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1.
Nat Methods ; 21(9): 1608-1611, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38969722

RESUMEN

Detecting microsecond structural perturbations in biomolecules has wide relevance in biology, chemistry and medicine. Here we show how MHz repetition rates at X-ray free-electron lasers can be used to produce microsecond time-series of protein scattering with exceptionally low noise levels of 0.001%. We demonstrate the approach by examining Jɑ helix unfolding of a light-oxygen-voltage photosensory domain. This time-resolved acquisition strategy is easy to implement and widely applicable for direct observation of structural dynamics of many biochemical processes.


Asunto(s)
Difracción de Rayos X , Difracción de Rayos X/métodos , Rayos Láser , Rayos X , Factores de Tiempo
2.
N Engl J Med ; 388(9): 804-812, 2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36856616

RESUMEN

BACKGROUND: Immunosuppressed organ-transplant recipients have an increased incidence of, and mortality from, skin cancer. Nicotinamide (vitamin B3) enhances the repair of ultraviolet (UV) radiation-induced DNA damage, reduces the cutaneous immunosuppressive effects of UV radiation, and reduces the incidence of keratinocyte cancers (including squamous-cell and basal-cell carcinomas) and actinic keratoses among high-risk immunocompetent patients. Whether oral nicotinamide is useful for skin-cancer chemoprevention in organ-transplant recipients is unclear. METHODS: In this phase 3 trial, we randomly assigned, in a 1:1 ratio, organ-transplant recipients who had had at least two keratinocyte cancers in the past 5 years to receive 500 mg of nicotinamide or placebo twice daily for 12 months. Participants were examined for skin lesions by dermatologists at 3-month intervals for 12 months. The primary end point was the number of new keratinocyte cancers during the 12-month intervention period. Secondary end points included the numbers of squamous-cell and basal-cell carcinomas during the 12-month intervention period, the number of actinic keratoses until 6 months after randomization, safety, and quality of life. RESULTS: A total of 158 participants were enrolled, with 79 assigned to the nicotinamide group and 79 to the placebo group. The trial was stopped early owing to poor recruitment. At 12 months, there were 207 new keratinocyte cancers in the nicotinamide group and 210 in the placebo group (rate ratio, 1.0; 95% confidence interval, 0.8 to 1.3; P = 0.96). No significant between-group differences in squamous-cell and basal-cell carcinoma counts, actinic keratosis counts, or quality-of-life scores were observed. Adverse events and changes in blood or urine laboratory variables were similar in the two groups. CONCLUSIONS: In this 12-month, placebo-controlled trial, oral nicotinamide therapy did not lead to lower numbers of keratinocyte cancers or actinic keratoses in immunosuppressed solid-organ transplant recipients. (Funded by the National Health and Medical Research Council; ONTRANS Australian New Zealand Clinical Trials Registry number, ACTRN12617000599370.).


Asunto(s)
Antineoplásicos , Niacinamida , Neoplasias Cutáneas , Receptores de Trasplantes , Humanos , Australia , Carcinoma Basocelular/etiología , Carcinoma Basocelular/prevención & control , Carcinoma de Células Escamosas/etiología , Carcinoma de Células Escamosas/prevención & control , Quimioprevención , Queratosis Actínica/etiología , Queratosis Actínica/prevención & control , Niacinamida/administración & dosificación , Niacinamida/uso terapéutico , Calidad de Vida , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/prevención & control , Huésped Inmunocomprometido , Trasplante de Órganos/efectos adversos , Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Rayos Ultravioleta/efectos adversos
3.
PLoS Pathog ; 20(2): e1011502, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38377133

RESUMEN

Host resistance to a common protozoan parasite Toxoplasma gondii relies on a coordinated immune response involving multiple cell types, including macrophages. Embryonically seeded tissue-resident macrophages (TRMs) play a critical role in maintaining tissue homeostasis, but their role in parasite clearance is poorly understood. In this study, we uncovered a crucial aspect of host defense against T. gondii mediated by TRMs. Through the use of neutralizing antibodies and conditional IFN-γ receptor-deficient mice, we demonstrated that IFN-γ directly mediated the elimination of TRMs. Mechanistically, IFN-γ stimulation in vivo rendered macrophages unresponsive to macrophage colony-stimulating factor (M-CSF) and inactivated mTOR signaling by causing the shedding of CD115 (CSFR1), the receptor for M-CSF. Further experiments revealed the essential role of macrophage IFN-γ responsiveness in host resistance to T. gondii. The elimination of peritoneal TRMs emerged as an additional host defense mechanism aimed at limiting the parasite's reservoir. The identified mechanism, involving IFN-γ-induced suppression of CD115-dependent mTOR signaling in macrophages, provides insights into the adaptation of macrophage subsets during infection and highlights a crucial aspect of host defense against intracellular pathogens.


