with the extent of pathophysiological and neurological alterations observed in the probands. Overall, this study suggests that the combination of precise genetic diagnostics and the availability of new structural models of human proteins could help explain the origin of phenotypic pleiotropy observed in some genetic diseases and the different responses to available therapies.

4.
Clin Nutr ESPEN ; 63: 304-310, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38976477

RESUMO

BACKGROUND & AIMS: Different nutritional screening tools have been proposed in childhood cancer, but none has shown convincing predictive capacity so far. The "nutrition screening tool for childhood cancer (SCAN)" has been specifically designed for this population and provides an easy-to-use, promising approach to identify patients at risk of malnutrition. We aim to: 1. Validate the SCAN tool prospectively in identifying malnourished patients or those who required nutritional support 2. Validate the SCAN tool prospectively in predicting toxicities or outcome. 3. Compare performance of a pediatric screening tool (STRONGKIDS) with SCAN. METHODS: Children in our center with a new diagnosis of cancer from August 2018 to May 2019 were offered to participate in the study. Measurements (SCAN questionnaire, weight, height, body-mass index (BMI), and mid upper-arm circumference (MUAC)) were taken at diagnosis and at regular intervals throughout therapy. The last measurement was taken 6 months after finishing the intensive treatment phase. SCAN score at diagnosis was validated prospectively against variables of interest. RESULTS: A total of 49 patients were recruited. When considering malnutrition during therapy the SCAN tool showed a sensitivity of 37.5% and negative predictive value (NPV) of 81%. Patients who required nutritional support were identified with a sensitivity of 50% and NPV of 62%. The SCAN tool was not able to predict increased toxicities, risk of relapse or decreased survival. The pediatric screening tool STRONGKIDS was unable to discriminate nutritional risk and labeled all 49 patients (100%) as medium or high-risk. Applying SCAN periodically during therapy increased sensitivity for identifying malnutrition to 87.5%. CONCLUSIONS: In our study, applying the SCAN tool at diagnosis showed low sensitivity in identifying patients who go on to develop malnutrition during therapy. However, patients labeled as "not at risk" were unlikely to need nutritional support in the form of nasogastric tube or total parenteral nutrition. Using SCAN throughout therapy could be helpful in building awareness for malnutrition and successfully discriminates between patients who need further support and those who don't.

5.
BMC Plant Biol ; 24(1): 570, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38886648

RESUMO

BACKGROUND: Sucrose accumulation in sugarcane is affected by several environmental and genetic factors, with plant moisture being of critical importance for its role in the synthesis and transport of sugars within the cane stalks, affecting the sucrose concentration. In general, rainfall and high soil humidity during the ripening stage promote plant growth, increasing the fresh weight and decreasing the sucrose yield in the humid region of Colombia. Therefore, this study aimed to identify markers associated with sucrose accumulation or production in the humid environment of Colombia through a genome-wide association study (GWAS). RESULTS: Sucrose concentration measurements were taken in 220 genotypes from the Cenicaña's diverse panel at 10 (early maturity) and 13 (normal maturity) months after planting. For early maturity data was collected during plant cane and first ratoon, while at normal maturity it was during plant cane, first, and second ratoon. A total of 137,890 SNPs were selected after sequencing the 220 genotypes through GBS, RADSeq, and whole-genome sequencing. After GWAS analysis, a total of 77 markers were significantly associated with sucrose concentration at both ages, but only 39 were close to candidate genes previously reported for sucrose accumulation and/or production. Among the candidate genes, 18 were highlighted because they were involved in sucrose hydrolysis (SUS6, CIN3, CINV1, CINV2), sugar transport (i.e., MST1, MST2, PLT5, SUT4, ERD6 like), phosphorylation processes (TPS genes), glycolysis (PFP-ALPHA, HXK3, PHI1), and transcription factors (ERF12, ERF112). Similarly, 64 genes were associated with glycosyltransferases, glycosidases, and hormones. CONCLUSIONS: These results provide new insights into the molecular mechanisms involved in sucrose accumulation in sugarcane and contribute with important genomic resources for future research in the humid environments of Colombia. Similarly, the markers identified will be validated for their potential application within Cenicaña's breeding program to assist the development of breeding populations.


