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1.
JACC Adv ; 3(3): 100780, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38938844

RESUMEN

Background: Clinical trials suggest that therapeutic-dose heparin may prevent critical illness and vascular complications due to COVID-19, but knowledge gaps exist regarding the efficacy of therapeutic heparin including its comparative effect relative to intermediate-dose anticoagulation. Objectives: The authors performed 2 complementary secondary analyses of a completed randomized clinical trial: 1) a prespecified per-protocol analysis; and 2) an exploratory dose-based analysis to compare the effect of therapeutic-dose heparin with low- and intermediate-dose heparin. Methods: Patients who received initial anticoagulation dosed consistently with randomization were included. The primary outcome was organ support-free days (OSFDs), a combination of in-hospital death and days free of organ support through day 21. Results: Among 2,860 participants, 1,761 (92.8%) noncritically ill and 857 (89.1%) critically ill patients were treated per-protocol. Among noncritically ill per-protocol patients, the posterior probability that therapeutic-dose heparin improved OSFDs as compared with usual care was 99.3% (median adjusted OR: 1.36; 95% credible interval [CrI]: 1.07-1.74). Therapeutic heparin had a high posterior probability of efficacy relative to both low- (94.6%; adjusted OR: 1.26; 95% CrI: 0.95-1.64) and intermediate- (99.8%; adjusted OR: 1.80; 95% CrI: 1.22-2.62) dose thromboprophylaxis. Among critically ill per-protocol patients, the posterior probability that therapeutic heparin improved outcomes was low. Conclusions: Among noncritically ill patients hospitalized for COVID-19 who were randomized to and initially received therapeutic-dose anticoagulation, heparin, compared with usual care, was associated with improved OSFDs, a combination of in-hospital death and days free of organ support. Therapeutic heparin appeared superior to both low- and intermediate-dose thromboprophylaxis.

2.
Dig Dis Sci ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38940974

RESUMEN

BACKGROUND AND AIMS: Drainage of pancreatic fluid collections (PFCs) is required in select cases including infected or symptomatic collections. In this network meta-analysis, we have compared lumen-apposing metal stents (LAMS), fully covered self-expandable metal stents (FCSEMS), and double-pigtail stents (DPS) to identify the most useful stent type in the management of PFCs. METHODS: We reviewed several databases to identify studies that compared DPS or FCSEMS with LAMS and the ones which compared DPS with FCSEMS for the treatment of PFCs. Our outcomes of interest were clinical success, adverse events, technical success, recurrence of PFCs, and procedure duration. Random effects model and frequentist approach were used for statistical analysis. RESULTS: We included 28 studies with 2974 patients. Rate of clinical success was significantly lower with DPS compared to LAMS, OR (95% CI): 0.43 (0.32, 0.59). Rate of recurrence was higher with DPS compared to LAMS, OR (95% CI): 2.06 (1.19, 3.57). We found no significant difference in rate of adverse events between groups. Rate of technical success was higher for FCSEMS compared to LAMS. Procedure duration was significantly shorter for LAMS compared to DPS and FCSEMS. Based on frequentist approach, LAMS was found to be superior to DPS and FCSEMS in achieving higher clinical success, lower rate of adverse events and recurrence, and shorter procedure time. CONCLUSIONS: This network meta-analysis demonstrates the superiority of LAMS over DPS and FCSEMS in the management of PFCs in achieving a higher clinical success, shorter procedure time, and lower rate of recurrence. Some of the analyses are not adequately powered to make firm conclusions, and future large multicenter RCTs are required to further evaluate this issue.

3.
Sci Rep ; 14(1): 13874, 2024 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-38880815

RESUMEN

In this paper, a multi-functional metasurface is proposed, which can work as a narrowband transmissive/reflective frequency selective surface (FSS) and an on-air frequency mixer based on its switching response. The metasurface is made up of unit cells with square and circular metallic loops connected by PIN diodes controlled by a bias source. In contrast to typical wideband FSSs, the structure provides 0.55 GHz of narrow stopband (a fractional bandwidth of 22%) at 2 GHz in the OFF state bias. The bandstop response can be adjusted by varying the reverse bias voltage. The metasurface alternates between its functionalities when in forward bias by providing a passband at the operational frequency. The structure is compact and operates as a transmissive/reflective surface under two different bias conditions (ON and OFF). The design is angularly stable and polarization-insensitive for both TE and TM polarisation. A prototype of the designed structure is developed and the measured results correlate well with the simulated responses from the finite-difference time-domain (FDTD) method-based simulation of the circuit model. On-air frequency mixing for a wave propagating through the metasurface is demonstrated and the effects of different parameters affecting the mixing are parametrically studied through FDTD simulations and experiments.