Asunto(s)
Parásitos , Animales , Ratones , Factor Estimulante de Colonias de Macrófagos , Macrófagos , Proteínas Tirosina Quinasas Receptoras , Serina-Treonina Quinasas TOR
4.
Nano Lett ; 24(6): 1967-1973, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38289648

RESUMEN

Interfaces play a critical thermodynamic role in the existence of multilayer systems. Due to their utility in bridging energetic and compositional differences between distinct species, the formation of interfaces inherently creates internal strain in the bulk due to the reorganization needed to accommodate such a change. We report the effect of scaling interfacial stress by deposition of different adlayers on a host thin metal film. Intrinsic property differences between host and deposited metal atoms result in varying degree of composition and energy gradient within the interface. Interfacial stress can increase defects in the host leading to (i) energy dissipation and reorganization to minimize surface energy, and (ii) increased material strength. We infer that dissipation of interfacial stress induces defect migration, hence bulk and surface atomic reconstruction as captured by the surface roughness and grain size reduction coupled with a concomitant increase in material strength.

5.
Lancet Oncol ; 25(1): 99-107, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38043558

RESUMEN

BACKGROUND: The TheraP study reported improved prostate-specific antigen responses with lutetium-177 [177Lu]Lu-PSMA-617 versus cabazitaxel in men with metastatic castration-resistant prostate cancer progressing after docetaxel. In this Article, we report the secondary outcome of overall survival with mature follow-up, and an updated imaging biomarker analysis. We also report the outcomes of participants excluded due to ineligibility on gallium-68 [68Ga]Ga-PSMA-11 and 2-[18F]fluoro-2-deoxy-D-glucose (2-[18F]FDG) PET-CT. METHODS: TheraP was an open-label, randomised phase 2 trial at 11 centres in Australia. Eligible participants had metastatic castration-resistant prostate cancer progressing after docetaxel, and PET imaging with [68Ga]Ga-PSMA-11 and 2-[18F]FDG that showed prostate-specific membrane antigen (PSMA)-positive disease and no sites of metastatic disease with discordant 2-[18F]FDG-positive and PSMA-negative findings. Participants were randomly assigned (1:1) to treatment with [177Lu]Lu-PSMA-617 (every 6 weeks for a maximum of six cycles; starting at 8·5 GBq, decreasing by 0.5 GBq to 6·0 GBq for the sixth cycle) versus cabazitaxel (20 mg/m2 every 3 weeks, maximum of ten cycles). Overall survival was analysed by intention-to-treat and summarised as restricted mean survival time (RMST) to account for non-proportional hazards, with a 36-month restriction time corresponding to median follow-up. This trial is registered with ClinicalTrials.gov, NCT03392428, and is complete. FINDINGS: 291 men were registered from Feb 6, 2018, to Sept 3, 2019; after study imaging, 200 were eligible and randomly assigned to treatment with [177Lu]Lu-PSMA-617 (n=99) or cabazitaxel (n=101). After completing study treatment, 20 (20%) participants assigned to cabazitaxel and 32 (32%) assigned to [177Lu]Lu-PSMA-617 were subsequently treated with the alternative regimen. After a median follow-up of 35·7 months (IQR 31·1 to 39·2), 77 (78%) participants had died in the [177Lu]Lu-PSMA-617 group and 70 (69%) participants had died in the cabazitaxel group. Overall survival was similar among those assigned to [177Lu]Lu-PSMA-617 versus those assigned to cabazitaxel (RMST 19·1 months [95% CI 16·9 to 21·4] vs 19·6 months [17·4 to 21·8]; difference -0·5 months [95% CI -3·7 to 2·7]; p=0·77). No additional safety signals were identified with the longer follow-up in this analysis. 80 (27%) of 291 men who were registered after initial eligibility screening were excluded after [68Ga]Ga-PSMA-11 and 2-[18F]FDG PET. In the 61 of these men with follow-up available, RMST was 11·0 months (95% CI 9·0 to 13·1). INTERPRETATION: These results support the use of [177Lu]Lu-PSMA-617 as an alternative to cabazitaxel for PSMA-positive metastatic castration-resistant prostate cancer progressing after docetaxel. We did not find evidence that overall survival differed between the randomised groups. Median overall survival was shorter for men who were excluded because of low PSMA expression or 2-[18F]FDG-discordant disease. FUNDING: Australian and New Zealand Urogenital and Prostate Cancer Trials Group, Prostate Cancer Foundation of Australia, Endocyte (a Novartis company), Australian Nuclear Science and Technology Organization, Movember, It's a Bloke Thing, CAN4CANCER, and The Distinguished Gentleman's Ride.


