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1.
Nature ; 614(7947): 270-274, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36755170

RESUMEN

Photoelectrochemical (PEC) water splitting to produce hydrogen fuel was first reported 50 years ago1, yet artificial photosynthesis has not become a widespread technology. Although planar Si solar cells have become a ubiquitous electrical energy source economically competitive with fossil fuels, analogous PEC devices have not been realized, and standard Si p-type/n-type (p-n) junctions cannot be used for water splitting because the bandgap precludes the generation of the needed photovoltage. An alternative paradigm, the particle suspension reactor (PSR), forgoes the rigid design in favour of individual PEC particles suspended in solution, a potentially low-cost option compared with planar systems2,3. Here we report Si-based PSRs by synthesizing high-photovoltage multijunction Si nanowires (SiNWs) that are co-functionalized to catalytically split water. By encoding a p-type-intrinsic-n-type (p-i-n) superlattice within single SiNWs, tunable photovoltages exceeding 10 V were observed under 1 sun illumination. Spatioselective photoelectrodeposition of oxygen and hydrogen evolution co-catalysts enabled water splitting at infrared wavelengths up to approximately 1,050 nm, with the efficiency and spectral dependence of hydrogen generation dictated by the photonic characteristics of the sub-wavelength-diameter SiNWs. Although initial energy conversion efficiencies are low, multijunction SiNWs bring the photonic advantages of a tunable, mesoscale geometry and the material advantages of Si-including the small bandgap and economies of scale-to the PSR design, providing a new approach for water-splitting reactors.

2.
Annu Rev Physiol ; 85: 47-69, 2023 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-36351366

RESUMEN

The human lung cellular portfolio, traditionally characterized by cellular morphology and individual markers, is highly diverse, with over 40 cell types and a complex branching structure highly adapted for agile airflow and gas exchange. While constant during adulthood, lung cellular content changes in response to exposure, injury, and infection. Some changes are temporary, but others are persistent, leading to structural changes and progressive lung disease. The recent advance of single-cell profiling technologies allows an unprecedented level of detail and scale to cellular measurements, leading to the rise of comprehensive cell atlas styles of reporting. In this review, we chronical the rise of cell atlases and explore their contributions to human lung biology in health and disease.


Asunto(s)
Pulmón , Humanos , Adulto , Pulmón/fisiología
3.
Proc Natl Acad Sci U S A ; 120(9): e2220934120, 2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36802428

RESUMEN

Sea sponges are the largest marine source of small-molecule natural products described to date. Sponge-derived molecules, such as the chemotherapeutic eribulin, the calcium-channel blocker manoalide, and antimalarial compound kalihinol A, are renowned for their impressive medicinal, chemical, and biological properties. Sponges contain microbiomes that control the production of many natural products isolated from these marine invertebrates. In fact, all genomic studies to date investigating the metabolic origins of sponge-derived small molecules concluded that microbes-not the sponge animal host-are the biosynthetic producers. However, early cell-sorting studies suggested the sponge animal host may play a role particularly in the production of terpenoid molecules. To investigate the genetic underpinnings of sponge terpenoid biosynthesis, we sequenced the metagenome and transcriptome of an isonitrile sesquiterpenoid-containing sponge of the order Bubarida. Using bioinformatic searches and biochemical validation, we identified a group of type I terpene synthases (TSs) from this sponge and multiple other species, the first of this enzyme class characterized from the sponge holobiome. The Bubarida TS-associated contigs consist of intron-containing genes homologous to sponge genes and feature GC percentage and coverage consistent with other eukaryotic sequences. We identified and characterized TS homologs from five different sponge species isolated from geographically distant locations, thereby suggesting a broad distribution amongst sponges. This work sheds light on the role of sponges in secondary metabolite production and speaks to the possibility that other sponge-specific molecules originate from the animal host.


Asunto(s)
Productos Biológicos , Microbiota , Poríferos , Animales , Poríferos/genética , Organismos Acuáticos/genética , Microbiota/genética , Metagenoma , Filogenia
4.
Artículo en Inglés | MEDLINE | ID: mdl-38924775

