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1.
J Clin Med ; 13(16)2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39200889

RESUMO

Background: Continuous vital sign monitoring via wearable technology, combined with algorithm-based notifications, has been utilized for early detection of patient deterioration. In this retrospective observational study, we summarize a large-scale implementation of a continuous monitoring system in medical-surgical units of two hospitals over the course of fifteen (15) months. Methods: An FDA-cleared wireless monitoring device (BioButton®, BioIntelliSense Inc., Golden, CO, USA), was placed on each patient upon admission. The wearable device measures heart rate and respiratory rate at rest, skin temperature, and patient activity levels. High-frequency data (up to 1440 measurements per day) are transmitted to display in exception management software (BioDashboard™, version 2.9, BioIntelliSense Inc.). Algorithmic and rules-based notifications are triggered based on clinical and statistical trending criteria. We present (i) agreement of device readings with bedside charted measurements, (ii) the frequency of notifications, (iii) the occurrence of notifications prior to clinical deterioration events, and (iv) impact on clinical management, including early data on length of stay (LOS). Results: In total, 11,977 patient encounters were monitored at two sites. Bias ±95% limits of agreement were 1.8 ± 12.5 for HR and 0.4 ± 8.0 for RR. The rates of notifications were 0.97 and 0.65 per patient-day at Sites 1 and 2, respectively. Among clinical deteriorations, 73% (66%) had at least one notification within 24 h prior at Site 1 (Site 2). At Site 1, there were 114 cases for which a notification led to a new or changed physician's order. LOS in the first unit monitored by the system exhibited a decreasing trend from 3.07 days to 2.75 days over 12 months. Conclusions: Wearable continuous vital sign monitoring with the BioIntelliSense BioButton® system enables early detection of clinical deterioration.

2.
ACS Earth Space Chem ; 8(8): 1609-1622, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39166261

RESUMO

Variable wind speeds over the ocean can have a significant impact on the formation mechanism and physical-chemical properties of sea spray aerosols (SSA), which in turn influence their climate-relevant impacts. Herein, for the first time, we investigate the effects of wind speed on size-dependent morphology and composition of individual nascent SSA generated from wind-wave interactions of natural seawater within a wind-wave channel as a function of size and their particle-to-particle variability. Filter-based thermal optical analysis, atomic force microscopy (AFM), AFM infrared spectroscopy (AFM-IR), and scanning electron microscopy (SEM) were employed in this regard. This study focuses on SSA with sizes within 0.04-1.8 µm generated at two wind speeds: 10 m/s, representing a wind lull scenario over the ocean, and 19 m/s, indicative of the wind speeds encountered in stormy conditions. Filter-based measurements revealed a reduction of the organic mass fraction as the wind speed increases. AFM imaging at 20% relative humidity of individual SSA identified six main morphologies: prism-like, rounded, core-shell, rod, rod inclusion core-shell, and aggregates. At 10 m/s, most SSA were rounded, while at 19 m/s, core-shells became predominant. Based on AFM-IR, rounded SSA at both wind speeds had similar composition, mainly composed of aliphatic and oxygenated species, whereas the shells of core-shells displayed more oxygenated organics at 19 m/s and more aliphatic organics at 10 m/s. Collectively, our observations can be attributed to the disruption of the sea surface microlayer film structure at higher wind speeds. The findings reveal a significant impact of wind speed on morphology and composition of SSA, which should be accounted for accurate assessment of their climate effects.