Asunto(s)
Radioisótopos de Galio , Neoplasias de la Próstata Resistentes a la Castración , Masculino , Humanos , Resultado del Tratamiento , Docetaxel/uso terapéutico , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/radioterapia , Tomografía Computarizada por Tomografía de Emisión de Positrones , Fluorodesoxiglucosa F18 , Australia , Antígeno Prostático Específico
6.
Lancet Oncol ; 25(5): 563-571, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38621400

RESUMEN

BACKGROUND: Enzalutamide and lutetium-177 [177Lu]Lu-prostate-specific membrane antigen (PSMA)-617 both improve overall survival in patients with metastatic castration-resistant prostate cancer. Androgen and PSMA receptors have a close intracellular relationship, with data suggesting complementary benefit if targeted concurrently. In this study, we assessed the activity and safety of enzalutamide plus adaptive-dosed [177Lu]Lu-PSMA-617 versus enzalutamide alone as first-line treatment for metastatic castration-resistant prostate cancer. METHODS: ENZA-p was an open-label, randomised, controlled phase 2 trial done at 15 hospitals in Australia. Participants were men aged 18 years or older with metastatic castration-resistant prostate cancer not previously treated with docetaxel or androgen receptor pathway inhibitors for metastatic castration-resistant prostate cancer, gallium-68 [68Ga]Ga-PSMA-PET-CT (PSMA-PET-CT) positive disease, Eastern Cooperative Oncology Group performance status of 0-2, and at least two risk factors for early progression on enzalutamide. Participants were randomly assigned (1:1) by a centralised, web-based system using minimisation with a random component to stratify for study site, disease burden, use of early docetaxel, and previous treatment with abiraterone acetate. Patients were either given oral enzalutamide 160 mg daily alone or with adaptive-dosed (two or four doses) intravenous 7·5 GBq [177Lu]Lu-PSMA-617 every 6-8 weeks dependent on an interim PSMA-PET-CT (week 12). The primary endpoint was prostate-specific antigen (PSA) progression-free survival, defined as the interval from the date of randomisation to the date of first evidence of PSA progression, commencement of non-protocol anticancer therapy, or death. The analysis was done in the intention-to-treat population, using stratified Cox proportional hazards regression. This trial is registered with ClinicalTrials.gov, NCT04419402, and participant follow-up is ongoing. FINDINGS: 162 participants were randomly assigned between Aug 17, 2020, and July 26, 2022. 83 men were assigned to the enzalutamide plus [177Lu]Lu-PSMA-617 group, and 79 were assigned to the enzalutamide group. Median follow-up in this interim analysis was 20 months (IQR 18-21), with 32 (39%) of 83 patients in the enzalutamide plus [177Lu]Lu-PSMA-617 group and 16 (20%) of 79 patients in the enzalutamide group remaining on treatment at the data cutoff date. Median age was 71 years (IQR 64-76). Median PSA progression-free survival was 13·0 months (95% CI 11·0-17·0) in the enzalutamide plus [177Lu]Lu-PSMA-617 group and 7·8 months (95% CI 4·3-11·0) in the enzalutamide group (hazard ratio 0·43, 95% CI 0·29-0·63, p<0·0001). The most common adverse events (all grades) were fatigue (61 [75%] of 81 patients), nausea (38 [47%]), and dry mouth (32 [40%]) in the enzalutamide plus [177Lu]Lu-PSMA-617 group and fatigue (55 [70%] of 79), nausea (21 [27%]), and constipation (18 [23%]) in the enzalutamide group. Grade 3-5 adverse events occurred in 32 (40%) of 81 patients in the enzalutamide plus [177Lu]Lu-PSMA-617 group and 32 (41%) of 79 patients in the enzalutamide group. Grade 3 events that occurred only in the enzalutamide plus [177Lu]Lu-PSMA-617 group included anaemia (three [4%] of 81 participants) and decreased platelet count (one [1%] participant). No grade 4 or 5 events were attributed to treatment on central review in either group. INTERPRETATION: The addition of [177Lu]Lu-PSMA-617 to enzalutamide improved PSA progression-free survival providing evidence of enhanced anticancer activity in patients with metastatic castration-resistant prostate cancer with risk factors for early progression on enzalutamide and warrants further evaluation of the combination more broadly in metastatic prostate cancer. FUNDING: Prostate Cancer Research Alliance (Movember and Australian Federal Government), St Vincent's Clinic Foundation, GenesisCare, Roy Morgan Research, and Endocyte (a Novartis company).


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Benzamidas , Dipéptidos , Compuestos Heterocíclicos con 1 Anillo , Lutecio , Nitrilos , Feniltiohidantoína , Neoplasias de la Próstata Resistentes a la Castración , Humanos , Masculino , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/patología , Neoplasias de la Próstata Resistentes a la Castración/mortalidad , Feniltiohidantoína/administración & dosificación , Feniltiohidantoína/uso terapéutico , Feniltiohidantoína/análogos & derivados , Anciano , Dipéptidos/uso terapéutico , Dipéptidos/administración & dosificación , Dipéptidos/efectos adversos , Compuestos Heterocíclicos con 1 Anillo/uso terapéutico , Compuestos Heterocíclicos con 1 Anillo/administración & dosificación , Compuestos Heterocíclicos con 1 Anillo/efectos adversos , Persona de Mediana Edad , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Antígeno Prostático Específico/sangre , Supervivencia sin Progresión , Radioisótopos/uso terapéutico , Anciano de 80 o más Años , Radiofármacos
7.
Small ; 20(4): e2305186, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37649152

