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1.
CJC Open ; 6(3): 582-596, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38559335

RESUMO

Background: To facilitate the shift from risk-factor management to primordial prevention of cardiovascular disease, the American Heart Association developed guidelines to score and track cardiovascular health (CVH). How the prevalence and trajectories of a high level of CVH across the life course compare among high- and lower-income countries is unknown. Methods: Nationally representative survey data with CVH variables (physical activity, cigarette smoking, body mass index, blood pressure, blood glucose, and total cholesterol levels) were identified in Ethiopia, Bangladesh, Brazil, England, and the US for adults (aged 18-69 years and not pregnant). Data were harmonized, and CVH metrics were scored using the American Heart Association guidelines, as high (2), moderate (1), or low (0), with the prevalence of high scores (better CVH) across the life course compared across countries. Results: Among 28,092 adults (Ethiopia n = 7686, 55.2% male; Bangladesh n = 6731, 48.4% male; Brazil n = 7241, 47.9% male; England n = 2691, 49.5% male, and the US n = 3743, 50.3% male), the prevalence of high CVH scores decreased as country income level increased. Declining CVH with age was universal across countries, but differences were already observable in those aged 18 years. Excess body weight appeared to be the main driver of poor CVH in higher-income countries, and the prevalence of current smoking was highest in Bangladesh. Conclusions: Our findings suggest that CVH decline with age may be universal. Interventions to promote and preserve CVH throughout the life course are needed in all populations, tailored to country-specific time courses of the decline. In countries where the level of CVH remains relatively high, protection of whole societies from risk-factor epidemics may still be feasible.


Contexte: Afin de faciliter la transition de la prise en charge des facteurs de risque vers la prévention primordiale des maladies cardiovasculaires, l'American Heart Association a élaboré des lignes directrices en vue de mesurer la santé cardiovasculaire (SCV) et d'en faire le suivi. On ignore dans quelle mesure la prévalence et la trajectoire d'un niveau élevé de SCV au cours d'une vie se comparent entre les pays à revenu élevé et les pays à plus faible revenu. Méthodologie: Des résultats de sondages représentatifs des pays concernant les variables de la SCV (activité physique, tabagisme, indice de masse corporelle, pression artérielle, glycémie et taux de cholestérol total) ont été obtenus de l'Éthiopie, du Bangladesh, du Brésil, de l'Angleterre et des États-Unis, pour des adultes âgés de 18 à 69 ans, excluant les femmes enceintes. Les données ont été harmonisées, et la SCV a été mesurée conformément aux lignes directrices de l'American Heart Association, et notée en fonction des scores suivants : élevée (2), modérée (1) ou faible (0). La prévalence de scores élevés, soit une meilleure SCV tout au long de la vie, a été comparée entre les pays. Résultats: Parmi 28 092 adultes (Éthiopie, n = 7 686, 55,2 % de sexe masculin; Bangladesh, n = 6 731, 48,4 % de sexe masculin; Brésil, n = 7 241, 47,9 % de sexe masculin; Angleterre, n = 2 691, 49,5 % de sexe masculin, et États-Unis, n = 3 743, 50,3 % de sexe masculin), la prévalence de scores correspondant à une SCV élevée diminuait à mesure que le niveau de revenu du pays augmentait. La diminution de la SCV avec l'âge était universelle dans tous les pays, mais des différences étaient déjà observables chez les personnes âgées de 18 ans. Un surplus de poids corporel semblait être le principal facteur d'une faible SCV dans les pays à revenu plus élevé; la prévalence d'un tabagisme actuel était la plus élevée au Bangladesh. Conclusions: Nos observations laissent croire que le déclin de la SCV avec l'âge pourrait être universel. Il est nécessaire de mener des interventions adaptées à la progression du déclin dans chacun des pays en vue de favoriser et de préserver la SCV tout au long de la vie, et ce, dans toutes les populations. Dans les pays où le niveau de SCV demeure relativement élevé, il pourrait être encore possible de protéger des sociétés entières contre des épidémies liées aux facteurs de risque.