3.
J Burn Care Res ; 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39167451

RESUMO

Recent studies indicate that YouTube has become a primary source of healthcare information for patients. Videos about skin graft procedures on YouTube have accumulated millions of views, yet there lacks a publication investigating the educational quality of this content. With current literature revealing misleading healthcare information found on YouTube, this study aims to evaluate the educational quality of videos related to skin graft procedures. YouTube was searched for various terms such as "Skin Graft Procedures" and "Skin Graft Surgery." 105 videos were assessed, with 21 excluded. Four independent reviewers rated the material with the Global Quality Scale (5 = highest quality, 1 = lowest quality) to judge educational value. Viewership, source, modality, and date of upload were also collected from each video and compiled for further analysis. The average Global Quality Scale was 2.60 amongst all videos, with videos led by physicians recording significantly higher scores than those not led by physicians (p<0.01). In comparing educational modalities, physician-led presentations provided the highest educational value, whereas live surgeries and consumer-friendly content contained low educational quality (p<0.01). Assessing videos split into cohorts based on viewership noted a significantly higher Global Quality Scale in videos with lower view counts (p<0.05). Skin graft videos on YouTube largely provide low quality information. Videos performed by physicians, particularly physician-led presentations, significantly improved the educational quality of skin graft content. Physicians must involve themselves in enhancing the quality of online content to better guide patients in navigating treatment options and making healthcare decisions.

4.
J Acoust Soc Am ; 156(1): 65-80, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949286

RESUMO

Environment estimation is a challenging task in reverberant settings such as the underwater and indoor acoustic domains. The locations of reflective boundaries, for example, can be estimated using acoustic echoes and leveraged for subsequent, more accurate localization and mapping. Current boundary estimation methods are constrained to high signal-to-noise ratios or are customized to specific environments. Existing methods also often require a correct assignment of echoes to boundaries, which is difficult if spurious echoes are detected. To evade these limitations, a convolutional neural network (NN) method is developed for robust two-dimensional boundary estimation, given known emitter and receiver locations. A Hough transform-inspired algorithm is leveraged to transform echo times of arrival into images, which are amenable to multi-resolution regression by NNs. The same architecture is trained on transform images of different resolutions to obtain diverse NNs, deployed sequentially for increasingly refined boundary estimation. A correct echo labeling solution is not required, and the method is robust to reverberation. The proposed method is tested in simulation and for real data from a water tank, where it outperforms state-of-the-art alternatives. These results are encouraging for the future development of data-driven three-dimensional environment estimation with high practical value in underwater acoustic detection and tracking.

5.
J Phys Chem B ; 128(30): 7438-7444, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39037039

RESUMO

Electrolytes are central to many technological applications, as well as life itself. The behavior and properties of electrolytes are often described in terms of ion pairs, whereby ions associate as either contact ion pairs (in which ions are "touching") solvent-separated ion pairs (in which ions' solvent shells overlap) or solvent-solvent-separated ion pairs (in which ions' solvent shells are distinct). However, this paradigm is generally restricted to statistically averaged descriptions of solution structure and ignores temporal behavior. Here we elucidate the time-resolved dynamics of these ion-ion interactions in aqueous metal chloride electrolytes using the partial van Hove correlation function, based on polarizable molecular dynamics simulations. Our results show that the existence and persistence of ion pairs in aqueous metal chloride electrolytes should not be assumed a priori, but in fact are ion specific features of the solution with lifetimes on subpicosecond time scales.

6.
J Exp Biol ; 227(16)2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39054898

RESUMO

Adult, lab-reared, highland deer mice acclimate to hypoxia by increasing reliance on carbohydrates to fuel exercise. Yet neither the underlying mechanisms for this shift in fuel use nor the impact of lifetime hypoxia exposure experienced in high alpine conditions, are fully understood. Thus, we assessed the use of fuel during exercise in wild highland deer mice running in their native environment. We examined a key step in muscle carbohydrate oxidation - the regulation of pyruvate dehydrogenase (PDH) - during exercise at altitude in wild highlanders and in first generation (G1) lab-born and -raised highlanders acclimated to normoxia or hypoxia. PDH activity was also determined in the gastrocnemius of G1 highlanders using an in situ muscle preparation. We found that wild highlanders had a high reliance on carbohydrates while running in their native environment, consistent with data from hypoxia-acclimated G1 highlanders. PDH activity in the gastrocnemius was similar post exercise between G1 and wild highlanders. However, when the gastrocnemius was stimulated at a light work rate in situ, PDH activity was higher in hypoxia-acclimated G1 highlanders and was associated with lower intramuscular lactate levels. These findings were supported by lower PDH kinase 2 protein production in hypoxia-acclimated G1 mice. Our findings indicate that adult phenotypic plasticity in response to low oxygen is sufficient to increase carbohydrate reliance during exercise in highland deer mice. Additionally, variation in PDH regulation with hypoxia acclimation contributes to shifts in whole-animal patterns of fuel use and is likely to improve exercise performance via elevated energy yield per mole of O2. .