4.
Endosc Int Open ; 12(6): E740-E749, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38847015

RESUMEN

Background and study aims Endoscopic ultrasound (EUS)-guided transmural (TM) deployment of lumen-apposing metal stents (LAMS) is considered relatively safe in non-cirrhotic patients and is cautiously offered to cirrhotic patients. Patients and methods This was a retrospective, multicenter, international matched case-control study to study the safety of EUS-guided TM deployment of LAMS in cirrhotic patients. Results Forty-three cirrhotic patients with model for end-stage liver disease score 12.5 ± 5, with 23 having ascites and 16 with varices underwent EUS-guided TM LAMS deployment, including 19 for pancreatic fluid collection (PFC) drainage, 13 gallbladder drainage, six for endoscopic ultrasound-directed transgastric endoscopic retrograde cholangiopancreatography (ERCP), three for EDGI, one for endoscopic ultrasound-directed transenteric ERCP, and one postsurgical collection drainage. Technical failure occurred in one LAMS for PFC drainage. Clinical failure was encountered in another PFC. Nine adverse events (AEs) occurred. The most common AE was LAMS migration (3), followed by non-bleeding mucosal erosion (2), delayed bleeding (2), sepsis (1), and anesthesia-related complication (pulseless electrical activity) (1). Most AEs were graded as mild (6), followed by severe (2), and moderate (1); the majority were managed conservatively. On univariable comparison, risk of AE was higher when using a 20 × 10 mm LAMS and the absence of through-the-LAMS plastic stent(s). Conditional logistic regression of matched case-control patients did not show any association between potential predicting factors and occurrence of AEs. Conclusions Our study demonstrated that mainly in patients with Child-Pugh scores A and B cirrhosis and despite the presence of mild-to-moderate ascites in over half of cases, the majority of AEs were mild and could be managed conservatively. Further studies are warranted to verify the safety of LAMS in cirrhotic patients.

5.
Transfus Med ; 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38945170

RESUMEN

BACKGROUND AND OBJECTIVES: Regulatory requirement of fixed holding time (6 h) of whole blood (WB) at room temperature, that is, 22-24°C (RT) results in sub-optimal component separation. The aim was to evaluate the platelet concentrates (PC) prepared by both platelet rich plasma (PRP) and buffy coat (BC) methods after overnight hold (18-24 h) at RT. MATERIALS AND METHODS: A prospective experimental study was performed. A total of 48 WB units collected were divided into four groups (12 each) control-1 (C1) and test-1 (T1) for PRP and control-2 (C2) and test-2 (T2) for the BC method. Control groups were processed within 6 h, and in test groups, components were prepared after overnight hold, followed by evaluation of quality parameters. RESULTS: Irrespective of the method used, all PCs had similar volume, platelet yield, swirling, no bacterial contamination, RBC contamination, PaO2 and PaCO2 levels. PCs in the T1 group had significant differences in glucose and MPV values on d1, which were resolved by d5 of storage. PCs in T2 has significant differences in pH, glucose, and MPV levels throughout storage. PRBC in test and control groups had similar quality parameters till d42 of storage. FFPs in all tests were noninferior to the concurrent control groups till 3 months of storage. CONCLUSION: Overnight holding of WB had no lasting deleterious changes. Though a few biochemical parameters in the test groups were significantly different, they can be accepted to improve the logistics of component separation. Overall PRP method seemed to have a better result than the BC method after an overnight hold.