RESUMEN

Rationale: Fibrotic hypersensitivity pneumonitis is a debilitating interstitial lung disease driven by incompletely understood immune mechanisms. Objectives: To elucidate immune aberrations in fibrotic hypersensitivity pneumonitis in single-cell resolution. Methods: Single-cell 5' RNA sequencing was conducted on peripheral blood mononuclear cells and bronchoalveolar lavage cells obtained from 45 patients with fibrotic hypersensitivity pneumonitis, 63 idiopathic pulmonary fibrosis, 4 non-fibrotic hypersensitivity pneumonitis, and 36 healthy controls in the United States and Mexico. Analyses included differential gene expression (Seurat), transcription factor activity imputation (DoRothEA-VIPER), and trajectory analyses (Monocle3/Velocyto-scVelo-CellRank). Measurements and Main Results: Overall, 501,534 peripheral blood mononuclear cells from 110 patients and controls and 88,336 bronchoalveolar lavage cells from 19 patients were profiled. Compared to controls, fibrotic hypersensitivity pneumonitis has elevated classical monocytes (adjusted-p=2.5e-3) and are enriched in CCL3hi/CCL4hi and S100Ahi classical monocytes (adjusted-p<2.2e-16). Trajectory analyses demonstrate that S100Ahi classical monocytes differentiate into SPP1hi lung macrophages associated with fibrosis. Compared to both controls and idiopathic pulmonary fibrosis, fibrotic hypersensitivity pneumonitis patient cells are significantly enriched in GZMhi cytotoxic T cells. These cells exhibit transcription factor activities indicative of TGFß and TNFα/NFκB pathways. These results are publicly available at https://ildimmunecellatlas.org. Conclusions: Single-cell transcriptomics of fibrotic hypersensitivity pneumonitis patients uncovered novel immune perturbations, including previously undescribed increases in GZMhi cytotoxic CD4+ and CD8+ T cells - reflecting this disease's unique inflammatory T-cell driven nature - as well as increased S100Ahi and CCL3hi/CCL4hi classical monocytes also observed in idiopathic pulmonary fibrosis. Both cell populations may guide the development of new biomarkers and therapeutic interventions.

5.
Proc Natl Acad Sci U S A ; 119(6)2022 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-35110408

RESUMEN

Domoic acid (DA), the causative agent of amnesic shellfish poisoning, is produced by select organisms within two distantly related algal clades: planktonic diatoms and red macroalgae. The biosynthetic pathway to isodomoic acid A was recently solved in the harmful algal bloom-forming diatom Pseudonitzschia multiseries, establishing the genetic basis for the global production of this potent neurotoxin. Herein, we sequenced the 507-Mb genome of Chondria armata, the red macroalgal seaweed from which DA was first isolated in the 1950s, identifying several copies of the red algal DA (rad) biosynthetic gene cluster. The rad genes are organized similarly to the diatom DA biosynthesis cluster in terms of gene synteny, including a cytochrome P450 (CYP450) enzyme critical to DA production that is notably absent in red algae that produce the simpler kainoid neurochemical, kainic acid. The biochemical characterization of the N-prenyltransferase (RadA) and kainoid synthase (RadC) enzymes support a slightly altered DA biosynthetic model in C. armata via the congener isodomoic acid B, with RadC behaving more like the homologous diatom enzyme despite higher amino acid similarity to red algal kainic acid synthesis enzymes. A phylogenetic analysis of the rad genes suggests unique origins for the red macroalgal and diatom genes in their respective hosts, with native eukaryotic CYP450 neofunctionalization combining with the horizontal gene transfer of N-prenyltransferases and kainoid synthases to establish DA production within the algal lineages.


Asunto(s)
Dimetilaliltranstransferasa/genética , Dimetilaliltranstransferasa/metabolismo , Ácido Kaínico/análogos & derivados , Neurotoxinas/metabolismo , Rhodophyta/metabolismo , Evolución Biológica , Vías Biosintéticas/genética , Diatomeas/genética , Diatomeas/metabolismo , Floraciones de Algas Nocivas/fisiología , Ácido Kaínico/metabolismo , Familia de Multigenes/genética , Neurotoxinas/genética , Filogenia , Intoxicación por Mariscos/metabolismo
6.
Proc Natl Acad Sci U S A ; 119(32): e2205360119, 2022 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-35930670

RESUMEN

Animal tissues comprise diverse cell types. However, the mechanisms controlling the number of each cell type within tissue compartments remain poorly understood. Here, we report that different cell types utilize distinct strategies to control population numbers. Proliferation of fibroblasts, stromal cells important for tissue integrity, is limited by space availability. In contrast, proliferation of macrophages, innate immune cells involved in defense, repair, and homeostasis, is constrained by growth factor availability. Examination of density-dependent gene expression in fibroblasts revealed that Hippo and TGF-ß target genes are both regulated by cell density. We found YAP1, the transcriptional coactivator of the Hippo signaling pathway, directly regulates expression of Csf1, the lineage-specific growth factor for macrophages, through an enhancer of Csf1 that is specifically active in fibroblasts. Activation of YAP1 in fibroblasts elevates Csf1 expression and is sufficient to increase the number of macrophages at steady state. Our data also suggest that expression programs in fibroblasts that change with density may result from sensing of mechanical force through actin-dependent mechanisms. Altogether, we demonstrate that two different modes of population control are connected and coordinated to regulate cell numbers of distinct cell types. Sensing of the tissue environment may serve as a general strategy to control tissue composition.


