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1.
ACS ES T Eng ; 4(9): 2121-2134, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39296421

RESUMEN

Taste and odor are crucial factors in evaluating the quality of drinking water for consumers. Geosmin is an example of a pollutant commonly found in potable water responsible for earthy and musty taste, and odor even at low concentrations. We have investigated the use of a hybrid two-step adsorption-mineralization process for low-level volatile organic compounds removal from potable water using dielectric barrier discharge over common metal oxides (MO). The system proposed is a proof of principle with tert-butanol (TBA) used as a model compound for geosmin removal/degradation during wastewater treatment when combined with an appropriate metal oxide adsorbent. Initial assessments of the adsorption properties of titania by density functional theory (DFT) calculations and experimental tests indicated that the adsorption of geosmin and TBA with water present results in only weak interactions between the sorbate and the metal oxide. In contrast, the DFT results show that alumina could be a suitable adsorbent for these tertiary alcohols and were reinforced by experimental studies. We find that while there is a competitive effect between the water and TBA adsorption from gaseous/liquid feed, the VOC can be removed, and the alumina will be regenerated by the reactive oxygen species (ROS) produced by a dielectric barrier discharge (DBD). The use of alumina in conjunction with NTP leads to efficient degradation of the adsorbate and the formation of oxygenated intermediates (formates, carbonates, and carboxylate-type species), which could then be mineralized for the regeneration of the adsorbent. A reaction mechanism has been proposed based on the in-situ infrared measurements and DFT calculations, while the removal of TBA with conventional heating is indicative of a gradual desorption process as a function of temperature rather than the destruction of the adsorbate. Furthermore, steady performance was observed after several adsorption-regeneration cycles, indicating no alteration of the adsorption properties of alumina during the NTP treatment and demonstrating the potential of the approach to be applied in the treatment of high throughput of water, without the challenges faced by the biocatalysts or formation of toxic byproducts.

2.
Cereb Cortex ; 34(9)2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39315647

RESUMEN

While some studies have used a transdiagnostic approach to relate depression to metabolic or functional brain alterations, the structural substrate of depression across clinical diagnostic categories is underexplored. In a cross-sectional study of 52 patients with major depressive disorder and 51 with post-traumatic stress disorder, drug-naïve, and spanning mild to severe depression severity, we examined transdiagnostic depressive correlates with regional gray matter volume and the topological properties of gray matter-based networks. Locally, transdiagnostic depression severity correlated positively with gray matter volume in the right middle frontal gyrus and negatively with nodal topological properties of gray matter-based networks in the right amygdala. Globally, transdiagnostic depression severity correlated positively with normalized characteristic path length, a measure implying brain integration ability. Compared with 62 healthy control participants, both major depressive disorder and post-traumatic stress disorder patients showed altered nodal properties in regions of the fronto-limbic-striatal circuit, and global topological organization in major depressive disorder in particular was characterized by decreased integration and segregation. These findings provide evidence for a gray matter-based structural substrate underpinning depression, with the prefrontal-amygdala circuit a potential predictive marker for depressive symptoms across clinical diagnostic categories.


Asunto(s)
Amígdala del Cerebelo , Trastorno Depresivo Mayor , Sustancia Gris , Imagen por Resonancia Magnética , Corteza Prefrontal , Trastornos por Estrés Postraumático , Humanos , Masculino , Trastorno Depresivo Mayor/diagnóstico por imagen , Trastorno Depresivo Mayor/fisiopatología , Femenino , Trastornos por Estrés Postraumático/diagnóstico por imagen , Trastornos por Estrés Postraumático/fisiopatología , Trastornos por Estrés Postraumático/patología , Adulto , Corteza Prefrontal/diagnóstico por imagen , Corteza Prefrontal/patología , Amígdala del Cerebelo/diagnóstico por imagen , Amígdala del Cerebelo/patología , Imagen por Resonancia Magnética/métodos , Estudios Transversales , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Persona de Mediana Edad , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/patología , Índice de Severidad de la Enfermedad , Adulto Joven
3.
J Surg Educ ; 81(11): 1691-1698, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39303659

