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1.
Cancer Res ; 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39088700

RESUMEN

Oncogenic FGFR4 signaling represents a potential therapeutic target in various cancer types, including triple negative breast cancer (TNBC) and hepatocellular carcinoma (HCC). However, resistance to FGFR4 single-agent therapy remains a major challenge, emphasizing the need for effective combinatorial treatments. Our study sought to develop a comprehensive computational model of FGFR4 signaling and provide network-level insights into resistance mechanisms driven by signaling dynamics. An integrated approach, combining computational network modeling with experimental validation, uncovered potent AKT reactivation following FGFR4 targeting in TNBC cells. Analyzing the effects of co-targeting specific network nodes by systematically simulating the model predicted synergy of co-targeting FGFR4 and AKT or specific ErbB kinases, which was subsequently confirmed through experimental validation; however, co-targeting FGFR4 and PI3K was not synergistic. Protein expression data from hundreds of cancer cell lines was incorporated to adapt the model to diverse cellular contexts. This revealed that while AKT rebound was common, it was not a general phenomenon. For example, ERK reactivation occurred in certain cell types, including an FGFR4-driven HCC cell line, where there is a synergistic effect of co-targeting FGFR4 and MEK but not AKT. In summary, this study offers key insights into drug-induced network remodeling and the role of protein expression heterogeneity in targeted therapy responses. These findings underscore the utility of computational network modeling for designing cell type-selective combination therapies and enhancing precision cancer treatment.

2.
Lancet Infect Dis ; 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39098321

RESUMEN

BACKGROUND: Eumycetoma is an implantation mycosis characterised by a large subcutaneous mass in the extremities commonly caused by the fungus Madurella mycetomatis. Despite the long duration of treatment, commonly a minimum of 12 months, treatment failure is frequent and can lead to amputation. We aimed to compare the efficacy of two doses of fosravuconazole, a synthetic antifungal designed for use in onychomycosis and repurposed for mycetoma, with standard-of-care itraconazole, both in combination with surgery. METHODS: This phase 2, randomised, double-blind, active-controlled, superiority trial was conducted in a single centre in Sudan. Patients with eumycetoma caused by M mycetomatis, who were aged 15 years or older, with a set lesion diameter (>2 cm and ≤16 cm) requiring surgery were included. There was a limit of 20 female patients in the initial enrolment, owing to preclinical toxicity concerns. Exclusion criteria included previous surgical or medical treatment for eumycetoma; presence of loco-regional lymphatic extension; osteomyelitis, or other bone involvement; pregnancy or lactation; severe concomitant diseases; a BMI under 16 kg/m2; contraindication to use of the study drugs; pre-existing liver disease; lymphatic extension; osteomyelitis; transaminase levels more than two times the laboratory's upper limit of normal, or elevated levels of alkaline phosphatase or bilirubin; or any history of hypersensitivity to any azole antifungal drug. Patients were randomly allocated in a 1:1:1 ratio to 300 mg fosravuconazole weekly for 12 months (group 1); 200 mg fosravuconazole weekly for 12 months (group 2); or 400 mg itraconazole daily for 12 months (group 3) using a random number list with non-disclosed fixed blocks of size 12, with equal allocation to each of the three arms within a block. To ensure masking between groups, placebo pills were used to disguise the difference in dosing schedules. All groups took pills twice daily with meals. In all groups, surgery was performed at 6 months. The primary outcome was complete cure at end of treatment at the month 12 visit, as evidenced by absence of mycetoma mass, sinuses, and discharge; normal ultrasonography or MRI examination of the eumycetoma site; and, if a mass was present, negative fungal culture from the former mycetoma site. The primary outcome was assessed in the modified intention-to-treat (mITT) population (all patients who received one or more treatment dose with one or more primary efficacy assessment). Safety was assessed in all patients who received one or more doses of the study drug. This study is registered with ClinicalTrials.gov (NCT03086226) and is complete. FINDINGS: Between May 9, 2017, and June 10, 2021, 104 patients were randomly allocated (34 in group 1 and 2, respectively, and 36 in group 3). 86 (83%) of 104 patients were male and 18 (17%) patients were female. After an unplanned second interim analysis, the study was terminated early for futility. Complete cure at 12 months in the mITT population was 17 (50%) of 34 (95% CI 32-68) for group 1, 22 (65%) of 34 (47-80) for group 2, and 27 (75%) of 36 (58-88) in group 3. Neither dose of fosravuconazole was superior to itraconazole (p=0·35 for 200 mg fosravuconazole vs p=0·030 for 300 mg fosravuconazole). 83 patients had a total of 205 treatment-emergent adverse events, and two patients had serious adverse events that led to discontinuation, neither related to treatment. INTERPRETATION: Treatment with either dose of fosravuconazole was not superior to itraconazole, and the two doses had a numerically lower efficacy. However, fosravuconazole presented no new safety signals, and its lower pill burden and reduced risk of drug-drug interactions compared with the relatively expensive and inaccessible itraconazole suggests further research into effective treatments with a shorter duration and higher cure rate, without the need for surgery are warranted. FUNDING: Drugs for Neglected Diseases initiative.