6.
Front Microbiol ; 15: 1342573, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38694802

RESUMEN

Introduction: Control of Campylobacter from farm to fork is challenging due to the frequent emergence of antimicrobial-resistant isolates. Furthermore, poultry production systems are known reservoirs of Campylobacter. The twin-arginine translocation (Tat) pathway is a crucial bacterial secretion system that allows Campylobacter to colonize the host intestinal tract by using formate as the main source of energy. However, Tat pathway is also a major contributing factor for resistance to copper sulfate (CuSO4). Methods: Since mammals and chickens do not have proteins or receptors that are homologous to bacterial Tat proteins, identification of small molecule (SM) inhibitors targeting the Tat system would allow the development of safe and effective control methods to mitigate Campylobacter in infected or colonized hosts in both pre-harvest and post-harvest. In this study, we screened 11 commercial libraries (n = 50,917 SM) for increased susceptibility to CuSO4 (1 mM) in C. jejuni 81-176, a human isolate which is widely studied. Results: Furthermore, we evaluated 177 SM hits (2.5 µg/mL and above) that increased the susceptibility to CuSO4 for the inhibition of formate dehydrogenase (Fdh) activity, a Tat-dependent substrate. Eight Tat-dependent inhibitors (T1-T8) were selected for further studies. These selected eight Tat inhibitors cleared all tested Campylobacter strains (n = 12) at >10 ng/mL in the presence of 0.5 mM CuSO4in vitro. These selected SMs were non-toxic to colon epithelial (Caco-2) cells when treated with 50 µg/mL for 24 h and completely cleared intracellular C. jejuni cells when treated with 0.63 µg/mL of SM for 24 h in the presence of 0.5 mM of CuSO4. Furthermore, 3 and 5-week-old chicks treated with SM candidates for 5 days had significantly decreased cecal colonization (up to 1.2 log; p < 0.01) with minimal disruption of microbiota. In silico analyses predicted that T7 has better drug-like properties than T2 inhibitor and might target a key amino acid residue (glutamine 165), which is located in the hydrophobic core of TatC protein. Discussion: Thus, we have identified novel SM inhibitors of the Tat pathway, which represent a potential strategy to control C. jejuni spread on farms.

7.
Artículo en Inglés | MEDLINE | ID: mdl-38715761

RESUMEN

Blockchain technology has become crucial in improving the privacy and security of enterprise applications in the cyber world. However, scalability has become a significant concern for researchers in large organizations, especially those with complex hierarchies and access privileges. As a result, the existing models and consensus algorithms suffer from various issues. Medical centers and healthcare providers are particularly affected by this problem due to the vast amount of data, making it a critical weakness of traditional database management systems. To address this issue, the authors propose a hierarchical model within the Hyperledger Fabric enterprise application, focusing on the healthcare sector as a use case. This model includes multiple organizations at different levels of the hierarchy, such as hospitals, hospital governance, and insurance companies. The initial implementation of this model includes two levels of hierarchy, demonstrating networks of hospitals joining an insurance company. The primary objective of the experiment is to test and improve the network's performance using this model. The model's performance is evaluated by manipulating and scaling environmental factors such as the number of organizations, transaction numbers, channels, block intervals, and block sizes. The benchmarking tool used for this assessment is Hyperledger Caliper, which measures indicators such as success and failure rates, throughput, and latency. Currently, the research focuses only on testing the model's scalability using patient data.

8.
Front Pain Res (Lausanne) ; 5: 1376506, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38808005

RESUMEN

Background and objectives: Post-acute COVID-19 syndrome or "long COVID" affects patients even after the recovery from Covid infection in various ways. Persistent headache or New Daily Persistent Headache (NDPH) is one of such symptoms. In this review, we will discuss about the case-reports of post covid-19 headache- NDPH phenotype both after and in the course of COVID-19 infection. Methods: Case reports/studies talked about patients having NDPH around the disease either immediately or late post COVID were included. Data was taken from the source and synthesised on a qualitative basis. Results: Literature search showed 3,538 articles, out of which 12 were screened as per the eligibility criteria and finally, 4 case reports on NDPH and Covid-19 were chosen for analysis from the database and by human search. All case reports justify the criteria for acceptability in quality for this systematic review. Conclusion: NDPH in and around Covid 19 infection is something that is currently an ingenious debated topic in the scientific community. More case studies should be written and published on the same subject so that a large systematic review could be conducted. Trial Registration Information: The review is registered in Prospero with no. Identifier (CRD42022354912). Systematic Review Registration: https://www.crd.york.ac.uk/, PROSPERO (CRD42022354912).