RESUMEN

Nanopore sensing has been successfully used to characterize biological molecules with single-molecule resolution based on the resistive pulse sensing approach. However, its use in nanoparticle characterization has been constrained by the need to tailor the nanopore aperture size to the size of the analyte, precluding the analysis of heterogeneous samples. Additionally, nanopore sensors often require the use of high salt concentrations to improve the signal-to-noise ratio, which further limits their ability to study a wide range of nanoparticles that are unstable at high ionic strength. Here, a new paradigm in nanopore research that takes advantage of a polymer electrolyte system to comprise a conductive pulse sensing approach is presented. A finite element model is developed to explain the conductive pulse signals observed and compare these results with experiments. This system enables the analytical characterization of heterogeneous nanoparticle mixtures at low ionic strength . Furthermore, the wide applicability of the method is demonstrated by characterizing metallic nanospheres of varied sizes, plasmonic nanostars with various degrees of branching, and protein-based spherical nucleic acids with different oligonucleotide loadings. This system will complement the toolbox of nanomaterials characterization techniques to enable real-time optimization workflow for engineering a wide range of nanomaterials.


Asunto(s)
Nanopartículas , Nanoporos , Ácidos Nucleicos , Proteínas , Nanotecnología
8.
Chemphyschem ; : e202400626, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39024523

RESUMEN

Self-assembled monolayers (SAMs) are emerging as platform technology for a myriad of applications, yet they still possess varied spatial stability and predictability issues as their properties are heavily dependent on subtle structural features. Reducing entropy within such a system serves as one of many potential solutions to increase order and therefore coherence/precision in measured properties. Here we explore controlled thermal annealing to improve edge disorders in SAMs and significantly reduce data variance. Using both odd- and even-numbered n-alkanethiol SAMs on Au, we observe statistically significant difference in the contact angles between edge and center. Thermal annealing at 40°C significantly narrows differences between edges and centre of the SAM, albeit with significant reduction in the parity dependent odd-even effect. This study provides a pathway to improve SAMs consistency through minimal external perturbation as reflected by the minimization of odd-even effect as SAMs become increasingly ordered.

9.
PLoS Comput Biol ; 19(3): e1010967, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36913404

RESUMEN

BACKGROUND: Pneumonia remains a leading cause of hospitalization and death among young children worldwide, and the diagnostic challenge of differentiating bacterial from non-bacterial pneumonia is the main driver of antibiotic use for treating pneumonia in children. Causal Bayesian networks (BNs) serve as powerful tools for this problem as they provide clear maps of probabilistic relationships between variables and produce results in an explainable way by incorporating both domain expert knowledge and numerical data. METHODS: We used domain expert knowledge and data in combination and iteratively, to construct, parameterise and validate a causal BN to predict causative pathogens for childhood pneumonia. Expert knowledge elicitation occurred through a series of group workshops, surveys and one-on-one meetings involving 6-8 experts from diverse domain areas. The model performance was evaluated based on both quantitative metrics and qualitative expert validation. Sensitivity analyses were conducted to investigate how the target output is influenced by varying key assumptions of a particularly high degree of uncertainty around data or domain expert knowledge. RESULTS: Designed to apply to a cohort of children with X-ray confirmed pneumonia who presented to a tertiary paediatric hospital in Australia, the resulting BN offers explainable and quantitative predictions on a range of variables of interest, including the diagnosis of bacterial pneumonia, detection of respiratory pathogens in the nasopharynx, and the clinical phenotype of a pneumonia episode. Satisfactory numeric performance has been achieved including an area under the receiver operating characteristic curve of 0.8 in predicting clinically-confirmed bacterial pneumonia with sensitivity 88% and specificity 66% given certain input scenarios (i.e., information that is available and entered into the model) and trade-off preferences (i.e., relative weightings of the consequences of false positive versus false negative predictions). We specifically highlight that a desirable model output threshold for practical use is very dependent upon different input scenarios and trade-off preferences. Three commonly encountered scenarios were presented to demonstrate the potential usefulness of the BN outputs in various clinical pictures. CONCLUSIONS: To our knowledge, this is the first causal model developed to help determine the causative pathogen for paediatric pneumonia. We have shown how the method works and how it would help decision making on the use of antibiotics, providing insight into how computational model predictions may be translated to actionable decisions in practice. We discussed key next steps including external validation, adaptation and implementation. Our model framework and the methodological approach can be adapted beyond our context to broad respiratory infections and geographical and healthcare settings.


