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1.
Nature ; 615(7952): 436-442, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36922608

RESUMEN

The globally important carbon sink of intact, old-growth tropical humid forests is declining because of climate change, deforestation and degradation from fire and logging1-3. Recovering tropical secondary and degraded forests now cover about 10% of the tropical forest area4, but how much carbon they accumulate remains uncertain. Here we quantify the aboveground carbon (AGC) sink of recovering forests across three main continuous tropical humid regions: the Amazon, Borneo and Central Africa5,6. On the basis of satellite data products4,7, our analysis encompasses the heterogeneous spatial and temporal patterns of growth in degraded and secondary forests, influenced by key environmental and anthropogenic drivers. In the first 20 years of recovery, regrowth rates in Borneo were up to 45% and 58% higher than in Central Africa and the Amazon, respectively. This is due to variables such as temperature, water deficit and disturbance regimes. We find that regrowing degraded and secondary forests accumulated 107 Tg C year-1 (90-130 Tg C year-1) between 1984 and 2018, counterbalancing 26% (21-34%) of carbon emissions from humid tropical forest loss during the same period. Protecting old-growth forests is therefore a priority. Furthermore, we estimate that conserving recovering degraded and secondary forests can have a feasible future carbon sink potential of 53 Tg C year-1 (44-62 Tg C year-1) across the main tropical regions studied.


Asunto(s)
Secuestro de Carbono , Carbono , Conservación de los Recursos Naturales , Bosques , Humedad , Árboles , Clima Tropical , Carbono/metabolismo , Conservación de los Recursos Naturales/métodos , Conservación de los Recursos Naturales/estadística & datos numéricos , Conservación de los Recursos Naturales/tendencias , Árboles/metabolismo , Agricultura Forestal/estadística & datos numéricos , Imágenes Satelitales , Temperatura , Bosque Lluvioso , Borneo , África Central , Brasil
2.
J Immunol ; 212(3): 433-445, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38117781

RESUMEN

Epoxyeicosatrienoic acids (EETs) and other epoxy fatty acids are short-acting lipids involved in resolution of inflammation. Their short half-life, due to its metabolism by soluble epoxide hydrolase (sEH), limits their effects. Specialized proresolving mediators (SPMs) are endogenous regulatory lipids insufficiently synthesized in uncontrolled and chronic inflammation. Using an experimental periodontitis model, we pharmacologically inhibited sEH, examining its impact on T cell activation and systemic SPM production. In humans, we analyzed sEH in the gingival tissue of periodontitis patients. Mice were treated with sEH inhibitor (sEHi) and/or EETs before ligature placement and treated for 14 d. Bone parameters were assessed by microcomputed tomography and methylene blue staining. Blood plasma metabololipidomics were carried out to quantify SPM levels. We also determined T cell activation by reverse transcription-quantitative PCR and flow cytometry in cervical lymph nodes. Human gingival samples were collected to analyze sEH using ELISA and electrophoresis. Data reveal that pharmacological sEHi abrogated bone resorption and preserved bone architecture. Metabololipidomics revealed that sEHi enhances lipoxin A4, lipoxin B4, resolvin E2, and resolvin D6. An increased percentage of regulatory T cells over Th17 was noted in sEHi-treated mice. Lastly, inflamed human gingival tissues presented higher levels and expression of sEH than did healthy gingivae, being positively correlated with periodontitis severity. Our findings indicate that sEHi preserves bone architecture and stimulates SPM production, associated with regulatory actions on T cells favoring resolution of inflammation. Because sEH is enhanced in human gingivae from patients with periodontitis and connected with disease severity, inhibition may prove to be an attractive target for managing osteolytic inflammatory diseases.