Assuntos
Estudo de Associação Genômica Ampla , Umidade , Saccharum , Sacarose , Saccharum/genética , Saccharum/metabolismo , Colômbia , Sacarose/metabolismo , Polimorfismo de Nucleotídeo Único , Genótipo
6.
Biochim Biophys Acta Mol Basis Dis ; 1870(7): 167283, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38851305

RESUMO

Obesity represents a significant health challenge, intricately linked to conditions such as type II diabetes, metabolic syndrome, and hepatic steatosis. Several existing obesity treatments exhibit limited efficacy, undesirable side effects or a limited capability to maintain therapeutics effects in the long-term. Recently, modulation Coenzyme Q (CoQ) metabolism has emerged as a promising target for treatment of metabolic syndrome. This potential intervention could involve the modulation of endogenous CoQ biosynthesis by the use of analogs of the precursor of its biosynthesis, such as ß-resorcylic acid (ß-RA). Here, we show that oral supplementation with ß-RA, incorporated into the diet of diet-induced obese (DIO) mice, leads to substantial weight loss. The anti-obesity effects of ß-RA are partially elucidated through the normalization of mitochondrial CoQ metabolism in white adipose tissue (WAT). Additionally, we identify an HFN4α/LXR-dependent transcriptomic activation of the hepatic lipid metabolism that contributes to the anti-obesity effects of ß-RA. Consequently, ß-RA mitigates WAT hypertrophy, prevents hepatic steatosis, counteracts metabolic abnormalities in WAT and liver, and enhances glucose homeostasis by reducing the insulin/glucagon ratio and plasma levels of gastric inhibitory peptide (GIP). Moreover, pharmacokinetic evaluation of ß-RA supports its translational potential. Thus, ß-RA emerges as an efficient, safe, and translatable therapeutic option for the treatment and/or prevention of obesity, metabolic dysfunction-associated steatotic liver disease (MASLD).

7.
J Extracell Biol ; 3(4): e150, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38938847

RESUMO

Extracellular vesicles (EVs) have been proposed to play dual roles in cellular homeostasis, functioning both to remove unwanted intracellular molecules, and to enable communication between cells as a means of modulating cellular responses in different physiological and pathological scenarios. EVs contain a broad range of cargoes, including multiple biotypes of RNA, which can vary depending on the cell status, and may function as signalling molecules. In this study, we carried out comparative transcriptomic analysis of Drosophila EVs and cells, demonstrating that the RNA profile of EVs is distinct from cells and shows dose-dependent changes in response to oxidative stress. We identified a high abundance of snoRNAs in EVs, alongside an enrichment of intronic and untranslated regions (UTRs) of mRNAs under stress. We also observed an increase in the relative abundance of either aberrant or modified mRNAs under stress. These findings suggest that EVs may function both for the elimination of specific cellular RNAs, and for the incorporation of RNAs that may hold signalling potential.

8.
Int J Mol Sci ; 25(11)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38891880

RESUMO

Cordycepin, or 3'-deoxyadenosine, is an adenosine analog with a broad spectrum of biological activity. The key structural difference between cordycepin and adenosine lies in the absence of a hydroxyl group at the 3' position of the ribose ring. Upon administration, cordycepin can undergo an enzymatic transformation in specific tissues, forming cordycepin triphosphate. In this study, we conducted a comprehensive analysis of the structural features of cordycepin and its derivatives, contrasting them with endogenous purine-based metabolites using chemoinformatics and bioinformatics tools in addition to molecular dynamics simulations. We tested the hypothesis that cordycepin triphosphate could bind to the active site of the adenylate cyclase enzyme. The outcomes of our molecular dynamics simulations revealed scores that are comparable to, and superior to, those of adenosine triphosphate (ATP), the endogenous ligand. This interaction could reduce the production of cyclic adenosine monophosphate (cAMP) by acting as a pseudo-ATP that lacks a hydroxyl group at the 3' position, essential to carry out nucleotide cyclization. We discuss the implications in the context of the plasticity of cancer and other cells within the tumor microenvironment, such as cancer-associated fibroblast, endothelial, and immune cells. This interaction could awaken antitumor immunity by preventing phenotypic changes in the immune cells driven by sustained cAMP signaling. The last could be an unreported molecular mechanism that helps to explain more details about cordycepin's mechanism of action.