Asunto(s)
Antibacterianos , Neumonía , Humanos , Teorema de Bayes , Encuestas y Cuestionarios , Australia
10.
Psychooncology ; 33(1): e6265, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38072641

RESUMEN

OBJECTIVES: The number of colorectal cancer (CRC) survivors is increasing and current models of survivorship care are unsustainable. There is a drive to implement alternative models of care including shared care between general practitioners (GPs) and hospital-based providers. The primary objective of this study was to explore perspectives on facilitators and barriers to shared care. The secondary objective was to explore experiences of telehealth-delivered care. METHOD: Qualitative data were collected via semi-structured interviews with participants in the Shared Care for Colorectal Cancer Survivors (SCORE) randomised controlled trial. Interviews explored patient experiences of usual and shared survivorship care during the SCORE trial. In response to the COVID pandemic, participant experiences of telehealth appointments were also explored. Interviews were recorded and transcribed for thematic analysis. RESULTS: Twenty survivors of CRC were interviewed with an even number in the shared and usual care arms; 14 (70%) were male. Facilitators to shared care included: good relationships with GPs; convenience of GPs; good communication between providers; desire to reduce public health system pressures. Barriers included: poor communication between clinicians; inaccessibility of GPs; beliefs about GP capacity; and a preference for follow-up care with the hospital after positive treatment experiences. Participants also commonly expressed a preference for telehealth-based follow-up when there was no need for a clinical examination. CONCLUSIONS: This is one of few studies that have explored patient experiences with shared and telehealth-based survivorship care. Findings can guide the implementation of these models, particularly around care coordination, communication, preparation, and personalised pathways of care.


Asunto(s)
Supervivientes de Cáncer , Neoplasias Colorrectales , Telemedicina , Femenino , Humanos , Masculino , Neoplasias Colorrectales/terapia , Sobrevivientes , Supervivencia , Investigación Cualitativa , Ensayos Clínicos Controlados Aleatorios como Asunto
11.
BMC Med Res Methodol ; 24(1): 120, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38802749

RESUMEN

BACKGROUND: To describe the methodology for conducting the CalScope study, a remote, population-based survey launched by the California Department of Public Health (CDPH) to estimate SARS-CoV-2 seroprevalence and understand COVID-19 disease burden in California. METHODS: Between April 2021 and August 2022, 666,857 randomly selected households were invited by mail to complete an online survey and at-home test kit for up to one adult and one child. A gift card was given for each completed survey and test kit. Multiple customized REDCap databases were used to create a data system which provided task automation and scalable data management through API integrations. Support infrastructure was developed to manage follow-up for participant questions and a communications plan was used for outreach through local partners. RESULTS: Across 3 waves, 32,671 out of 666,857 (4.9%) households registered, 6.3% by phone using an interactive voice response (IVR) system and 95.7% in English. Overall, 25,488 (78.0%) households completed surveys, while 23,396 (71.6%) households returned blood samples for testing. Support requests (n = 5,807) received through the web-based form (36.3%), by email (34.1%), and voicemail (29.7%) were mostly concerned with the test kit (31.6%), test result (26.8%), and gift card (21.3%). CONCLUSIONS: Ensuring a well-integrated and scalable data system, responsive support infrastructure for participant follow-up, and appropriate academic and local health department partnerships for study management and communication allowed for successful rollout of a large population-based survey. Remote data collection utilizing online surveys and at-home test kits can complement routine surveillance data for a state health department.


Asunto(s)
COVID-19 , Pruebas con Sangre Seca , SARS-CoV-2 , Humanos , COVID-19/epidemiología , COVID-19/diagnóstico , Estudios Seroepidemiológicos , California/epidemiología , SARS-CoV-2/inmunología , Pruebas con Sangre Seca/métodos , Pruebas con Sangre Seca/estadística & datos numéricos , Adulto , Encuestas y Cuestionarios , Masculino , Femenino , Niño , Persona de Mediana Edad , Adolescente
12.
J Chem Phys ; 160(2)2024 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-38189602

RESUMEN

Monoolein-based liquid crystal phases are established media that are researched for various biological applications, including drug delivery. While water is the most common solvent for self-assembly, some ionic liquids (ILs) can support lipidic self-assembly. However, currently, there is limited knowledge of IL-lipid phase behavior in ILs. In this study, the lyotropic liquid crystal phase behavior of monoolein was investigated in six protic ILs known to support amphiphile self-assembly, namely ethylammonium nitrate, ethanolammonium nitrate, ethylammonium formate, ethanolammonium formate, ethylammonium acetate, and ethanolammonium acetate. These ILs were selected to identify specific ion effects on monoolein self-assembly, specifically increasing the alkyl chain length of the cation or anion, the presence of a hydroxyl group in the cation, and varying the anion. The lyotropic liquid crystal phases with 20-80 wt. % of monoolein were characterized over a temperature range from 25 to 65 °C using synchrotron small angle x-ray scattering and cross-polarized optical microscopy. These results were used to construct partial phase diagrams of monoolein in each of the six protic ILs, with inverse hexagonal, bicontinuous cubic, and lamellar phases observed. Protic ILs containing the ethylammonium cation led to monoolein forming lamellar and bicontinuous cubic phases, while those containing the ethanolammonium cation formed inverse hexagonal and bicontinuous cubic phases. Protic ILs containing formate and acetate anions favored bicontinuous cubic phases across a broader range of protic IL concentrations than those containing the nitrate anion.