3.
Artículo en Inglés | MEDLINE | ID: mdl-39099535

RESUMEN

Transcutaneous aortic valve replacement (TAVR) has evolved from a complex procedure meant only for patients at prohibitive risk for surgery to a commonly performed procedure across a wide variety of clinical scenarios including the treatment of failed aortic valve bioprosthesis. Annuloplasty rings in the aortic position such as HAART 300 (Biostable Science and Engineering) have been introduced in the management of native aortic regurgitation. Percutaneous management of failed bioprosthesis rings in the aortic position has not been widely described. We present a case of a 69-year-old man with recurrent aortic regurgitation successfully treated with TAVR using a SAPIEN 3 valve within a HAART 300 ring.

4.
J Clin Sleep Med ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39132686

RESUMEN

STUDY OBJECTIVES: To translate, culturally adapt, and validate the Neurological Sleep Index - Multiple Sclerosis (NSI-MS) for use in Austrian German-speaking populations with multiple sclerosis (pwMS). METHODS: Following established guidelines, the NSI-MS diurnal sleepiness (DS), non-restorative nocturnal sleep (NRNS), and fragmented nocturnal sleep (FNS) scales underwent forward-backward translation, with content and face validity, and cultural adaptation to Austria established. Construct validity was evaluated using Rasch analysis. Known-groups validity was examined, and comparisons were made with scales measuring MS fatigue, daytime sleepiness, sleep quality, anxiety, and depression. Reliability was assessed through Cronbach's alpha, Person Separation Index, Lin's concordance correlation coefficient, measurement error, and floor and ceiling effects. Data were merged with a historic English dataset for comparison between English/German language versions. RESULTS: The translation and cultural adaptation of the NSI-MS-G were successful. Pretesting involved 30 pwMS, while the validation included 400 pwMS with mild-to-severe disability. The DS, NRNS, and FNS scales exhibited good fit parameters, were unidimensional, and invariant. NSI-MS-G scales demonstrated excellent convergent and known-groups validity, internal consistency, person separation reliability, test-retest reliability, adequate measurement error, and low floor and ceiling effects. Pooling English and German datasets revealed that person estimates for the NRNS and FNS scales are equivalent across versions, unlike the DS scale. CONCLUSIONS: The NSI-MS-G demonstrates validity, reliability, and responsiveness in assessing DS, NRNS, and FNS in pwMS, generating interval-level data, and shows equivalence between its English and German versions. CLINICAL TRIAL REGISTRATION: Register: German Clinical Trials Register (DRKS); URL: https://drks.de/search/en/trial/DRKS00025573; Identifier: DRKS00025573.

5.
Nature ; 632(8025): 550-556, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39143342

RESUMEN

The unimolecular heterolysis of covalent σ-bonds is integral to many chemical transformations, including SN1-, E1- and 1,2-migration reactions. To a first approximation, the unequal redistribution of electron density during bond heterolysis is governed by the difference in polarity of the two departing bonding partners1-3. This means that if a σ-bond consists of two identical groups (that is, symmetric σ-bonds), its unimolecular fission from the S0, S1, or T1 states only occurs homolytically after thermal or photochemical activation1-7. To force symmetric σ-bonds into heterolytic manifolds, co-activation by bimolecular noncovalent interactions is necessary4. These tactics are only applicable to σ-bond constituents susceptible to such polarizing effects, and often suffer from inefficient chemoselectivity in polyfunctional molecules. Here we report the net heterolysis of symmetric and homopolar σ-bonds (that is, those with similar electronegativity and equal leaving group ability3) by means of stimulated doublet-doublet electron transfer (SDET). As exemplified by Se-Se and C-Se σ-bonds, symmetric and homopolar bonds initially undergo thermal homolysis, followed by photochemically SDET, eventually leading to net heterolysis. Two key factors make this process feasible and synthetically valuable: (1) photoexcitation probably occurs in only one of the incipient radical pair members, thus leading to coincidental symmetry breaking8 and consequently net heterolysis even of symmetric σ-bonds. (2) If non-identical radicals are formed, each radical may be excited at different wavelengths, thus rendering the net heterolysis highly chemospecific and orthogonal to conventional heterolyses. This feature is demonstrated in a series of atypical SN1 reactions, in which selenides show SDET-induced nucleofugalities3 rivalling those of more electronegative halides or diazoniums.

