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1.
Beilstein J Org Chem ; 20: 1527-1547, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39015617

RESUMO

The selective fluorination of C(sp3)-H bonds is an attractive target, particularly for pharmaceutical and agrochemical applications. Consequently, over recent years much attention has been focused on C(sp3)-H fluorination, and several methods that are selective for benzylic C-H bonds have been reported. These protocols operate via several distinct mechanistic pathways and involve a variety of fluorine sources with distinct reactivity profiles. This review aims to give context to these transformations and strategies, highlighting the different tactics to achieve fluorination of benzylic C-H bonds.

2.
Heart Rhythm ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39019386

RESUMO

BACKGROUND: The subcutaneous implantable cardioverter-defibrillator (S-ICD) has emerged as an alternative to transvenous systems for preventing sudden cardiac death. However, concerns have been raised regarding its efficacy and safety in obese individuals. OBJECTIVE: This meta-analysis aims to evaluate the efficacy and safety of the S-ICD in patients with obesity by assessing the relationship between body mass index (BMI) and clinical outcomes. METHODS: A comprehensive search of multiple databases was conducted for English-language peer-reviewed studies reporting clinical outcomes in S-ICD recipients with (BMI ≥30 kg/m2) and without obesity (BMI <30 kg/m2). Data on pre-implantation screening failure, defibrillation testing, complications, appropriate and inappropriate shocks, and survival were analysed using standard random-effect meta-analytical techniques. RESULTS: Twenty-nine studies involving 20,486 patients were included. There was no statistically significant difference in the mean BMI values of patients with failed or successful preimplantation screening (mean difference -0.60 kg/m2, 95% CI -2.06 to 0.86). Obesity was associated with higher rates of failed defibrillation testing at ≤65J (OR 2.16, 95% CI 1.39-3.35), and mal-/suboptimal positioning occurred more frequently in obese compared to non-obese patients (OR 3.37, 95% CI 1.76-6.44). Increased BMI as a continuous variable (per increase in 1 kg/m2 BMI) was associated with elevated defibrillation thresholds (OR 1.05, 95% CI 1.03-1.08), a higher risk of complications (HR 1.04, 95% CI 1.02-1.05), a trend towards increased number of appropriate shocks (HR 1.02, 95% CI 1.00-1.04), and no significant increase in the risk for inappropriate shocks (HR 1.01, 95% CI 0.99-1.03). CONCLUSION: This meta-analysis underscores the importance of considering obesity in S-ICD implantation decisions. While S-ICD remains effective in obese patients, attention to potential technical challenges and higher complication rates is warranted.

3.
J Am Coll Cardiol ; 84(4): 354-364, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39019530

RESUMO

BACKGROUND: ARTESiA (Apixaban for the Reduction of Thrombo-Embolism in Patients With Device-Detected Sub-Clinical Atrial Fibrillation) demonstrated that apixaban, compared with aspirin, significantly reduced stroke and systemic embolism (SE) but increased major bleeding in patients with subclinical atrial fibrillation. OBJECTIVES: To help inform decision making, the authors evaluated the efficacy and safety of apixaban according to baseline CHA2DS2-VASc score. METHODS: We performed a subgroup analysis according to baseline CHA2DS2-VASc score and assessed both the relative and absolute differences in stroke/SE and major bleeding. RESULTS: Baseline CHA2DS2-VASc scores were <4 in 1,578 (39.4%) patients, 4 in 1,349 (33.6%), and >4 in 1,085 (27.0%). For patients with CHA2DS2-VASc >4, the rate of stroke was 0.98%/year with apixaban and 2.25%/year with aspirin; compared with aspirin, apixaban prevented 1.28 (95% CI: 0.43-2.12) strokes/SE per 100 patient-years and caused 0.68 (95% CI: -0.23 to 1.57) major bleeds. For CHA2DS2-VASc <4, the stroke/SE rate was 0.85%/year with apixaban and 0.97%/year with aspirin. Apixaban prevented 0.12 (95% CI: -0.38 to 0.62) strokes/SE per 100 patient-years and caused 0.33 (95% CI: -0.27 to 0.92) major bleeds. For patients with CHA2DS2-VASc =4, apixaban prevented 0.32 (95% CI: -0.16 to 0.79) strokes/SE per 100 patient-years and caused 0.28 (95% CI: -0.30 to 0.86) major bleeds. CONCLUSIONS: One in 4 patients in ARTESiA with subclinical atrial fibrillation had a CHA2DS2-VASc score >4 and a stroke/SE risk of 2.2% per year. For these patients, the benefits of treatment with apixaban in preventing stroke/SE are greater than the risks. The opposite is true for patients with CHA2DS2-VASc score <4. A substantial intermediate group (CHA2DS2-VASc =4) exists in which patient preferences will inform treatment decisions. (Apixaban for the Reduction of Thrombo-Embolism in Patients With Device-Detected Sub-Clinical Atrial Fibrillation; NCT01938248).