13.
AAPS PharmSciTech ; 25(4): 82, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600288

RESUMEN

Pressurized metered dose inhalers (pMDIs) require optimized formulations to provide stable, consistent lung delivery. This study investigates the feasibility of novel rugose lipid particles (RLPs) as potential drug carriers in pMDI formulations. The physical stability of RLPs was assessed in three different propellants: the established HFA-134a and HFA-227ea and the new low global-warming-potential (GWP) propellant HFO-1234ze. A feedstock containing DSPC and calcium chloride was prepared without pore forming agent to spray dry two RLP batches at inlet temperatures of 55 °C (RLP55) and 75 °C (RLP75). RLPs performance in pMDI formulations was compared to two reference samples that exhibit significantly different performance when suspended in propellants: well-established engineered porous particles and particles containing 80% trehalose and 20% leucine (80T20L). An accelerated stability study at 40 °C and relative humidity of 7% ± 5% was conducted over 3 months. At different time points, a shadowgraphic imaging technique was used to evaluate the colloidal stability of particles in pMDIs. Field emission electron microscopy with energy dispersive X-ray spectroscopy was used to evaluate the morphology and elemental composition of particles extracted from the pMDIs. After 2 weeks, all 80T20L formulations rapidly aggregated upon agitation and exhibited significantly inferior colloidal stability compared to the other samples. In comparison, both the RLP55 and RLP75 formulations, regardless of the propellant used, retained their rugose structure and demonstrated excellent suspension stability comparable with the engineered porous particles. The studied RLPs demonstrate great potential for use in pMDI formulations with HFA propellants and the next-generation low-GWP propellant HFO-1234ze.


Asunto(s)
Fluorocarburos , Hidrocarburos Fluorados , Inhaladores de Dosis Medida , Estudios de Factibilidad , Lípidos , Administración por Inhalación
14.
Pract Neurol ; 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39084908

RESUMEN

Retinal vasculopathy with cerebral leukoencephalopathy is a rare autosomal dominant genetic disorder due to mutation in the TREX1 gene and presents with both central nervous system (CNS) and other organ dysfunction. It is often misdiagnosed as demyelination or vasculitis based on imaging features, often with potentially harmful immunotherapy given unnecessarily. This report describes two sisters with progressive hemiparesis, retinal vasculopathy and hepatic dysfunction, one of whom was initially misdiagnosed and treated for cerebral vasculitis. Imaging showed extensive and asymmetric white matter lesions with persistent diffusion restriction and contrast enhancement. Extensive autoimmune and infectious investigations were unremarkable. Both patients had a novel heterozygous variant in the TREX1 gene, giving a diagnosis of retinal vasculopathy with cerebral leukoencephalopathy. Clinicians should consider this condition in atypical presentations of suspected demyelination or CNS vasculitis.

15.
Lancet Oncol ; 24(4): 323-334, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36990608

RESUMEN

BACKGROUND: The interim analysis of the ENZAMET trial of testosterone suppression plus either enzalutamide or standard nonsteroidal antiandrogen therapy showed an early overall survival benefit with enzalutamide. Here, we report the planned primary overall survival analysis, with the aim of defining the benefit of enzalutamide treatment in different prognostic subgroups (synchronous and metachronous high-volume or low-volume disease) and in those who received concurrent docetaxel. METHODS: ENZAMET is an international, open-label, randomised, phase 3 trial conducted at 83 sites (including clinics, hospitals, and university centres) in Australia, Canada, Ireland, New Zealand, the UK, and the USA. Eligible participants were males aged 18 years or older with metastatic, hormone-sensitive prostate adenocarcinoma evident on CT or bone scanning with 99mTc and an Eastern Cooperative Oncology Group performance status score of 0-2. Participants were randomly assigned (1:1), using a centralised web-based system and stratified by volume of disease, planned use of concurrent docetaxel and bone antiresorptive therapy, comorbidities, and study site, to receive testosterone suppression plus oral enzalutamide (160 mg once per day) or a weaker standard oral non-steroidal antiandrogen (bicalutamide, nilutamide, or flutamide; control group) until clinical disease progression or prohibitive toxicity. Testosterone suppression was allowed up to 12 weeks before randomisation and for up to 24 months as adjuvant therapy. Concurrent docetaxel (75 mg/m2 intravenously) was allowed for up to six cycles once every 3 weeks, at the discretion of participants and physicians. The primary endpoint was overall survival in the intention-to-treat population. This planned analysis was triggered by reaching 470 deaths. This study is registered with ClinicalTrials.gov, NCT02446405, ANZCTR, ACTRN12614000110684, and EudraCT, 2014-003190-42. FINDINGS: Between March 31, 2014, and March 24, 2017, 1125 participants were randomly assigned to receive non-steroidal antiandrogen (n=562; control group) or enzalutamide (n=563). The median age was 69 years (IQR 63-74). This analysis was triggered on Jan 19, 2022, and an updated survival status identified a total of 476 (42%) deaths. After a median follow-up of 68 months (IQR 67-69), the median overall survival was not reached (hazard ratio 0·70 [95% CI 0·58-0·84]; p<0·0001), with 5-year overall survival of 57% (0·53-0·61) in the control group and 67% (0·63-0·70) in the enzalutamide group. Overall survival benefits with enzalutamide were consistent across predefined prognostic subgroups and planned use of concurrent docetaxel. The most common grade 3-4 adverse events were febrile neutropenia associated with docetaxel use (33 [6%] of 558 in the control group vs 37 [6%] of 563 in the enzalutamide group), fatigue (four [1%] vs 33 [6%]), and hypertension (31 [6%] vs 59 [10%]). The incidence of grade 1-3 memory impairment was 25 (4%) versus 75 (13%). No deaths were attributed to study treatment. INTERPRETATION: The addition of enzalutamide to standard of care showed sustained improvement in overall survival for patients with metastatic hormone-sensitive prostate cancer and should be considered as a treatment option for eligible patients. FUNDING: Astellas Pharma.