Asunto(s)
Proliferación Celular , Fibroblastos , Macrófagos , Animales , Recuento de Células , Fibroblastos/fisiología , Vía de Señalización Hippo , Macrófagos/citología , Macrófagos/fisiología , Factor de Crecimiento Transformador beta/metabolismo , Proteínas Señalizadoras YAP/metabolismo
7.
J Physiol ; 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39316014

RESUMEN

It remains unclear whether feedback from group III/IV muscle afferents is of continuous significance for regulating the pulmonary response during prolonged (>5 min), steady-state exercise. To elucidate the influence of these sensory neurons on hyperpnoea, gas exchange efficiency, arterial oxygenation and acid-base balance during prolonged locomotor exercise, 13 healthy participants (4 females; 21 (3) years, V ̇ O 2 max ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{max}}}}$ : 46 (8) ml/kg/min) performed consecutive constant-load cycling bouts at ∼50% (20 min), ∼75% (20 min) and ∼100% (5 min) of V ̇ O 2 max ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{max}}}}$ with intact (CTRL) and pharmacologically attenuated (lumbar intrathecal fentanyl; FENT) group III/IV muscle afferent feedback from the legs. Pulmonary responses were continuously recorded and arterial blood (radial catheter) periodically collected throughout the exercise. Pulmonary gas exchange efficiency was evaluated using the alveolar-arterial P O 2 ${{P}_{{{{\mathrm{O}}}_{\mathrm{2}}}}}$ difference ( A - a D O 2 ${\mathrm{A - a}}{{D}_{{{{\mathrm{O}}}_{\mathrm{2}}}}}$ ). There were no differences in any of the variables of interest between conditions before the start of the exercise. Pulmonary ventilation was up to 20% lower across all intensities during FENT compared to CTRL exercise (P < 0.001) and this hypoventilation was accompanied by an up to 10% lower arterial P O 2 ${{P}_{{{{\mathrm{O}}}_{\mathrm{2}}}}}$ and a 2-4 mmHg higher P C O 2 ${{P}_{{\mathrm{C}}{{{\mathrm{O}}}_{\mathrm{2}}}}}$ (both P < 0.001). The exercise-induced widening of A - a D O 2 ${\mathrm{A - a}}{{D}_{{{{\mathrm{O}}}_{\mathrm{2}}}}}$ was up to 25% larger during FENT compared to CTRL (P < 0.001). Importantly, the differences developed within the first minute of each stage and persisted, or further increased, throughout the remainder of each bout. These findings reflect a critical and time-independent significance of feedback from group III/IV leg muscle afferents for continuously regulating the ventilatory response, gas exchange efficiency, arterial oxygenation and acid-base balance during human locomotion. KEY POINTS: Feedback from group III/IV leg muscle afferents reflexly contributes to hyperpnoea during short duration (i.e. <5 min) locomotor exercise. Whether continuous feedback from these sensory neurons is obligatory to ensure adequate pulmonary responses during steady-state exercise of longer duration remains unknown. Lumbar intrathecal fentanyl was used to attenuate the central projection of group III/IV leg muscle afferents during prolonged locomotor exercise (i.e. 45 min) at intensities ranging from 50% to 100% of V ̇ O 2 max ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{max}}}}$ . Without affecting the metabolic rate, afferent blockade compromised pulmonary ventilation and gas exchange efficiency, consistently impairing arterial oxygenation and facilitating respiratory acidosis throughout exercise. These findings reflect the time-independent significance of feedback from group III/IV muscle afferents for regulating exercise hyperpnoea and gas exchange efficiency, and thus for optimizing arterial oxygenation and acid-base balance, during prolonged human locomotion.

