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1.
Int J Biol Macromol ; : 134940, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39173806

RESUMEN

The patterns of formation of chitosan nanoparticles doped with vancomycin and coatings based on them in carbonate solutions have been investigated for the first time in this study. Using a technique of radioactive indicators, it was found that at a CO2 pressure of 30 MPa, the yield of the nanoparticles was ~85 %, and a maximum antibiotic encapsulation efficiency of ~30 % was achieved. By spectrophotometric and high-resolution microscopy, it was found that the coating of stabilized xenopericardial tissue of bioprosthetic heart valve, based on chitosan nanoparticles doped with vancomycin with a zeta potential |ζ| ~20 mV completely covers collagen fibers by depositing about 60 nm nanoparticles onto them under direct deposition from carbonic acid at a pressure of 30 MPa CO2. The coating preserves the mechanical strength characteristics of collagen tissue and completely suppresses the growth of S. aureus pathogenic biofilm. This is consistent with the observed increase in antibiotic release of 15 % when the medium was acidified. Histological study demonstrated that the structure of pericardial tissues was not significantly altered by the deposition nanoparticles from carbonic acid. It was found that the rate of biodegradation of polymers and vancomycin in the coating differs by half (16 weeks for the rat model). A significantly lower degradation rate of antibiotics (~50 % of vancomycin total remaining mass and ~25 % of chitosan) was associated with its reliable encapsulation into nanoparticles.

3.
PLOS Glob Public Health ; 4(8): e0002404, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39159182

RESUMEN

Traditional patient- and provider-level hypertension interventions have proven insufficient to halt hypertension as the leading cause of morbidity and mortality globally. Systems-level interventions are required to address factors challenging hypertension control across a social ecological framework, an under-studied topic particularly salient in low- and middle-income countries (LMICs) such as Peru. To inform such interventions, we sought to identify key health systems barriers to hypertension care in Puno, Peru. A participatory stakeholder workshop (October 2021) and 21 in-depth interviews (October 2021-March 2022) were conducted with 55 healthcare professionals (i.e., doctors, nurses, midwives, dentists, nutritionists), followed by a deductive qualitative analysis of transcripts and notes. Participating healthcare providers indicated that low prioritization and lack of national policies for hypertension care have resulted in limited funding and lack of societal-level prevention efforts. Additionally, limited cultural consideration, both in national guidelines as well as by some providers in Puno, results in inadequate care that may not align with local traditions. Providers highlighted that patient care is also hampered by inadequate distribution and occasional shortages of medications and equipment, as well as a lack of personnel and limited opportunities for training in hypertension. Multiple incompatible health information systems, complicated referral systems, and geographic barriers additionally hinder continuity of care and care seeking. Insights gained from health providers on the healthcare system in Puno provide essential contextual information to inform development of organizational-level strategies necessary to improve provider and patient behaviors to achieve better hypertension care outcomes.

4.
IEEE Trans Biomed Eng ; PP2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39106138

RESUMEN

OBJECTIVE: Repetitive atrial activation patterns (RAAPs) during complex atrial tachycardia could be associated with localized mechanisms that can be targeted. Clinically available electroanatomical mapping systems are limited by either the spatial coverage or electrode density of the mapping catheters, preventing the adequate visualization of transiently occurring RAAPs. This work proposes a technique to overcome this shortcoming by stitching spatially overlapping conduction patterns together to a larger image- called a composite map. METHODS: Simulated stable mechanisms and meandering reentries are sequentially mapped (4x4 grid, 3mm spacing) and then reconstructed back to the original sizes with the proposed recurrence plot-based algorithm. RESULTS: The reconstruction of single linear waves presents minimal errors (local activation time (LAT) difference: 3.2 [1.6-4.9] ms, conduction direction difference: 5.2 [2.3-8.0] degrees). Errors significantly increase (p<0.05) for more complex patterns, being the highest with unstable reentries (LAT difference: 10.3 [3.5-16.2] ms, conduction direction difference: 18.2 [6.7-29.7] deg). In a second part of the analysis, 111 meandering reentries are reconstructed. Mapping 30 locations overlappingly around each reentry core was found to be the optimal mapping strategy. For this optimal setting, LAT, conduction direction, and core localization errors are low (6.1 [4.2-8.6] ms, 11.2 [8.6-15.5] deg and 4.1 [2.9-4.9] mm, respectively) and are weakly correlated with the degree of the meander ( ρ=0.41, ρ=0.40 and ρ=0.20, respectively). CONCLUSION: Our findings underline the feasibility of generating composite maps by stitching spatially overlapping recordings. SIGNIFICANCE: Composite maps can be instrumental in personalized ablation strategies.