RESUMEN

OBJECTIVE: The American Board of Surgery In-Training Examination (ABSITE) is an important factor in general surgery resident career development. The use of practice question banks for ABSITE preparation improves exam scores and completing more practice questions results in higher scores. The objective of this study is to describe the design of a novel, team-based ABSITE competition implemented into our residency program and analyze its effect on exam performance. DESIGN: For the 2023 to 2024 academic year (AY), residents were randomly sorted into teams. The number of TrueLearn (TL) practice questions completed by each team during the 6-month period preceding the 2024 ABSITE was monitored at regular intervals. Paired sample t-test was used to compare total questions completed and ABSITE percent scores from the prior AY. Simple linear regression was performed to determine if total completed questions predicted ABSITE percent scores, and if the change in total completed questions predicted a change in ABSITE percent scores for unique residents. SETTING: University-affiliated general surgery residency program. PARTICIPANTS: About 34 clinical and research general surgery residents. RESULTS: Mean total TL questions completed per resident increased by 175.2, with a difference trending toward statistical significance (1037.9 ± 583.6 vs 1213.1 ± 596.0, p = 0.08). Mean ABSITE percent scores significantly increased by 4.6% (68.2 ± 8.7 vs 72.8 ± 5.7, p < 0.001). Total completed questions positively correlated with ABSITE percent scores (R2 = 0.21, F (1,66) = 17.04, p < 0.001). Among individual residents, completing more questions than the prior AY predicted improvement in ABSITE percent scores (R2 =.18, F (1,32) = 7.02, p = 0.01). Our model predicts that by completing 300 additional practice questions (e.g. 10 more questions/day for 1 month) a resident's ABSITE percent score will increase by 4.8 percentage points. CONCLUSION: Implementation of a team-based ABSITE competition is a straightforward and effective intervention that increases general surgery resident question bank utilization and significantly improves ABSITE percent scores.

4.
Transl Psychiatry ; 14(1): 384, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39304648

RESUMEN

Harm avoidance (HA) is a Cloninger personality trait that describes behavioural inhibition to avoid aversive stimuli. It serves as a predisposing factor that contributes to the development of mental disorders such as anxiety and major depressive disorder. Neuroimaging research has identified some brain anatomical and functional correlates of HA, but reported findings are inconsistent. We therefore conducted a multimodal meta-analysis of whole-brain structural and resting-state functional neuroimaging studies to identify the most stable neural substrate of HA. Included were a total of 10 structural voxel-based morphometry studies (11 datasets) and 13 functional positron emission tomography or single photon emission computed tomography studies (16 datasets) involving 3053 healthy participants without any psychiatric or neurological disorders evaluated for HA using the Three-Dimensional Personality Questionnaire (TPQ) or the Temperament and Character Inventory (TCI). The meta-analysis revealed brain volumetric correlates of HA in parietal and temporal cortices, and resting-state functional correlates in prefrontal, temporal and parietal gray matter. Volumetric and functional correlates co-occurred in the left superior frontal gyrus and left middle frontal gyrus, and were dissociated in the left rectus gyrus. Our meta-analysis is the first study to give a comprehensive picture of the structural and functional correlates of HA, a contribution that may help bridge the grievous gap between the neurobiology of HA and the pathogenesis, prevention and treatment of HA-related mental disorders.


Asunto(s)
Encéfalo , Neuroimagen Funcional , Reducción del Daño , Humanos , Encéfalo/diagnóstico por imagen , Tomografía de Emisión de Positrones , Imagen por Resonancia Magnética , Tomografía Computarizada de Emisión de Fotón Único , Personalidad/fisiología , Neuroimagen , Mapeo Encefálico
6.
J Biomech ; 176: 112309, 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39260233

RESUMEN

One of the main causes of implant failure and revision surgery in total hip replacement (THR) is aseptic loosening often caused by the accumulation of wear debris arising between the contact surfaces of the acetabular cup and femoral head during activities of daily living (ADL's). However, limited information is available regarding the contact force pathways between these two surfaces during specific ADL's. In this study, through musculoskeletal modelling, we aimed to estimate the orientation of the hip contact force pathway on the acetabular cup. One hundred and thirty-two THR patients underwent motion capture analysis whilst undertaking locomotor and non-locomotor ADL's. Musculoskeletal simulations were performed to calculate contact force pathways using inverse dynamics analysis. We then qualitatively compared differences in the contact force pathways between patients and between ADL's. Walking resulted in a typical figure-of-eight pattern, with the peak contact forces occurring in the superior-anterior area of the cup. The non-locomotive activities such as stand up, sit down and squat had a more linear shape, spanning across the superior-posterior quarter of the cup. Our results showed a large inter-patient variability in the shape and location of the contact force pathway. There is a distinct difference in the location and shape of the pathway between locomotor and non-locomotor activities and this could result in different wear accumulations. These results could enhance our understanding why revision rates vary across the population and could inform the development of personalised implant design.