Assuntos
Aspirina , Fibrilação Atrial , Inibidores do Fator Xa , Pirazóis , Piridonas , Acidente Vascular Cerebral , Humanos , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/complicações , Pirazóis/uso terapêutico , Piridonas/uso terapêutico , Piridonas/efeitos adversos , Piridonas/administração & dosagem , Aspirina/uso terapêutico , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/epidemiologia , Inibidores do Fator Xa/uso terapêutico , Medição de Risco/métodos , Hemorragia/induzido quimicamente , Hemorragia/epidemiologia
4.
J Chem Inf Model ; 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39002142

RESUMO

Ribonucleic acid (RNA) molecules can adopt a variety of secondary and tertiary structures in solution, with stem-loops being one of the more common motifs. Here, we present a systematic analysis of 15 RNA stem-loop sequences simulated with molecular dynamics simulations in an implicit solvent environment. Analysis of RNA cluster ensembles showed that the stem-loop structures can generally adopt the A-form RNA in the stem region. Loop structures are more sensitive, and experimental structures could only be reproduced with modification of CH···O interactions in the force field, combined with an implicit solvent nonpolar correction to better model base stacking interactions. Accurately modeling RNA with current atomistic physics-based models remains challenging, but the RNA systems studied herein may provide a useful benchmark set for testing other RNA modeling methods in the future.

5.
JAMA Netw Open ; 7(7): e2421589, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38990569

RESUMO

Importance: Numerous prospective cohort studies have reported a J-shaped association of urinary sodium excretion with cardiovascular events and mortality. Objective: To study the association between sodium intake and incident atrial fibrillation (AF). Design, Setting, and Participants: This cohort study included participants in the Ongoing Telmisartan Alone and in Combination with Ramipril Global Endpoint Trial (ONTARGET) and Telmisartan Randomised Assessment Study in ACE Intolerant Subjects With Cardiovascular Disease (TRANSCEND) multicenter, randomized clinical trials comparing the effect of ramipril 10 mg daily with telmisartan 80 mg daily, or their combination (ONTARGET) or 80 mg telmisartan daily with placebo (TRANSCEND) for the outcome of death from cardiovascular causes, myocardial infarction, stroke, or hospitalization for heart failure. ONTARGET and TRANSCEND included 31 546 participants with vascular disease or high-risk diabetes, and this study excluded participants without a urine sample for sodium measurement, missing data for key covariates, a history of AF, or AF detected in the first year after enrollment. Analyses were performed in July 2023 to May 2024. Exposure: Estimated sodium intake from a morning fasting urine sample (Kawasaki formula). Main Outcomes and Measures: The main outcome was incident AF. The association between estimated sodium intake and incident AF was modeled using multivariable adjusted Cox regression and cubic splines. Results: A total of 27 391 participants (mean [SD] age, 66.3 [7.2] years; 19 310 [70.5%] male) were included. Mean (SD) estimated sodium intake was 4.8 (1.6) g/d. During a mean (SD) follow-up of 4.6 (1.0) years, 1562 participants (5.7%) had incident AF. After multivariable adjustment, a J-shaped association between sodium intake and AF risk was observed (P for nonlinearity = .03). Sodium intake of 8 g/d or greater (3% of participants) was associated with incident AF (hazard ratio, 1.32; 95% CI, 1.01-1.74) compared with sodium intake of 4 to 5.99 g/d. Cubic splines showed that sodium intake greater than 6 g/d (19% of participants) was associated with a 10% increased AF risk per additional 1-g/d sodium intake (hazard ratio, 1.10; 95% CI, 1.03-1.18), but with no further lowering of AF risk at lower levels of sodium intake. Conclusions and Relevance: In this cohort study of sodium intake and AF risk, there was a J-shaped association between sodium intakes and AF risk in patients with cardiovascular disease or diabetes. Lowering sodium intake for AF prevention is best targeted at individuals who consume high sodium diets.