Asunto(s)
Resorción Ósea , Periodontitis , Humanos , Animales , Ratones , Microtomografía por Rayos X , Periodontitis/metabolismo , Inflamación , Eicosanoides , Epóxido Hidrolasas/metabolismo
3.
Oncologist ; 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38944844

RESUMEN

INTRODUCTION: Lung cancer in never-smoker (LCINS) patients accounts for 20% of lung cancer cases, and its biology remains poorly understood, particularly in genetically admixed populations. We elucidated the molecular profile of driver genes in Brazilian LCINS. METHODS: The mutational and gene fusion status of 119 lung adenocarcinomas from self-reported never-smoker patients, was assessed using targeted sequencing (NGS), nCounter, and immunohistochemistry. A panel of 46 ancestry-informative markers determined patients' genetic ancestry. RESULTS: The most frequently mutated gene was EGFR (49.6%), followed by TP53 (39.5%), ALK (12.6%), ERBB2 (7.6%), KRAS (5.9%), PIK3CA (1.7%), and less than 1% alterations in RET, NTRK1, MET∆ex14, PDGFRA, and BRAF. Except for TP53 and PIK3CA, all other alterations were mutually exclusive. Genetic ancestry analysis revealed a predominance of European (71.1%), and a higher African ancestry was associated with TP53 mutations. CONCLUSION: Brazilian LCINS exhibited a similar molecular profile to other populations, except the increased ALK and TP53 alterations. Importantly, 73% of these patients have actionable alterations that are suitable for targeted treatments.

4.
Annu Rev Phys Chem ; 74: 467-492, 2023 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-36854178

RESUMEN

We review our recent quantum stochastic model for spectroscopic lineshapes in the presence of a coevolving and nonstationary background population of excitations. Starting from a field theory description for interacting bosonic excitons, we derive a reduced model whereby optical excitons are coupled to an incoherent background via scattering as mediated by their screened Coulomb coupling. The Heisenberg equations of motion for the optical excitons are then driven by an auxiliary stochastic population variable, which we take to be the solution of an Ornstein-Uhlenbeck process. Here, we present an overview of the theoretical techniques we have developed as applied to predicting coherent nonlinear spectroscopic signals. We show how direct (Coulomb) and exchange coupling to the bath give rise to distinct spectral signatures and discuss mathematical limits on inverting spectral signatures to extract the background density of states.

5.
BJU Int ; 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38520403

RESUMEN

OBJECTIVE: This review investigates the prevalence of male non-neurogenic lower urinary tract symptoms (LUTS) after renal transplant, as kidney transplantation is a transformative intervention for patients with end-stage renal disease significantly enhancing quality of life that might be diminished by LUTS. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. A systematic search in the PubMed and Scopus databases was performed using specific terms. Inclusion criteria considered male kidney transplant recipients, analysing outcomes in English-language studies. Discrepancies were resolved by consultation. RESULTS: Among 18 studies involving 29 086 recipients, the prevalence of non-neurogenic LUTS ranged from 5.8% to 33.0%. Studies predominantly used the International Prostate Symptom Score for evaluation. Surgical interventions, mostly for benign prostatic obstruction, ranged from 2.5% to 20.0%. Voiding and post-micturition symptoms were under-represented. CONCLUSION: This review found varied non-neurogenic LUTS prevalence and characteristics in male kidney transplant recipients, emphasising the need for standardised assessments, prospective studies, and improved understanding of LUTS mechanisms. Enhanced knowledge can guide interventions, additionally benefiting recipient quality of life.

6.
BMC Infect Dis ; 24(1): 652, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38943078

RESUMEN

BACKGROUND: Human T-cell lymphotropic virus type 1 (HTLV-1), also denominated Human T-cell leukemia virus-1, induces immune activation and secretion of proinflammatory cytokines, especially in individuals with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Regulatory T lymphocytes (Tregs) may control of inflammation through the production of regulatory cytokines, including IL10 and TGF-ß. In this study we determined the frequencies of CD4 + and CD8 + Tregs in a HAM/TSP population, compared to asymptomatic carriers and uninfected individuals, as well as investigated the profiles of regulatory and inflammatory cytokines. METHODS: Asymptomatic HTLV-1 carriers and HAM/TSP patients were matched by sex and age. The frequencies of IL10- and/or TGF-ß-producing Tregs were quantified by flow cytometry. Real-time reverse transcription polymerase chain reaction (RT-PCR) was used to quantify HTLV-1 proviral load and the mRNA expression of cytokines and cellular receptors in peripheral blood mononuclear cells. RESULTS: Total frequencies of CD4 + Tregs, as well as the IL10-producing CD4 + and CD8 + Treg subsets, were statistically higher in patients with HAM/TSP compared to asymptomatic HTLV-1-infected individuals. In addition, a positive correlation was found between the frequency of CD4 + IL10 + Tregs and proviral load in the HAM/TSP patients evaluated. A positive correlation was also observed between gene expression of proinflammatory versus regulatory cytokines only in HAM / TSP group. CONCLUSIONS: A higher frequencies of IL10-producing Tregs were identified in patients with HAM/TSP. Imbalanced production of IL10 in relation to TGF-ß may contribute to the increased inflammatory response characteristically seen in HAM/TSP patients.