7.
Nat Commun ; 15(1): 7837, 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39244602

RESUMEN

Alkoxycarbonylation reactions are common in the chemical industry, yet process sustainability is limited by the inefficient utilization of CO. In this study, we address this issue and demonstrate that significant improvements can be achieved by adopting a heterogeneously catalyzed process, using a Ru/NbOx catalyst. The Ru/NbOx catalyst enables the direct synthesis of methyl propionate, a key industrial commodity, with over 98% selectivity from CO, ethylene and methanol, without any ligands or acid/base promoters. Under ambient CO pressure, a high CO utilization efficiency (336 mmolestermolCO-1h-1) is achieved. Mechanistic investigations reveal that CO undergoes a methoxycarbonyl (COOCH3) intermediate pathway, attacking the terminal carbon atom of alkene and yielding linear esters. The origins of prevailing linear regioselectivity in esters are revealed. The infrared spectroscopic feature of the key COOCH3 species is observed at 1750 cm-1 (C=O vibration) both experimentally and computationally. The broad substrate applicability of Ru/NbOx catalyst for ester production is demonstrated. This process offers a sustainable and efficient approach with high CO utilization and atom economy for the synthesis of esters.

8.
Angew Chem Int Ed Engl ; : e202413073, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39269196

RESUMEN

A rationally designed dual purpose non-canonical amino acid (Trz) has been synthesised and successfully incorporated into a protein scaffold via genetic code expansion. Trz contains a 5-pyridyl-1,2,4-triazine system, which allows for inverse electron-demand Diels-Alder (IEDDA) reactions to occur on the triazine ring and for metal ions to be chelated both before and after the click reaction. Trz was successfully incorporated into a protein scaffold and the IEDDA utility of Trz demonstrated through the site-specific labelling of the purified protein with a bicyclononyne. Additionally, Trz was shown to successfully coordinate a cyclometallated iridium(III) centre, providing access to a bioorthogonal luminogenic probe. The luminescent properties of the Ir(III)-bound protein blue-shift upon IEDDA click reaction with bicyclononyne, providing a unique method for monitoring the extent and location of the labelling reaction. In summary, Trz is a new dual purpose non-canonical amino acid, which has great potential for myriad bioapplications where metal-based functionality is required, for example in imaging, catalysis, or photo-dynamic therapy, in conjunction with a bioorthogonal reactive handle to impart additional functionalities, such as dual modality imaging or therapeutic payloads.

9.
Surg Innov ; : 15533506241281316, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39218621

RESUMEN

BACKGROUND: Impaired visibility is a challenge in laparoscopic surgery. Frequent scope removal increases operative time, reduces efficiency, and potentially compromises patient safety. We examine our initial experience with a novel cleaning device that applies cold plasma to the scope lens and review current available laparoscope cleaning methods. METHODS: The novel device was used in a variety of laparoscopic general surgery cases from April to November 2023. Primary outcome was number of scope removals per case. Secondary outcomes were time spent cleaning and number of times the scope became smudged or dirty with blood/tissue debris (debris events). An existing device that utilizes heated anti-fogging solution was used for comparison. RESULTS: 97 cases were included (31 with novel device and 66 with existing device). Scope removal rate for the novel device was lower compared to the existing device (0.87 ± 1.02 vs 0.97 ± 1.20 removals/case, P = 0.69), but not statistically significant. Average number of debris events was also lower for the novel device, but not statistically significant (0.90 ± 0.94 vs 1.0 ± 1.18 debris events/case, P = 0.69). Average total time spent cleaning per case was similar between devices (16.9 ± 24.0 vs 15.9 ± 18.7 seconds, P = 0.82). CONCLUSION: This study demonstrates that a hydrophilic scope cleaning device has comparable performance to heated anti-fogging solution and may reduce scope removals and debris events. Direct comparisons between cleaning products are lacking. Surgeons are most likely to be successful with the cleaning strategy that best suits one's surgical practice.