Assuntos
AMP Cíclico , Desoxiadenosinas , Simulação de Dinâmica Molecular , Neoplasias , Desoxiadenosinas/metabolismo , Desoxiadenosinas/farmacologia , Desoxiadenosinas/química , Humanos , Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/patologia , AMP Cíclico/metabolismo , Trifosfato de Adenosina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Simulação por Computador , Adenilil Ciclases/metabolismo
9.
Electrophoresis ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850174

RESUMO

Selecting an adequate model to represent the mass transfer mechanisms occurring in a chromatographic process is generally complicated, which is one of the reasons why monolithic chromatography is scarcely simulated. In this study, the chromatographic separation of model proteins bovine serum albumin (BSA), ß-lactoglobulin-A, and ß-lactoglobulin-B on an anion exchange monolith was simulated based on experimental parameter determination, simultaneous model testing, and validation under three statistical criteria: retention time, dispersion accuracies, and Pearson correlation coefficient. Experimental characterization of morphologic, physicochemical, and kinetic parameters was performed through volume balances, pressure drop analysis, breakthrough curve analysis, and batch adsorptions. Free Gibbs energy indicated a spontaneous adsorption process for proteins and counterions. Dimensionless numbers were estimated based on height equivalent to a theoretical plate analysis, finding that pore diffusion controlled ß-lactoglobulin separation, whereas adsorption/desorption kinetics was the dominant mechanism for BSA. The elution profiles were modeled using the transport dispersive model and the reactive dispersive model coupled with steric mass action (SMA) isotherms because these models allowed to consider most of the mass transport mechanisms that have been described. RDM-SMA presented the most accurate simulations at pH 6.0 and at low (250 mM) and high (400 mM) NaCl concentrations. This simulation will be used as reference to forecast the purification of these proteins from bovine whey waste and to extrapolate this methodology to other monolith-based separations using these three statistical criteria that have not been used previously for this purpose.

10.
Org Lett ; 26(22): 4695-4699, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38814064

RESUMO

The gold-catalyzed reaction of 2-en-4-ynones with alkynylsilanes provides fully substituted allene derivatives bearing furyl and silyl groups. This transformation would involve generation of a gold furyl carbene intermediate, which regioselectively undergoes a nucleophilic attack by the alkynylsilane at the electrophilic carbene carbon atom with the formation of a ß-gold vinyl cation species. The subsequent release of the gold catalyst, accompanied by a 1,2-silyl shift, leads to the formation of tetrasubstituted allene products.

11.
Cell Rep ; 43(5): 114148, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38697100

RESUMO

Coenzyme Q (CoQ) deficiency syndrome is conventionally treated with limited efficacy using exogenous CoQ10. Poor outcomes result from low absorption and bioavailability of CoQ10 and the clinical heterogenicity of the disease. Here, we demonstrate that supplementation with 4-hydroxybenzoic acid (4HB), the precursor of the benzoquinone ring in the CoQ biosynthetic pathway, completely rescues multisystemic disease and perinatal lethality in a mouse model of CoQ deficiency. 4HB stimulates endogenous CoQ biosynthesis in tissues of Coq2 mutant mice, normalizing mitochondrial function and rescuing cardiac insufficiency, edema, and neurodevelopmental delay. In contrast, exogenous CoQ10 supplementation falls short in fully restoring the phenotype. The treatment is translatable to human use, as proven by in vitro studies in skin fibroblasts from patients with pathogenic variants in COQ2. The therapeutic approach extends to other disorders characterized by deficiencies in the production of 4HB and early steps of CoQ biosynthesis and instances of secondary CoQ deficiency.


Assuntos
Modelos Animais de Doenças , Doenças Mitocondriais , Parabenos , Ubiquinona , Animais , Doenças Mitocondriais/tratamento farmacológico , Doenças Mitocondriais/patologia , Doenças Mitocondriais/metabolismo , Parabenos/farmacologia , Ubiquinona/análogos & derivados , Ubiquinona/farmacologia , Ubiquinona/metabolismo , Ubiquinona/deficiência , Camundongos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Humanos , Fibroblastos/metabolismo , Fibroblastos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Debilidade Muscular/tratamento farmacológico , Debilidade Muscular/metabolismo , Debilidade Muscular/patologia , Ataxia/tratamento farmacológico , Ataxia/patologia , Ataxia/metabolismo
12.
Environ Res ; 255: 119214, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38788790