2.
Indian Heart J ; 76 Suppl 1: S121-S129, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38599726

RESUMO

This review article describes the pathophysiological mechanisms linking Apolipoprotein B (Apo-B) and atherosclerosis, summarizes the existing evidence on Apo B as a predictor of atherosclerotic cardiovascular disease and recommendations of (inter)national treatment guidelines regarding Apo B in dyslipidemia management. A single Apo B molecule is present in every particle of very low-density lipoprotein, intermediate density lipoprotein, low density lipoprotein, and lipoprotein(a). This unique single Apo B per particle ratio makes plasma Apo B concentration a direct measure of the number of circulating atherogenic lipoproteins. This review of global evidence on Apo B as a biomarker for atherosclerosis confirms that Apo B is a single atherogenic lipid marker present in all lipids sub-fractions except HDL-C, and thus, Apo B integrates and extends the information from triglycerides and cholesterol, which could simplify and improve care for atherosclerotic cardiovascular disease.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Humanos , Doenças Cardiovasculares/diagnóstico , Aterosclerose/diagnóstico , Triglicerídeos , Apolipoproteínas B , Biomarcadores , Lipoproteína(a) , HDL-Colesterol , Apolipoproteína A-I
3.
Res Sq ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38585722

RESUMO

Background: Postnatal care is recommended as a means of preventing maternal mortality during the postpartum period, but many women in low- and middle-income countries (LMICs) do not access care during this period. We set out to examine sociocultural preferences that have been portrayed as barriers to care. Methods: We performed an abductive analysis of 63 semi-structured interviews with women who had recently given birth in three regions of Ethiopia using the Health Equity Implementation Framework (HEIF) and an inductive-deductive codebook to understand why women in Ethiopia do not use recommended postnatal care. Results: We found that, in many cases, health providers do not consider women's cultural safety a primary need, but rather as a barrier to care. However, women's perceived refusal to participate in postnatal visits was, for many, an expression of agency and asserting their needs for cultural safety. Trial registration: n/a. Conclusions: We propose adding cultural safety to HEIF as a process outcome, so that implementers consider cultural needs in a dynamic manner that does not ask patients to choose between meeting their cultural needs and receiving necessary health care during the postnatal period.

4.
Glob Heart ; 19(1): 34, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638124

RESUMO

Background: COVID-19 cardiovascular research from Africa is limited. This study describes cardiovascular risk factors, manifestations, and outcomes of patients hospitalised with COVID-19 in the African region, with an overarching goal to investigate whether important differences exist between African and other populations, which may inform health policies. Methods: A multinational prospective cohort study was conducted on adults hospitalised with confirmed COVID-19, consecutively admitted to 40 hospitals across 23 countries, 6 of which were African countries. Of the 5,313 participants enrolled globally, 948 were from African sites (n = 9). Data on demographics, pre-existing conditions, clinical outcomes in hospital (major adverse cardiovascular events (MACE), renal failure, neurological events, pulmonary outcomes, and death), 30-day vitality status and re-hospitalization were assessed, comparing African to non-African participants. Results: Access to specialist care at African sites was significantly lower than the global average (71% vs. 95%), as were ICU admissions (19.4% vs. 34.0%) and COVID-19 vaccination rates (0.6% vs. 7.4%). The African cohort was slightly younger than the non-African cohort (55.0 vs. 57.5 years), with higher rates of hypertension (48.8% vs. 46.9%), HIV (5.9% vs. 0.3%), and Tuberculosis (3.6% vs. 0.3%). In African sites, a higher proportion of patients suffered cardiac arrest (7.5% vs. 5.1%) and acute kidney injury (12.7% vs. 7.2%), with acute kidney injury (AKI) appearing to be one of the strongest predictors of MACE and death in African populations compared to other populations. The overall mortality rate was significantly higher among African participants (18.2% vs. 14.2%). Conclusions: Overall, hospitalised African patients with COVID-19 had a higher mortality despite a lower mean age, contradicting literature that had previously reported a lower mortality attributed to COVID-19 in Africa. African sites had lower COVID-19 vaccination rates and higher AKI rates, which were positively associated with increased mortality. In conclusion, African patients were hospitalized with more severe COVID-19 cases and had poorer outcomes.


