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1.
Small ; : e2405335, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39286993

RESUMO

It is generally assumed that contact angle hysteresis of superhydrophobic surfaces scales with liquid-solid contact fraction, however, its experimental verification has been problematic due to the limited accuracy of contact angle and sliding angle goniometry. Advances in cantilever-based friction probes enable accurate droplet friction measurements down to the nanonewton regime, thus suiting much better for characterizing the wetting of superhydrophobic surfaces than contact angle hysteresis measurements. This work quantifies the relationship between droplet friction and liquid-solid contact fraction, through theory and experimental validation. Well-defined micropillar and microcone structures are used as model surfaces to provide a wide range of different liquid-solid contact fractions. Micropillars are known to be able to hold the water on top of them, and a theoretical analysis together with confocal laser scanning microscopy shows that despite the spiky nature of the microcones droplets do not sink into the conical structure either, rendering a diminishingly small liquid-solid contact fraction. Droplet friction characterization with a micropipette force sensor technique reveals a strong dependence of the droplet friction on the contact fraction, and the dependency is described with a simple physical equation, despite the nearly three-orders-of-magnitude difference in liquid-solid contact fraction between the sparsest cone surface and the densest pillar surface.

2.
J Am Heart Assoc ; 13(18): e035587, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39268670

RESUMO

BACKGROUND: Paravalvular regurgitation (PVR) is a common complication after transcatheter aortic valve replacement, posing an increased risk of heart failure and mortality. Accurate intraprocedural quantification of PVR is challenging. Both hemodynamic indices and videodensitometry can be used for intraprocedural assessment of PVR. We compared the predictive value of the isolated versus combined use of the hemodynamic index diastolic delta (DD) and videodensitometry for the incidence of relevant PVR 1 month after transcatheter aortic valve replacement. METHODS AND RESULTS: In this prospective cohort study, patients underwent periprocedural PVR assessment by DD and videodensitometry (using left ventricular outflow tract-aortic regurgitation [LVOT-AR]). Cardiac magnetic resonance served as reference modality for PVR assessment. Relevant PVR was defined as cardiac magnetic resonance-regurgitant fraction >20%. Fifty-one patients were enrolled in this study. Mean age was 80.6±5.2 years and 45.1% of patients were men. Mean LVOT-AR and cardiac magnetic resonance-regurgitant fraction were 8.2%±7.8% and 11.7%±9.6%, respectively. The correlation between DD and LVOT-AR was weak (r=-0.36). DD and LVOT-AR showed a comparable accuracy to predict relevant PVR (area under the curve 0.82, 95% CI: 0.69-0.95 versus area area under the time-density curve 0.80, 95% CI: 0.62-0.99). The combination of DD and LVOT-AR improved the prediction of relevant PVR (area under the time-density curve, 0.90, 95% CI: 0.81-0.99), and resulted in an increased concordance (86.3%) and positive predictive value (75%) compared with DD alone (76.5% and 40%, respectively), or LVOT-AR alone (82.3% and 50%, respectively). CONCLUSIONS: DD and videodensitometry are both accurate and feasible modalities for the assessment of PVR after transcatheter aortic valve replacement. The synergistic use of both techniques increases the predictive value for relevant PVR after transcatheter aortic valve replacement. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04281771.


Assuntos
Insuficiência da Valva Aórtica , Valor Preditivo dos Testes , Substituição da Valva Aórtica Transcateter , Humanos , Masculino , Feminino , Insuficiência da Valva Aórtica/etiologia , Insuficiência da Valva Aórtica/fisiopatologia , Insuficiência da Valva Aórtica/diagnóstico , Insuficiência da Valva Aórtica/diagnóstico por imagem , Substituição da Valva Aórtica Transcateter/efeitos adversos , Estudos Prospectivos , Idoso de 80 Anos ou mais , Idoso , Estenose da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/fisiopatologia , Valva Aórtica/cirurgia , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/fisiopatologia , Hemodinâmica/fisiologia , Diástole , Resultado do Tratamento , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/diagnóstico
3.
Int J Pharm ; 665: 124694, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39265855