RESUMO

Several studies have reported immune modulation by organophosphate (OP) pesticides, but the relationship between OP exposure and SARS-CoV-2 infection is yet to be studied. We used two different measures of OP pesticide exposure (urinary biomarkers (N = 154) and residential proximity to OP applications (N = 292)) to examine the association of early-childhood and lifetime exposure to OPs and risk of infection of SARS-CoV-2 using antibody data. Our study population consisted of young adults (ages 18-21 years) from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) Study, a longitudinal cohort of families from a California agricultural region. Urinary biomarkers reflected exposure from in utero to age 5 years. Residential proximity reflected exposures between in utero and age 16 years. SARS-CoV-2 antibodies in blood samples collected between June 2022 and January 2023 were detected via two enzyme linked immunosorbent assays, each designed to bind to different SARS-CoV-2 antigens. We performed logistic regression for each measure of pesticide exposure, adjusting for covariates from demographic data and self-reported questionnaire data. We found increased odds of SARS-CoV-2 infection among participants with higher urinary biomarkers of OPs in utero (OR = 1.94, 95% CI: 0.71, 5,58) and from age 0-5 (OR = 1.90, 95% CI: 0.54, 6.95).


Assuntos
COVID-19 , Exposição Ambiental , Praguicidas , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , Feminino , Adulto Jovem , Adolescente , Exposição Ambiental/efeitos adversos , Praguicidas/urina , Masculino , California/epidemiologia , Gravidez , Adulto , Anticorpos Antivirais/sangue , Biomarcadores/urina , Biomarcadores/sangue , Organofosfatos/urina , Estudos Longitudinais
13.
J Clin Med ; 13(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38731043

RESUMO

(1) Background: The increasing life expectancy brings an increase in geriatric syndromes, specifically frailty. The literature shows that exercise is a key to preventing, or even reversing, frailty in community-dwelling populations. The main objective is to demonstrate how an intervention based on multicomponent exercise produces an improvement in frailty and pre-frailty in a community-dwelling population. (2) Methods: a prospective observational study of a multicomponent exercise program for geriatric revitalization with people aged over 65 holding Barthel Index scores equal to, or beyond, 90. The program was developed over 30 weeks, three times a week, in sessions lasting 45-50 min each. Frailty levels were registered by the Short Physical Performance Battery, FRAIL Questionnaire Screening Tool, and Timed "Up & Go" at the beginning of the program, 30 weeks later (at the end of the program), and following 13 weeks without training; (3) Results: 360 participants completed the program; a greater risk of frailty was found before the program started among older women living in urban areas, with a more elevated fat percentage, more baseline pathologies, and wider baseline medication use. Furthermore, heterogeneous results were observed both in training periods and in periods without physical activity. However, they are consistent over time and show improvement after training. They show a good correlation between TUG and SPPB; (4) Conclusions: A thirty-week multicomponent exercise program improves frailty and pre-frailty status in a community-dwelling population with no functional decline. Nevertheless, a lack of homogeneity is evident among the various tools used for measuring frailty over training periods and inactivity periods.

14.
Dent J (Basel) ; 12(5)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38786536

RESUMO

There is no current consensus on the parameters that determine the difficulty of mandibular third molar extraction in terms of the time required, which is essential to prevent complications and optimize the time of the intervention. This study aims to obtain, using the mathematical method of multiple linear regression, an equation that allows estimating the extraction time of a lower third molar according to its complexity, as well as to validate this equation in a sample of external wisdom teeth. METHODS: A prospective cohort study on a sample of patients of the Master of Oral Surgery of the University of Seville in which multiple linear regression coefficients were calculated with a subsequent validation study of the results in the sample of patients operated in the Hospital Palmaplanas of Mallorca. RESULTS: The regression line obtained after applying the statistical methodology to the cohort of patients from the University of Seville obtained significant dependent variables such as depth, roots, and odontosection. Once applied to the cohort of patients from the Palmaplanas Hospital in Mallorca, a regression coefficient was obtained between the data received and the estimated 0.770. CONCLUSIONS: The formula proposed in this article presents significant validity in the prediction of the surgical time of extraction of the lower third molars included.