5.
Inflamm Bowel Dis ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38970379

RESUMEN

Upadacitinib, a selective JAK-1 inhibitor, was used as rescue therapy for ulcerative colitis in the setting of pregnancy following use of mesalamine, vedolizumab, infliximab, and corticosteroids. This resulted in an uncomplicated live full birth without need for surgical intervention.

6.
NAR Genom Bioinform ; 6(3): lqae090, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39071850

RESUMEN

Efficient de novo motif discovery from the results of wide-genome mapping of transcription factor binding sites (ChIP-seq) is dependent on the choice of background nucleotide sequences. The foreground sequences (ChIP-seq peaks) represent not only specific motifs of target transcription factors, but also the motifs overrepresented throughout the genome, such as simple sequence repeats. We performed a massive comparison of the 'synthetic' and 'genomic' approaches to generate background sequences for de novo motif discovery. The 'synthetic' approach shuffled nucleotides in peaks, while in the 'genomic' approach selected sequences from the reference genome randomly or only from gene promoters according to the fraction of A/T nucleotides in each sequence. We compiled the benchmark collections of ChIP-seq datasets for mouse, human and Arabidopsis, and performed de novo motif discovery. We showed that the genomic approach has both more robust detection of the known motifs of target transcription factors and more stringent exclusion of the simple sequence repeats as possible non-specific motifs. The advantage of the genomic approach over the synthetic approach was greater in plants compared to mammals. We developed the AntiNoise web service (https://denovosea.icgbio.ru/antinoise/) that implements a genomic approach to extract genomic background sequences for twelve eukaryotic genomes.

7.
Chemistry ; : e202402791, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39078697

RESUMEN

The incorporation of cationic groups onto electron-poor compounds is a viable strategy for achieving potent electron acceptors, as evidenced by reports of air-stable radical forms of large aromatic diimides such as naphthalene and perylene diimides. These ions have also been observed to exhibit anion-π interaction tendencies of interest in molecular recognition applications. The benefits of phosphonium incorporation, however, have not yet been extended to the smallest benzene diimides. Here, we report that dibrominated pyromellitic diimide and mellophanic diimide both readily undergo substitution reactions with phosphine sources to yield bisphosphonium compounds. In the single crystalline form, these dications display anion-π interactions and, in the case of mellophanic diimide, the stabilization of a bromide-water H-bonding ring pattern. The reaction of these dications with chemical reductants readily provides the singly and doubly reduced redox states, which were characterized by UV-vis spectroscopy and found to exhibit intense absorptions extending into the near-IR region. Taken together, this work demonstrates that phosphonium incorporation onto congested aromatic diimide scaffolds is synthetically viable and produces unusual electron-poor compounds.

8.
Methods Mol Biol ; 2821: 83-89, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38997482

RESUMEN

In the quality control of synthetic peptides, mass spectroscopy (MS) serves as an optimal method for evaluating authenticity and integrity. Typically, the sequence of a synthetic peptide is already established, thereby directing the focus of analysis towards validating its identity and purity. This chapter outlines straightforward methodologies for conducting MS analyses specifically tailored for synthetic peptides.