RESUMO

Cryopreservation is important in manufacturing of cell therapy products, influencing their safety and effectiveness. During freezing and thawing, intracellular events such as dehydration and ice formation can impact cell viability. In this study, the impact of controlling the ice nucleation temperature on intracellular events and viability were investigated. A model T cell line, Jurkat cells, were evaluated in commercially relevant cryoformulations (2.5 and 5 % v/v DMSO in Plasma-Lyte A) using a cryomicroscopic setup to monitor the dynamic changes cells go through during freeze-thaw as well as a controlled rate freezer to study bulk freeze-thaw. The equilibrium freezing temperatures of the studied formulations and a DMSO/Plasma-Lyte A liquidus curve were determined using DSC. The cryomicroscopic studies revealed that an ice nucleation temperature of -6°C, close to the equilibrium freezing temperatures of cryoformulations, led to more intracellular dehydration and less intracellular ice formation during freezing compared to either a lower ice nucleation temperature (-10 °C) or uncontrolled ice nucleation. The cell membrane integrity and post thaw viability in bulk cryopreservation consistently demonstrated the advantage of the higher ice nucleation temperature, and the correlation between the cellular events and cell viability.

5.
Eur Heart J ; 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39185705

RESUMO

BACKGROUND AND AIMS: To explore male-female differences in aneurysm growth and clinical outcomes in a two-centre retrospective Dutch cohort study of adult patients with ascending aortic aneurysm (AscAA). METHODS: Adult patients in whom imaging of an AscAA (root and/or ascending: ≥40 mm) was performed between 2007 and 2022 were included. Aneurysm growth was analysed using repeated measurements at the sinuses of Valsalva (SoV) and tubular ascending aorta. Male-female differences were explored in presentation, aneurysm characteristics, treatment strategy, survival, and clinical outcomes. RESULTS: One thousand eight hundred and fifty-eight patients were included (31.6% female). Median age at diagnosis was 65.4 years (interquartile range: 53.4-71.7) for females and 59.0 years (interquartile range: 49.3-68.0) for males (P < .001). At diagnosis, females more often had tubular ascending aortic involvement (75.5% vs. 70.2%; P = .030) while males more often had SoV involvement (42.8% vs. 21.6%; P < .001). Maximum absolute aortic diameter, at any location, at diagnosis did not differ between females (45.0 mm) and males (46.5 mm; P = .388). In females, tubular ascending growth was faster (P < .001), whereas in males, SoV growth was faster (P = .005), corrected for covariates. Unadjusted 10-year survival was 72.5% [95% confidence interval (CI) 67.8%-77.6%] for females and 78.3% (95% CI 75.3%-81.3%) for males (P = .010). Twenty-three type A dissections occurred, with an incidence rate of 8.2/1000 patient-years (95% CI 4.4-14.1) in females and 2.4/1000 patient-years (95% CI 1.2-4.5) in males [incidence rate ratio females/males: 3.4 (95% CI 1.5-8.0; P = .004)]. CONCLUSIONS: In patients having entered a diagnostic programme, involvement of aortic segments and age- and segment-related growth patterns differ between women and men with AscAA, particularly at an older age. Unravelling of these intertwined observations will provide a deeper understanding of AscAA progression and outcome in women and men and can be used as an evidence base for patient-tailored clinical guideline development.