6.
Nat Commun ; 15(1): 7219, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39174507

RESUMEN

Anelloviruses are nonpathogenic viruses that comprise a major portion of the human virome. Despite being ubiquitous in the human population, anelloviruses (ANVs) remain poorly understood. Basic features of the virus, such as the identity of its capsid protein and the structure of the viral particle, have been unclear until now. Here, we use cryogenic electron microscopy to describe the first structure of an ANV-like particle. The particle, formed by 60 jelly roll domain-containing ANV capsid proteins, forms an icosahedral particle core from which spike domains extend to form a salient part of the particle surface. The spike domains come together around the 5-fold symmetry axis to form crown-like features. The base of the spike domain, the P1 subdomain, shares some sequence conservation between ANV strains while a hypervariable region, forming the P2 subdomain, is at the spike domain apex. We propose that this structure renders the particle less susceptible to antibody neutralization by hiding vulnerable conserved domains while exposing highly diverse epitopes as immunological decoys, thereby contributing to the immune evasion properties of anelloviruses. These results shed light on the structure of anelloviruses and provide a framework to understand their interactions with the immune system.


Asunto(s)
Proteínas de la Cápside , Microscopía por Crioelectrón , Evasión Inmune , Virión , Proteínas de la Cápside/química , Proteínas de la Cápside/inmunología , Proteínas de la Cápside/ultraestructura , Virión/ultraestructura , Virión/inmunología , Humanos , Anelloviridae/genética , Anelloviridae/inmunología , Modelos Moleculares , Dominios Proteicos , Epítopos/inmunología , Epítopos/química , Secuencia de Aminoácidos
7.
Sci Total Environ ; 951: 175528, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39147048

RESUMEN

Eco-engineering of coastal infrastructure aims to address the insufficient intertidal habitat provided by coastal development and flood defence. There are numerous ways to enhance coastal infrastructure with habitat features, but a common method involves retrofitting artificial rockpools. Often these are 'bolt-on' units that are fixed to existing coastal infrastructure but there is a paucity of literature on how to optimise their arrangement for biodiversity. In this study, 24 artificial rockpools were installed at three levels between High Water Neaps and Mean Tide Level on a vertical concrete seawall on the south coast of the UK. The species abundance of the rockpools and adjacent seawall were surveyed at low tide for 2 years following rockpool installation and compared. Over the course of the study, sediment had begun to accumulate in some of the rockpools. At the 2-year mark, the sediment was removed and assessed for macrofauna. Algal biomass of the seawall and rockpools was estimated using previously obtained dry weight values for the dominant algae taxa. After 2 years, it was determined that artificial rockpools successfully increase species richness of seawalls, particularly at higher tidal levels where water-retaining refugia are crucial for many species. The rockpools hosted 37 sessile taxa and 9 sessile taxa were recorded on the seawall. Rockpools increased the vertical elevation for brown canopy-forming seaweeds by providing better attachment surfaces. Although the retained sediment only hosted 3 infaunal species, it was observed to provide shelter for shore crabs during surveys. As sea levels and ocean and air temperatures continue to rise, vertical eco-engineering arrangements will play a crucial role in allowing species to migrate up the tidal zone, negating habitat loss and localised extinction.