Asunto(s)
Antagonistas de Andrógenos , Neoplasias de la Próstata , Masculino , Humanos , Anciano , Antagonistas de Andrógenos/efectos adversos , Docetaxel , Testosterona , Nivel de Atención , Neoplasias de la Próstata/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos
16.
Anal Chem ; 95(21): 8258-8266, 2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-37191580

RESUMEN

Scanning electrochemical cell microscopy (SECCM) maps the electrochemical activity of a surface with nanoscale resolution using an electrolyte-filled nanopipette. The meniscus at the end of the pipet is sequentially placed at an array of locations across the surface, forming a series of nanometric electrochemical cells where the current-voltage response is measured. Quantitative interpretation of these responses typically employs numerical modeling to solve the coupled equations of transport and electron transfer, which require costly software or self-written code. Expertise and time are required to build and solve numerical models, which must be rerun for each new experiment. In contrast, algebraic expressions directly relate the current response to physical parameters. They are simpler to use, faster to calculate, and can provide greater insight but frequently require simplifying assumptions. In this work, we provide algebraic expressions for current and concentration distributions in SECCM experiments, which are formulated by approximating the pipet and meniscus using 1-D spherical coordinates. Expressions for the current and concentration distributions as a function of experimental parameters and in various conditions (steady state and time dependent, diffusion limited, and including migration) all show excellent agreement with numerical simulations employing a full geometry. Uses of the analytical expressions include determination of expected currents in experiments and quantifying electron-transfer rate constants in SECCM experiments.

17.
PLoS Pathog ; 17(1): e1008299, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33465134

RESUMEN

Host resistance against intracellular pathogens requires a rapid IFN-γ mediated immune response. We reveal that T-bet-dependent production of IFN-γ is essential for the maintenance of inflammatory DCs at the site of infection with a common protozoan parasite, Toxoplasma gondii. A detailed analysis of the cellular sources for T-bet-dependent IFN-γ identified that ILC1s and to a lesser degree NK, but not TH1 cells, were involved in the regulation of inflammatory DCs via IFN-γ. Mechanistically, we established that T-bet dependent innate IFN-γ is critical for the induction of IRF8, an essential transcription factor for cDC1s. Failure to upregulate IRF8 in DCs resulted in acute susceptibility to T. gondii infection. Our data identifies that T-bet dependent production of IFN-γ by ILC1 and NK cells is indispensable for host resistance against intracellular infection via maintaining IRF8+ inflammatory DCs at the site of infection.


Asunto(s)
Células Dendríticas/inmunología , Inmunidad Innata/inmunología , Interferón gamma/metabolismo , Células Asesinas Naturales/inmunología , Linfocitos/inmunología , Proteínas de Dominio T Box/metabolismo , Toxoplasma/inmunología , Toxoplasmosis/inmunología , Animales , Células Dendríticas/metabolismo , Células Dendríticas/microbiología , Femenino , Factores Reguladores del Interferón/fisiología , Células Asesinas Naturales/metabolismo , Células Asesinas Naturales/microbiología , Linfocitos/metabolismo , Linfocitos/microbiología , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas de Dominio T Box/genética , Toxoplasma/metabolismo , Toxoplasmosis/metabolismo , Toxoplasmosis/microbiología
18.
Blood ; 138(3): 273-282, 2021 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-34292325