7.
Adv Sci (Weinh) ; : e2403028, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38946620

RESUMO

Superhydrophobic surfaces (SHS) exhibit a pronounced ability to resist wetting. When immersed in water, water does not penetrate between the microstructures of the SHS. Instead, a thin layer of trapped gas remains, i.e., plastron. This fractional wetting is also known as the Cassie-Baxter state (CB). Impairment of superhydrophobicity occurs when water penetrates the plastron and, when complete wetting is achieved, a Wenzel state (W) results. Subsequent recovery back to CB state is one of the main challenges in the field of SHS wetting. Current methods for plastron recovery require complex mechanical or chemical integration, are time-consuming or lack spatial control. Here an on-demand, contact-less approach for performing facile transitions between these wetting states at micrometer length scales is proposed. This is achieved by the use of acoustic radiation force (ARF) produced by high-intensity focused ultrasound (HIFU). Switching from CB to W state takes <100 µs, while the local recovery back to CB state takes <45 s. To the best of authors knowledge, this is the first demonstration of ARF-induced manipulation of the plastron enabling facile two-way controlled switching of wetting states.

8.
Adv Sci (Weinh) ; : e2403366, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953394

RESUMO

Bubbles and foams are often removed via chemical defoamers and/or mechanical agitation. Designing surfaces that promote chemical-free and energy-passive bubble capture is desirable for numerous industrial processes, including mineral flotation, wastewater treatment, and electrolysis. When immersed, super-liquid-repellent surfaces form plastrons, which are textured solid topographies with interconnected gas domains. Plastrons exhibit the remarkable ability of capturing bubbles through coalescence. However, the two-step mechanics of plastron-induced bubble coalescence, namely, rupture (initiation and location) and subsequent absorption (propagation and drainage) are not well understood. Here, the influence of 1) topographical feature size and 2) gas fraction on bubble capture dynamics is investigated. Smaller feature sizes accelerate rupture while larger gas fractions markedly improve absorption. Rupture is initiated solely on solid domains and is more probable near the edges of solid features. Yet, rupture time becomes longer as solid fraction increases. This counterintuitive behavior represents unexpected complexities. Upon rupture, the bubble's moving liquid-solid contact line influences its absorption rate and equilibrium state. These findings show the importance of rationally minimizing surface feature sizes and contact line interactions for rapid bubble rupture and absorption. This work provides key design principles for plastron-induced bubble coalescence, inspiring future development of industrially-relevant surfaces for underwater bubble capture.

9.
Sci Rep ; 14(1): 17225, 2024 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-39060313

RESUMO

The emergence of antimicrobial resistance has created an urgent need for alternative treatments against bacterial pathogens. Here, we investigated kinase inhibitors as potential host-directed therapies (HDTs) against intracellular bacteria, specifically Salmonella Typhimurium (Stm) and Mycobacterium tuberculosis (Mtb). We screened 827 ATP-competitive kinase inhibitors with known target profiles from two Published Kinase Inhibitor Sets (PKIS1 and PKIS2) using intracellular infection models for Stm and Mtb, based on human cell lines and primary macrophages. Additionally, the in vivo safety and efficacy of the compounds were assessed using zebrafish embryo infection models. Our screen identified 11 hit compounds for Stm and 17 hit compounds for Mtb that were effective against intracellular bacteria and non-toxic for host cells. Further experiments were conducted to prioritize Stm hit compounds that were able to clear the intracellular infection in primary human macrophages. From these, two structurally related Stm hit compounds, GSK1379738A and GSK1379760A, exhibited significant activity against Stm in infected zebrafish embryos. In addition, we identified compounds that were active against intracellular Mtb, including morpholino-imidazo/triazolo-pyrimidinones that target PIK3CB, as well as 2-aminobenzimidazoles targeting ABL1. Overall, this study provided insights into kinase targets acting at the host-pathogen interface and identified several kinase inhibitors as potential HDTs.