8.
Antimicrob Agents Chemother ; 68(5): e0158723, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38534112

RESUMEN

AZD7442 is a combination of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-neutralizing antibodies, tixagevimab and cilgavimab, developed for pre-exposure prophylaxis (PrEP) and treatment of coronavirus disease 2019 (COVID-19). Using data from eight clinical trials, we describe a population pharmacokinetic (popPK) model of AZD7442 and show how modeling of "interim" data accelerated decision-making during the COVID-19 pandemic. The final model was a two-compartmental distribution model with first-order absorption and elimination, including standard allometric exponents for the effect of body weight on clearance and volume. Other covariates included were as follows: sex, age >65 years, body mass index ≥30 kg/m2, and diabetes on absorption rate; diabetes on clearance; Black race on central volume; and intramuscular (IM) injection site on bioavailability. Simulations indicated that IM injection site and body weight had > 20% effects on AZD7442 exposure, but no covariates were considered to have a clinically relevant impact requiring dose adjustment. The pharmacokinetics of AZD7442, cilgavimab, and tixagevimab were comparable and followed linear kinetics with extended half-lives (median 78.6 days for AZD7442), affording prolonged protection against susceptible SARS-CoV-2 variants. Comparison of popPK simulations based on "interim data" with a target concentration based on 80% viral inhibition and assuming 1.81% partitioning into the nasal lining fluid supported a decision to double the PrEP dosage from 300 mg to 600 mg to prolong protection against Omicron variants. Serum AZD7442 concentrations in adolescents weighing 40-95 kg were predicted to be only marginally different from those observed in adults, supporting authorization for use in adolescents before clinical data were available. In these cases, popPK modeling enabled accelerated clinical decision-making.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Tratamiento Farmacológico de COVID-19 , COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/efectos de los fármacos , Femenino , Masculino , Persona de Mediana Edad , Anticuerpos Monoclonales Humanizados/farmacocinética , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anciano , Adulto , COVID-19/prevención & control , Antivirales/farmacocinética , Antivirales/uso terapéutico , Adulto Joven , Adolescente , Anticuerpos Neutralizantes/sangre
9.
Eur Respir J ; 63(1)2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38212075

RESUMEN

The pleural lining of the thorax regulates local immunity, inflammation and repair. A variety of conditions, both benign and malignant, including pleural mesothelioma, can affect this tissue. A lack of knowledge concerning the mesothelial and stromal cells comprising the pleura has hampered the development of targeted therapies. Here, we present the first comprehensive single-cell transcriptomic atlas of the human parietal pleura and demonstrate its utility in elucidating pleural biology. We confirm the presence of known universal fibroblasts and describe novel, potentially pleural-specific, fibroblast subtypes. We also present transcriptomic characterisation of multiple in vitro models of benign and malignant mesothelial cells, and characterise these through comparison with in vivo transcriptomic data. While bulk pleural transcriptomes have been reported previously, this is the first study to provide resolution at the single-cell level. We expect our pleural cell atlas will prove invaluable to those studying pleural biology and disease. It has already enabled us to shed light on the transdifferentiation of mesothelial cells, allowing us to develop a simple method for prolonging mesothelial cell differentiation in vitro.


Asunto(s)
Mesotelioma Maligno , Mesotelioma , Neoplasias Pleurales , Humanos , Pleura/patología , Mesotelioma/genética , Mesotelioma/patología , Mesotelioma Maligno/patología , Neoplasias Pleurales/genética , Neoplasias Pleurales/patología , Perfilación de la Expresión Génica
10.
Artículo en Inglés | MEDLINE | ID: mdl-39133778

RESUMEN

Patients with hypertension (HTN) are characterized by exaggerated vascular resistance and mean arterial pressure (MAP), and a compromised leg blood flow (QL) response to exercise recruiting a small muscle mass. However, the impact of hypertension on peripheral hemodynamics and the development of neuromuscular fatigue during locomotor activities, which critically depends on QL, remain unknown. Eight HTN (143±11mmHg / 95±6mmHg; 45±13years) and 8 matched (age, activity) controls (120±6mmHg / 77±7mmHg; CTRL) performed constant-load cycling exercise at 25, 50, and 75W (for 4-min each), and at 165±41W (for 5-min). Exercise-induced locomotor muscle fatigue was quantified as the pre- to post-exercise change in quadriceps twitch-torque (∆Qtw, peripheral fatigue) and voluntary activation (∆VA%, central fatigue). QL (Doppler-ultrasound) and leg vascular conductance (LVC) were determined during cycling at 25, 50, and 75W. Heart Rate and ventilatory responses were recorded during all intensities. MAP during exercise was, on average, ~21mmHg higher (P=0.002) and LVC ~39% lower (P=0.001) in HTN compared to CTRL. QL was consistently between 20-30% lower (P=0.004) and heart rate was significantly higher in HTN. Exercise-induced peripheral (∆Qtw: -53±19% vs -25±23%) and central (∆VA%: -7±5% vs -3±2%) fatigue were significantly greater in HTN compared to CTRL. In addition to an exaggerated MAP, LVC and QL were lower during exercise in HTN compared to CTRL. Given the critical role of QL in determining the development of neuromuscular fatigue, these hemodynamic impairments likely accounted for the faster development of neuromuscular fatigue characterizing hypertensive individuals during locomotor exercise.