Asunto(s)
Espectrometría de Masas , Péptidos , Péptidos/química , Péptidos/análisis , Espectrometría de Masas/métodos , Control de Calidad , Secuencia de Aminoácidos , Espectrometría de Masas en Tándem/métodos
9.
Transplantation ; 108(8): 1669-1680, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39012953

RESUMEN

BACKGROUND: Thoracoabdominal normothermic regional perfusion (TA-NRP) has emerged as a powerful technique for optimizing organ procurement from donation after circulatory death donors. Despite its rapid adoption, standardized guidelines for TA-NRP implementation are lacking, prompting the need for consensus recommendations to ensure safe and effective utilization of this technique. METHODS: A working group composed of members from The American Society of Transplant Surgeons, The International Society of Heart and Lung Transplantation, The Society of Thoracic Surgeons, and The American Association for Thoracic Surgery was convened to develop technical guidelines for TA-NRP. The group systematically reviewed existing literature, consensus statements, and expert opinions to identify key areas requiring standardization, including predonation evaluation, intraoperative management, postdonation procedures, and future research directions. RESULTS: The working group formulated recommendations encompassing donor evaluation and selection criteria, premortem testing and therapeutic interventions, communication protocols, and procedural guidelines for TA-NRP implementation. These recommendations aim to facilitate coordination among transplant teams, minimize variability in practice, and promote transparency and accountability throughout the TA-NRP process. CONCLUSIONS: The consensus guidelines presented herein serve as a comprehensive framework for the successful and ethical implementation of TA-NRP programs in organ procurement from donation after circulatory death donors. By providing standardized recommendations and addressing areas of uncertainty, these guidelines aim to enhance the quality, safety, and efficiency of TA-NRP procedures, ultimately contributing to improved outcomes for transplant recipients.


Asunto(s)
Consenso , Preservación de Órganos , Perfusión , Humanos , Perfusión/normas , Perfusión/métodos , Preservación de Órganos/normas , Preservación de Órganos/métodos , Donantes de Tejidos/provisión & distribución , Trasplante de Órganos/normas , Trasplante de Órganos/métodos , Selección de Donante/normas , Obtención de Tejidos y Órganos/normas , Obtención de Tejidos y Órganos/métodos
10.
Ann Thorac Surg ; 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39023462

RESUMEN

BACKGROUND: Thoracoabdominal normothermic regional perfusion (TA-NRP) has emerged as a powerful technique for optimizing organ procurement from donation after circulatory death donors. Despite its rapid adoption, standardized guidelines for TA-NRP implementation are lacking, prompting the need for consensus recommendations to ensure safe and effective utilization of this technique. METHODS: A working group composed of members from The American Society of Transplant Surgeons, The International Society of Heart and Lung Transplantation, The Society of Thoracic Surgeons, and The American Association for Thoracic Surgery was convened to develop technical guidelines for TA-NRP. The group systematically reviewed existing literature, consensus statements, and expert opinions to identify key areas requiring standardization, including predonation evaluation, intraoperative management, postdonation procedures, and future research directions. RESULTS: The working group formulated recommendations encompassing donor evaluation and selection criteria, premortem testing and therapeutic interventions, communication protocols, and procedural guidelines for TA-NRP implementation. These recommendations aim to facilitate coordination among transplant teams, minimize variability in practice, and promote transparency and accountability throughout the TA-NRP process. CONCLUSIONS: The consensus guidelines presented herein serve as a comprehensive framework for the successful and ethical implementation of TA-NRP programs in organ procurement from donation after circulatory death donors. By providing standardized recommendations and addressing areas of uncertainty, these guidelines aim to enhance the quality, safety, and efficiency of TA-NRP procedures, ultimately contributing to improved outcomes for transplant recipients.