Assuntos
Injúria Renal Aguda , COVID-19 , Adulto , Humanos , COVID-19/epidemiologia , COVID-19/complicações , Estudos Prospectivos , Vacinas contra COVID-19 , Injúria Renal Aguda/epidemiologia , África/epidemiologia , Fatores de Risco , Estudos Retrospectivos
5.
Aging Cell ; : e14166, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38659245

RESUMO

Gray matter (GM) alterations play a role in aging-related disorders like Alzheimer's disease and related dementias, yet MRI studies mainly focus on macroscopic changes. Although reliable indicators of atrophy, morphological metrics like cortical thickness lack the sensitivity to detect early changes preceding visible atrophy. Our study aimed at exploring the potential of diffusion MRI in unveiling sensitive markers of cortical and subcortical age-related microstructural changes and assessing their associations with cognitive and behavioral deficits. We leveraged the Human Connectome Project-Aging cohort that included 707 participants (394 female; median age = 58, range = 36-90 years) and applied the powerful mean apparent diffusion propagator model to measure microstructural parameters, along with comprehensive behavioral and cognitive test scores. Both macro- and microstructural GM characteristics were strongly associated with age, with widespread significant microstructural correlations reflective of cellular morphological changes, reduced cellular density, increased extracellular volume, and increased membrane permeability. Importantly, when correlating MRI and cognitive test scores, our findings revealed no link between macrostructural volumetric changes and neurobehavioral performance. However, we found that cellular and extracellular alterations in cortical and subcortical GM regions were associated with neurobehavioral performance. Based on these findings, it is hypothesized that increased microstructural heterogeneity and decreased neurite orientation dispersion precede macrostructural changes, and that they play an important role in subsequent cognitive decline. These alterations are suggested to be early markers of neurocognitive performance that may distinctly aid in identifying the mechanisms underlying phenotypic aging and subsequent age-related functional decline.

6.
Environ Res ; 252(Pt 1): 118786, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38537743

RESUMO

Industrial wastewater contains a wide range of pollutants that, if released directly into natural ecosystems, have the potential to pose serious risks to the environment.This study aims to investigate sustainable and efficient approaches for treating tannery wastewater, employing a combination of hyphenated Fenton oxidation and adsorption processes. Rigorous analyses were conducted on wastewater samples, evaluating parameters like COD, sulphide, NH3-N, PO43-, NO3-, and Cr(VI). The performance of this adsorbent material was gauged through column adsorption experiments. A comprehensive characterization of the adsorbent was undertaken using techniques such as SEM, EDX, BET, FTIR, XRD, and LIBS. The study delved into varying operational parameters like bed depth (ranging from 3.5 to 9.5 cm) diameter (2.5 cm) and influent flow rate (ranging from 5 to 15mLmin-1). The experimental outcomes revealed that increasing the bed depth and decreasing the influent flow rate significantly bolstered the adsorption column's effectiveness. Breakthrough curves obtained were fitted with different models, including the Thomas and Yoon-Nelson models. The most optimal column performance was achieved with a bed height of 10.5 cm and a flow rate of 5mLmin-1. The combined process achieved removal efficiencies of 94.5% for COD, 97.4% for sulphide, 96.2% for NH3-N, 83.1% for NO3-, 79.3% for PO43-, and 96.9% for Cr(VI) in tannery effluent. This research presents a notable stride toward the development of sustainable and efficient strategies for tannery wastewater treatment.