10.
Heliyon ; 10(7): e28557, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38596128

RESUMEN

Background: Post-stroke pain is common after a stroke and might be underreported. We describe Persistent Facial Pain (PFP) developed in post-stroke patients. Method: ology: This was a prospective hospital-based cohort study of stroke patients, and patients were followed up. Out of 415 stroke patients, 26 developed PFP. Result: Out of all PFP patients, six patients had an ischemic stroke, and 20 had a hemorrhagic stroke. 57.7% of patients had hypertension, while 34.6 patients had diabetes. The stroke location was left-sided in 12 patients and right-sided in 14 patients. 46.15% of patients responded to venlafaxine, 30.77% responded to amitriptyline, and 23.08% responded to pregabalin. Conclusion: Persistent facial pain is a pain syndrome that might be missed in patients post-stroke. It might be more common in hemorrhagic stroke patients than in ischemic stroke patients. It responds adequately to antidepressants. A high index of suspicion is required to diagnose and appropriately manage these patients.

11.
J Clin Neurosci ; 123: 130-136, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38574684

RESUMEN

BACKGROUND: Aphasia is a language disorder acquired secondary to brain damage. This study aims to evaluate clinical and radiological profile of patients with post stroke aphasia and factors affecting its recovery. METHODS: We conducted a prospective study of patients with first left Middle or Anterior Cerebral Artery infarct or Intracerebral Hemorrhage (ICH) with aphasia admitted within 14 days of stroke onset. Aphasia Quotient (AQ) was assessed at 2 weeks (AQ1) and 3 months (AQ2) using Western Aphasia Battery-Hindi version. Magnetic Resonance Imaging of brain with Diffusion Tensor Imaging (DTI) of bilateral Arcuate Fasciculus (AF) and Corticospinal Tract was done at admission, and stroke volume, Laterality Indices of Fractional Anisotropy (LI-FA), Mean Diffusivity (LI-MD), Radial Diffusivity (LI-RD), Axial Diffusivity (LI-AD) and Apparent Diffusion Coefficient (LI-ADC) were obtained. RESULTS: 36 patients [8 ICH and 28 Acute Ischemic Stroke (AIS)] were included. AQ1 and AQ2 were significantly higher in subcortical stroke than cortical. AQ2 and increase in AQ scores (including its subscores) were significantly higher in ICH than AIS. National Institutes of Health Stroke Scale score at admission and volume of stroke had significant negative correlation with AQ1 and AQ2. Laterality Index of Fractional Anisotropy of Arcuate Fasciculus [LI-FA (AF)] had significant positive correlation with AQ2 and naming score at 3 months. Laterality Index of Mean Diffusivity of Arcuate Fasciculus [LI-MD (AF)] had significant negative correlation with AQ1, AQ2 and all subcomponents of AQ2. Significant positive correlation was seen between improvements in Modified Rankin Scale score and AQ. CONCLUSION: The study shows that DTI can be used to predict severity of aphasia at follow up and recovery in language and motor functions occur in parallel.


Asunto(s)
Afasia , Imagen de Difusión Tensora , Accidente Cerebrovascular , Humanos , Masculino , Femenino , Persona de Mediana Edad , Afasia/etiología , Afasia/diagnóstico por imagen , Estudios Prospectivos , India , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen , Anciano , Estudios de Seguimiento , Adulto , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Recuperación de la Función/fisiología
12.
Sci Rep ; 14(1): 9342, 2024 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-38653763

RESUMEN

Chickpea is a highly nutritious protein-rich source and one of the major crops to alleviate global malnutrition, but poor seed quality affects its productivity. Seed quality is essential for better crop establishment and higher yields, particularly in the uncertain climate change. The present study investigated the impact of botanical priming versus hydropriming and bavistin seed treatment on chickpea seeds. A detailed physiological (germination percentage, root and shoot length, vigour index) and biochemical (amylase, protease, dehydrogenase, phytase, and lipid peroxidation) analysis was carried out in order to assess the effect of priming treatments. Turmeric-primed seeds showed better germination rate (94.5%), seedling length, enzyme activity, and lower malondialdehyde (MDA) content. Sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis revealed the expression of minor polypeptides of albumin and globulin in the primed seeds. Moreover, field experiments indicated increased crop growth, vigour, days to 50% flowering, yield and its attributing traits in turmeric-primed seeds. Botanical priming can increase chickpea yield by up to 16% over the control group. This low-cost and eco-friendly technique enhances seed and crop performance, making it a powerful tool for augmenting chickpea growth. Therefore, chickpea growers must adopt botanical priming techniques to enhance the quality of seed and crop performance. Moreover, this approach is environmentally sustainable and can help conserve natural resources in the long term. Therefore, this new approach must be widely adopted across the agricultural industry to ensure sustainable and profitable farming practices.