10.
NMR Biomed ; : e5257, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39229964

RESUMEN

This study aimed to investigate the metabolic changes in the kidneys in a murine adenine-diet model of chronic kidney disease (CKD). Kidney fibrosis is the common pathological manifestation across CKD aetiologies. Sustained inflammation and fibrosis cause changes in preferred energy metabolic pathways in the cells of the kidney. Kidney cortical tissue from mice receiving a control or adenine-supplemented diet for 8 weeks (late inflammation and fibrosis) and 12 weeks (8 weeks of treatment followed by 4 weeks recovery) were analysed by 2D-correlated nuclear magnetic resonance spectroscopy and compared with histopathology and biomarkers of kidney damage. Tissue metabolite and lipid levels were assessed using the MestreNova software. Expression of genes related to inflammation, fibrosis, and metabolism were measured using quantitative polymerase chain reaction. Animals showed indicators of severely impaired kidney function at 8 and 12 weeks. Significantly increased fibrosis was present at 8 weeks but not in the recovery group suggesting some reversal of fibrosis and amelioration of inflammation. At 8 weeks, metabolites associated with glycolysis were increased, while lipid signatures were decreased. Genes involved in fatty acid oxidation were decreased at 8 weeks but not 12 weeks while genes associated with glycolysis were significantly increased at 8 weeks but not at 12 weeks. In this murine model of CKD, kidney fibrosis was associated with the accumulation of triglyceride and free lactate. There was an up-regulation of glycolytic enzymes and down-regulation of lipolytic enzymes. These metabolic changes reflect the energy demands associated with progressive kidney disease where there is a switch from fatty acid oxidation to that of glycolysis.

11.
Science ; 385(6711): 860-865, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39172840

RESUMEN

Effective fisheries management requires accurate estimates of stock biomass and trends; yet, assumptions in stock assessment models generate high levels of uncertainty and error. For 230 fisheries worldwide, we contrasted stock biomass estimates at the time of assessment with updated hindcast estimates modeled for the same year in later assessments to evaluate systematic over- or underestimation. For stocks that were overfished, low value, or located in regions with rising temperatures, historical biomass estimates were generally overstated compared with updated assessments. Moreover, rising trends reported for overfished stocks were often inaccurate. With consideration of bias identified retrospectively, 85% more stocks than currently recognized have likely collapsed below 10% of maximum historical biomass. The high uncertainty and bias in modeled stock estimates warrants much greater precaution by managers.


Asunto(s)
Biomasa , Explotaciones Pesqueras , Animales , Peces , Incertidumbre , Conservación de los Recursos Naturales , Modelos Teóricos
12.
Sci Rep ; 14(1): 19440, 2024 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-39169071

RESUMEN

In 2020, Denmark buried approximately four million culled, farmed mink in mass graves treated with slaked lime due to widespread SARS-CoV-2 infections. After six months, environmental concerns prompted the exhumation of these cadavers. Our analysis encompassed visual inspections, soil pH measurements, and gas emission assessments of the grave environment. Additionally, we evaluated carcasses for decay status, cadaverine content, and the presence of various pathogens, including SARS-CoV-2 and mink coronavirus. Our findings revealed minimal microbial activity and limited carcass decomposition. Although viral RNA from SARS-CoV-2 and mink coronavirus, along with DNA from Aleutian mink disease virus, were detected, the absence of infectious SARS-CoV-2 in cell culture assays suggests slow natural degradation processes. This study provides critical insights for future considerations in managing mass burial scenarios during outbreaks of livestock-associated zoonotic pathogens.