Assuntos
Altitude , Músculo Esquelético , Peromyscus , Condicionamento Físico Animal , Complexo Piruvato Desidrogenase , Animais , Músculo Esquelético/metabolismo , Músculo Esquelético/enzimologia , Peromyscus/fisiologia , Complexo Piruvato Desidrogenase/metabolismo , Masculino , Aclimatação , Hipóxia/metabolismo , Feminino
7.
Phys Chem Chem Phys ; 26(31): 20750-20759, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-38988220

RESUMO

The use of solvents is ubiquitous in chemistry. Empirical parameters, such as the Kamlet-Taft parameters and Gutmann donor/acceptor numbers, have long been used to predict and quantify the effects solvents have on chemical phenomena. Collectively however, such parameters are unsatisfactory, since each describes ultimately the same non-covalent solute-solvent and solute-solute interactions in completely disparate ways. Here we hypothesise that empirical solvent parameters are essentially proxy measures of the electrostatic terms that dominate solvent-solute interactions. On the basis of this hypothesis, we develop a new fundamental descriptor of these interactions, , and show that it is a self-consistent, probe-free, first principles alternative to established empirical solvent parameters.

8.
Artigo em Inglês | MEDLINE | ID: mdl-39059702

RESUMO

For small mammals, such as mice, cannulation procedures can be quite challenging, limiting research associated with tracing isotopically labelled substrates at the whole-animal level. When cannulation in mice is possible, assessment of substrate use is further limited to when mice are either under anesthesia or are at rest, as there are no studies directly quantifying substrate use during exercise in mice. The use of isotopic tracer techniques has greatly advanced our knowledge in understanding how metabolic substrates (carbohydrates, amino acids, and fatty acids) contribute to whole-body metabolism. However, research regarding tissue-specific fuel use contributions to whole-body energy expenditure in mice at varying metabolic intensities (i.e., exercise) is lacking, despite the popularity of using mice in a variety of metabolic models. In this commentary, we briefly discuss the methodologies, advantages, and disadvantages of using radiolabelled, positron emission, and stable isotopes with a specific focus on fatty acids. We highlight recent mouse studies that have used creative experimental designs employing the use of isotopic tracer techniques and we briefly discuss how these methodologies can be further pursued to deepen our understanding of substrate use during exercise. Lastly, we show findings of a recent study we performed using a radiolabelled fatty acid tracer (14C-bromopalmitic acid) to determine fatty acid uptake in 16 muscles, two brown and two white adipose tissue depots during submaximal exercise in deer mice.


Assuntos
Metabolismo Energético , Animais , Camundongos , Metabolismo Energético/fisiologia , Ácidos Graxos/metabolismo , Condicionamento Físico Animal
9.
Adv Colloid Interface Sci ; 331: 103238, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38917595

RESUMO

Diffuse soft matter interfaces take many forms, from end-tethered polymer brushes or adsorbed surfactants to self-assembled layers of lipids. These interfaces play crucial roles across a multitude of fields, including materials science, biophysics, and nanotechnology. Understanding the nanostructure and properties of these interfaces is fundamental for optimising their performance and designing novel functional materials. In recent years, reflectometry techniques, in particular neutron reflectometry, have emerged as powerful tools for elucidating the intricate nanostructure of soft matter interfaces with remarkable precision and depth. This review provides an overview of selected recent developments in reflectometry and their applications for illuminating the nanostructure of diffuse interfaces. We explore various principles and methods of neutron and X-ray reflectometry, as well as ellipsometry, and discuss advances in their experimental setups and data analysis approaches. Improvements to experimental neutron reflectometry methods have enabled greater time resolution in kinetic measurements and elucidation of diffuse structure under shear or confinement, while innovation in analysis protocols has significantly reduced data processing times, facilitated co-refinement of reflectometry data from multiple instruments and provided greater-than-ever confidence in proposed structural models. Furthermore, we highlight some significant research findings enabled by these techniques, revealing the organisation, dynamics, and interfacial phenomena at the nanoscale. We also discuss future directions and potential advancements in reflectometry techniques. By shedding light on the nanostructure of diffuse interfaces, reflectometry techniques enable the rational design and tailoring of interfaces with enhanced properties and functionalities.