11.
J Viral Hepat ; 31(4): 216-218, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38235917

RESUMEN

The opioid crisis has adversely affected West Virginia's pregnant and infant populations. With high rates of opioid use disorder and neonatal abstinence syndrome, West Virginia has the highest rates of Hepatitis C (HCV) acute infection among pregnant women. To better understand how HCV impacts an already high-risk population, the study purpose was to (1) describe its prevalence among women receiving prenatal care at a single tertiary care clinic in Appalachia and compare with state and national rates, and (2) determine whether it is associated with preterm birth (gestation <37 weeks). Data were collected on a retrospective cohort of pregnant patients universally screened for HCV between 2017 and 2021. The study cohort had an HCV infection rate of 119/988 = 11.94% or 119.4 per 1000. This is five times the rate of 22.6 per 1000 live births in West Virginia in 2014 and 35 times the national rate of 3.4 per 1000 live births (MMWR Morb Mortal Wkly Rep 66, 2017 and 470). Viral loads were detected in 63 (6.38%) of patients. The study cohort with birth outcome data had high rates of tobacco use (326/720; 45.3%) and substance abuse (209/720; 29.0%). The preterm birth rate was 17.8% (128/720), almost double the national average (10.09%) (Natl Vital Stat Rep 70, 2021 and 1). There was no statistically significant difference in preterm birth between HCV-positive (15/92; 16.3%) and HCV-negative (113/628; 18.0%) patients. HCV infection in our population presents a significant public health issue and missed opportunity for treatment in a population with continuity of care challenges. These findings could be used to justify a pilot program for early postpartum referral for treatment.


Asunto(s)
Hepatitis C , Trastornos Relacionados con Opioides , Nacimiento Prematuro , Lactante , Embarazo , Recién Nacido , Femenino , Humanos , Nacimiento Prematuro/epidemiología , Mujeres Embarazadas , Prevalencia , Estudios Retrospectivos , Hepatitis C/epidemiología , Hepacivirus
12.
Phys Rev Lett ; 133(4): 042501, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39121400

RESUMEN

We investigated decays of ^{51,52,53}K at the ISOLDE Decay Station at CERN in order to understand the mechanism of the ß-delayed neutron-emission (ßn) process. The experiment quantified neutron and γ-ray emission paths for each precursor. We used this information to test the hypothesis, first formulated by Bohr in 1939, that neutrons in the ßn process originate from the structureless "compound nucleus." The data are consistent with this postulate for most of the observed decay paths. The agreement, however, is surprising because the compound-nucleus stage should not be achieved in the studied ß decay due to insufficient excitation energy and level densities in the neutron emitter. In the ^{53}K ßn decay, we found a preferential population of the first excited state in ^{52}Ca that contradicted Bohr's hypothesis. The latter was interpreted as evidence for direct neutron emission sensitive to the structure of the neutron-unbound state. We propose that the observed nonstatistical neutron emission proceeds through the coupling with nearby doorway states that have large neutron-emission probabilities. The appearance of "compound-nucleus" decay is caused by the aggregated small contributions of multiple doorway states at higher excitation energy.

13.
Exp Physiol ; 109(4): 535-548, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38180087

RESUMEN

The human spleen contracts in response to stress-induced catecholamine secretion, resulting in a temporary rise in haemoglobin concentration ([Hb]). Recent findings highlighted enhanced splenic response to exercise at high altitude in Sherpa, possibly due to a blunted splenic response to hypoxia. To explore the potential blunted splenic contraction in Sherpas at high altitude, we examined changes in spleen volume during hyperoxic breathing, comparing acclimatized Sherpa with acclimatized individuals of lowland ancestry. Our study included 14 non-Sherpa (7 female) residing at altitude for a mean continuous duration of 3 months and 46 Sherpa (24 female) with an average of 4 years altitude exposure. Participants underwent a hyperoxic breathing test at altitude (4300 m; barrometric pressure = âˆ¼430 torr; P O 2 ${P_{{{\mathrm{O}}_{\mathrm{2}}}}}$  = âˆ¼90 torr). Throughout the test, we measured spleen volume using ultrasonography and monitored oxygen saturation ( S p O 2 ${S_{{\mathrm{p}}{{\mathrm{O}}_{\mathrm{2}}}}}$ ). During rest, Sherpa exhibited larger spleens (226 ± 70 mL) compared to non-Sherpa (165 ± 34 mL; P < 0.001; effect size (ES) = 0.95, 95% CI: 0.3-1.6). In response to hyperoxia, non-Sherpa demonstrated 22 ± 12% increase in spleen size (35 ± 17 mL, 95% CI: 20.7-48.9; P < 0.001; ES = 1.8, 95% CI: 0.93-2.66), while spleen size remained unchanged in Sherpa (-2 ± 13 mL, 95% CI: -2.4 to 7.3; P = 0.640; ES = 0.18, 95% CI: -0.10 to 0.47). Our findings suggest that Sherpa and non-Sherpas of lowland ancestry exhibit distinct variations in spleen volume during hyperoxia at high altitude, potentially indicating two distinct splenic functions. In Sherpa, this phenomenon may signify a diminished splenic response to altitude-related hypoxia at rest, potentially contributing to enhanced splenic contractions during physical stress. Conversely, non-Sherpa experienced a transient increase in spleen size during hyperoxia, indicating an active tonic contraction, which may influence early altitude acclimatization in lowlanders by raising [Hb].