7.
J Investig Med ; : 10815589241236156, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38378444

RESUMO

High-quality training and networking are pivotal for enhancing the research capacity of early- to mid-career researchers in the prevention and control of non-communicable diseases. Beyond building research skills, these professionals gain valuable insights from interdisciplinary mentorship, networking opportunities, and exposure to diverse cultures and health systems. Despite the significance of such initiatives, their implementation remains underexplored. Here, we describe the implementation and evaluation of the Excellence in Non-COommunicable disease REsearch (ENCORE) program, a collaborative initiative between Australia and India that was launched in 2016 and spanned a duration of 3 years. Led by a consortium that included the University of Melbourne and leading Indian research and medical institutions, ENCORE involved 15 faculty members and 20 early-mid career researchers. The program comprised various elements, including face-to-face forums, masterclasses, webinars, a health-technology conference, and roundtable events. ENCORE successfully trained the early-career researchers, resulting in over 30 peer-reviewed articles, 36 conference presentations, and the submission of seven grant applications, three of which received funding. Beyond individual achievements, ENCORE fostered robust research collaboration between Australian and Indian institutions, showcasing its broader impact on strengthening research capacities across borders.

8.
Brain Struct Funct ; 229(4): 853-863, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38381381

RESUMO

Blunt and diffuse injury is a highly prevalent form of traumatic brain injury (TBI) which can result in microstructural alterations in the brain. The blunt impact on the brain can affect the immediate contact region but can also affect the vulnerable regions like hippocampus, leading to functional impairment and long-lasting cognitive deficits. The hippocampus of the moderate weight drop injured male rats was longitudinally assessed for microstructural changes using in vivo MR imaging from 4 h to Day 30 post-injury (PI). The DTI analysis found a prominent decline in the apparent diffusion coefficient (ADC), radial diffusivity (RD), and axial diffusivity (AD) values after injury. The perturbed DTI scalars accompanied histological changes in the hippocampus, wherein both the microglia and astrocytes showed changes in the morphometric parameters at all timepoints. Along with this, the hippocampus showed presence of Aß positive fibrils and neurite plaques after injury. Therefore, this study concludes that TBI can lead to a complex morphological, cellular, and structural alteration in the hippocampus which can be diagnosed using in vivo MR imaging techniques to prevent long-term functional deficits.


Assuntos
Lesões Encefálicas Traumáticas , Imagem de Tensor de Difusão , Ratos , Masculino , Animais , Imagem de Tensor de Difusão/métodos , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Encéfalo/patologia , Imagem de Difusão por Ressonância Magnética , Hipocampo/patologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-38311294

RESUMO

Birds have the highest blood glucose among vertebrates. Several mechanisms may explain this including the lack of a functional insulin-responsive glucose transport protein, high glucagon concentrations, and reliance on lipid oxidation resulting in the production of gluconeogenic precursors. The hypothesis was that interruption of gluconeogenesis using the diabetes medication metformin would lower glucose concentrations in wild-caught birds. We captured two cohorts of adult mourning doves, Zenaida macroura, and acclimated them to captivity for two weeks. In this crossover study, cohort 1 was administered a single dose of one of the following oral treatments each week: metformin (150 or 300 mg/kg), glycogenolysis inhibitor (2.5 mg/kg 1,4-dideoxy-1,4-imino-D-arabinitol (DAB)), or water (50 µL). Whole blood glucose was measured using a glucometer at baseline, 30, 60, and 120 min following the oral doses. In contrast to mammals and chickens, 300 mg/kg metformin did not alter blood glucose (p > 0.05) whereas 150 mg/kg metformin increased blood glucose compared to water (p = 0.043). To examine whether 150 mg/kg metformin stimulated glycogenolysis, we co-administered 150 mg/kg metformin and 2.5 mg/kg DAB, which prevented the hyperglycemic response. Cohort 2 was administered the same treatments and the early response was examined (0, 5, 10, 15 min). Low-dose metformin increased blood glucose within 5 min (p = 0.039) whereas the high dose had no effect. DAB did not prevent the early response to metformin nor did it alter blood glucose concentrations when administered alone (p = 0.887). In conclusion, metformin increases endogenous blood glucose via glycogenolysis in healthy adult male mourning doves.