15.
J Dent Educ ; 2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38736189

RESUMO

PURPOSE: This study aims to evaluate how student performance and perspectives changed when the Objective Structured Clinical Exam (OSCE) assessment system was changed from a composite score to discipline-specific grading at the Harvard School of Dental Medicine. METHODS: The retrospective study population consisted of all students (n = 349) who completed three OSCEs (OSCE 1, 2, and 3) as part of the predoctoral program during the years 2014-2023. Data on the students' OSCE scores were obtained from the Office of Dental Education, and data on students' race/ethnicity and gender were obtained from their admissions data. RESULTS: The likelihood of a student failing the OSCE after the assessment system change significantly increased with an adjusted odds ratio of 20.12. After the change, the number of failed subjects per student decreased with an adjusted mean ratio of 0.48. Students perceived the OSCE as being less useful after the change. Independent of the grading change, OSCEs 1 and 2 were seen as more useful compared to OSCE 3, which is administered in the last year of the Doctor of Dental Medicine program. CONCLUSION: The discipline-specific nature of the new assessment system helps focus on specific areas of remediation, rather than blanket remediation used previously, in order to isolate the actual areas of deficiency and to focus remediation efforts so that students can align their learning needs appropriately. Therefore, although the actual number of fails identified increased for the course, the assessment change has allowed for more directed, actionable information to be gained from the OSCE to prepare students to work toward competency standards.

16.
Biol Rev Camb Philos Soc ; 99(4): 1481-1503, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38597328

RESUMO

Species are distributed in predictable ways in geographic spaces. The three principal factors that determine geographic distributions of species are biotic interactions (B), abiotic conditions (A), and dispersal ability or mobility (M). A species is expected to be present in areas that are accessible to it and that contain suitable sets of abiotic and biotic conditions for it to persist. A species' probability of presence can be quantified as a combination of responses to B, A, and M via ecological niche modeling (ENM; also frequently referred to as species distribution modeling or SDM). This analytical approach has been used broadly in ecology and biogeography, as well as in conservation planning and decision-making, but commonly in the context of 'natural' settings. However, it is increasingly recognized that human impacts, including changes in climate, land cover, and ecosystem function, greatly influence species' geographic ranges. In this light, historical distinctions between natural and anthropogenic factors have become blurred, and a coupled human-natural landscape is recognized as the new norm. Therefore, B, A, and M (BAM) factors need to be reconsidered to understand and quantify species' distributions in a world with a pervasive signature of human impacts. Here, we present a framework, termed human-influenced BAM (Hi-BAM, for distributional ecology that (i) conceptualizes human impacts in the form of six drivers, and (ii) synthesizes previous studies to show how each driver modifies the natural BAM and species' distributions. Given the importance and prevalence of human impacts on species distributions globally, we also discuss implications of this framework for ENM/SDM methods, and explore strategies by which to incorporate increasing human impacts in the methodology. Human impacts are redefining biogeographic patterns; as such, future studies should incorporate signals of human impacts integrally in modeling and forecasting species' distributions.


Assuntos
Ecossistema , Humanos , Animais , Efeitos Antropogênicos , Modelos Biológicos , Atividades Humanas , Distribuição Animal , Conservação dos Recursos Naturais
17.
J Physiol ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630964

RESUMO

In eukaryotic cells, aerobic energy is produced by mitochondria through oxygen uptake. However, little is known about the early mitochondrial responses to moderate hypobaric hypoxia (MHH) in highly metabolic active tissues. Here, we describe the mitochondrial responses to acute MHH in the heart and skeletal muscle. Rats were randomly allocated into a normoxia control group (n = 10) and a hypoxia group (n = 30), divided into three groups (0, 6, and 24 h post-MHH). The normoxia situation was recapitulated at the University of Granada, at 662 m above sea level. The MHH situation was performed at the High-Performance Altitude Training Centre of Sierra Nevada located in Granada at 2320 m above sea level. We found a significant increase in mitochondrial supercomplex assembly in the heart as soon as the animals reached 2320 m above sea level and their levels are maintained 24 h post-exposure, but not in skeletal muscle. Furthermore, in skeletal muscle, at 0 and 6 h, there was increased dynamin-related protein 1 (Drp1) expression and a significant reduction in Mitofusin 2. In conclusion, mitochondria from the muscle and heart respond differently to MHH: mitochondrial supercomplexes increase in the heart, whereas, in skeletal muscle, the mitochondrial pro-fission response is trigged. Considering that skeletal muscle was not actively involved in the ascent when the heart was beating faster to compensate for the hypobaric, hypoxic conditions, we speculate that the different responses to MHH are a result of the different energetic requirements of the tissues upon MHH. KEY POINTS: The heart and the skeletal muscle showed different mitochondrial responses to moderate hypobaric hypoxia. Moderate hypobaric hypoxia increases the assembly of the electron transport chain complexes into supercomplexes in the heart. Skeletal muscle shows an early mitochondrial pro-fission response following exposure to moderate hypobaric hypoxia.