Assuntos
Fibrilação Atrial , Humanos , Fibrilação Atrial/epidemiologia , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Doenças Vasculares/epidemiologia , Incidência , Sódio na Dieta/efeitos adversos , Sódio na Dieta/administração & dosagem , Estudos de Coortes , Estudos Prospectivos
6.
Heart Rhythm ; 21(5S): S467-S468, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38971581

RESUMO

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/policies/article-withdrawal). This abstract has been retracted at the request of the Authors; please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). The abstract was withdrawn after being accepted for presentation at Heart Rhythm, the annual meeting of the Heart Rhythm Society, because there was substantial content development after it had been submitted, both in terms of more in-depth analyses and quantitative changes due to final adjudication of events. The Authors intended to withdraw the abstract from publication as well but omitted to do so. The Authors apologize for the inconvenience caused by this oversight.


Assuntos
Inteligência Artificial , Telemetria , Humanos , Telemetria/métodos , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatologia , Frequência Cardíaca/fisiologia
9.
J Agric Food Chem ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39028868

RESUMO

Previous clinical studies indicate that monoamine oxidase-B (MAO-B) inhibition by blackcurrants must be predominantly attributed to bioactives other than anthocyanins. In this natural products discovery study, MAO-A/B inhibitory phytochemicals were isolated from blackcurrants, and a double-blind crossover study investigated the efficacy of freeze-dried whole-fruit blackcurrant powder in inhibiting MAO-B compared with blackcurrant juice in healthy adults. Platelet MAO-B inhibition was comparable between powder (89% ± 6) and juice (91% ± 4), and it was positively correlated with MAO-modulated plasma catecholamines, subjective alertness, and reduced mental fatigue, assessed using the Bond-Lader questionnaire. Sarmentosin, a nitrile glycoside, and its hydroxycinnamoyl esters were identified as novel MAO-A/B inhibitors from blackcurrant in vitro, and sarmentosin was demonstrated to inhibit platelet MAO-B activity in vivo. These findings confirm sarmentosin as the primary bioactive for MAO-A/B inhibition in blackcurrants, as well as its bioavailability and stability during freeze-drying, and suggest that consuming blackcurrant powder and juice may positively affect mood in healthy adults.