8.
Front Cardiovasc Med ; 11: 1410305, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39165257

RESUMEN

The past five years have yielded impressive advancements in fully absorbable metal stent technology. The desired ultimate ability for such devices to treat a vascular stenosis without long-term device-related complications or impeding future treatment continues to evoke excitement in clinicians and engineers alike. Nowhere is the need for fully absorbable metal stents greater than in patients experiencing vascular anomalies associated with congenital heart disease (CHD). Perhaps not surprisingly, commercially available absorbable metal stents have been implanted in pediatric cardiology patients with conditions ranging from pulmonary artery and vein stenosis to coarctation of the aorta and conduit/shunt reconstructions. Despite frequent short term procedural success, device performance has missed the mark with the commercially available devices not achieving degradation benchmarks for given applications. In this review we first provide a general overview detailing the theory of absorbable metal stents, and then review recent clinical use in CHD patients since the release of current-generation absorbable metal stents around 2019. We also discuss the challenges and our center's experience associated with the use of absorbable metal stents in this pediatric population. Lastly, we present potential directions for future engineering endeavors to mitigate existing challenges.

9.
Structure ; 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-39013462

RESUMEN

The scaffold proteins JIP1 and JIP2 intervene in the c-Jun N-terminal kinase (JNK) pathway to mediate signaling specificity by coordinating the simultaneous assembly of multiple kinases. Using NMR, we demonstrate that JIP1 and JIP2 heterodimerize via their SH3 domains with the affinity of heterodimerization being comparable to homodimerization. We present the high-resolution crystal structure of the JIP2-SH3 homodimer and the JIP1-JIP2-SH3 heterodimeric complex. The JIP2-SH3 structure reveals how charge differences in residues at its dimer interface lead to formation of compensatory hydrogen bonds and salt bridges, distinguishing it from JIP1-SH3. In the JIP1-JIP2-SH3 complex, structural features of each homodimer are employed to stabilize the heterodimer. Building on these insights, we identify key residues crucial for stabilizing the dimer of both JIP1 and JIP2. Through targeted mutations in cellulo, we demonstrate a functional role for the dimerization of the JIP1 and JIP2 scaffold proteins in activation of the JNK signaling pathway.

10.
Trials ; 25(1): 502, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39044295

RESUMEN

BACKGROUND: Cardiac arrest is a common and devastating emergency of both the heart and brain. More than 380,000 patients suffer out-of-hospital cardiac arrest annually in the USA. Induced cooling of comatose patients markedly improved neurological and functional outcomes in pivotal randomized clinical trials, but the optimal duration of therapeutic hypothermia has not yet been established. METHODS: This study is a multi-center randomized, response-adaptive, duration (dose) finding, comparative effectiveness clinical trial with blinded outcome assessment. We investigate two populations of adult comatose survivors of cardiac arrest to ascertain the shortest duration of cooling that provides the maximum treatment effect. The design is based on a statistical model of response as defined by the primary endpoint, a weighted 90-day mRS (modified Rankin Scale, a measure of neurologic disability), across the treatment arms. Subjects will initially be equally randomized between 12, 24, and 48 h of therapeutic cooling. After the first 200 subjects have been randomized, additional treatment arms between 12 and 48 h will be opened and patients will be allocated, within each initial cardiac rhythm type (shockable or non-shockable), by response adaptive randomization. As the trial continues, shorter and longer duration arms may be opened. A maximum sample size of 1800 subjects is proposed. Secondary objectives are to characterize: the overall safety and adverse events associated with duration of cooling, the effect on neuropsychological outcomes, and the effect on patient-reported quality of life measures. DISCUSSION: In vitro and in vivo studies have shown the neuroprotective effects of therapeutic hypothermia for cardiac arrest. We hypothesize that longer durations of cooling may improve either the proportion of patients that attain a good neurological recovery or may result in better recovery among the proportion already categorized as having a good outcome. If the treatment effect of cooling is increasing across duration, for at least some set of durations, then this provides evidence of the efficacy of cooling itself versus normothermia, even in the absence of a normothermia control arm, confirming previous RCTs for OHCA survivors of shockable rhythms and provides the first prospective controlled evidence of efficacy in those without initial shockable rhythms. TRIAL REGISTRATION: ClinicalTrials.gov NCT04217551. Registered on 30 December 2019.


