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1.
Brain ; 147(6): 2169-2184, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38662500

RESUMEN

Approximately 22% of Alzheimer's disease (AD) patients suffer from seizures, and the co-occurrence of seizures and epileptiform activity exacerbates AD pathology and related cognitive deficits, suggesting that seizures may be a targetable component of AD progression. Given that alterations in neuronal excitatory:inhibitory (E:I) balance occur in epilepsy, we hypothesized that decreased markers of inhibition relative to those of excitation would be present in AD patients. We similarly hypothesized that in 5XFAD mice, the E:I imbalance would progress from an early stage (prodromal) to later symptomatic stages and be further exacerbated by pentylenetetrazol (PTZ) kindling. Post-mortem AD temporal cortical tissues from patients with or without seizure history were examined for changes in several markers of E:I balance, including levels of the inhibitory GABAA receptor, the sodium potassium chloride cotransporter 1 (NKCC1) and potassium chloride cotransporter 2 (KCC2) and the excitatory NMDA and AMPA type glutamate receptors. We performed patch-clamp electrophysiological recordings from CA1 neurons in hippocampal slices and examined the same markers of E:I balance in prodromal 5XFAD mice. We next examined 5XFAD mice at chronic stages, after PTZ or control protocols, and in response to chronic mTORC1 inhibitor rapamycin, administered following kindled seizures, for markers of E:I balance. We found that AD patients with comorbid seizures had worsened cognitive and functional scores and decreased GABAA receptor subunit expression, as well as increased NKCC1/KCC2 ratios, indicative of depolarizing GABA responses. Patch clamp recordings of prodromal 5XFAD CA1 neurons showed increased intrinsic excitability, along with decreased GABAergic inhibitory transmission and altered glutamatergic neurotransmission, indicating that E:I imbalance may occur in early disease stages. Furthermore, seizure induction in prodromal 5XFAD mice led to later dysregulation of NKCC1/KCC2 and a reduction in GluA2 AMPA glutamate receptor subunit expression, indicative of depolarizing GABA receptors and calcium permeable AMPA receptors. Finally, we found that chronic treatment with the mTORC1 inhibitor, rapamycin, at doses we have previously shown to attenuate seizure-induced amyloid-ß pathology and cognitive deficits, could also reverse elevations of the NKCC1/KCC2 ratio in these mice. Our data demonstrate novel mechanisms of interaction between AD and epilepsy and indicate that targeting E:I balance, potentially with US Food and Drug Administration-approved mTOR inhibitors, hold therapeutic promise for AD patients with a seizure history.


Asunto(s)
Enfermedad de Alzheimer , Ratones Transgénicos , Convulsiones , Animales , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/fisiopatología , Convulsiones/metabolismo , Convulsiones/fisiopatología , Ratones , Masculino , Humanos , Femenino , Pentilenotetrazol/toxicidad , Anciano , Modelos Animales de Enfermedad , Excitación Neurológica/efectos de los fármacos , Anciano de 80 o más Años
2.
Bioinformatics ; 39(5)2023 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-37137236

RESUMEN

MOTIVATION: There is a need for easily accessible implementations that measure the strength of both linear and non-linear relationships between metabolites in biological systems as an approach for data-driven network development. While multiple tools implement linear Pearson and Spearman methods, there are no such tools that assess distance correlation. RESULTS: We present here SIgned Distance COrrelation (SiDCo). SiDCo is a GUI platform for calculation of distance correlation in omics data, measuring linear and non-linear dependencies between variables, as well as correlation between vectors of different lengths, e.g. different sample sizes. By combining the sign of the overall trend from Pearson's correlation with distance correlation values, we further provide a novel "signed distance correlation" of particular use in metabolomic and lipidomic analyses. Distance correlations can be selected as one-to-one or one-to-all correlations, showing relationships between each feature and all other features one at a time or in combination. Additionally, we implement "partial distance correlation," calculated using the Gaussian Graphical model approach adapted to distance covariance. Our platform provides an easy-to-use software implementation that can be applied to the investigation of any dataset. AVAILABILITY AND IMPLEMENTATION: The SiDCo software application is freely available at https://complimet.ca/sidco. Supplementary help pages are provided at https://complimet.ca/sidco. Supplementary Material shows an example of an application of SiDCo in metabolomics.