RESUMEN

Posttransplant cyclophosphamide (PTCy) graft-versus-host disease (GVHD) prophylaxis has enabled haploidentical (Haplo) transplantation to be performed with results similar to those after matched unrelated donor (MUD) transplantation with traditional prophylaxis. The relative value of transplantation with MUD vs Haplo donors when both groups receive PTCy/calcineurin inhibitor/mycophenolate GVHD prophylaxis is not known. We compared outcomes after 2036 Haplo and 284 MUD transplantations with PTCy GVHD prophylaxis for acute leukemia or myelodysplastic syndrome in adults from 2011 through 2018. Cox regression models were built to compare outcomes between donor types. Recipients of myeloablative and reduced-intensity regimens were analyzed separately. Among recipients of reduced-intensity regimens, 2-year graft failure (3% vs 11%), acute grades 2 to 4 GVHD (hazards ratio [HR], 0.70; P = .022), acute grades 3 and 4 GVHD (HR, 0.41; P = .016), and nonrelapse mortality (HR, 0.43; P = .0008) were lower after MUD than with Haplo donor transplantation. Consequently, disease-free (HR, 0.74; P = .008; 55% vs 41%) and overall (HR, 0.65; P = .001; 67% vs 54%) survival were higher with MUD than with Haplo transplants. Among recipients of myeloablative regimens, day-100 platelet recovery (95% vs 88%) was higher and grades 3 and 4 acute (HR, 0.39; P = .07) and chronic GVHD (HR, 0.66; P = .05) were lower after MUD than with Haplo donor transplantation. There were no differences in graft failure, relapse, nonrelapse mortality, and disease-free and overall survival between donor types with myeloablative conditioning regimens. These data extend and confirm the importance of donor-recipient HLA matching for allogeneic transplantation. A MUD is the preferred donor, especially for transplantations with reduced-intensity conditioning regimens.


Asunto(s)
Ciclofosfamida/uso terapéutico , Enfermedad Injerto contra Huésped/prevención & control , Trasplante de Células Madre Hematopoyéticas/métodos , Inmunosupresores/uso terapéutico , Leucemia Mieloide Aguda/terapia , Síndromes Mielodisplásicos/terapia , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Acondicionamiento Pretrasplante , Trasplante Haploidéntico/métodos , Trasplante Homólogo/métodos , Resultado del Tratamiento , Donante no Emparentado
19.
BMC Cancer ; 23(1): 180, 2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36814222

RESUMEN

BACKGROUND: Advanced gastro-oesophageal cancer (AGOC) carries a poor prognosis. No standard of care treatment options are available after first and second-line therapies. Regorafenib is an oral multi-targeted tyrosine kinase inhibitor targeting angiogenic, stromal, and oncogenic receptor tyrosine kinases. Regorafenib 160 mg daily prolonged progression free survival compared to placebo (INTEGRATE, phase 2). Regorafenib 80 mg daily in combination with nivolumab 3 mg/kg showed promising objective response rates (REGONIVO). METHODS/DESIGN: INTEGRATE II (INTEGRATE IIa and IIb) platform comprises two international phase III randomised controlled trials (RCT) with 2:1 randomisation in favor of experimental intervention. INTEGRATE IIa (double-blind) compares regorafenib 160 mg daily on days 1 to 21 of each 28-day cycle to placebo. INTEGRATE IIb (open label) compares REGONIVO, regorafenib 90 mg days 1 to 21 in combination with intravenous nivolumab 240 mg days 1 and 15 each 28-day cycle with investigator's choice of chemotherapy (control). Treatment continues until disease progression or intolerable adverse events as per protocol. Eligible participants include adults with AGOC who have failed two or more lines of treatment. Stratification is by location of tumour (INTEGRATE IIa only), geographic region, prior VEGF inhibitor and prior immunotherapy use (INTEGRATE IIb only). Primary endpoint is overall survival. Secondary endpoints are progression free survival, objective response rate, quality of life, and safety. Tertiary/correlative objectives include biomarker and pharmacokinetic evaluation. DISCUSSION: INTEGRATE II provides a platform to evaluate the clinical utility of regorafenib alone, as well as regorafenib in combination with nivolumab in treatment of participants with refractory AGOC. TRIAL REGISTRATION: INTEGRATE IIa prospectively registered 1 April 2016 Australia New Zealand Clinical Trial Registry: ACTRN12616000420448 (ClinicalTrials.gov NCT02773524). INTEGRATE IIb prospectively registered 10 May 2021 ClinicalTrials.gov: NCT04879368.


Asunto(s)
Neoplasias Esofágicas , Neoplasias Gástricas , Adulto , Humanos , Nivolumab/uso terapéutico , Piridinas/uso terapéutico , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Esofágicas/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica , Método Doble Ciego , Ensayos Clínicos Controlados Aleatorios como Asunto
20.
Br J Dermatol ; 189(Suppl 1): i3-i10, 2023 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-37903072

RESUMEN

Immune checkpoint inhibitors (ICIs) have revolutionized treatment strategies in the field of oncology. Their favourable outcomes in terms of efficacy and side-effect profile can be thwarted by the development of immune-related adverse events (irAEs). Cutaneous irAEs are relatively common in patients undergoing immunotherapy and include common inflammatory dermatoses (e.g. eczematous, psoriasiform and lichenoid phenotypes), maculopapular eruptions, pruritus and immunobullous disorders. Most of these reactions can be managed without ICIs having to be stopped completely; however, there are some life-threatening toxicities that dermatologists and oncologists should be aware of. In this review, we focus on how to recognize the commonly associated cutaneous irAEs, touching upon rarer reactions and red flags; finally, we provide guidance on their management.


Asunto(s)
Exantema , Neoplasias , Enfermedades de la Piel , Humanos , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Neoplasias/tratamiento farmacológico , Enfermedades de la Piel/inducido químicamente , Piel , Exantema/etiología , Inmunoterapia/efectos adversos
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