Asunto(s)
Mal de Altura , Hiperoxia , Humanos , Femenino , Altitud , Bazo , Aclimatación/fisiología , Hipoxia
14.
Langmuir ; 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39151025

RESUMEN

Aryl diazonium electrografting is a powerful method for imparting molecular functionality onto various substrates by forming a stable carbon-surface covalent bond. While the high reactivity of the aryl radical intermediate makes this method fast and reliable, it can also lead to the formation of an insulating and disordered multilayer film. These thick films affect electrochemical performance, especially for semiconductor substrates used in photoelectrochemical applications. We studied the effects of film thickness and composition by electrografting in situ-generated aminobenzene diazonium salts onto both n-type and p-type silicon electrodes at fixed potentials. Next, we attached ferrocene to the amine-terminated films and probed their (photo)electrochemical behavior. Cyclic voltammetry measurements showed decreased electrochemical reversibility with increasing diazonium film thickness; this reversibility was restored when ferrocene was incorporated throughout the film with a layer-by-layer deposition process. Finally, we compared the behavior of dark p-type electrodes to n-type photoelectrodes and observed differences in the electrochemical reversibility that we attribute to the change in potential drop across the two interfaces.

15.
J Surg Res ; 300: 173-182, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38815516

RESUMEN

INTRODUCTION: Intraoperative goal-directed hemodynamic therapy (GDHT) is a cornerstone of enhanced recovery protocols. We hypothesized that use of an advanced noninvasive intraoperative hemodynamic monitoring system to guide GDHT may decrease intraoperative hypotension (IOH) and improve perfusion during pancreatic resection. METHODS: The monitor uses machine learning to produce the Hypotension Prediction Index to predict hypotensive episodes. A clinical decision-making algorithm uses the Hypotension Prediction Index and hemodynamic data to guide intraoperative fluid versus pressor management. Pre-implementation (PRE), patients were placed on the monitor and managed per usual. Post-implementation (POST), anesthesia teams were educated on the algorithm and asked to use the GDHT guidelines. Hemodynamic data points were collected every 20 s (8942 PRE and 26,638 POST measurements). We compared IOH (mean arterial pressure <65 mmHg), cardiac index >2, and stroke volume variation <12 between the two groups. RESULTS: 10 patients were in the PRE and 24 in the POST groups. In the POST group, there were fewer minimally invasive resections (4.2% versus 30.0%, P = 0.07), more pancreaticoduodenectomies (75.0% versus 20.0%, P < 0.01), and longer operative times (329.0 + 108.2 min versus 225.1 + 92.8 min, P = 0.01). After implementation, hemodynamic parameters improved. There was a 33.3% reduction in IOH (5.2% ± 0.1% versus 7.8% ± 0.3%, P < 0.01, a 31.6% increase in cardiac index >2.0 (83.7% + 0.2% versus 63.6% + 0.5%, P < 0.01), and a 37.6% increase in stroke volume variation <12 (73.2% + 0.3% versus 53.2% + 0.5%, P < 0.01). CONCLUSIONS: Advanced intraoperative hemodynamic monitoring to predict IOH combined with a clinical decision-making tree for GDHT may improve intraoperative hemodynamic parameters during pancreatectomy. This warrants further investigation in larger studies.