Asunto(s)
Virus Linfotrópico T Tipo 1 Humano , Interleucina-10 , Paraparesia Espástica Tropical , Linfocitos T Reguladores , Factor de Crecimiento Transformador beta , Humanos , Linfocitos T Reguladores/inmunología , Masculino , Femenino , Paraparesia Espástica Tropical/inmunología , Paraparesia Espástica Tropical/virología , Interleucina-10/inmunología , Interleucina-10/genética , Persona de Mediana Edad , Virus Linfotrópico T Tipo 1 Humano/inmunología , Factor de Crecimiento Transformador beta/metabolismo , Adulto , Carga Viral , Anciano , Infecciones por HTLV-I/inmunología , Infecciones por HTLV-I/virología , Portador Sano/inmunología , Portador Sano/virología
7.
Neurourol Urodyn ; 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38934484

RESUMEN

INTRODUCTION: Despite advancements in the treatment of benign prostatic hyperplasia (BPH), the mechanisms underlying BPH development and progression remain elusive and lacks a one-size-fits-all therapeutic solution. Prostatic inflammation contributes to BPH and lower urinary tract symptoms (LUTS), but the initial trigger remains unknown. Current research suggests dysbiosis of the urinary microbiome as a potential culprit. This systematic review explores the emerging field of the male urinary and prostatic microbiome and its relationship with BPH/LUTS. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. A systematic search in the Pubmed and Scopus databases was performed using specific terms. Inclusion criteria considered male non-neurogenic patients with LUTS due to BPH with analyses of urinary microbiome, concerning evaluation of English-language publications with relevance. RESULTS: Among seven articles involving 542 patients, there was an association between male LUTS/BPH and the urinary microbiome. Findings indicate a correlation between urinary microbiome dysbiosis and LUTS severity, with specific bacterial genera such as Streptococcus and Haemophilus linked to higher International Prostate Symptom Score (IPSS) scores and PSA levels. The fecal microbiome may be associated with LUTS, although contradictory findings are reported. The review also highlights methodological inconsistencies, small sample sizes, few negative controls and a lack of comprehensive clinical data as major limitations. CONCLUSIONS: While there is an undeniable correlation between the microbiome and LUTS/BPH, future research should aim to standardize sampling techniques and expand the score to include functional microbiome characterization, potentially leading to novel, microbiome-targeted therapeutic strategies for BPH.

8.
Anal Bioanal Chem ; 416(5): 1217-1227, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38180497

RESUMEN

Thin films of conjugated polymer and enzyme can be used to unravel the interaction between components in a biosensor. Using artificial neural networks (ANNs) improves data interpretability and helps construct models with great capacity for classifying and processing information. The present work used kinetic data from the catalytic activity of urease immobilized in different conjugated polymers to create ANN models using time, substrate concentration, and absorbance as input variables since the models had absorbance in a posterior instant as output value to explore the predictivity of the ANNs. The performance of the models was evaluated by Pearson's correlation coefficient (ρ) and mean squared error (MSE) values. After the learning process, a series of new experiments were performed to verify the generality of the models. As the main results, the best ANN model presented 0.9980 and 3.0736 × 10-5 for ρ and MSE, respectively. For the simulation step, intermediary values of substrate concentration were used. The mean absolute percentage error (MAPE) values were 3.34, 3.07, and 3.78 for 12 mM, 22 mM, and 32 mM concentrations, respectively. Overall, with the simulations, it was possible to ascertain the interpolatory capacity of the model, which has a learning mechanism based on absorbance and time as variables. Thus, the potential of ANNs would be in their use in pre-evaluations, helping to determine the substrate concentration at which there is higher catalytic activity or in determining the linear range of the sensor.