18.
RSC Adv ; 14(20): 13787-13800, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38681844

RESUMO

Scientists have established a connection between environmental exposure to toxins like ß-N-methylamino-l-alanine (BMAA) and a heightened risk of neurodegenerative disorders. BMAA is a byproduct from certain strains of cyanobacteria that are present in ecosystems worldwide and is renowned for its bioaccumulation and biomagnification in seafood. The sensitivity, selectivity, and reproducibility of the current analytical techniques are insufficient to support efforts regarding food safety and environment monitoring adequately. This work outlines the in vitro selection of BMAA-specific DNA aptamers via the systematic evolution of ligands through exponential enrichment (SELEX). Screening and characterization of the full-length aptamers was achieved using the SYBR Green (SG) fluorescence displacement assay. Aptamers BMAA_159 and BMAA_165 showed the highest binding affinities, with dissociation constants (Kd) of 2.2 ± 0.1 µM and 0.32 ± 0.02 µM, respectively. After truncation, the binding affinity was confirmed using a BMAA-conjugated fluorescence assay. The Kd values for BMAA_159_min and BMAA_165_min were 6 ± 1 µM and 0.63 ± 0.02 µM, respectively. Alterations in the amino proton region studied using solution nuclear magnetic resonance (NMR) provided further evidence of aptamer-target binding. Additionally, circular dichroism (CD) spectroscopy revealed that BMAA_165_min forms hybrid G-quadruplex (G4) structures. Finally, BMAA_165_min was used in the development of an electrochemical aptamer-based (EAB) sensor that accomplished sensitive and selective detection of BMAA with a limit of detection (LOD) of 1.13 ± 0.02 pM.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38605162

RESUMO

It can be challenging to assign patients to the appropriate intervention programs, as risk and protective factors for developing emotional disorders are multiple and shared across disorders. This study aimed to provide a theoretical and empirical approach to identify and categorise adolescents into different levels of severity. The risk of developing emotional symptoms was assessed in 1425 Spanish adolescents (M = 14.34, SD = 1.76; 59.9% women). Latent Profile Analysis (LPA) was conducted to identify subgroups based on their emotional symptom severity, risk, and resilience factors. Results revealed four profiles: at low risk (emotionally healthy), moderate risk (for selective interventions), high risk (for indicated interventions), and severe risk (for clinical referral). Older age and especially female gender were predictors of higher risk clusters, and there were differences in the levels of psychopathology and health-related quality of life across clusters. Identification of at-risk adolescents for emotional disorders by means of LPA may contribute to designing personalised and tailored prevention programs that match adolescents' specific needs.

20.
Electrochim Acta ; 4882024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38654828

RESUMO

Electrochemical impedance spectroscopy (EIS) is a powerful technique for studying the interaction at electrode/solution interfaces. The adoption of EIS for obtaining analytical signals in biosensors based on aptamers is gaining popularity because of its advantageous characteristics for molecular recognition. Neuropeptide Y (NPY), the most abundant neuropeptide in the body, plays a crucial role with its stress-relieving properties. Quantitative measurement of NPY is imperative for understanding its role in these and other biological processes. Although aptamer-modified electrodes for NPY detection using EIS present a promising alternative, the correlation between the data obtained and the adsorption process on the electrodes is not fully understood. Various studies utilize the change in charge transfer resistance when employing an active redox label. In contrast, label-free measurement relies on changes in capacitance. To address these challenges, we focused on the interaction between aptamer-modified planar electrodes and their target, NPY. We proposed utilizing -ω*Zimag as the analytical signal, which facilitated the analysis of the adsorption process using an analogous Langmuir isotherm equation. This approach differs from implantable microelectrodes, which adhere to the Freundlich adsorption isotherm. Notably, our method obviates the need for a redox label and enables the detection of NPY at concentrations as low as 20 pg/mL. This methodology demonstrated exceptional selectivity, exhibiting a signal difference of over 20-to-1 against potential interfering molecules.

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