10.
Artigo em Inglês | MEDLINE | ID: mdl-38945522

RESUMO

Animals living at high-altitude are faced with unremitting low oxygen availability. This can make it difficult to perform daily tasks that require increases in aerobic metabolism. An activity important for survival is aerobic locomotion, and the rapid recovery of muscle metabolism post exercise. Past work shows that hypoxia acclimated high-altitude mice (Peromyscus maniculatus) have a greater reliance on carbohydrates to power exercise than low altitude mice. However, it is unclear how quickly after aerobic exercise these mice can recovery and replenish muscle glycogen stores. The gastrocnemius muscle of high-altitude deer mice has a more aerobic phenotype and a greater capacity to oxidize lipids than low altitude deer mice. This suggests that high altitude mice may recover more rapidly from exercise than their lowland counterparts due to a greater capacity to support glycogen replenishment using intramuscular triglycerides (IMTG). To explore this possibility, we used low- and high-altitude native deer mice born and raised in common lab conditions and acclimated to chronic hypoxia. We determined changes in oxygen consumption following 15 min of aerobic exercise in 12% O2 and sampled skeletal muscles and liver at various time points during recovery to examine changes in key metabolites, including glycogen and IMTG. We found depletion in glycogen stores during exercise only in lowlanders, which returned to resting levels following 90 min of recovery. In contrast, IMTG did not change significantly with exercise or during recovery in either population. These data suggest that exercise recovery is influenced by altitude ancestry in deer mice.


Assuntos
Altitude , Glicogênio , Hipóxia , Músculo Esquelético , Consumo de Oxigênio , Peromyscus , Condicionamento Físico Animal , Animais , Músculo Esquelético/metabolismo , Glicogênio/metabolismo , Condicionamento Físico Animal/fisiologia , Hipóxia/metabolismo , Hipóxia/fisiopatologia , Consumo de Oxigênio/fisiologia , Aclimatação/fisiologia , Masculino , Triglicerídeos/metabolismo , Fígado/metabolismo
11.
J Plast Reconstr Aesthet Surg ; 94: 141-149, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38781834

RESUMO

PURPOSE: Reduction mammaplasty has transitioned into a largely outpatient procedure in the United States. Following planned outpatient procedures, patients may still be admitted for additional inpatient care, incurring clinical and economic burden. Prior literature has not explored the preoperative and perioperative determinants of extended lengths of stay (LOS) after breast reduction surgery. METHODS: Patients who underwent scheduled outpatient reduction mammaplasty were identified via current procedural terminology code from the 2013 to 2021 National Surgical Quality Improvement Program databases. The primary outcome was extended LOS, defined as an LOS greater than 1 day. The most significant predictor variables were identified through bivariate association, and a binary logistic regression model was used to characterize predictive associations (p < 0.05). RESULTS: In this study, 33,924 patients were included in the final cohort of planned outpatient reduction mammaplasty cases. Among them 325 (1.0%) patients had extended LOS. Concurrent liposuction, body contouring, and increased operative time were the most significant predictors of extended LOS (p < 0.001), followed by older age, higher body mass index, bleeding disorder, history of diabetes, higher American Society of Anesthesiologists class, and White race (p < 0.05). When adjusted for other confounding variables, extended LOS was also a significant predictor of increased risk of postoperative complications after discharge (OR: 1.85, 95% confidence intervals: 1.27-2.69, p = 0.0012). CONCLUSION: Extended LOS after planned outpatient reduction mammaplasty is associated with specific comorbidities, and is a significant predictor of postoperative complications following hospital discharge. DATA AVAILABILITY STATEMENT: The data that support the findings of this study are publicly available.