Asunto(s)
Técnicas Biosensibles , Ureasa , Redes Neurales de la Computación , Simulación por Computador , Aprendizaje
9.
Environ Res ; 249: 118345, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38331147

RESUMEN

Strategies seeking to increase the use efficiency of nitrogen (N) fertilizers and that benefit plant growth through multiple mechanisms can reduce production costs and contribute to more sustainable agriculture free of polluting residues. Under controlled conditions, we investigated the compatibility between foliar inoculation with an endophytic diazotrophic bacterium (Herbaspirillum seropedicae HRC54) at control and low, medium and high N fertilization levels (0, 25, 50 and 100 mg of N kg-1 as urea, respectively) in Marandu palisadegrass. Common procedures in our research field (biometric and nutritional assessments) were combined with isotopic techniques (natural abundance - δ15N‰ and 15N isotope dilution) and root scanning to determine the contribution of fixed N and recovery of N fertilizer by the grass. Overall, the combined use of 15N isotopic techniques revealed that inoculation not only improved the recovery of applied N-urea from the soil but also provided fixed nitrogen to Marandu palisade grass, resulting in an increase in the total accumulated N. When inoculated plants grew at control and low levels of N, a positive cascade effect encompassing root growth stimulation (nodes of smaller diameter roots), better soil and fertilizer resource exploitation and increased forage production was observed. In contrast, increasing N reduced the contributions of N fixed by H. seropedicae from 21.5% at the control level to 8.6% at the high N level. Given the minimal to no observed growth promotion, this condition was deemed inhibitory to the positive effects of H. seropedicae. We discuss how to make better use of H. seropedicae inoculation in Marandu palisadegrass, albeit on a small scale, thus contributing to a more rational and efficient use of N fertilizers. Finally, we pose questions for future investigations based on 15N isotopic techniques under field conditions, which have great applicability potential.


Asunto(s)
Fertilizantes , Herbaspirillum , Isótopos de Nitrógeno , Nitrógeno , Raíces de Plantas , Herbaspirillum/metabolismo , Raíces de Plantas/microbiología , Raíces de Plantas/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Nitrógeno/metabolismo , Poaceae/microbiología , Poaceae/metabolismo , Poaceae/crecimiento & desarrollo
10.
Oral Dis ; 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38720642

RESUMEN

OBJECTIVE: To perform a systematic review with meta-analysis to assess recent scientific evidence on the association between periodontitis and systemic parameters/conditions in individuals with chronic kidney disease (CKD). MATERIALS AND METHODS: The search for studies was performed in MedLine/PubMed, Scopus, Web of Science, and BIREME databases. Reference lists of selected articles were also searched. Studies with different epidemiological designs evaluating the influence of exposure to periodontitis on serum markers and mortality in individuals with CKD were eligible for inclusion. Three independent reviewers performed the article selection and data extraction. The assessment of methodological quality used the adapted Newcastle Ottawa Scale. Random effects meta-analysis was performed to calculate association measurements and 95% confidence intervals. RESULTS: In total, 3053 records were identified in the database search, with only 25 studies meeting the eligibility criteria and, of these, 10 studies contributed data for meta-analysis. Using a random-effects model, periodontitis was associated with hypoalbuminemia (PRunadjusted = 2.47; 95%CI:1.43-4.26), with high levels of C-reactive protein (PRunadjusted = 1.35; 95%CI%:1.12-1.64), death from cardiovascular disease (RRunadjusted = 2.29; 95%CI:1.67-3.15) and death from all causes (RRunadjusted = 1.73; 95%CI:1.32-2.27). CONCLUSIONS: The findings of this review validated a positive association between periodontitis and serum markers and mortality data in individuals with CKD.