10.
Urol Oncol ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39013714

RESUMO

BACKGROUND: The rise in advanced prostate cancer has coincided with increased use of Magnetic Resonance Imaging (MRI), leading to the hypothesis that this increase in surveillance registries is an artifact of more sensitive imaging tools. We assessed the association between regional variation in prostate MRI and advanced prostate cancer diagnoses. METHODS: We utilized SEER-Medicare data (2004-2015), including men > 65 diagnosed with localized prostate cancer. The predictor variable was the utilization of prostate MRI in each hospital referral region (HRR, representing regional healthcare markets). We compared the proportion of disease recorded as locally advanced or of regional risk group (cT3, cT4, and cN1) which would plausibly have been detected by prostate MRI. We conducted adjusted multivariable analysis and performed correlation analysis with Spearman rank coefficient at the level of the HRR. Sensitivity analysis for years 2011 to 2015 was conducted. RESULTS: Of 98,921 men diagnosed, 4.01% had locally advanced or regional disease. The median prostate MRI utilization rate was 4.58% (IQR [3.03%, 8.12%]). Adjusted multivariable analysis revealed no statistically significant correlation between MRI utilization and proportion of advanced prostate cancer (aOR = 1.01, 95% CI, [0.99,1.03]) in each region. The correlation between MRI usage and advanced diagnosis was not significant (Spearman Ρ = 0.09, P = 0.4). Sensitivity analysis conducted between 2011 and 2015 showed similar results (aOR = 1.008, 95% CI, [0.989, 1.027]; Spearman Ρ = 0.16, P = 0.1). CONCLUSIONS: During our study period, HRR-level utilization of MRI was not associated with higher incidences of advanced prostate cancer. This suggests the rising advanced prostate cancer diagnoses observed in this period are unlikely an artifact of greater sensitivity of modern imaging tests, but potentially due to other factors such as changes in screening or risk factors. With increased utilization and evolving techniques in recent years, the association between MRI and advanced prostate cancer detection warrants continued monitoring.

11.
Circ Res ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38957990

RESUMO

BACKGROUND: PANX1 (pannexin 1), a ubiquitously expressed ATP release membrane channel, has been shown to play a role in inflammation, blood pressure regulation, and myocardial infarction. However, the possible role of PANX1 in cardiomyocytes in the progression of heart failure has not yet been investigated. METHOD: We generated a novel mouse line with constitutive deletion of PANX1 in cardiomyocytes (Panx1MyHC6). RESULTS: PANX1 deletion in cardiomyocytes had no effect on unstressed heart function but increased the glycolytic metabolism and resulting glycolytic ATP production, with a concurrent decrease in oxidative phosphorylation, both in vivo and in vitro. In vitro, treatment of H9c2 cardiomyocytes with isoproterenol led to PANX1-dependent release of ATP and Yo-Pro-1 uptake, as assessed by pharmacological blockade with spironolactone and siRNA-mediated knockdown of PANX1. To investigate nonischemic heart failure and the preceding cardiac hypertrophy, we administered isoproterenol, and we demonstrated that Panx1MyHC6 mice were protected from systolic and diastolic left ventricle volume increases as a result of cardiomyocyte hypertrophy. Moreover, we found that Panx1MyHC6 mice showed decreased isoproterenol-induced recruitment of immune cells (CD45+), particularly neutrophils (CD11b+, Ly6g+), to the myocardium. CONCLUSIONS: Together, these data demonstrate that PANX1 deficiency in cardiomyocytes increases glycolytic metabolism and protects against cardiac hypertrophy in nonischemic heart failure at least in part by reducing immune cell recruitment. Our study implies PANX1 channel inhibition as a therapeutic approach to ameliorate cardiac dysfunction in patients with heart failure.