Assuntos
Macrófagos , Mycobacterium tuberculosis , Inibidores de Proteínas Quinases , Salmonella typhimurium , Peixe-Zebra , Animais , Humanos , Salmonella typhimurium/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/enzimologia , Inibidores de Proteínas Quinases/farmacologia , Macrófagos/microbiologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Infecções por Salmonella/tratamento farmacológico , Infecções por Salmonella/microbiologia , Antibacterianos/farmacologia , Linhagem Celular , Embrião não Mamífero/efeitos dos fármacos , Tuberculose/tratamento farmacológico , Tuberculose/microbiologia
10.
Crit Rev Microbiol ; : 1-21, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916142

RESUMO

Mycobacterium tuberculosis (Mtb) is the causative pathogen of tuberculosis, the most lethal infectious disease resulting in 1.3 million deaths annually. Treatments against Mtb are increasingly impaired by the growing prevalence of antimicrobial drug resistance, which necessitates the development of new antibiotics or alternative therapeutic approaches. Upon infecting host cells, predominantly macrophages, Mtb becomes critically dependent on lipids as a source of nutrients. Additionally, Mtb produces numerous lipid-based virulence factors that contribute to the pathogen's ability to interfere with the host's immune responses and to create a lipid rich environment for itself. As lipids, lipid metabolism and manipulating host lipid metabolism play an important role for the virulence of Mtb, this review provides a state-of-the-art overview of mycobacterial lipid metabolism and concomitant role of host metabolism and host-pathogen interaction therein. While doing so, we will emphasize unexploited bacteria-directed and host-directed drug targets, and highlight potential synergistic drug combinations that hold promise for the development of new therapeutic interventions.

11.
Am J Dermatopathol ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38916235

RESUMO

ABSTRACT: Follicular hybrid cysts are uncommon entities derived from 2 or more components of the folliculo-sebaceous-apocrine unit. The pathogenesis of follicular hybrid cysts is uncertain; however, they are proposed to derive from the multipotent nature of follicular stem cells. Myotonic dystrophy type 1 is an inherited muscular dystrophy caused by an unstable trinucleotide repeat expansion in the myotonic dystrophy protein kinase gene, notably associated with multiple pilomatricomas. We report a novel case of multiple follicular hybrid tumors presenting in association with myotonic dystrophy type 1. We suspect that multipotent follicular stem cells, under the influence of the hypermutability phenotype present in myotonic dystrophy type 1, contributed to the pathogenesis of multiple follicular hybrid tumors in our patient.

12.
JAMA Dermatol ; 160(7): 741-745, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38809569

RESUMO

Importance: Masculinizing gender-affirming hormonal therapy is associated with the development of acne. While isotretinoin is a highly effective acne treatment, little is known about its effectiveness and safety among transgender and gender-diverse individuals receiving gender-affirming hormonal therapy. Objective: To evaluate clinical outcomes of isotretinoin among transgender and gender-diverse individuals receiving gender-affirming hormonal therapy. Design, Setting, and Participants: This multicenter retrospective case series study was conducted at 4 medical centers: Mass General Brigham, University of Pennsylvania, Emory University, and Fenway Health. It included patients aged between 12 and 49 years who were receiving masculinizing gender-affirming hormonal therapy and prescribed isotretinoin for the management of acne between August 14, 2015, and September 20, 2023. Exposure: Isotretinoin therapy for the management of acne. Main Outcomes and Measures: The percentage of patients experiencing improvement or clearance of acne, as well as rates of acne recurrence. Adverse effects and reasons for treatment discontinuation were also evaluated. Results: Among 55 included patients, the mean (SD) age was 25.4 years; 4 (7.3%) were Asian, 2 (3.6%) were Black, 4 (7.2%) were Hispanic, 1 was (1.8%) multiracial, and 36 (65.5%) were White. The median isotretinoin course duration was 6 months (IQR, 4.0-8.0), with a median cumulative dose of 132.7 mg/kg (IQR, 66.4-168.5); the cumulative dose was less than 90 mg/kg for 16 patients (29.1%) and less than 120 mg/kg for 22 patients (40.0%). Isotretinoin was associated with improvement in 48 patients (87.3%) and clearance in 26 patients (47.3%). For the 33 patients treated with a cumulative dose of 120 mg/kg or more, these rates increased to 32 patients (97.0%) and 21 patients (63.6%), respectively. Among the 20 patients who achieved acne clearance and had any subsequent health care encounters, the risk of recurrence was 20.0% (n = 4). The most frequently reported adverse effects were dryness (n = 44; 80.0%), joint pain (n = 8; 14.5%), and eczema (n = 5; 9.1%). Laboratory abnormalities were uncommon. Reasons for premature treatment discontinuation included cost, pharmacy issues, adverse effects, logistical reasons (scheduling), and wound healing concerns for gender-affirming surgery. Conclusion and Relevance: In this case series study of individuals with acne who were receiving masculinizing gender-affirming hormonal therapy and underwent isotretinoin treatment, isotretinoin was often effective and well tolerated. However, premature treatment discontinuation was common and associated with poorer outcomes. Further efforts are needed to understand optimal dosing and treatment barriers to improve outcomes in transgender and gender-diverse individuals receiving masculinizing gender-affirming hormonal therapy.