Asunto(s)
Hemodinámica , Hipotensión , Monitoreo Intraoperatorio , Pancreatectomía , Humanos , Proyectos Piloto , Pancreatectomía/efectos adversos , Persona de Mediana Edad , Femenino , Masculino , Anciano , Hipotensión/prevención & control , Hipotensión/etiología , Hipotensión/diagnóstico , Monitoreo Intraoperatorio/métodos , Complicaciones Intraoperatorias/prevención & control , Complicaciones Intraoperatorias/etiología , Complicaciones Intraoperatorias/epidemiología , Monitorización Hemodinámica/métodos , Adulto , Algoritmos , Fluidoterapia/métodos , Toma de Decisiones Clínicas/métodos
16.
Pharmacoepidemiol Drug Saf ; 33(6): e5801, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38798093

RESUMEN

PURPOSE: Antiretrovirals (ARVs) are life-saving drugs used for the treatment and prevention of HIV infection and antiviral drugs (AVs) for the treatment of chronic HBV infection. ARVs have proven highly effective in reducing perinatal HIV transmission, however the risk of birth defects from prenatal exposure to ARVs/AVs is an ongoing concern. The Antiretroviral Pregnancy Registry (APR), an international, prospective exposure-registration cohort study, monitors ARV and AV use in pregnancy for early signals of teratogenicity. This communication reports results of 30-years' experience of ARV/AV exposure during pregnancy and lessons learned through continuous quality improvement. METHODS AND RESULTS: Birth defect prevalence is estimated and compared to internal and external groups. Statistical inference is based on exact methods for binomial proportions. Between 2006 and 2023, cumulative enrollment more than tripled from 6893 to 25 960 pregnancies and ARVs/AVs monitored increased from 29 to 222. Through January 2023, there were 21 636 live births and 631 outcomes with birth defects, for overall prevalence of 2.9/100 live births (95% CI 2.7, 3.2). The birth defect prevalence was 3.0% (95% CI 2.7%, 3.3%) among first trimester exposures and 2.8% (95% CI 2.5%, 3.2%) among second/third trimester exposures (prevalence ratio 1.04 [95% CI 0.89, 1.21]). CONCLUSIONS: Birth defect prevalence is not statistically significantly different between first trimester ARV/AV pregnancy exposures compared to second/third trimester exposures and is also not different from two population-based surveillance systems: 2.72/100 live births reported in the Metropolitan Atlanta Congenital Defects Program (MACDP); and 4.17/100 live births from the Texas Birth Defects Registry (TBDR).


Asunto(s)
Anomalías Inducidas por Medicamentos , Infecciones por VIH , Complicaciones Infecciosas del Embarazo , Sistema de Registros , Humanos , Embarazo , Femenino , Estudios Prospectivos , Anomalías Inducidas por Medicamentos/epidemiología , Anomalías Inducidas por Medicamentos/etiología , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Complicaciones Infecciosas del Embarazo/epidemiología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Adulto , Prevalencia , Recién Nacido , Antirretrovirales/uso terapéutico , Fármacos Anti-VIH/efectos adversos , Fármacos Anti-VIH/uso terapéutico , Antivirales/efectos adversos , Antivirales/uso terapéutico , Adulto Joven , Anomalías Congénitas/epidemiología , Estudios de Cohortes
17.
Support Care Cancer ; 32(6): 362, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38755329

RESUMEN

OBJECTIVES: To describe patients' and surrogate information seekers' experiences talking to clinicians about online cancer information. To assess the impact of clinicians telling patients or surrogate seekers not to search for information online. DESIGN: Cross-sectional survey. SAMPLE: A total of 282 participants, including 185 individuals with cancer and 97 surrogate seekers. METHODS: Individuals were recruited through a broad consent registry and completed a 20-min survey. FINDINGS: Cancer patients and surrogate seekers did not differ significantly in their experiences talking with clinicians about online cancer information. Nearly all patients and surrogate seekers who were told by a clinician not to go online for cancer information did so anyway. IMPLICATIONS: Interventions for improving cancer information seeking and communication with clinicians should target both patients and surrogate seekers. Clinicians should be educated about effective ways to communicate with patients and surrogate seekers about online cancer information.


Asunto(s)
Comunicación , Internet , Neoplasias , Humanos , Neoplasias/psicología , Estudios Transversales , Femenino , Masculino , Persona de Mediana Edad , Adulto , Anciano , Conducta en la Búsqueda de Información , Relaciones Médico-Paciente , Adulto Joven
18.
Clin Radiol ; 79(2): 117-123, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37989667