11.
Vision Res ; 223: 108458, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39079282

RESUMEN

Glaucoma, the leading cause of irreversible blindness worldwide, is a neurodegenerative disease characterized by chronic axonal damages and progressive loss of retinal ganglion cells, with increased intraocular pressure (IOP) as the primary risk factor. While current treatments focus solely on reducing IOP, understanding glaucoma through experimental models is essential for developing new therapeutic strategies and biomarkers for early diagnosis. Our research group developed an ocular hypertension rat model based on limbal plexus cautery, which provides significant glaucomatous neurodegeneration up to four weeks after injury. We evaluated long-term morphological, functional, and vascular alterations in this model. Our results showed that transient ocular hypertension, lasting approximately one week, can lead to progressive increase in optic nerve cupping and retinal ganglion cells loss. Remarkably, the pressure insult caused several vascular changes, such as arteriolar and venular thinning, and permanent choroidal vascular swelling. This study provides evidence of the longitudinal effects of a pressure insult on retinal structure and function using clinical modalities and techniques. The multifactorial changes reported in this model resemble the complex retinal ganglion cell degeneration found in glaucoma patients, and therefore may also provide a unique tool for the development of novel interventions to either halt or slow down disease progression.

12.
Am J Dermatopathol ; 46(9): e77-e78, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39008502

RESUMEN

ABSTRACT: A 45-year-old woman with a history of previously treated left plantar foot melanoma presented with a left thigh mass. Fine needle aspiration findings were concerning for metastatic melanoma (MM). Imaging was remarkable for PET-avidity of both the biopsied thigh mass and of a left posterior knee nodule. The knee nodule was also enhancing on MRI, concerning for a site of metastasis. Resection of the thigh mass and intra-articular nodule was performed. The thigh lesion was positive for MM. The specimen obtained from the knee demonstrated a proliferation of spindle and epithelioid cells associated with focal fibrosis and scattered giant cells with brown pigment, raising the possibility of melanoma metastasis with treatment effect. Additional immunohistochemical studies with anti-SOX10 failed to demonstrate melanoma cells in the lesion. The final diagnosis for the knee nodule was pigmented villonodular synovitis. This case highlights the potential for pigmented villonodular synovitis to mimic MM, requiring additional pathologic analysis to yield an accurate diagnosis.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Sinovitis Pigmentada Vellonodular , Humanos , Sinovitis Pigmentada Vellonodular/patología , Femenino , Persona de Mediana Edad , Melanoma/secundario , Melanoma/patología , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/secundario , Diagnóstico Diferencial , Inmunohistoquímica , Imagen por Resonancia Magnética
13.
ACS Nano ; 18(28): 18485-18492, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38958189

RESUMEN

Collagen is the most abundant protein in tissue scaffolds in live organisms. Collagen can self-assemble in vitro, which has led to a number of biotechnological and biomedical applications. To understand the dominant factors that participate in the formation of collagen nanostructures, here we study in real time and with nanoscale resolution the disassembly and reassembly of collagens. We implement a high-speed force microscope, which provides in situ high spatiotemporal resolution images of collagen nanostructures under changing pH conditions. The disassembly and reassembly are dominated by the electrostatic interactions among amino-acid residues of different molecules. Acidic conditions favor disassembly by neutralizing negatively charged residues. The process sets a net repulsive force between collagen molecules. A neutral pH favors the presence of negative and positively charged residues along the collagen molecules, which promotes their electrostatic attraction. Molecular dynamics simulations reproduce the experimental behavior and validate the electrostatic-based model of the disassembly and reassembly processes.


Asunto(s)
Colágeno , Simulación de Dinámica Molecular , Nanoestructuras , Electricidad Estática , Colágeno/química , Nanoestructuras/química , Concentración de Iones de Hidrógeno , Microscopía de Fuerza Atómica , Animales
14.
Animals (Basel) ; 14(14)2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39061537