Assuntos
Procedimentos Cirúrgicos Ambulatórios , Tempo de Internação , Mamoplastia , Complicações Pós-Operatórias , Humanos , Mamoplastia/métodos , Feminino , Tempo de Internação/estatística & dados numéricos , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Ambulatórios/estatística & dados numéricos , Adulto , Complicações Pós-Operatórias/epidemiologia , Estados Unidos , Fatores de Risco , Duração da Cirurgia , Estudos Retrospectivos
12.
Sci Total Environ ; 926: 171537, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38460684

RESUMO

This study proposed and examined a new process flowsheet for treating neutral mine drainage (NMD) from an open-pit gold mine. The process consisted of three sequential stages: (1) in situ hydrotalcite (HT) precipitation; (2) low-cost carbon substrate driven microbial sulfate reduction; and (3) ferrosol reactive barrier for removing biogenic dissolved hydrogen sulfide (H2S). For concept validation, laboratory-scale columns were established and operated for a 140-days period with key process performance parameters regularly measured. At the end, solids recovered from various depths of the ferrosol column were analysed for elemental composition and mineral phases. Prokaryotic microbial communities in various process locations were characterised using 16S rRNA gene sequencing. Results showed that the Stage 1 HT-treatment substantially removed a range of elements (As, B, Ba, Ca, F, Zn, Si, and U) in the NMD, but not nitrate or sulfate. The Stage 2 sulfate reducing bioreactor (SRB) packed with 70 % (v/v) Eucalyptus woodchip, 1 % (w/v) ground (<1 mm) dried Typha biomass, and 10 % (w/v) NMD-pond sediment facilitated complete nitrate removal and stable sulfate removal of ca. 50 % (50 g-SO4 m-3 d-1), with an average H2S generation rate of 10 g-H2S m-3d-1. The H2S-removal performance of the Stage 3 ferrosol column was compared with a synthetic amorphous Fe-oxyhydroxide-amended sand control column. Although both columns facilitated excellent (95-100 %) H2S removal, the control column only enabled a further ca. 10 % sulfate reduction, giving an overall sulfate removal of 56 %. In contrast, the ferrosol enabled an extra 99.9 % sulfate reduction in the SRB effluent, leading to a near complete sulfate removal. Overall, the process successfully eliminated a range of metal/metalloid contaminants, nitrate, sulfate (2500 mg-SO4 L-1 in the NMD to <10 mg-SO4 L-1 in the final effluent) and H2S (>95 % removal). Further optimisation is required to minimise release of ferrous iron from the ferrosol barrier into the final effluent.


Assuntos
Hidróxido de Alumínio , Sulfeto de Hidrogênio , Hidróxido de Magnésio , RNA Ribossômico 16S , Nitratos , Sulfatos/química , Reatores Biológicos
13.
J Exp Biol ; 227(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38506250

RESUMO

During maximal cold challenge (cold-induced V̇O2,max) in hypoxia, highland deer mice (Peromyscus maniculatus) show higher rates of circulatory fatty acid delivery compared with lowland deer mice. Fatty acid delivery also increases with acclimation to cold hypoxia (CH) and probably plays a major role in supporting the high rates of thermogenesis observed in highland deer mice. However, it is unknown which tissues take up these fatty acids and their relative contribution to thermogenesis. The goal of this study was to determine the uptake of circulating fatty acids into 24 different tissues during hypoxic cold-induced V̇O2,max, by using [1-14C]2-bromopalmitic acid. To uncover evolved and environment-induced changes in fatty acid uptake, we compared lab-born and -raised highland and lowland deer mice, acclimated to either thermoneutral (30°C, 21 kPa O2) or CH (5°C, 12 kPa O2) conditions. During hypoxic cold-induced V̇O2,max, CH-acclimated highlanders decreased muscle fatty acid uptake and increased uptake into brown adipose tissue (BAT) relative to thermoneutral highlanders, a response that was absent in lowlanders. CH acclimation was also associated with increased activities of enzymes citrate synthase and ß-hydroxyacyl-CoA dehydrogenase in the BAT of highlanders, and higher levels of fatty acid translocase CD36 (FAT/CD36) in both populations. This is the first study to show that cold-induced fatty acid uptake is distributed across a wide range of tissues. Highland deer mice show plasticity in this fatty acid distribution in response to chronic cold hypoxia, and combined with higher rates of tissue delivery, this contributes to their survival in the cold high alpine environment.