11.
Int J Mol Sci ; 25(10)2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38791103

RESUMEN

Menopause is characterized by a reduction in sex hormones in women and is associated with metabolic changes, including fatty liver and insulin resistance. Lifestyle changes, including a balanced diet and physical exercise, are necessary to prevent these undesirable changes. Strength training (ST) has been widely used because of the muscle and metabolic benefits it provides. Our study aims to evaluate the effects of ST on hepatic steatosis and insulin resistance in ovariectomized mice fed a high-fat diet (HFD) divided into four groups as follows: simulated sedentary surgery (SHAM-SED), trained simulated surgery (SHAM-EXE), sedentary ovariectomy (OVX-SED), and trained ovariectomy (OVX-EXE). They were fed an HFD for 9 weeks. ST was performed thrice a week. ST efficiently reduced body weight and fat percentage and increased lean mass in OVX mice. Furthermore, ST reduced the accumulation of ectopic hepatic lipids, increased AMPK phosphorylation, and inhibited the de novo lipogenesis pathway. OVX-EXE mice also showed a better glycemic profile, associated with greater insulin sensitivity identified by the euglycemic-hyperinsulinemic clamp, and reduced markers of hepatic oxidative stress compared with sedentary animals. Our data support the idea that ST can be indicated as a non-pharmacological treatment approach to mitigate metabolic changes resulting from menopause.


Asunto(s)
Dieta Alta en Grasa , Hígado Graso , Resistencia a la Insulina , Ovariectomía , Entrenamiento de Fuerza , Animales , Femenino , Ovariectomía/efectos adversos , Dieta Alta en Grasa/efectos adversos , Ratones , Hígado Graso/metabolismo , Hígado Graso/prevención & control , Condicionamiento Físico Animal , Estrés Oxidativo , Hígado/metabolismo , Ratones Endogámicos C57BL , Peso Corporal , Lipogénesis
12.
J Environ Manage ; 352: 119921, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38219661

RESUMEN

Tropical rainforests of Latin America (LATAM) are one of the world's largest carbon sinks, with substantial future carbon sequestration potential and contributing a major proportion of the global supply of forest carbon credits. LATAM is poised to contribute predominantly towards high-quality forest carbon offset projects designed to reduce emissions from deforestation and forest degradation, halt biodiversity loss, and provide equitable conservation benefits to people. Thus, carbon markets, including compliance carbon markets and voluntary carbon markets continue to expand in LATAM. However, the extent of the growth and status of forest carbon markets, pricing initiatives, stakeholders, amongst others, are yet to be explored and extensively reviewed for the entire LATAM region. Against this backdrop, we reviewed a total of 299 articles, including peer-reviewed and non-scientific gray literature sources, from January 2010 to March 2023. Herein, based on the extensive literature review, we present the results and provide perspectives classified into five categories: (i) the status and recent trends of forest carbon markets (ii) the interested parties and their role in the forest carbon markets, (iii) the measurement, reporting and verification (MRV) approaches and role of remote sensing, (iv) the challenges, and (v) the benefits, opportunities, future directions and recommendations to enhance forest carbon markets in LATAM. Despite the substantial challenges, better governance structures for forest carbon markets can increase the number, quality and integrity of projects and support the carbon sequestration capacity of the rainforests of LATAM. Due to the complex and extensive nature of forest carbon projects in LATAM, emerging technologies like remote sensing can enable scale and reduce technical barriers to MRV, if properly benchmarked. The future directions and recommendations provided are intended to improve upon the existing infrastructure and governance mechanisms, and encourage further participation from the public and private sectors in forest carbon markets in LATAM.


Asunto(s)
Carbono , Ecosistema , Humanos , Carbono/metabolismo , América Latina , Conservación de los Recursos Naturales/métodos , Bosques , Secuestro de Carbono
13.
Medicina (Kaunas) ; 60(5)2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38793013

RESUMEN

(1) Background and objectives: Maturity-onset diabetes of the young (MODY) is a group of diabetes caused by gene defects related to insulin secretion. MODY1, MODY2, and MODY3 are the most common and account for approximately 80% of all cases. Other types are relatively rare. This study describes the clinical, analytical, and genetic characteristics of a patient with MODY10, and diabetic nephropathy, retinopathy, and functional hypogonadism diagnosis. (2) Materials and methods: A clinical case was analyzed and whole exome generation sequencing (WES) was used to detect mutations related to a monogenic variant. (3) Results: A seventeen-year-old male patient, who was diagnosed with apparent type 1 diabetes at the age of eight was started with insulin therapy. He came to the emergency room with glycemic decompensation, facial, and lower limb edema. During his evaluation, he had near-nephrotic range proteinuria of 2902 mg/24 h, a kidney ultrasound showing mild pyelocalyceal dilation, proliferative diabetic retinopathy, and was also diagnosed with functional hypogonadotropic hypogonadism. These comorbidities improved with adequate glycemic control. WES showed missense variant c.94G>A (p.Gly32Ser) in the INS gene, according to Clinvar corresponding to MODY10. It was a "de novo" variant not reported in his parents. (4) Conclusions: Monogenic diabetes (MD) is rare and MODY10 is among the less frequent types. MODY should be suspected in patients with type 1 phenotype with negative autoimmunity even in the absence of a family history of diabetes. To the best of our knowledge, we present here the first patient with these phenotypic traits of MODY10 reported in Latin America.