Asunto(s)
Cicer , Productos Agrícolas , Germinación , Semillas , Cicer/crecimiento & desarrollo , Cicer/efectos de los fármacos , Cicer/metabolismo , Semillas/crecimiento & desarrollo , Semillas/efectos de los fármacos , Semillas/metabolismo , Germinación/efectos de los fármacos , Productos Agrícolas/crecimiento & desarrollo , Productos Agrícolas/efectos de los fármacos , Plantones/crecimiento & desarrollo , Plantones/efectos de los fármacos , Plantones/metabolismo , Proteínas de Plantas/metabolismo , Malondialdehído/metabolismo
13.
Nat Struct Mol Biol ; 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38671230

RESUMEN

Human syncytin-1 and suppressyn are cellular proteins of retroviral origin involved in cell-cell fusion events to establish the maternal-fetal interface in the placenta. In cell culture, they restrict infections from members of the largest interference group of vertebrate retroviruses, and are regarded as host immunity factors expressed during development. At the core of the syncytin-1 and suppressyn functions are poorly understood mechanisms to recognize a common cellular receptor, the membrane transporter ASCT2. Here, we present cryo-electron microscopy structures of human ASCT2 in complexes with the receptor-binding domains of syncytin-1 and suppressyn. Despite their evolutionary divergence, the two placental proteins occupy similar positions in ASCT2, and are stabilized by the formation of a hybrid ß-sheet or 'clamp' with the receptor. Structural predictions of the receptor-binding domains of extant retroviruses indicate overlapping binding interfaces and clamping sites with ASCT2, revealing a competition mechanism between the placental proteins and the retroviruses. Our work uncovers a common ASCT2 recognition mechanism by a large group of endogenous and disease-causing retroviruses, and provides high-resolution views on how placental human proteins exert morphological and immunological functions.

14.
Gastrointest Endosc ; 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38431104

RESUMEN

BACKGROUND AND AIMS: Direct endoscopic necrosectomy (DEN) is a recommended strategy for treatment of walled-off-necrosis (WON). DEN uses a variety of devices including the EndoRotor (Interscope, Inc.) debridement catheter. Recently, a 5.1 mm EndoRotor with increased chamber size and rate of tissue removal was introduced. The aim of this study was to assess the efficacy and safety of this device. METHODS: A multi-center cohort study was conducted at eight institutions including patients who underwent DEN with the 5.1 mm EndoRotor. The primary outcome was the number of DEN sessions needed for WON resolution. Secondary outcomes included the average percent reduction in solid WON debris and decrease in WON area per session, total time spent performing EndoRotor therapy for WON resolution, and adverse events. RESULTS: 64 procedures in 41 patients were included. For patients in which the 5.1 mm EndoRotor catheter was the sole therapeutic modality, an average of 1.6 DEN sessions resulted in WON resolution with an average cumulative time of 85.5 minutes. Of the 21 procedures with data regarding percent of solid debris, the average reduction was 85% +/- 23% per session. Of the 19 procedures with data regarding WON area, the mean area significantly decreased from 97.6 +/- 72.0 cm2 to 27.1 +/- 35.5 cm2 (p<0.001) per session. Adverse events included two intra-procedural LAMS dislodgements managed endoscopically and three perforations none of which were related to EndoRotor. Bleeding was reported in seven cases, none required embolic or surgical therapy and two required blood transfusions. CONCLUSIONS: This is the first multi-center retrospective study to investigate the efficacy and safety of the 5.1 mm EndoRotor catheter for WON. Results from this study showed an average of 1.6 DEN sessions were needed to achieve WON resolution with an 85% single session reduction in solid debris and a 70% single session decrease in WON area with minimal adverse events.