Asunto(s)
Entierro , COVID-19 , Visón , SARS-CoV-2 , Animales , Visón/virología , COVID-19/epidemiología , COVID-19/virología , SARS-CoV-2/aislamiento & purificación , Dinamarca , Pandemias , Cadáver , Humanos , ARN Viral/genética , Coronavirus/aislamiento & purificación , Coronavirus/genética
13.
Int J Cardiol ; 415: 132415, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39127146

RESUMEN

BACKGROUND: The role of ECG in ruling out myocardial complications on cardiac magnetic resonance (CMR) is unclear. We examined the clinical utility of ECG in screening for cardiac abnormalities on CMR among post-hospitalised COVID-19 patients. METHODS: Post-hospitalised patients (n = 212) and age, sex and comorbidity-matched controls (n = 38) underwent CMR and 12­lead ECG in a prospective multicenter follow-up study. Participants were screened for routinely reported ECG abnormalities, including arrhythmia, conduction and R wave abnormalities and ST-T changes (excluding repolarisation intervals). Quantitative repolarisation analyses included corrected QT (QTc), corrected QT dispersion (QTc disp), corrected JT (JTc) and corrected T peak-end (cTPe) intervals. RESULTS: At a median of 5.6 months, patients had a higher burden of ECG abnormalities (72.2% vs controls 42.1%, p = 0.001) and lower LVEF but a comparable cumulative burden of CMR abnormalities than controls. Patients with CMR abnormalities had more ECG abnormalities and longer repolarisation intervals than those with normal CMR and controls (82% vs 69% vs 42%, p < 0.001). Routinely reported ECG abnormalities had poor discriminative ability (area-under-the-receiver-operating curve: AUROC) for abnormal CMR, AUROC 0.56 (95% CI 0.47-0.65), p = 0.185; worse among female than male patients. Adding JTc and QTc disp improved the AUROC to 0.64 (95% CI 0.55-0.74), p = 0.002, the sensitivity of the ECG increased from 81.6% to 98.0%, negative predictive value from 84.7% to 96.3%, negative likelihood ratio from 0.60 to 0.13, and reduced sex-dependence variabilities of ECG diagnostic parameters. CONCLUSION: Post-hospitalised COVID-19 patients have more ECG abnormalities than controls. Normal ECGs, including normal repolarisation intervals, reliably exclude CMR abnormalities in male and female patients.


Asunto(s)
COVID-19 , Electrocardiografía , Imagen por Resonancia Cinemagnética , Humanos , COVID-19/diagnóstico por imagen , COVID-19/diagnóstico , Masculino , Femenino , Electrocardiografía/métodos , Estudios Prospectivos , Persona de Mediana Edad , Anciano , Imagen por Resonancia Cinemagnética/métodos , Estudios de Seguimiento , Adulto
14.
CNS Neurosci Ther ; 30(8): e14904, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39107947

RESUMEN

AIMS: Although static abnormalities of functional brain networks have been observed in patients with social anxiety disorder (SAD), the brain connectome dynamics at the macroscale network level remain obscure. We therefore used a multivariate data-driven method to search for dynamic functional network connectivity (dFNC) alterations in SAD. METHODS: We conducted spatial independent component analysis, and used a sliding-window approach with a k-means clustering algorithm, to characterize the recurring states of brain resting-state networks; then state transition metrics and FNC strength in the different states were compared between SAD patients and healthy controls (HC), and the relationship to SAD clinical characteristics was explored. RESULTS: Four distinct recurring states were identified. Compared with HC, SAD patients demonstrated higher fractional windows and mean dwelling time in the highest-frequency State 3, representing "widely weaker" FNC, but lower in States 2 and 4, representing "locally stronger" and "widely stronger" FNC, respectively. In State 1, representing "widely moderate" FNC, SAD patients showed decreased FNC mainly between the default mode network and the attention and perceptual networks. Some aberrant dFNC signatures correlated with illness duration. CONCLUSION: These aberrant patterns of brain functional synchronization dynamics among large-scale resting-state networks may provide new insights into the neuro-functional underpinnings of SAD.