Assuntos
Acne Vulgar , Fármacos Dermatológicos , Isotretinoína , Pessoas Transgênero , Humanos , Isotretinoína/administração & dosagem , Isotretinoína/efeitos adversos , Acne Vulgar/tratamento farmacológico , Estudos Retrospectivos , Masculino , Feminino , Pessoas Transgênero/estatística & dados numéricos , Adolescente , Adulto , Fármacos Dermatológicos/administração & dosagem , Fármacos Dermatológicos/efeitos adversos , Adulto Jovem , Criança , Resultado do Tratamento , Pessoa de Meia-Idade , Recidiva
13.
Adv Sci (Weinh) ; 11(26): e2401016, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38696594

RESUMO

Despite attractive cost-effectiveness, scalability, and superior stability, carbon-based printable perovskite solar cells (CPSCs) still face moisture-induced degradation that limits their lifespan and commercial potential. Here, the moisture-preventing mechanisms of thin nanostructured super-repellent coating (advancing contact angle >167° and contact angle hysteresis 7°) integrated into CPSCs are investigated for different moisture forms (falling water droplets vs water vapor vs condensed water droplets). It is shown that unencapsulated super-repellent CPSCs have superior performance under continuous droplet impact for 12 h (rain falling experiments) compared to unencapsulated pristine (uncoated) CPSCs that degrade within seconds. Contrary to falling water droplets, where super-repellent coating serves as a shield, water vapor is found to physisorb through porous super-repellent coating (room temperature and relative humidity, RH 65% and 85%) that increase the CPSCs performance for 21% during ≈43 d similarly to pristine CPSCs. It is further shown that water condensation forms within or below the super-repellent coating (40 °C and RH 85%), followed by chemisorption and degradation of CPSCs. Because different forms of water have distinct effects on CPSC, it is suggested that future standard tests for repellent CPSCs should include rain falling and condensate formation tests. The findings will thus inspire the development of super-repellent coatings for moisture prevention.

14.
Environ Epidemiol ; 8(3): e308, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38799262

RESUMO

Background: PM2.5, NO2, and O3 contribute to the development of adverse pregnancy complications. While studies have investigated the independent effects of these exposures, literature on their combined effects is limited. Our objective was to study the multipollutant effects of PM2.5, NO2, and O3 on maternal systemic C-reactive protein (CRP) levels. Methods: We used data from 1170 pregnant women enrolled in the Maternal-Infant Research on Environmental Chemicals Study (MIREC) study in Canada. Air pollution exposures were assigned to each participant based on residential location. CRP was measured in third-trimester blood samples. We fit multipollutant linear regression models and evaluated the effects of air pollutant mixtures (14-day averages) using repeated-holdout Weighted Quantile Sum (WQS) regression and by calculating the Air Quality Health Index (AQHI). Results: In multipollutant models adjusting for NO2, O3, and green space, each interquartile range (IQR) increase in 14-day average PM2.5 (IQR: 6.9 µg/m3) was associated with 27.1% (95% confidence interval [CI] = 6.2, 50.7) higher CRP. In air pollution mixture models adjusting for green space, each IQR increase in AQHI was associated with 37.7% (95% CI = 13.9, 66.5) higher CRP; and an IQR increase in the WQS index was associated with 78.6% (95% CI = 29.7, 146.0) higher CRP. Conclusion: PM2.5 has the strongest relationship of the individual pollutants examined with maternal blood CRP concentrations. Mixtures incorporating all three pollutants, assessed using the AQHI and WQS index, showed stronger relationships with CRP compared with individual pollutants and illustrate the importance of conducting multipollutant analyses.