RESUMEN

The objective of the current study was to evaluate the effects of soybean oil inclusion in diets on feeding behaviour, digestibility, performance, and blood metabolites of feedlot lambs. Forty non-castrated Santa Inês lambs with a mean age of 5 months and initial body weight of 34.88 ± 3.19 kg were used in a 40-day feeding trial. The lambs were distributed in five experimental diets with the inclusion of increasing soybean oil (SO) levels: 0, 30, 60, 90, and 120 g/kg DM. The SO inclusion promoted a linear reduction in DM intake (p < 0.001), crude protein (CP, p < 0.001), non-fibrous carbohydrates (NFC, p < 0.001), and total digestible nutrients (TDN, p = 0.004). There was an increasing quadratic effect on the intake of ether extract (EE; p = 0.002) and decreasing for neutral detergent fiber (p = 0.005). The soybean oil inclusion promoted the greater apparent digestibility of CP (p = 0.016), EE (p = 0.005), NDFom (p < 0.001), and TDN (p < 0.001); on the other hand, the apparent digestibility of NFC (p = 0.005) was decreased. The average daily gain decreased (p < 0.001) with SO inclusion. The SO inclusion increased feeding time (p = 0.004), reduced the efficiency of DM rumination (p = 0.001), and reduced the concentration of blood N-ureic (p < 0.001). Considering the productive parameters, SO can be included in diets and it is recommended that we include SO of up to 41 g/kg DM in diets for fattening lambs as the ideal maximum level. The strategy implemented to adapt lambs to increasing levels of high-fat diet mitigated the detrimental effects of lipids on the rumen, with high-density energy intake being the constraining factor on performance.

15.
medRxiv ; 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-39040171

RESUMEN

Background: Prostate cancer (PCa) is among the most common cancers in men and its diagnosis requires the histopathological evaluation of biopsies by human experts. While several recent artificial intelligence-based (AI) approaches have reached human expert-level PCa grading, they often display significantly reduced performance on external datasets. This reduced performance can be caused by variations in sample preparation, for instance the staining protocol, section thickness, or scanner used. Another limiting factor of contemporary AI-based PCa grading is the prediction of ISUP grades, which leads to the perpetuation of human annotation errors. Methods: We developed the prostate cancer aggressiveness index (PCAI), an AI-based PCa detection and grading framework that is trained on objective patient outcome, rather than subjective ISUP grades. We designed PCAI as a clinical application, containing algorithmic modules that offer robustness to data variation, medical interpretability, and a measure of prediction confidence. To train and evaluate PCAI, we generated a multicentric, retrospective, observational trial consisting of six cohorts with 25,591 patients, 83,864 images, and 5 years of median follow-up from 5 different centers and 3 countries. This includes a high-variance dataset of 8,157 patients and 28,236 images with variations in sample thickness, staining protocol, and scanner, allowing for the systematic evaluation and optimization of model robustness to data variation. The performance of PCAI was assessed on three external test cohorts from two countries, comprising 2,255 patients and 9,437 images. Findings: Using our high-variance datasets, we show how differences in sample processing, particularly slide thickness and staining time, significantly reduce the performance of AI-based PCa grading by up to 6.2 percentage points in the concordance index (C-index). We show how a select set of algorithmic improvements, including domain adversarial training, conferred robustness to data variation, interpretability, and a measure of credibility to PCAI. These changes lead to significant prediction improvement across two biopsy cohorts and one TMA cohort, systematically exceeding expert ISUP grading in C-index and AUROC by up to 22 percentage points. Interpretation: Data variation poses serious risks for AI-based histopathological PCa grading, even when models are trained on large datasets. Algorithmic improvements for model robustness, interpretability, credibility, and training on high-variance data as well as outcome-based severity prediction gives rise to robust models with above ISUP-level PCa grading performance.