Assuntos
Hiperglicemia , Metformina , Humanos , Masculino , Animais , Columbidae , Glicemia , Metformina/farmacologia , Estudos Cross-Over , Galinhas , Hiperglicemia/induzido quimicamente , Animais Selvagens , Água , Pesar , Mamíferos
10.
AAPS PharmSciTech ; 25(1): 13, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191947

RESUMO

Cytotoxicity, speedy degradation, and limited cellular absorption are the foremost features influencing the successful delivery of RNAs. Chitosan (Cs) is a polymer that offers an advantage due to its bio-compatibility and biodegradable nature, making it an ideal polycationic vector for delivering siRNA. In this study, chitosan has been modified with arginine in order to increase its encapsulation of siRNA and improve cellular absorption. It was discovered that arginine and guanidino moieties could transport through membranes of cells and play an important part in membrane permeability. FTIR and 13C NMR were used to characterize the complex. These chitosan-arginine (CsAr) siRNA complexes are further encapsulated in anionic DPPC/cholesterol liposomes to combine the effects of liposome-chitosan-arginine complexes called lipopolyplexes (LCAr). Formed LCAr were investigated for their lipid/CsAr-siRNA ratios, size, zeta-potential, heparin, and serum RNase stability by agarose gel retardation, and cell uptake efficiency compared to their "parent" polyplexes. Results revealed complete lipidation of CsAr-siRNA polyplexes at lipid mass ratio 10 resulting in lipopolyplexes in the 120 to 230nm range. Polyplex entrapped ~70% of siRNA, whereas lipidation increases siRNA encapsulation to ~95%. Developed LCAr showed ~4 times less hemolytic potential as compared to the parent polyplexes at the highest siRNA dose. The CsAr-siRNA and its lipid-coated form showed enhanced cellular association as compared to the marketed Lipofectamine 2000 proving its effectiveness in siRNA delivery. CsAr-liposome conjugation is simple and safe, and serves as a robust carrier for gene transport in physiological situations without compromising transfection efficacy.


Assuntos
Quitosana , RNA Interferente Pequeno , Lipossomos , Arginina , Lipídeos
11.
bioRxiv ; 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38260525

RESUMO

Gray matter (GM) alterations play a role in aging-related disorders like Alzheimer's disease and related dementias, yet MRI studies mainly focus on macroscopic changes. Although reliable indicators of atrophy, morphological metrics like cortical thickness lack the sensitivity to detect early changes preceding visible atrophy. Our study aimed at exploring the potential of diffusion MRI in unveiling sensitive markers of cortical and subcortical age-related microstructural changes and assessing their associations with cognitive and behavioral deficits. We leveraged the Human Connectome Project-Aging cohort that included 707 unimpaired participants (394 female; median age = 58, range = 36-90 years) and applied the powerful mean apparent diffusion propagator model to measure microstructural parameters, along with comprehensive behavioral and cognitive test scores. Both macro- and microstructural GM characteristics were strongly associated with age, with widespread significant microstructural correlations reflective of cellular morphological changes, reduced cellular density, increased extracellular volume, and increased membrane permeability. Importantly, when correlating MRI and cognitive test scores, our findings revealed no link between macrostructural volumetric changes and neurobehavioral performance. However, we found that cellular and extracellular alterations in cortical and subcortical GM regions were associated with neurobehavioral performance. Based on these findings, it is hypothesized that increased microstructural heterogeneity and decreased neurite orientation dispersion precede macrostructural changes, and that they play an important role in subsequent cognitive decline. These alterations are suggested to be early markers of neurocognitive performance that may distinctly aid in identifying the mechanisms underlying phenotypic aging and subsequent age-related functional decline.