Asunto(s)
Coma , Hipotermia Inducida , Estudios Multicéntricos como Asunto , Paro Cardíaco Extrahospitalario , Ensayos Clínicos Controlados Aleatorios como Asunto , Humanos , Hipotermia Inducida/métodos , Hipotermia Inducida/efectos adversos , Paro Cardíaco Extrahospitalario/terapia , Paro Cardíaco Extrahospitalario/fisiopatología , Coma/terapia , Coma/etiología , Coma/fisiopatología , Factores de Tiempo , Resultado del Tratamiento , Recuperación de la Función , Neuroprotección , Estados Unidos , Investigación sobre la Eficacia Comparativa
11.
Nat Commun ; 15(1): 6264, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39048565

RESUMEN

Opioid withdrawal is a liability of chronic opioid use and misuse, impacting people who use prescription or illicit opioids. Hyperactive autonomic output underlies many of the aversive withdrawal symptoms that make it difficult to discontinue chronic opioid use. The locus coeruleus (LC) is an important autonomic centre within the brain with a poorly defined role in opioid withdrawal. We show here that pannexin-1 (Panx1) channels expressed on microglia critically modulate LC activity during opioid withdrawal. Within the LC, we found that spinally projecting tyrosine hydroxylase (TH)-positive neurons (LCspinal) are hyperexcitable during morphine withdrawal, elevating cerebrospinal fluid (CSF) levels of norepinephrine. Pharmacological and chemogenetic silencing of LCspinal neurons or genetic ablation of Panx1 in microglia blunted CSF NE release, reduced LC neuron hyperexcitability, and concomitantly decreased opioid withdrawal behaviours in mice. Using probenecid as an initial lead compound, we designed a compound (EG-2184) with greater potency in blocking Panx1. Treatment with EG-2184 significantly reduced both the physical signs and conditioned place aversion caused by opioid withdrawal in mice, as well as suppressed cue-induced reinstatement of opioid seeking in rats. Together, these findings demonstrate that microglial Panx1 channels modulate LC noradrenergic circuitry during opioid withdrawal and reinstatement. Blocking Panx1 to dampen LC hyperexcitability may therefore provide a therapeutic strategy for alleviating the physical and aversive components of opioid withdrawal.


Asunto(s)
Conexinas , Locus Coeruleus , Proteínas del Tejido Nervioso , Probenecid , Médula Espinal , Síndrome de Abstinencia a Sustancias , Animales , Locus Coeruleus/metabolismo , Locus Coeruleus/efectos de los fármacos , Conexinas/metabolismo , Conexinas/genética , Conexinas/antagonistas & inhibidores , Proteínas del Tejido Nervioso/metabolismo , Proteínas del Tejido Nervioso/genética , Síndrome de Abstinencia a Sustancias/metabolismo , Síndrome de Abstinencia a Sustancias/tratamiento farmacológico , Ratones , Masculino , Ratas , Médula Espinal/metabolismo , Médula Espinal/efectos de los fármacos , Probenecid/farmacología , Morfina/farmacología , Microglía/efectos de los fármacos , Microglía/metabolismo , Analgésicos Opioides/farmacología , Norepinefrina/metabolismo , Neuronas/metabolismo , Neuronas/efectos de los fármacos , Ratones Endogámicos C57BL , Ratas Sprague-Dawley , Tirosina 3-Monooxigenasa/metabolismo , Ratones Noqueados
13.
Blood ; 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38996211

RESUMEN

Rondaptivan pegol (previously BT200) is a PEGylated RNA aptamer that binds to the A1 domain of VWF. Recent clinical trials demonstrated that BT200 significantly increased plasma VWF-FVIII levels by attenuating VWF clearance. The biological mechanism(s) through which BT200 attenuates in vivo clearance of VWF have not been defined. We hypothesized that BT200 interaction with the VWF-A1 domain may increase plasma VWF levels by attenuating macrophage-mediated clearance. We observed that full length- and VWF-A1A2A3 binding to macrophages, and VWF-A1 domain binding to LRP1 cluster II and cluster IV, were concentration-dependently inhibited by BT200. Additionally, full length VWF binding to LRP1 expressed on HEK293T (HEK-LRP1) cells was also inhibited by BT200. Importantly, BT200 interacts with the VWF-A1 domain in proximity to a conserved cluster of four lysine residues (K1405, K1406, K1407 and K1408). Alanine mutagenesis of this K1405-K1408 cluster (VWF-4A) significantly (p<0.001) attenuated binding of VWF to both LRP1 clusters II and IV. Furthermore, in vivo clearance of VWF-4A was significantly (p<0.001) reduced compared to wild type VWF. BT200 did not significantly inhibit binding of VWF-4A to LRP1 cluster IV or HEK-LRP1 cells. Finally, BT200 interaction with the VWF-A1 domain also inhibited binding to macrophage galactose lectin (MGL) and the SR-AI scavenger receptor. Collectively, our findings demonstrate that BT200 prolongs VWF half-life by attenuating macrophage-mediated clearance and specifically the interaction of K1405-1408 in the VWF-A1 domain with macrophage LRP1. These data support the concept that targeted inhibition of VWF clearance pathways represent a novel therapeutic approach for VWD and hemophilia A.