15.
Cureus ; 16(2): e53918, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38465029

RESUMEN

INTRODUCTION: Lung cancer constitutes a critical global health concern. According to the International Agency for Research on Cancer's (IARC) GLOBOCAN 2020 estimates, lung cancer is the leading cause of death in cancer patients. In areas where tuberculosis is prevalent, misdiagnosis and mistreatment frequently result from overlap, creating significant difficulties that delay diagnosis and treatment. Amid this complication, bronchoscopic techniques emerge as critical diagnostic tools, though their efficacy varies between studies. METHOD: Our retrospective study, conducted from July 2021 to December 2022 at the Department of Respiratory Medicine, Ganesh Shankar Vidyarthi Memorial Medical College, Kanpur, examined 156 participants with malignancies. Our focus encompassed diverse lesions within the bronchial landscape, revealing intriguing findings. RESULTS: Bronchoscopic examinations unravelled prevalent abnormalities: 52 (33.3%) manifested as intraluminal growth, 48 (31.6%) as mucosal irregularities, and a less frequent (16, 10.3%) as an intraluminal bulge. Transbronchial needle aspiration stood out with a 10/11 (91%) positivity rate, biopsy came in second at 38/46 (83%), and bronchoalveolar lavage showed a 44/152 (29%) positivity rate. It was interesting to see how the lesions were spread out among the different types of histology. For example, squamous cell carcinoma showed 17/37 (46%) intraluminal growth, while adenocarcinoma showed 22/60 (36.7%) intraluminal growth and 4/60 (6.7%) intraluminal bulge. Moreover, a significant absence of abnormalities was observed in various lesions, underlining the intricacies of characterising bronchial lesions. CONCLUSION: Our study shows that direct tissue sampling is better and that new bronchoscopic technologies are important for diagnosing lesions that were hard to get to in the past. However, limitations in patient selection biases and the single-centre focus caution against generalised interpretations. Our research illuminates the pivotal role of bronchoscopic methods in diagnosing lung lesions, emphasising the necessity for continued advancements to enhance diagnostic accuracy and treatment efficacy in lung cancer subtypes.

16.
Microbiol Resour Announc ; 13(4): e0067723, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38488370

RESUMEN

We present the complete genome sequence of the probiotic strain Lactobacillus acidophilus ATCC 9224. The genome sequence provides a valuable resource for investigating the phylogenetic evolution of this lineage and conducting comparative genomics with other Lactobacillus strains and species.

17.
ACS Omega ; 9(5): 5193-5202, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38343928

RESUMEN

Managing and remediating perfluoroalkyl and polyfluoroalkyl substance (PFAS) contaminated sites remains challenging. The major reasons are the complexity of geological media, partly unknown dynamics of the PFAS in different phases and at fluid-fluid and fluid-solid interfaces, and the presence of cocontaminants such as nonaqueous phase liquids (NAPLs). Critical knowledge gaps exist in understanding the behavior and fate of PFAS in vadose and saturated zones and in other porous media such as concrete and asphalt. The complexity of PFAS-surface interactions warrants the use of advanced characterization and computational tools to understand and quantify nanoscale behavior of the molecules. This can then be upscaled to the microscale to develop a constitutive relationship, in particular to distinguish between surface and bulk diffusion. The dominance of surface diffusion compared to bulk diffusion results in the solutocapillary Marangoni effect, which has not been considered while investigating the fate of PFAS. Without a deep understanding of these phenomena, derivation of constitutive relationships is challenging. The current Darcy scale mass-transfer models use constitutive relationships derived from either experiments or field measurements, which makes their applicability potentially limited. Here we review current efforts and propose a roadmap for developing Darcy scale transport equations for PFAS. We find that this needs to be based on systematic upscaling of both experimental and computational studies from nano- to microscales. We highlight recent efforts to undertake molecular dynamics simulations on problems with similar levels of complexity and explore the feasibility of conducting nanoscale simulations on PFAS dynamics at the interface of fluid pairs.

18.
ACS Nano ; 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38335970

RESUMEN

Quantum emitters in solid-state crystals have recently attracted a great deal of attention due to their simple applicability in optical quantum technologies. The polarization of single photons generated by quantum emitters is one of the key parameters that plays a crucial role in various applications, such as quantum computation, which uses the indistinguishability of photons. However, the degree of single-photon polarization is typically quantified using the time-averaged photoluminescence intensity of single emitters, which provides limited information about the dipole properties in solids. In this work, we use single defects in hexagonal boron nitride and nanodiamond as efficient room-temperature single-photon sources to reveal the origin and temporal evolution of the dipole orientation in solid-state quantum emitters. The angles of the excitation and emission dipoles relative to the crystal axes were determined experimentally and then calculated using density functional theory, which resulted in characteristic angles for every specific defect that can be used as an efficient tool for defect identification and understanding their atomic structure. Moreover, the temporal polarization dynamics revealed a strongly modified linear polarization visibility that depends on the excited-state decay time of the individual excitation. This effect can potentially be traced back to the excitation of excess charges in the local crystal environment. Understanding such hidden time-dependent mechanisms can further improve the performance of polarization-sensitive experiments, particularly that for quantum communication with single-photon emitters.