12.
Artigo em Inglês | MEDLINE | ID: mdl-39034625

RESUMO

BACKGROUND: This Intensive Care Medicine Rapid Practice Guideline (ICM-RPG) provides an evidence-based recommendation to address the question: in adult patients in intensive care units (ICUs), should we use small-volume or conventional blood collection tubes? METHODS: We included 23 panelists in 8 countries and assessed and managed financial and intellectual conflicts of interest. Methodological support was provided by the Guidelines in Intensive Care, Development, and Evaluation (GUIDE) group. We conducted a systematic review, including evidence from observational and randomized studies. Using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach, we evaluated the certainty of evidence and developed recommendations using the Evidence-to-Decision framework. RESULTS: We identified 8 studies (1 cluster and 2 patient-level randomized trials; 5 observational studies) comparing small-volume to conventional tubes. We had high certainty evidence that small-volume tubes reduce daily and cumulative blood sampling volume; and moderate certainty evidence that they reduce the risk of transfusion and mean number of red blood cell units transfused, but these estimates were limited by imprecision. We had high certainty that small-volume tubes have a similar rate of specimens with insufficient quantity. The panel considered that the desirable effects of small-volume tubes outweigh the undesirable effects, are less wasteful of resources, and are feasible, as demonstrated by successful implementation across multiple countries, although there are upfront implementation costs to validate small-volume tubes on laboratory instrumentation. CONCLUSION: This ICM-RPG panel made a strong recommendation for the use of small-volume sample collection tubes in adult ICUs based on overall moderate certainty evidence.

13.
Dalton Trans ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39041822

RESUMO

The speciation and mobility of rare earth elements (REE) strongly depends on pH, which controls the formation of charged aqueous hydroxyl species. The latter potentially play an important role in controlling heavy REE adsorption on clay minerals in near-neutral to alkaline waters such as in regolith-hosted REE mineral deposits. However, accurate REE hydrolysis constants are needed for developing geochemical models that can predict the role of these charged species in natural systems. Here, we develop a robust experimental UV-Vis spectrophotometric method using m-cresol purple to determine in situ pH from 25 to 75 °C. This method is used to derive the average ligand number and hydrolysis constants of erbium (Er) at 25 °C in aqueous solutions with low ionic strength (≤0.001 mol L-1) at pH from ∼7 to 9.5 and in the presence of Er concentrations from 0 to 0.057 mM. The average ligand number ranges between 1 and 3 indicating that Er(OH)2+, Er(OH)2+ and Er(OH)03 control speciation in the experiments. The logarithm of the Er hydrolysis constants (, n = 1 to 3) derived at infinite dilution for the reaction Er3+ + nH2O = Er(OH)n3-n + nH+ are: , , . Implementation of these experimental data into a geochemical model indicates that the Er(OH)2+ and Er(OH)03 species are both stable in a much wider pH range than previously predicted. Consequently, the positively charged REE hydroxyl complexes can potentially control the fractionation of light vs. heavy REE via adsorption as observed in the formation of certain regolith-hosted REE deposits.

14.
Commun Biol ; 7(1): 799, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956304

RESUMO

In this paper, we propose a fluorescence-lifetime imaging microscopy (FLIM) multiplexing system based on the fluorogen-activating protein FAST. This genetically encoded fluorescent labeling platform employs FAST mutants that activate the same fluorogen but provide different fluorescence lifetimes for each specific protein-dye pair. All the proposed probes with varying lifetimes possess nearly identical and the smallest-in-class size, along with quite similar steady-state optical properties. In live mammalian cells, we target these chemogenetic tags to two intracellular structures simultaneously, where their fluorescence signals are clearly distinguished by FLIM. Due to the unique structure of certain fluorogens under study, their complexes with FAST mutants display a monophasic fluorescence decay, which may facilitate enhanced multiplexing efficiency by reducing signal cross-talks and providing optimal prerequisites for signal separation upon co-localized and/or spatially overlapped labeling.


Assuntos
Corantes Fluorescentes , Microscopia de Fluorescência , Microscopia de Fluorescência/métodos , Corantes Fluorescentes/química , Humanos , Animais , Fluorescência , Mutação
15.
medRxiv ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38947017

RESUMO

Impulsivity can be a risk factor for serious complications for those with mood disorders. To understand intra-individual impulsivity variability, we analyzed longitudinal data of a novel gamified digital Go/No-Go (GNG) task in a clinical sample (n=43 mood disorder participants, n=17 healthy controls) and an open-science sample (n=121, self-reported diagnoses). With repeated measurements within-subject, we disentangled two aspects of GNG: reaction time and accuracy in response inhibition (i.e., incorrect No-Go trials) with respect to diurnal and potential learning effects. Mixed-effects models showed diurnal effects in reaction time but not accuracy, with a significant effect of hour on reaction time in the clinical sample and the open-science sample. Moreover, subjects improved on their response inhibition but not reaction time. Additionally, significant interactions emerged between depression symptom severity and time-of-day in both samples, supporting that repeated administration of our GNG task can yield mood-dependent circadian rhythm-aware biomarkers of neurocognitive function.