Asunto(s)
Diabetes Mellitus Tipo 2 , Nefropatías Diabéticas , Retinopatía Diabética , Hipogonadismo , Humanos , Masculino , Retinopatía Diabética/genética , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/genética , Hipogonadismo/genética , Hipogonadismo/complicaciones , Adolescente , Nefropatías Diabéticas/genética , Nefropatías Diabéticas/complicaciones
14.
Clin Immunol ; 251: 109321, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37019421

RESUMEN

This study described a soluble mediator storm in acute Yellow Fever/YF infection along the kinetics timeline towards convalescent disease. The analyses of the YF Viral RNAnemia, chemokines, cytokines, and growth factors were performed in YF patients at acute/(D1-15) and convalescent/(D16-315) phases. Patients with acute YF infection displayed a trimodal viremia profile spreading along D3, D6, and D8-14. A massive storm of mediators was observed in acute YF. Higher levels of mediators were observed in YF with higher morbidity scores, patients under intensive care, and those progressing to death than in YF patients who progress to late-relapsing hepatitis/L-Hep. A unimodal peak of biomarkers around D4-6 with a progressive decrease towards D181-315 was observed in non-L-Hep patients, while a bimodal pattern with a second peak around D61-90 was associated with L-Hep. This study provided a comprehensive landscape of evidence that distinct immune responses drive pathogenesis, disease progression, and L-Hep in YF patients.


Asunto(s)
Hepatitis , Vacuna contra la Fiebre Amarilla , Fiebre Amarilla , Humanos , Fiebre Amarilla/patología , Pronóstico , Citocinas , Biomarcadores
15.
Reproduction ; 166(6): 459-471, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37855440

RESUMEN

In brief: The SCN regulates ovulation by stimulating the preovulatory surge of gonadotropins. This study revealed an additional role in the sensitization of the hypothalamus to estradiol that changes along the estrous cycle and the side of the nucleus. Abstract: Ovulation is timed by neural signals originating at the suprachiasmatic nucleus (SCN) that trigger ovulation when converge with high estradiol levels, which indicates the maturation of ovarian follicles. We have shown that the hypothalamic regulation of ovulation is asymmetrical and we hypothesized that the paired SCN could contribute to such symmetries. We unilaterally lesioned the SCN of rats at each stage of the estrous cycle and evaluated the acute effects on the progression of their estrous cycle, follicular development and ovulation. Lesions prevented progression of the estrous cycle when performed in estrus/metestrus but not in diestrus/proestrus. Abnormalities in follicular development were observed in the nonovulating lesioned rats and this was independent of the side of the SCN destroyed and the stage of the cycle when surgery was performed. Groups of lesioned rats were then hormonally primed with GnRH or estradiol to assess the neuroendocrine pathway altered by the treatment. GnRH restored ovulation, suggesting that both SCN are needed for proper triggering of the preovulatory surge of GnRH and that unilateral lesion does not impair the sensitivity of the pituitary or the ovary to GnRH and gonadotropins, respectively. With regard to restoring ovulation, estradiol was asymmetrically effective in rats lesioned in estrous, partially effective in rats operated at diestrus and ineffective in rats at metestrus. Our results indicate that the SCN regulates the activity of the hypothalamic-pituitary-ovarian axis not only by modulating the preovulatory surge of GnRH/gonadotropins but also by promoting the hypothalamic integration of estrogenic signals from the ovaries in an asymmetric and stage-dependent fashion.