19.
Crit Care ; 28(1): 63, 2024 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-38414082

RESUMEN

RATIONALE: Acute respiratory distress syndrome (ARDS) is a life-threatening critical care syndrome commonly associated with infections such as COVID-19, influenza, and bacterial pneumonia. Ongoing research aims to improve our understanding of ARDS, including its molecular mechanisms, individualized treatment options, and potential interventions to reduce inflammation and promote lung repair. OBJECTIVE: To map and compare metabolic phenotypes of different infectious causes of ARDS to better understand the metabolic pathways involved in the underlying pathogenesis. METHODS: We analyzed metabolic phenotypes of 3 ARDS cohorts caused by COVID-19, H1N1 influenza, and bacterial pneumonia compared to non-ARDS COVID-19-infected patients and ICU-ventilated controls. Targeted metabolomics was performed on plasma samples from a total of 150 patients using quantitative LC-MS/MS and DI-MS/MS analytical platforms. RESULTS: Distinct metabolic phenotypes were detected between different infectious causes of ARDS. There were metabolomics differences between ARDSs associated with COVID-19 and H1N1, which include metabolic pathways involving taurine and hypotaurine, pyruvate, TCA cycle metabolites, lysine, and glycerophospholipids. ARDSs associated with bacterial pneumonia and COVID-19 differed in the metabolism of D-glutamine and D-glutamate, arginine, proline, histidine, and pyruvate. The metabolic profile of COVID-19 ARDS (C19/A) patients admitted to the ICU differed from COVID-19 pneumonia (C19/P) patients who were not admitted to the ICU in metabolisms of phenylalanine, tryptophan, lysine, and tyrosine. Metabolomics analysis revealed significant differences between C19/A, H1N1/A, and PNA/A vs ICU-ventilated controls, reflecting potentially different disease mechanisms. CONCLUSION: Different metabolic phenotypes characterize ARDS associated with different viral and bacterial infections.


Asunto(s)
COVID-19 , Subtipo H1N1 del Virus de la Influenza A , Gripe Humana , Neumonía Bacteriana , Síndrome de Dificultad Respiratoria , Humanos , COVID-19/complicaciones , Gripe Humana/complicaciones , Gripe Humana/terapia , Espectrometría de Masas en Tándem , Cromatografía Liquida , Lisina , Síndrome de Dificultad Respiratoria/complicaciones , Síndrome de Dificultad Respiratoria/terapia , Piruvatos
20.
Surg Oncol ; 52: 102030, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38183855

RESUMEN

BACKGROUND: Fluorescence-guided surgery (FGS) is a novel technique to successfully assess surgical margins intraoperatively. Investigation and adoption of this technique in orthopaedic oncology remains limited. METHODS: The PRISMA guidelines were followed for this manuscript. Our study was registered on PROSPERO (380520). Studies describing the use of FGS for resection of bone and soft tissue sarcomas (STS) on humans were included. Diagnostic performance metrics (sensitivity, specificity, positive predictive value [PPV], negative predictive value [NPV] and accuracy) and margin positivity rate were the outcomes assessed. RESULTS: Critical appraisal using the Joanna Brigs Institute checklists showed significant concerns for study quality. Sensitivity of FGS ranged from 22.2 % to 100 % in three of the four studies assessing his metrics; one study in appendicular tumors in the pediatric population reported 0 % sensitivity in the three cases included. Specificity ranged from 9.38 % to 100 %. PPV ranged from 14.6 % to 70 % while NPV was between 53.3 % and 100 %. The diagnostic accuracy ranged from 21.62 % to 92.31 %. Margin positivity rate ranged from 2 % to 50 %, with six of the seven studies reporting values between 20 % and 50 %. CONCLUSIONS: FSG is a feasible technique to assess tumor margins in bone and STS. Reported performance metrics and margin positivity rates vary widely between studies due to low study quality and high heterogeneity in dying protocols. LEVEL OF EVIDENCE: Level III, diagnostic study.


Asunto(s)
Sarcoma , Neoplasias de los Tejidos Blandos , Cirugía Asistida por Computador , Humanos , Niño , Sarcoma/patología , Neoplasias de los Tejidos Blandos/diagnóstico , Neoplasias de los Tejidos Blandos/cirugía , Neoplasias de los Tejidos Blandos/patología , Valor Predictivo de las Pruebas , Cirugía Asistida por Computador/métodos
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