Assuntos
Tecido Adiposo Marrom , Peromyscus , Animais , Peromyscus/fisiologia , Ácidos Graxos , Hipóxia , Aclimatação , Músculos , Termogênese/fisiologia , Temperatura Baixa
14.
Am J Physiol Regul Integr Comp Physiol ; 326(4): R297-R310, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38372126

RESUMO

The cold and hypoxic conditions at high altitude necessitate high metabolic O2 demands to support thermogenesis while hypoxia reduces O2 availability. Skeletal muscles play key roles in thermogenesis, but our appreciation of muscle plasticity and adaptation at high altitude has been hindered by past emphasis on only a small number of muscles. We examined this issue in deer mice (Peromyscus maniculatus). Mice derived from both high-altitude and low-altitude populations were born and raised in captivity and then acclimated as adults to normoxia or hypobaric hypoxia (12 kPa O2 for 6-8 wk). Maximal activities of citrate synthase (CS), cytochrome c oxidase (COX), ß-hydroxyacyl-CoA dehydrogenase (HOAD), hexokinase (HK), pyruvate kinase (PK), and lactate dehydrogenase (LDH) were measured in 20 muscles involved in shivering, locomotion, body posture, ventilation, and mastication. Principal components analysis revealed an overall difference in muscle phenotype between populations but no effect of hypoxia acclimation. High-altitude mice had greater activities of mitochondrial enzymes and/or lower activities of PK or LDH across many (but not all) respiratory, limb, core and mastication muscles compared with low-altitude mice. In contrast, chronic hypoxia had very few effects across muscles. Further examination of CS in the gastrocnemius showed that population differences in enzyme activity stemmed from differences in protein abundance and mRNA expression but not from population differences in CS amino acid sequence. Overall, our results suggest that evolved increases in oxidative capacity across many skeletal muscles, at least partially driven by differences in transcriptional regulation, may contribute to high-altitude adaptation in deer mice.NEW & NOTEWORTHY Most previous studies of muscle plasticity and adaptation in high-altitude environments have focused on a very limited number of skeletal muscles. Comparing high-altitude versus low-altitude populations of deer mice, we show that a large number of muscles involved in shivering, locomotion, body posture, ventilation, and mastication exhibit greater mitochondrial enzyme activities in the high-altitude population. Therefore, evolved increases in mitochondrial oxidative capacity across skeletal muscles contribute to high-altitude adaptation.


Assuntos
Altitude , Peromyscus , Animais , Peromyscus/fisiologia , Hipóxia/metabolismo , Músculo Esquelético/metabolismo , Aclimatação , Fenótipo
15.
Adv Mater ; 36(1): e2305937, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37689973

RESUMO

Oral delivery, while a highly desirable form of nanoparticle-drug administration, is limited by challenges associated with overcoming several biological barriers. Here, the authors study how fluorescent and poly(ethylene glycol)-coated (PEGylated) core-shell silica nanoparticles sized 5 to 50 nm interact with major barriers including intestinal mucus, intestinal epithelium, and stomach acid. From imaging fluorescence correlation spectroscopy studies using quasi-total internal reflection fluorescence microscopy, diffusion of nanoparticles through highly scattering mucus is progressively hindered above a critical hydrodynamic size around 20 nm. By studying Caco-2 cell monolayers mimicking the intestinal epithelia, it is observed that ultrasmall nanoparticles below 10 nm diameter (Cornell prime dots, [C' dots]) show permeabilities correlated with high absorption in humans from primarily enhanced passive passage through tight junctions. Particles above 20 nm diameter exclusively show active transport through cells. After establishing C' dot stability in artificial gastric juice, in vivo oral gavage experiments in mice demonstrate successful passage through the body followed by renal clearance without protein corona formation. Results suggest C' dots as viable candidates for oral administration to patients with a proven pathway towards clinical translation and may generate renewed interest in examining silica as a food additive and its effects on nutrition and health.