12.
Geroscience ; 46(1): 367-394, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37875652

RESUMO

Young blood plasma is known to confer beneficial effects on various organs in mice and rats. However, it was not known whether plasma from young adult pigs rejuvenates old rat tissues at the epigenetic level; whether it alters the epigenetic clock, which is a highly accurate molecular biomarker of aging. To address this question, we developed and validated six different epigenetic clocks for rat tissues that are based on DNA methylation values derived from n = 613 tissue samples. As indicated by their respective names, the rat pan-tissue clock can be applied to DNA methylation profiles from all rat tissues, while the rat brain, liver, and blood clocks apply to the corresponding tissue types. We also developed two epigenetic clocks that apply to both human and rat tissues by adding n = 1366 human tissue samples to the training data. We employed these six rat clocks to investigate the rejuvenation effects of a porcine plasma fraction treatment in different rat tissues. The treatment more than halved the epigenetic ages of blood, heart, and liver tissue. A less pronounced, but statistically significant, rejuvenation effect could be observed in the hypothalamus. The treatment was accompanied by progressive improvement in the function of these organs as ascertained through numerous biochemical/physiological biomarkers, behavioral responses encompassing cognitive functions. An immunoglobulin G (IgG) N-glycosylation pattern shift from pro- to anti-inflammatory also indicated reversal of glycan aging. Overall, this study demonstrates that a young porcine plasma-derived treatment markedly reverses aging in rats according to epigenetic clocks, IgG glycans, and other biomarkers of aging.


Assuntos
Envelhecimento , Epigênese Genética , Humanos , Ratos , Camundongos , Animais , Suínos , Envelhecimento/fisiologia , Biomarcadores , Plasma , Imunoglobulina G
13.
J Trace Elem Med Biol ; 81: 127321, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37918276

RESUMO

INTRODUCTION: Cisplatin, an anti-cancer drug is used to treat a wide range of solid tumors. Nevertheless, nephrotoxicity is the major adverse effect that restricts its clinical application. The present study focuses on the effect of chelidonic acid in cisplatin-induced nephrotoxicity. METHODS: Wistar rats were injected with cisplatin (5 mg/kg, intraperitoneally (i.p.), once in a week for 4 weeks) and chelidonic acid (10, 20, and 40 mg/kg, per oral (p.o.) for 4 weeks). Body weight, urine, biochemical, and oxidative stress parameters were performed to evaluate the effect of chelidonic acid in cisplatin-induced nephrotoxicity in rats. Pro-inflammatory cytokines and nuclear factor erythroid 2-related factor 2 (Nrf2) concentrations were determined. Expression of phospho-AMP activated protein kinase (phospho-AMP) and hypoxia-inducible factor 1-alpha (HIF-1α) was studied with western blot. Haematoxylin and eosin, periodic acid-Schiff, and Masson's trichrome staining were used to study kidney tissues. RESULTS: Relative kidney weight and urine output were significantly increased in cisplatin-administered rats. Whereas, albumin, and creatinine concentration were decreased, and treatment with chelidonic acid reverses these deleterious effects of cisplatin significantly. Kidney functions were improved by chelidonic acid treatment with a reduction in tumor necrosis factor-alpha (TNF-α), Interleukin-6 (IL-6), and transforming growth factor-beta (TGF-ß1) concentration. The oxidative stress was decreased as compared to the cisplatin group. Furthermore, Nrf2 was significantly increased by chelidonic acid treatment. Chelidonic acid treatment significantly increased the expression of phospho-AMPK and HIF-1α in kidney tissue. Histopathological studies revealed that chelidonic acid reduced kidney damage. CONCLUSION: The findings showed that chelidonic acid increases phospho-AMPK and HIF-1α in the kidney tissue and significantly lowers the inflammatory cytokines, thus it is an effective molecule for providing protection against cisplatin-induced nephrotoxicity.