16.
Implement Sci Commun ; 5(1): 62, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38845055

RESUMEN

As global adoption of antiretroviral therapy extends the lifespan of People Living with HIV (PLHIV) through viral suppression, the risk of comorbid conditions such as hypertension has risen, creating a need for effective, scalable interventions to manage comorbidities in PLHIV. The Heart, Lung, and Blood Co-morbiditieS Implementation Models in People Living with HIV (HLB-SIMPLe) Alliance has been funded by the National Heart, Lung, and Blood Institute (NHLBI) and the Fogarty International Center (FIC) since September 2020. The Alliance was created to conduct late-stage implementation research to contextualize, implement, and evaluate evidence-based strategies to integrate the diagnosis, treatment, and control of cardiovascular diseases, particularly hypertension, in PLHIV in low- and middle-income countries (LMICs).The Alliance consists of six individually-funded clinical trial cooperative agreement research projects based in Botswana, Mozambique, Nigeria, South Africa, Uganda, and Zambia; the Research Coordinating Center; and personnel from NIH, NHLBI, and FIC (the Federal Team). The Federal Team works together with the members of the seven cooperative agreements which comprise the alliance. The Federal Team includes program officials, project scientists, grant management officials and clinical trial specialists. This Alliance of research scientists, trainees, and administrators works collaboratively to provide and support venues for ongoing information sharing within and across the clinical trials, training and capacity building in research methods, publications, data harmonization, and community engagement. The goal is to leverage shared learning to achieve collective success, where the resulting science and training are greater with an Alliance structure rather than what would be expected from isolated and unconnected individual research projects.In this manuscript, we describe how the Research Coordinating Center performs the role of providing organizational efficiencies, scientific technical assistance, research capacity building, operational coordination, and leadership to support research and training activities in this multi-project cooperative research Alliance. We outline challenges and opportunities during the initial phases of coordinating research and training in the HLB-SIMPLe Alliance, including those most relevant to dissemination and implementation researchers.

17.
Artículo en Inglés | MEDLINE | ID: mdl-38859788

RESUMEN

BACKGROUND: Neurotrophins are essential factors for neural growth and function; they play a crucial role in neurodegenerative diseases where their expression levels are altered. Our previous research has demonstrated changes in synaptic plasticity and neurotrophin expression levels in a pharmacological model of Huntington's disease induced by 3-nitropropionic acid (3-NP). In the 3- NP-induced HD model, corticostriatal Long Term Depression (LTD) was impaired, but neurotrophin-3 (NT-3) restored striatal LTD. This study delves into the NT-3-induced signaling pathways involved in modulating and restoring striatal synaptic plasticity in cerebral slices from 3-NPinduced striatal degeneration in mice in vivo. METHODS: Phospholipase C (PLC), phosphatidylinositol-3-kinase (PI3K), and mitogen-activated protein kinase (MEK)/extracellular signal-regulated kinase (ERK) pathways activated by NT-3 were analyzed by means of field electrophysiological recordings in brain slices from control and 3-NP treated in the presence of specific inhibitors of the signaling pathways. RESULTS: Using specific inhibitors, PLC, PI3K, and MEK/ERK signaling pathways contribute to NT3-mediated plasticity modulation in striatal tissue slices recorded from control animals. However, in the neurodegeneration model induced by 3-NP, the recovery of striatal LTD induced by NT-3 was prevented only by the PLC inhibitor. Moreover, the PLC signaling pathway appeared to trigger downstream activation of the endocannabinoid system, evidenced by AM 251, an inhibitor of the CB1 receptor, also hindered NT-3 plasticity recovery. CONCLUSION: Our finding highlights the specific involvement of the PLC pathway in the neuroprotective effects of NT-3 in mitigating synaptic dysfunction under neurodegenerative conditions.

18.
Am J Dermatopathol ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38941542

RESUMEN

ABSTRACT: Spitz melanocytic neoplasms exhibit frequent chromosomal rearrangements leading to recurring gene fusions, such as ALK fusions. TPM3 and DCTN1 emerge as the predominant fusion partners of ALK, although less common partners such as NPM1, TPR, CLIP1, GTF3C2, MLPH, EEF2, MYO5A, and KANK1 have also been documented. Although ALK fusions are primarily associated with Spitz nevi or atypical Spitz tumors, instances of Spitz melanoma with ALK fusions documented in the English literature are exceedingly rare. Here, we present a case of Spitz melanoma harboring SLC20A1::ALK fusion, highlighting a novel fusion transcript not previously reported in Spitz melanocytic neoplasms, including Spitz melanomas. In addition, the tumor exhibits multiple aberrant chromosomal alterations characteristic of melanoma, along with a somatic mutation in GRM3.