Assuntos
Portadores de Fármacos , Nanopartículas , Humanos , Ratos , Camundongos , Animais , Portadores de Fármacos/química , Células CACO-2 , Ratos Sprague-Dawley , Dióxido de Silício/química , Nanopartículas/química
16.
Langmuir ; 40(1): 335-347, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38117209

RESUMO

Pertinent to cryopreservation as well as energy storage and batteries, nonaqueous electrolytes and their mixtures with water were investigated. In particular, specific ion-induced effects on the modulation of a poly(N-isopropylacrylamide) (PNIPAM) brush were investigated in various dimethyl sulfoxide (DMSO)-water solvent mixtures. Spectroscopic ellipsometry and neutron reflectometry were employed to probe changes in brush swelling and structure, respectively. In water-rich solvents (i.e., pure water and 6 mol % DMSO), PNIPAM undergoes a swollen to collapsed thermotransition with increasing temperature, whereby a forward Hofmeister series was noted; K+ and Li+ electrolytes composed of SCN- and I- salted-in (stabilized) PNIPAM chains, and electrolytes of Cl- and Br- salted-out (destabilized) the polymer. The cation was seen to play a lesser role than that of the anion, merely modulating the magnitude of the anion effect. In 70 mol % DMSO, a collapsed to swollen thermotransition was noted for PNIPAM. Here, concentration-dependent specific ion effects were observed; a forward series was observed in 0.2 mol % electrolytes, whereas increasing the electrolyte concentration to 0.9 mol % led to a series reversal. While no thermotransition was observed in pure DMSO, a solvent-induced specific ion series reversal was noted; SCN- destabilized the brush and Cl- stabilized the brush. Both series reversals are attributed to the delicate balance of interactions between the solvent, solute (ion), and substrate (brush). Namely, the stability of the solvent clusters was hypothesized to drive polymer solvation.

17.
J Plast Reconstr Aesthet Surg ; 87: 205-207, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37898025

RESUMO

Given the lack of formal education on plastic surgery services during the preclinical years of medical school, many medical students commonly misunderstand the breadth and depth of the field. Shadowing is highly impactful in shaping students' desire to pursue surgery, but the impact of plastic surgery shadowing remains unexplored. The study design utilized an anonymous web-based survey containing questions surrounding prior interest in surgery, race, gender, medical school progress, and clinical versus OR shadowing. All medical students who participated in an ongoing, voluntary plastic surgery shadowing program over a two-year period were invited to complete the survey. Of the 54 students who shadowed during the study period, 43 (79.6%) returned the survey. Students reported an overall greater impact of OR shadowing than clinic shadowing on their interest in plastic surgery, approaching significance (p = 0.0527). On simple and multivariate regression, the number of times a student shadowed in the OR was the only statistically significant predictor of students' interest in plastic surgery (p = 0.0003). In general, the majority of students reported that their shadowing experience "significantly increased" (24.2%) or "somewhat increased" (45.5%) their interest in pursuing a career in plastic surgery. The impact of shadowing, particularly in the operating room, on students' interest in plastic surgery demonstrates the value of structured shadowing programs. Additionally, given the particularly influential effect of shadowing in the operating room, our results indicate that efforts may benefit most from facilitating student exposure to the hands-on aspects of the field.