16.
Hum Reprod ; 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38970902

RESUMO

STUDY QUESTION: What is the longitudinal association between gestational phthalate exposure and in vivo placental outcomes? SUMMARY ANSWER: Phthalates were adversely associated with placental microvasculature, stiffness, and presence of calcification, with different metabolites associated with different outcomes. WHAT IS KNOWN ALREADY: Phthalate exposure is ubiquitous and implicated as a contributor to adverse pregnancy outcomes, possibly through impacts on the placenta. STUDY DESIGN, SIZE, DURATION: A total of 303 women were recruited in early pregnancy and prospectively followed for up to eight visits across gestation in the Human Placenta and Phthalates study. PARTICIPANTS/MATERIALS, SETTING, METHODS: At each visit, women provided urine samples and underwent placental ultrasounds. Urine was analyzed for 18 metabolites of phthalates and replacements. We took the geometric mean of repeated measurements to reflect pregnancy-averaged phthalate or replacement exposure for each participant (n = 303). Placental microvasculature, stiffness, and microcalcification presence were quantified from ultrasounds at each visit. Higher scores reflected worse placental function for all measures. Generalized linear mixed models were created to estimate the association between pregnancy-averaged exposure biomarker concentrations and repeated outcome measurements for microvasculature and stiffness. Gestational age at the time of calcification detection was modeled using Cox proportional hazards models. MAIN RESULTS AND THE ROLE OF CHANCE: Monocarboxyisononyl phthalate and summed di(2-ethylhexyl) phthalate metabolites were associated with impaired microvasculature development, such that an interquartile range increase in concentration was associated with 0.11 standard deviation increase in the microvasculature ratio, indicating poorer vascularization (95% CI: 0.00, 0.22); 0.11 [95% CI: -0.01, 0.22], respectively. Monoethyl phthalate was associated with increased placental stiffness (0.09 [95% CI: -0.01, 0.19]) while summed di-iso-butyl phthalate metabolites and monobenzyl phthalate were associated with increased hazard of calcification detection (hazard ratios: 1.18 [95% CI: 0.98, 1.42]; 1.13 [95% CI: 0.96, 1.34]). LIMITATIONS, REASONS FOR CAUTION: Outcomes used in this study are novel and further investigation is needed to provide clinical context and relevance. WIDER IMPLICATIONS OF THE FINDINGS: We found evidence of associations between select phthalate biomarkers and various aspects of in vivo placental health, although we did not observe consistency across placental outcomes. These findings could illustrate heterogeneous effects of phthalate exposure on placental function. STUDY FUNDING/COMPETING INTEREST(S): This research was supported in part by the Intramural Research Program of the NIH, National Institute of Environmental Health Sciences (ZIA ES103344), and NIEHS T32ES007018. The authors declare that they have no competing interests to disclose. The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention. Use of trade names is for identification only and does not imply endorsement by the CDC, the Public Health Service, or the US Department of Health and Human Services. TRIAL REGISTRATION NUMBER: N/A.