19.
Am Heart J ; 275: 192-199, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38944263

RESUMEN

BACKGROUND: Hypertensive disorders of pregnancy (HDP) are associated with increased long-term risk for cardiometabolic risk factors (chronic hypertension [HTN], obesity, diabetes) and heart failure. Exercise capacity is a known predictor of heart failure in patients with normal resting cardiac filling pressures. In this prospective observational cohort study, we sought to identify predictors of reduced postpartum exercise capacity in participants with normotensive vs preeclamptic pregnancies. METHODS: Preeclampsia (PreE) and normotensive subjects were enrolled to undergo bedside echocardiography within 48 hours of delivery, and rest/exercise echocardiography 12 weeks postpartum. RESULTS: Recruited subjects (n = 68) were grouped according to their blood pressure as: a) normotensive pregnancy n = 15; b) PreE with normotensive postpartum (PreE-Resolved, n = 36); c) PreE with persistent postpartum HTN (PreE-HTN, n = 17). At enrollment, a significantly higher percentage of subjects in the PreE-HTN group were Black. Compared to normotensive and PreE-Resolved subjects, those with PreE-HTN demonstrated higher resting systolic blood pressure (SBP, 112 [normotensive] vs 112 [PreE-Resolved] vs 134 [PreE-HTN], P < .001) and diastolic blood pressure (DBP, 70.0 vs 72.5 vs 85.0, P < .001), and significantly less postpartum weight loss (9.6% vs 13.6% vs 3.8%, P < .001). Following Bruce protocol stress testing, PreE-HTN subjects demonstrated achieved significantly lower exercise duration (10.4 vs 10.2 vs 7.9 minutes, P = .001). Subjects with PreE-HTN also demonstrated evidence of exercise-induced diastolic dysfunction as assessed by peak exercise lateral e' (18.0 vs 18.0 vs 13.5, P = .045) and peak exercise tricuspid regurgitation velocity (TR Vm, 2.4 vs 3.0 vs 3.1, P = 0.045). Exercise duration was negatively associated with gravidity (R = -0.27, P = .029) and postpartum LV mass index (R = -0.45, P < .001), resting average E/e' (R = -0.51, P < .001), BMI (R = -0.6, P < .001) and resting SBP (R = -0.51, P < .001). CONCLUSIONS: Postpartum exercise stress testing capacity is related to readily available clinical markers including pregnancy factors, echocardiographic parameters and unresolved cardiometabolic risk factors.


Asunto(s)
Tolerancia al Ejercicio , Periodo Posparto , Preeclampsia , Humanos , Femenino , Embarazo , Adulto , Preeclampsia/fisiopatología , Preeclampsia/diagnóstico , Preeclampsia/epidemiología , Estudios Prospectivos , Tolerancia al Ejercicio/fisiología , Ecocardiografía/métodos , Prueba de Esfuerzo/métodos , Presión Sanguínea/fisiología
20.
J Am Chem Soc ; 146(19): 12889-12894, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38690854

RESUMEN

We have successfully achieved selective and efficient functionalization of sheet edges in microcrystalline multilayer γ-graphyne through two methods: cross-coupling with residual bromide edge groups and copper-catalyzed azide-alkyne cycloaddition (CuAAC) with edge terminal alkyne groups. This modification significantly enhances the ease of mechanical exfoliation and dispersibility of the sheets of γ-graphyne. Specifically, C18-grafted γ-graphyne forms stable dispersions in compatible organic solvents, allowing for the imaging of atomically thin layers of γ-graphyne for the first time. Additionally, we have discovered that phenylacetylide edge groups alter the preferred stacking mode of γ-graphyne sheets. Few-layer flakes of Ph-edge γ-graphyne exhibit a preference for the R3m space group, contrasting with the aperiodic stacking of Br-edge γ-graphyne. These results open the door for scalable exfoliation of few-layer flakes of γ-graphyne with a high aspect ratio, enabling potential applications in carbon electronics.

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