Assuntos
Educação de Graduação em Medicina , Procedimentos de Cirurgia Plástica , Estudantes de Medicina , Cirurgia Plástica , Humanos , Escolha da Profissão , Educação de Graduação em Medicina/métodos
18.
Plast Reconstr Surg ; 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37843269

RESUMO

BACKGROUND: Given that gender-affirming surgery (GAS) is considered medically necessary for transgender and gender diverse (TGD) individuals who desire it, the aim of this study is to assess the concordance of insurance criteria for GAS with the most recent World Professional Association for Transgender Health (WPATH) Standards of Care Version 8 (SOC-8). METHODS: Insurance policies for coverage of gender-affirming genital ("bottom surgery"), chest ("top surgery"), and facial reconstruction from companies representing 80% of the market coverage in each state were evaluated. Policies were classified into three categories: no-coverage (NC), case-by-case (CC), and preauthorization (PA). Among PA policies, criteria for coverage of specific surgeries were analyzed for adherence to WPATH SOC-8. RESULTS: Bottom surgery policies were most concordant for age and gender dysphoria criteria, and transmasculine top surgery policies were most concordant for hormone therapy, continuous living in a congruent gender role, and referral criteria. transfeminine top surgery criteria were more restrictive than transmasculine criteria. The most discordant criteria was for hormone therapy, being required for at least 12 months prior to surgery in the majority of surveyed policies. Many specific procedures and treatments were excluded, especially facial GAS with cosmetic overlap. Additionally, reversal and revisionary surgeries were covered in less than 25% of policies. CONCLUSION: Compared to previous literature, insurance coverage and criteria alignment are becoming more concordant with medical guidelines. However, significant barriers to care are still present for GAS.

19.
Plast Reconstr Surg ; 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37815328

RESUMO

BACKGROUND: Despite established medical necessity, laws prohibiting coverage discrimination, and increasing numbers of transgender and gender diverse patients seeking gender-affirming surgeries (GAS), cost and restrictive insurance policies continue to be the most common barriers. As recent legislation places further restrictions on GAS, this study aims to provide an updated review of insurance policies and assess the relationship between legislative favorability and coverage. METHODS: Insurance policies of groups representing 80% market coverage in each state were collected for gender-affirming chest, genital and facial surgery. Policies were categorized based on previously published methodologies: never-covered (N), case-by-case (CC), and preauthorization (PA). The relationship between established scores of legislative favorability and policy coverage in each state was analyzed and compared across regions. RESULTS: Of the 316 analyzed policies, coverage was preauthorized most often for genital (94.0%), masculinizing top (93%), feminizing top (74%), and facial reconstruction (24%), respectively. Higher legislative scores in the Northeast and West, as well as individual states were predictive of increased genital, facial, and all forms of adolescent GAS, but were not correlated to chest GAS. CONCLUSION: Compared to previous studies, our findings suggest that there is a growing acceptance of GAS as medically necessary. However, the correlation between legislative scores and genital, face, and adolescent GAS coverage may suggest increased reliance on sociopolitical factors for access in the absence of comprehensive medical guidelines, which are more established for chest reconstruction. Significantly higher coverage of masculinizing versus feminizing chest surgery suggests additional burden of proof for GAS with a cosmetic overlap.

20.
Phys Chem Chem Phys ; 25(36): 24770-24782, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37671535

RESUMO

Hypersaline environments are ubiquitous in nature and are found in myriad technological processes. Recent empirical studies have revealed a significant discrepancy between predicted and observed screening lengths at high salt concentrations, a phenomenon referred to as underscreening. Herein we investigate underscreening using a cationic polyelectrolyte brush as an exemplar. Poly(2-(methacryloyloxy)ethyl)trimethylammonium (PMETAC) brushes were synthesised and their internal structural changes and swelling response was monitored with neutron reflectometry and spectroscopic ellipsometry. Both techniques revealed a monotonic brush collapse as the concentration of symmetric monovalent electrolyte increased. However, a non-monotonic change in brush thickness was observed in all multivalent electrolytes at higher concentrations, known as re-entrant swelling; indicative of underscreening. For all electrolytes, numerical self-consistent field theory predictions align with experimental studies in the low-to-moderate salt concentration regions. Analysis suggests that the classical theory of electrolytes is insufficient to describe the screening lengths observed at high salt concentrations and that the re-entrant polyelectrolyte brush swelling seen herein is consistent with the so-called regular underscreening phenomenon.

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