Assuntos
Cisplatino , Rim , Ratos , Animais , Cisplatino/farmacologia , Ratos Wistar , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Quinases Ativadas por AMP/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Citocinas/metabolismo , Estresse Oxidativo
14.
Res Sq ; 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38076888

RESUMO

The brainstem is a fundamental component of the central nervous system yet it is typically excluded from in vivo human brain mapping efforts, precluding a complete understanding of how the brainstem influences cortical function. Here we use high-resolution 7 Tesla fMRI to derive a functional connectome encompassing cortex as well as 58 brainstem nuclei spanning the midbrain, pons and medulla. We identify a compact set of integrative hubs in the brainstem with widespread connectivity with cerebral cortex. Patterns of connectivity between brainstem and cerebral cortex manifest as multiple emergent phenomena including neurophysiological oscillatory rhythms, patterns of cognitive functional specialization, and the unimodal-transmodal functional hierarchy. This persistent alignment between cortical functional topographies and brainstem nuclei is shaped by the spatial arrangement of multiple neurotransmitter receptors and transporters. We replicate all findings using 3 Tesla data from the same participants. Collectively, we find that multiple organizational features of cortical activity can be traced back to the brainstem.

16.
PLOS Glob Public Health ; 3(12): e0002598, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38100392

RESUMO

Dengue is the most rapidly emerging mosquito-borne infection and, due to climate change and unplanned urbanization, it is predicted that the global burden of dengue will rise further as the infection spreads to new geographical locations. Dengue-endemic countries are often unable to cope with such increases, with health care facilities becoming overwhelmed during each dengue season. Furthermore, although dengue has been predominantly a childhood illness in the past, it currently mostly affects adults in many countries, with higher incidence of severe disease and mortality rates in pregnant women and in those with comorbidities. As there is currently no specific treatment for dengue and no early biomarker to identify those who will progress to develop vascular leakage, all individuals with dengue are closely monitored in case they need fluid management. Furthermore, diagnosing patients with acute dengue is challenging due to the similarity of clinical symptoms during early illness and poor sensitivity and specificity of point-of-care diagnostic tests. Novel vector control methods, such as the release of Wolbachia-infected mosquitoes, have shown promising results by reducing vector density and dengue incidence in clinical trial settings. A new dengue vaccine, TAK-003, had an efficacy of 61.2% against virologically confirmed dengue, 84.1% efficacy against hospitalizations and a 70% efficacy against development of dengue haemorrhagic fever (DHF) at 54 months. While vaccines and mosquito control methods are welcome, they alone are unlikely to fully reduce the burden of dengue, and a treatment for dengue is therefore essential. Several novel antiviral drugs are currently being evaluated along with drugs that inhibit host mediators, such as mast cell products. Although viral proteins such as NS1 contribute to the vascular leak observed in severe dengue, the host immune response to the viral infection also plays a significant role in progression to severe disease. There is an urgent need to discover safe and effective treatments for dengue to prevent disease progression.

17.
bioRxiv ; 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37961347

RESUMO

The brainstem is a fundamental component of the central nervous system yet it is typically excluded from in vivo human brain mapping efforts, precluding a complete understanding of how the brainstem influences cortical function. Here we use high-resolution 7 Tesla fMRI to derive a functional connectome encompassing cortex as well as 58 brainstem nuclei spanning the midbrain, pons and medulla. We identify a compact set of integrative hubs in the brainstem with widespread connectivity with cerebral cortex. Patterns of connectivity between brainstem and cerebral cortex manifest as multiple emergent phenomena including neurophysiological oscillatory rhythms, patterns of cognitive functional specialization, and the unimodal-transmodal functional hierarchy. This persistent alignment between cortical functional topographies and brainstem nuclei is shaped by the spatial arrangement of multiple neurotransmitter receptors and transporters. We replicate all findings using 3 Tesla data from the same participants. Collectively, we find that multiple organizational features of cortical activity can be traced back to the brainstem.