Asunto(s)
Encéfalo , Conectoma , Imagen por Resonancia Magnética , Red Nerviosa , Fobia Social , Humanos , Masculino , Femenino , Adulto , Fobia Social/fisiopatología , Fobia Social/diagnóstico por imagen , Encéfalo/fisiopatología , Encéfalo/diagnóstico por imagen , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/fisiopatología , Adulto Joven
16.
Surg Endosc ; 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39179689

RESUMEN

INTRODUCTION: Robotic-assisted metabolic and bariatric surgery (MBS) is gaining popularity. Revisional MBS is associated with higher perioperative morbidity compared to primary MBS. The optimal surgical approach to minimize complications in these complex cases is unclear. The goal of this study was to assess robot utilization in revisional MBS and compare laparoscopic and robotic revisional MBS outcomes in the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) database. METHODS: A retrospective review of the MBSAQIP database was performed identifying revisional sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) cases from 2015 to 2022. Primary MBS, open/emergent cases, cases converted to another approach, and combined cases other than esophagogastroduodenoscopy were excluded. 30-Day outcomes for laparoscopic and robotic cases were compared using multivariate logistic regression adjusting for patient demographics, comorbidities, and operative variables. RESULTS: 41,404 Cases (14,474 SG; 26,930 RYGB) were identified. From 2015 to 2022, the percentage of revisional SG and RYGB cases performed robotically increased from 6.1% and 7.3% to 24.2% and 32.0% respectively. Laparoscopic SG had similar rates of overall morbidity, leak, bleeding, readmission, reoperation, and length of stay compared to robotic. Laparoscopic RYGB had significantly higher rates of overall morbidity (6.2% vs. 4.8%, p < 0.001, AOR 0.80 [0.70-0.93]), blood transfusion (1.5% vs. 1.0%, p < 0.05, AOR 0.74 [0.55-0.99]), superficial incisional SSI (1.2% vs. 0.4%, p < 0.001, AOR 0.30 [0.19-0.47]), and longer length of stay (1.87 vs. 1.76 days, p < 0.001) compared to robotic. Laparoscopic operative times were significantly shorter than robotic (SG: 86.4 ± 45.8 vs. 113.5 ± 51.7 min; RYGB: 130.7 ± 64.7 vs. 165.5 ± 66.8 min, p < 0.001). CONCLUSION: Robot utilization in revisional bariatric surgery is increasing. Robotic surgery has lower postoperative morbidity and shorter length of stay in revisional RYGB when compared to laparoscopic. Robotic platforms may have the capacity to improve the delivery of care for patients undergoing revisional bariatric surgery.

17.
Bioorg Chem ; 150: 107602, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38959647

RESUMEN

The binding affinities and interactions between eight drug candidates, both commercially available (candesartan; losartan; losartan carboxylic acid; nirmatrelvir; telmisartan) and newly synthesized benzimidazole-N-biphenyltetrazole (ACC519T), benzimidazole bis-N,N'-biphenyltetrazole (ACC519T(2) and 4-butyl-N,N-bis([2-(2H-tetrazol-5-yl)biphenyl-4-yl]) methyl (BV6), and the active site of angiotensin-converting enzyme-2 (ACE2) were evaluated for their potential as inhibitors against SARS-CoV-2 and regulators of ACE2 function through Density Functional Theory methodology and enzyme activity assays, respectively. Notably, telmisartan and ACC519T(2) exhibited pronounced binding affinities, forming strong interactions with ACE2's active center, favorably accepting proton from the guanidinium group of arginine273. The ordering of candidates by binding affinity and reactivity descriptors, emerged as telmisartan > ACC519T(2) > candesartan > ACC519T > losartan carboxylic acid > BV6 > losartan > nirmatrelvir. Proton transfers among the active center amino acids revealed their interconnectedness, highlighting a chain-like proton transfer involving tyrosine, phenylalanine, and histidine. Furthermore, these candidates revealed their potential antiviral abilities by influencing proton transfer within the ACE2 active site. Furthermore, through an in vitro pharmacological assays we determined that candesartan and the BV6 derivative, 4-butyl-N,N0-bis[20-2Htetrazol-5-yl)bipheyl-4-yl]methyl)imidazolium bromide (BV6(K+)2) also contain the capacity to increase ACE2 functional activity. This comprehensive analysis collectively underscores the promise of these compounds as potential therapeutic agents against SARS-CoV-2 by targeting crucial protein interactions.