Asunto(s)
Estradiol , Ciclo Estral , Femenino , Ratas , Animales , Estradiol/farmacología , Retroalimentación , Núcleo Supraquiasmático/metabolismo , Hormona Liberadora de Gonadotropina/metabolismo , Ovulación , Gonadotropinas/farmacología
16.
Cell Mol Neurobiol ; 43(3): 1163-1180, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35674974

RESUMEN

Methylmalonic acidemia is an organic acidemia caused by deficient activity of L-methylmalonyl-CoA mutase or its cofactor cyanocobalamin and it is biochemically characterized by an accumulation of methylmalonic acid (MMA) in tissue and body fluids of patients. The main clinical manifestations of this disease are neurological and observable symptoms during metabolic decompensation are encephalopathy, cerebral atrophy, coma, and seizures, which commonly appear in newborns. This study aimed to investigate the toxic effects of MMA in a glial cell line presenting astrocytic features. Astroglial C6 cells were exposed to MMA (0.1-10 mM) for 24 or 48 h and cell metabolic viability, glucose consumption, and oxygen consumption rate, as well as glutamate uptake and ATP content were analyzed. The possible preventive effects of bezafibrate were also evaluated. MMA significantly reduced cell metabolic viability after 48-h period and increased glucose consumption during the same period of incubation. Regarding the energy homeostasis, MMA significantly reduced respiratory parameters of cells after 48-h exposure, indicating that cell metabolism is compromised at resting and reserve capacity state, which might influence the cell capacity to meet energetic demands. Glutamate uptake and ATP content were also compromised after exposure to MMA, which can be influenced energy metabolism impairment, affecting the functionality of the astroglial cells. Our findings suggest that these effects could be involved in the pathophysiology of neurological dysfunction of this disease. Methylmalonic acid compromises mitochondrial functioning leading to reduced ATP production and reduces glutamate uptake by C6 astroglial cells.


Asunto(s)
Glioma , Ácido Glutámico , Ratas , Animales , Ácido Glutámico/metabolismo , Ácido Metilmalónico/toxicidad , Respiración de la Célula , Adenosina Trifosfato/metabolismo
17.
Curr Genomics ; 24(5): 330-335, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38235354

RESUMEN

Background: Dysferlinopathies represent a group of limb girdle or distal muscular dystrophies with an autosomal-recessive inheritance pattern resulting from the presence of pathogenic variants in the dysferlin gene (DYSF). Objective: In this work, we describe a population from a small city in Brazil carrying the c.5979dupA pathogenic variant of DYSF responsible for limb girdle muscular dystrophy type 2R and distal muscular dystrophy. Methods: Genotyping analyses were performed by qPCR using customized probe complementary to the region with the duplication under analysis in the DYSF. Results: A total of 104 individuals were examined. c.5979dupA was identified in 48 (46.15%) individuals. Twenty-three (22%) were homozygotes, among whom 13 (56.5%) were female. A total of 91.3% (21) of homozygous individuals had a positive family history, and seven (30.4%) reported consanguineous marriages. Twenty-five (24%) individuals were heterozygous (25.8±16 years) for the same variant, among whom 15 (60%) were female. The mean CK level was 697 IU for homozygotes, 140.5 IU for heterozygotes and 176 IU for wild-type homo-zygotes. The weakness distribution pattern showed 17.3% of individuals with a proximal pattern, 13% with a distal pattern and 69.6% with a mixed pattern. Fatigue was present in 15 homozygotes and one heterozygote. Conclusion: The high prevalence of this variant in individuals from this small community can be explained by a possible founder effect associated with historical, geographical and cultural aspects.