14.
Neurooncol Adv ; 6(1): vdae108, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39027132

RESUMEN

Background: Diffuse midline gliomas (DMG) are aggressive pediatric brain tumors that are diagnosed and monitored through MRI. We developed an automatic pipeline to segment subregions of DMG and select radiomic features that predict patient overall survival (OS). Methods: We acquired diagnostic and post-radiation therapy (RT) multisequence MRI (T1, T1ce, T2, and T2 FLAIR) and manual segmentations from 2 centers: 53 from 1 center formed the internal cohort and 16 from the other center formed the external cohort. We pretrained a deep learning model on a public adult brain tumor data set (BraTS 2021), and finetuned it to automatically segment tumor core (TC) and whole tumor (WT) volumes. PyRadiomics and sequential feature selection were used for feature extraction and selection based on the segmented volumes. Two machine learning models were trained on our internal cohort to predict patient 12-month survival from diagnosis. One model used only data obtained at diagnosis prior to any therapy (baseline study) and the other used data at both diagnosis and post-RT (post-RT study). Results: Overall survival prediction accuracy was 77% and 81% for the baseline study, and 85% and 78% for the post-RT study, for internal and external cohorts, respectively. Homogeneous WT intensity in baseline T2 FLAIR and larger post-RT TC/WT volume ratio indicate shorter OS. Conclusions: Machine learning analysis of MRI radiomics has potential to accurately and noninvasively predict which pediatric patients with DMG will survive less than 12 months from the time of diagnosis to provide patient stratification and guide therapy.

15.
Res Sq ; 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38947064

RESUMEN

Background: Cardiac arrest is a common and devastating emergency of both the heart and brain. More than 380,000 patients suffer out-of-hospital cardiac arrest annually in the United States. Induced cooling of comatose patients markedly improved neurological and functional outcomes in pivotal randomized clinical trials, but the optimal duration of therapeutic hypothermia has not yet been established. Methods: This study is a multi-center randomized, response-adaptive, duration (dose) finding, comparative effectiveness clinical trial with blinded outcome assessment. We investigate two populations of adult comatose survivors of cardiac arrest to ascertain the shortest duration of cooling that provides the maximum treatment effect. The design is based on a statistical model of response as defined by the primary endpoint, a weighted 90-day mRS (modified Rankin Scale, a measure of neurologic disability), across the treatment arms. Subjects will initially be equally randomized between 12, 24, and 48 hours of therapeutic cooling. After the first 200 subjects have been randomized, additional treatment arms between 12 and 48 hours will be opened and patients will be allocated, within each initial cardiac rhythm type (shockable or non-shockable), by response adaptive randomization. As the trial continues, shorter and longer duration arms may be opened. A maximum sample size of 1800 subjects is proposed. Secondary objectives are to characterize: the overall safety and adverse events associated with duration of cooling, the effect on neuropsychological outcomes, and the effect on patient reported quality of life measures. Discussion: In-vitro and in-vivo studies have shown the neuroprotective effects of therapeutic hypothermia for cardiac arrest. We hypothesize that longer durations of cooling may improve either the proportion of patients that attain a good neurological recovery or may result in better recovery among the proportion already categorized as having a good outcome. If the treatment effect of cooling is increasing across duration, for at least some set of durations, then this provides evidence of the efficacy of cooling itself versus normothermia, even in the absence of a normothermia control arm, confirming previous RCTs for OHCA survivors of shockable rhythms and provides the first prospective controlled evidence of efficacy in those without initial shockable rhythms. Trial registration: ClinicalTrials.gov (NCT04217551, 2019-12-30).