17.
BMC Neurol ; 24(1): 235, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38969967

RESUMO

BACKGROUND: Mild traumatic brain injury (mTBI) can result in lasting brain damage that is often too subtle to detect by qualitative visual inspection on conventional MR imaging. Although a number of FDA-cleared MR neuroimaging tools have demonstrated changes associated with mTBI, they are still under-utilized in clinical practice. METHODS: We investigated a group of 65 individuals with predominantly mTBI (60 mTBI, 48 due to motor-vehicle collision, mean age 47 ± 13 years, 27 men and 38 women) with MR neuroimaging performed in a median of 37 months post-injury. We evaluated abnormalities in brain volumetry including analysis of left-right asymmetry by quantitative volumetric analysis, cerebral perfusion by pseudo-continuous arterial spin labeling (PCASL), white matter microstructure by diffusion tensor imaging (DTI), and neurometabolites via magnetic resonance spectroscopy (MRS). RESULTS: All participants demonstrated atrophy in at least one lobar structure or increased lateral ventricular volume. The globus pallidi and cerebellar grey matter were most likely to demonstrate atrophy and asymmetry. Perfusion imaging revealed significant reductions of cerebral blood flow in both occipital and right frontoparietal regions. Diffusion abnormalities were relatively less common though a subset analysis of participants with higher resolution DTI demonstrated additional abnormalities. All participants showed abnormal levels on at least one brain metabolite, most commonly in choline and N-acetylaspartate. CONCLUSION: We demonstrate the presence of coup-contrecoup perfusion injury patterns, widespread atrophy, regional brain volume asymmetry, and metabolic aberrations as sensitive markers of chronic mTBI sequelae. Our findings expand the historic focus on quantitative imaging of mTBI with DTI by highlighting the complementary importance of volumetry, arterial spin labeling perfusion and magnetic resonance spectroscopy neurometabolite analyses in the evaluation of chronic mTBI.


Assuntos
Neuroimagem , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Neuroimagem/métodos , Imageamento por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/metabolismo , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Lesões Encefálicas Traumáticas/metabolismo , Lesões Encefálicas Traumáticas/patologia , Atrofia/patologia , Circulação Cerebrovascular/fisiologia , Espectroscopia de Ressonância Magnética/métodos
18.
Dalton Trans ; 53(29): 12215-12222, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38973664

RESUMO

Three NaBa12(BO3)7F4 crystals were grown in the BaO-BaF2-B2O3-Na2O system from three different compositions of high-temperature solution. With the use of optical spectroscopy, energy-dispersive X-ray spectroscopy, and the Schering bridge method it was found that the crystals revealed sharp differences in their optical and dielectric properties. The relative permittivity of the crystals in direction perpendicular to the optical axis reached 319(5). The minimum deviation technique was used for refractive index measurements.

19.
Int J Mol Sci ; 25(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-39000162

RESUMO

Cell-based therapies using corneal stromal stem cells (CSSC), corneal keratocytes, or a combination of both suppress corneal scarring. The number of quiescent keratocytes in the cornea is small; it is difficult to expand them in vitro in quantities suitable for transplantation. This study examined the therapeutic effect of corneal fibroblasts reversed into keratocytes (rCF) in a mouse model of mechanical corneal injury. The therapeutic effect of rCF was studied in vivo (slit lamp, optical coherence tomography) and ex vivo (transmission electron microscopy and immunofluorescence staining). Injection of rCF into the injured cornea was accompanied by recovery of corneal thickness, improvement of corneal transparency, reduction of type III collagen in the stroma, absence of myofibroblasts, and the improvement in the structural organization of collagen fibers. TEM results showed that 2 months after intrastromal injection of cells, there was a decrease in the fibril density and an increase in the fibril diameter and the average distance between collagen fibrils. The fibrils were well ordered and maintained the short-range order and the number of nearest-neighbor fibrils, although the averaged distance between them increased. Our results demonstrated that the cell therapy of rCF from ReLEx SMILe lenticules promotes the recovery of transparent corneal stroma after injury.


Assuntos
Lesões da Córnea , Fibroblastos , Animais , Camundongos , Lesões da Córnea/terapia , Lesões da Córnea/patologia , Fibroblastos/metabolismo , Córnea , Ceratócitos da Córnea , Modelos Animais de Doenças , Terapia Baseada em Transplante de Células e Tecidos/métodos , Substância Própria , Tomografia de Coerência Óptica
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