18.
Lasers Med Sci ; 38(1): 90, 2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36947266

RESUMEN

The present study aimed to evaluate photobiomodulation effects on oxidative stress in type 2 diabetes mellitus (DM2). Thirty-one male Wistar rats were used and divided into 4 groups: group 1 - animals without diabetes mellitus 2 without laser 21 J/cm2 (C-SHAM), group 2 - animals with diabetes mellitus 2 without laser 21 J/cm2 (C-DM2), group 3 - animals without diabetes mellitus 2 with laser 21 J/cm2 (L-SHAM), group 4 - animals with diabetes mellitus 2 with laser 21 J/cm2 (L-DM2). The protocol was performed 5 days/week, for 6 weeks. The animals that received photobiomodulation had one dose irradiated at two spots in the right gastrocnemius muscle. Twenty-four hours after the last intervention, the animals were euthanized. Heart, diaphragm, liver, right gastrocnemius, plasma, kidneys, weighed, and stored for further analysis. In rats with DM2, photobiomodulation promoted a decrease in thiobarbituric acid reactive substance assay (TBARS) in plasma levels. On the other hand, photobiomodulation demonstrated an increase in non-protein thiol levels (NPSH) in the heart, diaphragm and gastrocnemius. Moreover, photobiomodulation produced in the heart, diaphragm and plasma levels led to an increase in superoxide dismutase (SOD). Interestingly, photobiomodulation was able to increase superoxide dismutase in rats without DM2 in the heart, diaphragm, gastrocnemius and kidneys. These findings suggested that 6 weeks of photobiomodulation in rats with DM2 promoted beneficial adaptations in oxidative stress, with a decrease in parameters of oxidant activity and an increase in antioxidant activity.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Ratas , Masculino , Animales , Ratas Wistar , Diabetes Mellitus Tipo 2/radioterapia , Diabetes Mellitus Experimental/radioterapia , Estrés Oxidativo , Superóxido Dismutasa/metabolismo , Sustancias Reactivas al Ácido Tiobarbitúrico
19.
BMC Med Educ ; 23(1): 966, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38102605

RESUMEN

BACKGROUND: Congenital Anomalies were responsible for 303,000 deaths in the neonatal period, according to the WHO, they are among the world's top 20 causes of morbidity and mortality. Expensive simulators demonstrate several diseases, but few are related to congenital anomalies. This study aims to develop, validate, and evaluate low-cost simulator models (WALL-GO) of the most common abdominal wall defects, gastroschisis, and omphalocele, to enable diagnosis through an accessible tool with study value and amenable to replication. METHODS: Market research was conducted to find materials to build low-cost models. The researchers built the model and underwent validation assessment of the selected experts who scored five or more in the adapted Fehring criteria. The experts were assessed through a 5-point Likert scale to 7 statements (S1-7). Statements were assigned values according to relevance in face and transfer validities. Concomitantly, the model was also evaluated by students from 1st to 5th year with the same instruments. Content Validity Indexes (CVIs) were considered validated between groups with concordance greater than 90%. Text feedback was also collected. Each statement was subjected to Fisher's Exact Test. RESULTS: Gastroschisis and omphalocele model costs were US $15 and US $27, respectively. In total, there were 105 simulator evaluators. 15 experts were selected. Of the 90 students, there were 16 (1st year), 22 (2nd), 16 (3rd), 22 (4th), and 14 (5th). Students and experts obtained CVI = 96.4% and 94.6%, respectively. The CVIs of each statement were not significantly different between groups (p < 0,05). CONCLUSIONS: The WALL-GO models are suitable for use and replicable at a manufacturable low cost. Mannequins with abdominal wall defects are helpful in learning to diagnose and can be applied in teaching and training health professionals in developing and low-income countries.


Asunto(s)
Pared Abdominal , Educación de Pregrado en Medicina , Gastrosquisis , Hernia Umbilical , Recién Nacido , Humanos , Gastrosquisis/diagnóstico , Hernia Umbilical/cirugía , Hernia Umbilical/diagnóstico , Aprendizaje
20.
Sensors (Basel) ; 23(17)2023 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-37688089

RESUMEN

Enhancing recovery is a fundamental component of high-performance sports training since it enables practitioners to potentiate physical performance and minimise the risk of injuries. Using a new sports legging embedded with an intelligent system for electrostimulation, localised heating and compression (completely embodied into the textile structures), we aimed to analyse acute recovery following a fatigue protocol. Surface electromyography- and torque-related variables were recorded on eight recreational athletes. A fatigue protocol conducted in an isokinetic dynamometer allowed us to examine isometric torque and consequent post-exercise acute recovery after using the sports legging. Regarding peak torque, no differences were found between post-fatigue and post-recovery assessments in any variable; however, pre-fatigue registered a 16% greater peak torque when compared with post-fatigue for localised heating and compression recovery methods. Our data are supported by recent meta-analyses indicating that individual recovery methods, such as localised heating, electrostimulation and compression, are not effective to recover from a fatiguing exercise. In fact, none of the recovery methods available through the sports legging tested was effective in acutely recovering the torque values produced isometrically.


Asunto(s)
Atletas , Rendimiento Atlético , Humanos , Ejercicio Físico , Terapia por Ejercicio , Fatiga
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