15.
Front Cell Infect Microbiol ; 14: 1367938, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590439

RESUMO

The increasing prevalence of antimicrobial-resistant Staphylococcus aureus strains, especially methicillin-resistant S. aureus (MRSA), poses a threat to successful antibiotic treatment. Unsuccessful attempts to develop a vaccine and rising resistance to last-resort antibiotics urge the need for alternative treatments. Host-directed therapy (HDT) targeting critical intracellular stages of S. aureus emerges as a promising alternative, potentially acting synergistically with antibiotics and reducing the risk of de novo drug resistance. We assessed 201 ATP-competitive kinase inhibitors from Published Kinase Inhibitor Sets (PKIS1 and PKIS2) against intracellular MRSA. Seventeen hit compounds were identified, of which the two most effective and well-tolerated hit compounds (i.e., GW633459A and GW296115X) were selected for further analysis. The compounds did not affect planktonic bacterial cultures, while they were active in a range of human cell lines of cervical, skin, lung, breast and monocyte origin, confirming their host-directed mechanisms. GW633459A, structurally related to lapatinib, exhibited an HDT effect on intracellular MRSA independently of its known human epidermal growth factor receptor (EGFR)/(HER) kinase family targets. GW296115X activated adenosine monophosphate-activated protein kinase (AMPK), thereby enhancing bacterial degradation via autophagy. Finally, GW296115X not only reduced MRSA growth in human cells but also improved the survival rates of MRSA-infected zebrafish embryos, highlighting its potential as HDT.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Animais , Staphylococcus aureus , Peixe-Zebra , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções Estafilocócicas/microbiologia , Testes de Sensibilidade Microbiana
16.
Neth Heart J ; 32(7-8): 270-275, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38653922

RESUMO

BACKGROUND: During transcatheter aortic valve implantation (TAVI), secondary access is required for angiographic guidance and temporary pacing. The most commonly used secondary access sites are the femoral artery (angiographic guidance) and the femoral vein (temporary pacing). An upper extremity approach using the radial artery and an upper arm vein instead of the lower extremity approach using the femoral artery and femoral vein may reduce clinically relevant secondary access site-related bleeding complications, but robust evidence is lacking. TRIAL DESIGN: The TAVI XS trial is a multicentre, randomised, open-label clinical trial with blinded evaluation of endpoints. A total of 238 patients undergoing transfemoral TAVI will be included. The primary endpoint is the incidence of clinically relevant bleeding (i.e. Bleeding Academic Research Consortium (BARC) type 2, 3 or 5 bleeding) of the randomised secondary access site (either diagnostic or pacemaker access, or both) within 30 days after TAVI. Secondary endpoints include time to mobilisation after TAVI, duration of hospitalisation, any BARC type 2, 3 or 5 bleeding, and early safety at 30 days according to Valve Academic Research Consortium­3 criteria. CONCLUSION: The TAVI XS trial is the first randomised trial comparing an upper extremity approach to a lower extremity approach with regard to clinically relevant secondary access site-related bleeding complications. The results of this trial will provide important insights into the safety and efficacy of an upper extremity approach in patients undergoing transfemoral TAVI.