Asunto(s)
Antagonistas de Receptores de Angiotensina , Enzima Convertidora de Angiotensina 2 , Teoría Funcional de la Densidad , SARS-CoV-2 , Enzima Convertidora de Angiotensina 2/metabolismo , Enzima Convertidora de Angiotensina 2/química , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/enzimología , Humanos , Antagonistas de Receptores de Angiotensina/farmacología , Antagonistas de Receptores de Angiotensina/química , Compuestos de Bifenilo/farmacología , Compuestos de Bifenilo/química , Antivirales/farmacología , Antivirales/química , Antivirales/síntesis química , COVID-19/virología , Relación Estructura-Actividad , Estructura Molecular , Bencimidazoles/farmacología , Bencimidazoles/química , Tetrazoles/farmacología , Tetrazoles/química , Tetrazoles/síntesis química , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/química , Inhibidores de la Enzima Convertidora de Angiotensina/metabolismo , Tratamiento Farmacológico de COVID-19
18.
Langmuir ; 40(28): 14527-14539, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38954522

RESUMEN

X-ray photoelectron spectroscopy (XPS) depth-profiling with an argon gas cluster ion source (GCIS) was used to characterize the spatial distribution of chlorophyll a (Chl) within a poly(cysteine methacrylate) (PCysMA) brush grown by surface-initiated atom-transfer radical polymerization (ATRP) from a planar surface. The organization of Chl is controlled by adjusting the brush grafting density and polymerization time. For dense brushes, the C, N, S elemental composition remains constant throughout the 36 nm brush layer until the underlying gold substrate is approached. However, for either reduced density brushes (mean thickness ∼20 nm) or mushrooms grown with reduced grafting densities (mean thickness 6-9 nm), elemental intensities decrease continuously throughout the brush layer, because photoelectrons are less strongly attenuated for such systems. For all brushes, the fraction of positively charged nitrogen atoms (N+/N0) decreases with increasing depth. Chl binding causes a marked reduction in N+/N0 within the brushes and produces a new feature at 398.1 eV in the N1s core-line spectrum assigned to tetrapyrrole ring nitrogen atoms coordinated to Zn2+. For all grafting densities, the N/S atomic ratio remains approximately constant as a function of brush depth, which indicates a uniform distribution of Chl throughout the brush layer. However, a larger fraction of repeat units bound to Chl is observed at lower grafting densities, reflecting a progressive reduction in steric congestion that enables more uniform distribution of the bulky Chl units throughout the brush layer. In summary, XPS depth-profiling using a GCIS is a powerful tool for characterization of these complex materials.

19.
Small ; : e2401982, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38992997

RESUMEN

Most organophosphates (OPs) are hydrophobic, and after exposure, can sequester into lipophilic regions within the body, such as adipose tissue, resulting in long term chronic effects. Consequently, there is an urgent need for therapeutic agents that can decontaminate OPs in these hydrophobic regions. Accordingly, an enzyme-polymer surfactant nanocomplex is designed and tested comprising chemically supercharged phosphotriesterase (Agrobacterium radiobacter; arPTE) electrostatically conjugated to amphiphilic polymer surfactant chains ([cat.arPTE][S-]). Experimentally-derived structural data are combined with molecular dynamics (MD) simulations to provide atomic level detail on conformational ensembles of the nanocomplex using dielectric constants relevant to aqueous and lipidic microenvironments. These show the formation of a compact admicelle pseudophase surfactant corona under aqueous conditions, which reconfigures to yield an extended conformation at a low dielectric constant, providing insight into the mechanism underpinning cell membrane binding. Significantly, it demonstrated that [cat.arPTE][S-] spontaneously binds to human mesenchymal stem cell membranes (hMSCs), resulting in on-cell OP hydrolysis. Moreover, the nanoconstruct can endocytose and partition into the intracellular fatty vacuoles of adipocytes and hydrolyze sequestered OP.

20.
Dalton Trans ; 53(30): 12460-12464, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39026506

RESUMEN

Reduction of hexaazatrinaphthylene (HAN) and its hexamethyl derivative with [Cp*2Sm(THF)2] or [Cp*2Yb(OEt2)] produces [(Cp*2Ln)3(R6HAN)] (Ln = Sm, Yb; R = H, Me), where the heterocyclic ligand forms as a trianion. The magnetism and electronic structure of these compounds reflect unusual multiconfigurational character within the reduced ligand but not the lanthanide ions.

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