RESUMEN

AIM: To evaluate variation in magnetic resonance imaging (MRI) technique and reporting of rectal cancer staging examinations across the UK. MATERIALS AND METHODS: A retrospective, multi-centre audit was undertaken of imaging protocols and information documented within consecutive MRI rectal cancer reports between March 2020 and August 2021, which were compared against American and European guidelines. Inclusion criteria included histologically proven rectal adenocarcinoma and baseline staging MRI rectum only. RESULTS: Fully anonymised data from 924 MRI reports by 78 radiologists at 24 centres were evaluated. Thirty-two per cent of radiologists used template reporting, but these reports offered superior documentation of 13 out of 18 key tumour features compared to free-text reports including T-stage, relation to peritoneal reflection and mesorectal fascia (MRF), nodal status, and presence of extramural venous invasion (EMVI; p<0.027 in each). There was no significant differences in the remaining five features. Across all tumour locations, the tumour relationship to the MRF, the presence of EMVI, and the presence of tumour deposits were reported in 79.5%, 85.6%, and 44% of cases, respectively, and tumour, nodal, and distant metastatic stage documented in 94.4%, 97.7%, and 78.3%. In low rectal tumours, the relationship to the anal sphincter complex was reported in only 54.6%. CONCLUSION: Considerable variation exists in rectal cancer MRI acquisition and reporting in this sample of UK centres. Inclusion of key radiological features in reports must be improved for risk stratification and treatment decisions. Template reporting is superior to free-text reporting. Routine adoption of standardised radiology practices should now be considered to improve standards to facilitate personalised precision treatment for patients to improve outcomes.


Asunto(s)
Radiología , Neoplasias del Recto , Humanos , Estudios Retrospectivos , Neoplasias del Recto/patología , Imagen por Resonancia Magnética/métodos , Reino Unido , Estadificación de Neoplasias , Invasividad Neoplásica/patología
19.
Clin Radiol ; 2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39327208

RESUMEN

BACKGROUND: In the recent years, there has been an increase in the medical education literature showing that there are barriers to postgraduate exam success for some trainee groups compared to others. To date, there is little published data on whether these differences exist in UK radiology training. In this longitudinal cohort study, we aimed to evaluate the relationship between demographic and socioeconomic factors with Fellowship of the Royal College of Radiologists (FRCR) exam outcomes. MATERIALS AND METHODS: A longitudinal retrospective cohort study of UK radiology trainees attempting the FRCR Part 1 examination between 2014 and 2021 (n=1,860), with linked socioeconomic, demographic, and FRCR 2A and 2B results, was conducted. Chi-square tests assessed univariate associations between age, gender, ethnicity, and socioeconomic variables, with outcomes at each exam. Multivariate logistic regression analyses examined likelihood of FRCR success after adjusting for other variables. RESULTS: Among Part 1 candidates, 79.3% (1,465/1,850) passed at first attempt. Of these, 63.7% (600/940) subsequently passed 2A, and 77.2% (480/625) passed 2B. Significant associations with FRCR outcomes were seen with gender, ethnicity, and age (p < .005). Among socioeconomic variables, associations with FRCR outcomes were seen with parental education level, free school-meals, state-funded school (<.0.05 for Part 2A), and index of multiple deprivation (<0.05 for Part 1 and 2A). After adjusting for demographic factors, socioeconomic factors were not independently associated with exam success. CONCLUSION: Our study demonstrates that significant group-level differences exist at the FRCR examinations for candidates with protected characteristics (gender, ethnicity, and age) and other socioeconomic factors. These can act as barriers to career progression and may warrant interventions to support these groups.

20.
Nephrology (Carlton) ; 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39379170

RESUMEN

Exploration of the incidence and outcomes of Acute Kidney Injury (AKI) broadly, and sepsis associated AKI specifically, in Aboriginal and Torres Strait Islander (First Nations) people has been limited. We compared a nested cohort of First Nations people drawn from a multinational randomised controlled trial of hydrocortisone in septic shock, to a cohort matched for age, sex and severity of illness. Acute Kidney Injury was defined using the Kidney Disease Improving Global Outcomes (KDIGO) criteria, as well as incident use of kidney replacement therapy (KRT). Major Adverse Kidney Events (MAKE) were described as the composite of death, new dialysis requirement or persisting kidney dysfunction at hospital discharge. A cohort of 57 Aboriginal and/or Torres Strait Islander patients with septic shock was identified. 91.2% (52) of the First Nations cohort met KDIGO criteria for Stage 1 AKI or greater and 63% (36) met Stage 3 criteria. 59.6% (34) of the First Nations required dialysis as compared to 45.6% (26) in the matched cohort. 60.7% (34) of First Nations participants met criteria for MAKE at hospital discharge. The proportions requiring dialysis at 6, 12 and 24 months were 8.3%, 9.1% and 6.9% respectively. The incidences of AKI and MAKE reported in this First Nations cohort are substantially higher than in previously published cohorts of patients with sepsis, even those that use sensitive definitions of AKI. Measures to promote better management of infectious diseases in First Nations communities are required.

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