17.
Proc Natl Acad Sci U S A ; 121(17): e2315214121, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38621127

RESUMO

Superhydrophobic surfaces are often seen as frictionless materials, on which water is highly mobile. Understanding the nature of friction for such water-repellent systems is central to further minimize resistance to motion and energy loss in applications. For slowly moving drops, contact-line friction has been generally considered dominant on slippery superhydrophobic surfaces. Here, we show that this general rule applies only at very low speed. Using a micropipette force sensor in an oscillating mode, we measure the friction of water drops approaching or even equaling zero contact-line friction. We evidence that dissipation then mainly stems from the viscous shearing of the air film (plastron) trapped under the liquid. Because this force is velocity dependent, it can become a serious drag on surfaces that look highly slippery from quasi-static tests. The plastron thickness is found to be the key parameter that enables the control of this special friction, which is useful information for designing the next generation of ultraslippery water-repellent coatings.

18.
Langmuir ; 40(17): 9059-9067, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38621291

RESUMO

When a droplet interacts with a water-repellent surface, its triple-phase contact line typically exhibits varying contact angles, which can vary from point-to-point across the surface. Consequently, measuring the contact angles along the contact line would provide a better representation of the wetting properties of the surface than a single average contact angle. However, an effective method for estimating the local contact angle along the contact line on opaque hydrophobic surfaces is currently lacking. Here we present a method that combines through-drop imaging of the wetting interface during a sliding experiment with Finite Element Modeling of the droplet to estimate contact angle values along the contact line. Using this method, the mean advancing and receding contact angles were measured on four types of hydrophobic samples with contact angles between 99 and 178.9°. The method was further used to produce detailed advancing and receding contact angle maps of surfaces with wetting patterns with an unprecedented resolution of 3 µm.

19.
Clin Perinatol ; 51(1): 113-126, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38325937

RESUMO

Pulmonary hypertension in the neonatal population can be acute or chronic and carries significant risk for morbidity and mortality. It can be idiopathic but more often is associated with comorbid pulmonary and heart disease. There are several pharmacotherapeutics aimed at pulmonary vasodilation. This review highlights the most common agents as well as those on the horizon for the treatment of pulmonary hypertension in the neonate.


Assuntos
Hipertensão Pulmonar , Óxido Nítrico , Recém-Nascido , Humanos , Óxido Nítrico/uso terapêutico , Hipertensão Pulmonar/tratamento farmacológico , Vasodilatação , Pulmão , Administração por Inalação
20.
J Mass Spectrom Adv Clin Lab ; 31: 49-58, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38375486

RESUMO

Objectives: Ketone bodies (KBs) serve as important energy sources that spare glucose, providing the primary energy for cardiac muscle, skeletal muscle during aerobic exercise, and the brain during periods of catabolism. The levels and relationships between the KBs are critical indicators of metabolic health and disease. However, challenges in separating isomeric KBs and concerns about sample stability have previously limited their clinical measurement. Methods: A novel 6.5-minute liquid chromatography-mass spectrometry-based assay was developed, enabling the precise measurement of alpha-, beta- and gamma-hydroxybutyrate, beta-hydroxyisobutyrate, and acetoacetate. This method was fully validated for human serum and plasma samples by investigating extraction efficiency, matrix effects, accuracy, recovery, intra- and inter-precision, linearity, lower limit of quantitation (LLOQ), carryover, specificity, stability, and more. From 107 normal samples, reference ranges were established for all analytes and the beta-hydroxybutyrate/acetoacetate ratio. Results: All five analytes were adequately separated chromatographically. An extraction efficiency between 80 and 120 % was observed for all KBs. Accuracy was evaluated through spike and recovery using 10 random patient samples, with an average recovery of 85-115 % for all KBs and a coefficient of variation of ≤ 3 %. Coefficients of variation for intra- and inter-day imprecision were < 5 %, and the total imprecision was < 10 %. No significant interferences were observed. Specimens remained stable for up to 6 h on ice or 2 h at room temperature. Conclusions: The developed method is highly sensitive and robust. It has been validated for use with human serum and plasma, overcoming stability concerns and providing a reliable and efficient quantitative estimation of ketone bodies.

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