18.
Chem Biodivers ; 20(12): e202301241, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37983725

RESUMO

Chelidonic acid is a phytoconstituent found in rhizomes of the perennial plant celandine. The current study aims to evaluate the acute and repeated dose oral toxicity study of chelidonic acid as per the OECD guidelines 425 and 407. The pharmacokinetic and toxicity profile of chelidonic acid was predicted using online servers and tools. A single dose of chelidonic acid (2000 mg/kg) was administered to female Wistar rats in an acute toxicity study, and the animals were monitored for 14 days. We studied the toxicity profile of chelidonic acid at 10, 20, and 40 mg/kg doses in Wistar rats for repeated dose toxicity (28 days). Clinical biochemistry, haematological, and urine parameters were estimated. A gross necropsy and histopathology were performed. A single oral dose of chelidonic acid (2000 mg/kg) showed no signs of toxicity or mortality. The Administration of chelidonic acid showed no significant alterations in haematological, biochemical, and urine parameters. The histopathology showed normal structure and architecture in all the vital organs. A gross necropsy of vital organs showed no signs of toxicity. The chelidonic acid was found to be safe at all selected dose levels in the acute and repeated dose toxicity study in rats.


Assuntos
Extratos Vegetais , Piranos , Ratos , Animais , Ratos Wistar , Piranos/farmacologia , Administração Oral
19.
Carbohydr Res ; 534: 108975, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37871479

RESUMO

Carbohydrates are a basic structural component that are indispensable to all cellular processes. In addition to being employed as chiral starting materials in the synthesis of a variety of natural products, carbohydrates are recognized as naturally occurring molecules having an enormous variety of functional, stereochemical, and structural properties. The understanding and biological roles of carbohydrate derived molecules can be greatly improved by selectively synthesizing functional carbohydrates through incorporating them with privileged scaffolds. For a deeper understanding of their roles and the development of functional materials based on sugar, it is crucial to develop new techniques for efficiently synthesizing, functionalizing, and modifying carbohydrates. Glycohybrids have a wide range of structural and functional characteristics along with protein-carbohydrate interactions that are crucial to mammalian biology and a number of disease states. This review, consisting the literature from January 2017 to July 2023 and provide an overview of recent developments in the chemical synthesis of glycohybrids based on natural product scaffolds of coumarin, quinolone, naphthalene diimide, indole, isatin, naphthoquinone, imidazole and pyrimidine. The biological activity of active glycohybrids are discussed in this review.


Assuntos
Produtos Biológicos , Quinolonas , Animais , Produtos Biológicos/química , Carboidratos/química , Mamíferos
20.
Mol Biotechnol ; 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37856012

RESUMO

VEGF-A or vascular endothelial growth factor-A is an important factor in enabling neovascularization and angiogenesis. VEGF-A is regulated transcriptionally as well as post transcriptionally. Human antigen R (HuR) belonging to the embryonic lethal abnormal vision (ELAV) family is a key regulator promoting stabilization of VEGF-A mRNA. In this research we investigate, whether HuR targeted RNA interference would enable the reduction of the VEGF-A protein in human retinal pigment epithelial cells (ARPE-19) in-vitro, in normoxic conditions. Three siRNA molecules with sequences complementary to three regions of the HuR mRNA were designed. The three designed siRNA molecules were individually transfected in ARPE-19 cells using Lipofectamine™2000 reagent. Post-transfection (24 h, 48 h, 72 h), downregulation of HuR mRNA was estimated by real-time polymerase reaction, while HuR protein and VEGF-A protein levels were semi-quantitatively determined by western blotting techniques. VEGF-A protein levels were additionally quantified using ELISA techniques. All experiments were done in triplicate. The designed siRNA could successfully downregulate HuR mRNA with concomitant decreases in HuR and VEGF-A protein. The study reveals that HuR downregulation can prominently downregulate VEGF-A, making the protein a target for therapy against pathological angiogenesis conditions such as diabetic retinopathy.

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