16.
Bioact Mater ; 40: 74-87, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38962657

RESUMEN

Flow diverter devices are small stents used to divert blood flow away from aneurysms in the brain, stagnating flow and inducing intra-aneurysmal thrombosis which in time will prevent aneurysm rupture. Current devices are formed from thin (∼25 µm) wires which will remain in place long after the aneurysm has been mitigated. As their continued presence could lead to secondary complications, an absorbable flow diverter which dissolves into the body after aneurysm occlusion is desirable. The absorbable metals investigated to date struggle to achieve the necessary combination of strength, elasticity, corrosion rate, fragmentation resistance, radiopacity, and biocompatibility. This work proposes and investigates a new composite wire concept combining absorbable iron alloy (FeMnN) shells with one or more pure molybdenum (Mo) cores. Various wire configurations are produced and drawn to 25-250 µm wires. Tensile testing revealed high and tunable mechanical properties on par with existing flow diverter materials. In vitro degradation testing of 100 µm wire in DMEM to 7 days indicated progressive corrosion and cracking of the FeMnN shell but not of the Mo, confirming the cathodic protection of the Mo by the FeMnN and thus mitigation of premature fragmentation risk. In vivo implantation and subsequent µCT of the same wires in mouse aortas to 6 months showed meaningful corrosion had begun in the FeMnN shell but not yet in the Mo filament cores. In total, these results indicate that these composites may offer an ideal combination of properties for absorbable flow diverters.

17.
bioRxiv ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-39005385

RESUMEN

Multicellular spheroids embedded in 3D hydrogels are prominent in vitro models for 3D cell invasion. Yet, quantification methods for spheroid cell invasion that are high-throughput, objective and accessible are still lacking. Variations in spheroid sizes and the shapes of the cells within render it difficult to objectively assess invasion extent. The goal of this work is to develop a high-throughput quantification method of cell invasion into 3D matrices that minimizes sensitivity to initial spheroid size and cell spreading and provides precise integrative directionally-dependent metrics of invasion. By analyzing images of fluorescent cell nuclei, invasion metrics are automatically calculated at the pixel level. The initial spheroid boundary is segmented and automated calculations of the nuclear pixel distances from the initial boundary are used to compute common invasion metrics (i.e., the change in invasion area, mean distance) for the same spheroid at a later timepoint. We also introduce the area moment of inertia as an integrative metric of cell invasion that considers the invasion area as well as the pixel distances from the initial spheroid boundary. Further, we show that principal component analysis can be used to quantify the directional influence of a stimuli to invasion (e.g., due to a chemotactic gradient or contact guidance). To demonstrate the power of the analysis for cell types with different invasive potentials and the utility of this method for a variety of biological applications, the method is used to analyze the invasiveness of five different cell types. In all, implementation of this high-throughput quantification method results in consistent and objective analysis of 3D multicellular spheroid invasion. We provide the analysis code in both MATLAB and Python languages as well as a GUI for ease of use for researchers with a range of computer programming skills and for applications in a variety of biological research areas such as wound healing and cancer metastasis.

18.
JCO Precis Oncol ; 8: e2300590, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38976815

RESUMEN

PURPOSE: Midline low-grade gliomas (mLGGs) of early childhood have a poorer prognosis compared with tumors of other localizations and in older patients. LGGs are associated with aberrant activation of RAS-RAF-MEK pathway, and pharmacological inhibition of the pathway has therapeutic promise. The aim of this study was clinical and molecular characterization of infantile mLGGs, with emphasis on the efficacy of targeted kinase inhibition. PATIENTS AND METHODS: This study enrolled 40 patients with mLGG age <3 years. The majority of the patients (30/40) received first-line chemotherapy (CT) as per International Society of Paediatric Oncology LGG 2004 guidelines. In all patients, molecular genetic investigation of tumor tissue by polymerase chain reaction and RNA sequencing was performed. The median follow-up was 3.5 years. RESULTS: First-line CT failed in 24 of 30 recipients. The identified molecular profiles included KIAA1549::BRAF fusions in 26 patients, BRAF V600E in six patients, FGFR1::TACC1 fusions in two patients, and rare fusion transcripts in four patients. At disease progression, targeted therapy (TT) was initiated in 27 patients (22 patients received trametinib) on the basis of molecular findings. TT was administered for a median of 16 months, with partial response achieved in 12 of 26 (46%) patients in which response was evaluated. Severe adverse events were detected only on trametinib monotherapy: acute damage of GI or urinary mucosa complicated by hemorrhage and development of transfusion-dependent anemia in four patients and grade 3 skin toxicity in three patients. CONCLUSION: mLGGs of early childhood are often aggressive tumors, resistant to CT, and frequently require alternative treatment. The majority of patients harbor druggable molecular targets and respond to molecular TT.


Asunto(s)
Neoplasias Encefálicas , Glioma , Terapia Molecular Dirigida , Humanos , Glioma/genética , Glioma/tratamiento farmacológico , Masculino , Femenino , Lactante , Preescolar , Terapia Molecular Dirigida/métodos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/tratamiento farmacológico
19.
Muscle Nerve ; 70(3): 387-394, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38953614

RESUMEN

INTRODUCTION/AIMS: Fatigue is a common and debilitating symptom encountered in the neuromuscular clinic. The 7-item Fatigue Severity Scale (FSS-7) is a Rasch-modified assessment validated in inflammatory neuropathies but not across a typical neuromuscular patient population. The aim of this study was to validate this measure in neuromuscular disorders and to compare between patient sex, age and diagnoses. METHODS: The modified FSS-7 was mailed to patients recruited from a specialist neuromuscular clinic at the Walton Centre. Responses were subjected to Rasch analysis and descriptive statistics were performed on the Rasch converted data. RESULTS: The mFSS-7 met the Rasch model expectations with an overall Chi-square probability of 0.4918, a strict unidimensional scale free from differential item functioning (DIF) that satisfied the model with substantial test-retest reliability using Lin's concordance correlation coefficient 0.71 (95% CI 0.63-0.77). A 15.7% ceiling effect was observed in this patient cohort. Post hoc analysis did not show any significant difference in fatigue between sex, age or neuromuscular diagnoses. DISCUSSION: The self-completed Rasch mFSS-7 showed acceptable test-retest reliability across patients with varied disorders under follow-up in a specialist neuromuscular clinic. The ceiling effect constrains its use for those with the most severe fatigue. Future considerations could include assessment of the benefits of clinical interventions, particularly multidisciplinary team input or dedicated fatigue clinics.


Asunto(s)
Fatiga , Enfermedades Neuromusculares , Índice de Severidad de la Enfermedad , Humanos , Masculino , Femenino , Persona de Mediana Edad , Enfermedades Neuromusculares/diagnóstico , Enfermedades Neuromusculares/fisiopatología , Fatiga/diagnóstico , Fatiga/etiología , Fatiga/fisiopatología , Adulto , Reproducibilidad de los Resultados , Anciano , Factores Sexuales , Factores de Edad , Psicometría , Adulto Joven , Encuestas y Cuestionarios/normas
20.
ACS Appl Bio Mater ; 7(8): 5382-5396, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-38992948

RESUMEN

The programmed fabrication of oral dosage forms is associated with several challenges such as controlled loading and disintegration. To optimize the drug payload, excipient breakdown, and site-specific sustained release of hydrophobic drug (sulfamethoxazole, SM), we propose the development of acrylate polymer tablets enclosed with drug-loaded polycaprolactone (PCL) films. The active pharmaceutical ingredient (API) is physisorbed into the porous iron (Fe)-based metal-organic framework (MOF) and later converted to tangible PCL films, which, upon folding, are incorporated into the acrylate polymer matrices (P1/P2/P3). X-ray powder diffraction (XRPD) analysis and scanning electron microscopy (SEM) micrographs confirmed the stability and homogeneous distribution of MOF within the 50 µm thick film. Adsorption-desorption measurements at ambient temperatures confirmed the decrease in the BET surface area of PCL films by 40%, which was ∼3.01 m/g, and pore volume from 30 to 9 nm. The decrease in adsorption and surface parameters could confirm the gradual accessibility of SM molecules once exposed to a degrading environment. Fourier transform infrared (FTIR) analyses of in vitro dissolution confirmed the presence of the drug in the MOF-PCL film-enclosed tablets and concluded the cumulative SM release at pH ∼ 8.2 which followed the order SM@Fe-MOF < P1/P2/P3 < PCL-SM@Fe-MOF < P1/PCL-SM@Fe-MOF < P3/PCL-SM@Fe-MOF. The results of the study indicate that the P3/PCL-SM@Fe-MOF assembly has potential use as a biomedical drug delivery alternative carrier for effective drug loading and stimuli-responsive flexible release to attain high bioavailability.


Asunto(s)
Materiales Biocompatibles , Preparaciones de Acción Retardada , Ensayo de Materiales , Estructuras Metalorgánicas , Tamaño de la Partícula , Poliésteres , Estructuras Metalorgánicas/química , Poliésteres/química , Materiales Biocompatibles/química , Materiales Biocompatibles/síntesis química , Preparaciones de Acción Retardada/química , Liberación de Fármacos , Propiedades de Superficie , Portadores de Fármacos/química , Polímeros/química
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