Asunto(s)
Metabolómica , Programas Informáticos , Lipidómica , Distribución Normal , Tamaño de la Muestra
3.
Aust Crit Care ; 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38584063

RESUMEN

BACKGROUND: Patients admitted from the emergency department to the wards, who progress to a critically unwell state, may require expeditious admission to the intensive care unit. It can be argued that earlier recognition of such patients, to facilitate prompt transfer to intensive care, could be linked to more favourable clinical outcomes. Nevertheless, this can be clinically challenging, and there are currently no established evidence-based methods for predicting the need for intensive care in the future. OBJECTIVES: We aimed to analyse the emergency department data to describe the characteristics of patients who required an intensive care admission within 48 h of presentation. Secondly, we planned to test the feasibility of using this data to identify the associated risk factors for developing a predictive model. METHODS: We designed a retrospective case-control study. Cases were patients admitted to intensive care within 48 h of their emergency department presentation. Controls were patients who did not need an intensive care admission. Groups were matched based on age, gender, admission calendar month, and diagnosis. To identify the associated variables, we used a conditional logistic regression model. RESULTS: Compared to controls, cases were more likely to be obese, and smokers and had a higher prevalence of cardiovascular (39 [35.1%] vs 20 [18%], p = 0.004) and respiratory diagnoses (45 [40.5%] vs 25 [22.5%], p = 0.004). They received more medical emergency team reviews (53 [47.8%] vs 24 [21.6%], p < 0.001), and more patients had an acute resuscitation plan (31 [27.9%] vs 15 [13.5%], p = 0.008). The predictive model showed that having acute resuscitation plans, cardiovascular and respiratory diagnoses, and receiving medical emergency team reviews were strongly associated with having an intensive care admission within 48 h of presentation. CONCLUSIONS: Our study used emergency department data to provide a detailed description of patients who had an intensive care unit admission within 48 h of their presentation. It demonstrated the feasibility of using such data to identify the associated risk factors to develop a predictive model.

4.
Pediatr Res ; 93(5): 1226-1232, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-35974157

RESUMEN

BACKGROUND: The impact of different respiratory strategies at birth on the preterm lung is well understood; however, concerns have been raised that lung recruitment may impede cerebral haemodynamics. This study aims to examine the effect of three different ventilation strategies on carotid blood flow, carotid artery oxygen content and carotid oxygen delivery. METHODS: 124-127-day gestation apnoeic intubated preterm lambs studied as part of a larger programme primarily assessing lung injury were randomised to positive pressure ventilation with positive end-expiratory pressure (PEEP) 8 cmH2O (No-RM; n = 12), sustained inflation (SI; n = 15) or dynamic PEEP strategy (DynPEEP; maximum PEEP 14 or 20 cmH2O, n = 41) at birth, followed by 90 min of standardised ventilation. Haemodynamic data were continuously recorded, with intermittent arterial blood gas analysis. RESULTS: Overall carotid blood flow measures were comparable between strategies. Except for mean carotid blood flow that was significantly lower for the SI group compared to the No-RM and DynPEEP groups over the first 3 min (p < 0.0001, mixed effects model). Carotid oxygen content and oxygen delivery were similar between strategies. Maximum PEEP level did not alter cerebral haemodynamic measures. CONCLUSIONS: Although there were some short-term variations in cerebral haemodynamics between different PEEP strategies and SI, these were not sustained. IMPACT: Different pressure strategies to facilitate lung aeration at birth in preterm infants have been proposed. There is minimal information on the effect of lung recruitment on cerebral haemodynamics. This is the first study that compares the effect of sustained lung inflation and dynamic and static positive end-expiratory pressure on cerebral haemodynamics. We found that the different ventilation strategies did not alter carotid blood flow, carotid oxygen content or carotid oxygen delivery. This preclinical study provides some reassurance that respiratory strategies designed to focus on lung aeration at birth may not impact cerebral haemodynamics in preterm neonates.


Asunto(s)
Recien Nacido Prematuro , Pulmón , Recién Nacido , Humanos , Animales , Ovinos , Animales Recién Nacidos , Oveja Doméstica , Hemodinámica , Oxígeno , Arterias Carótidas
5.
Brain ; 145(1): 324-339, 2022 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-34264340

RESUMEN

The risk of seizures is 10-fold higher in patients with Alzheimer's disease than the general population, yet the mechanisms underlying this susceptibility and the effects of these seizures are poorly understood. To elucidate the proposed bidirectional relationship between Alzheimer's disease and seizures, we studied human brain samples (n = 34) from patients with Alzheimer's disease and found that those with a history of seizures (n = 14) had increased amyloid-ß and tau pathology, with upregulation of the mechanistic target of rapamycin (mTOR) pathway, compared with patients without a known history of seizures (n = 20). To establish whether seizures accelerate the progression of Alzheimer's disease, we induced chronic hyperexcitability in the five times familial Alzheimer's disease mouse model by kindling with the chemoconvulsant pentylenetetrazol and observed that the mouse model exhibited more severe seizures than the wild-type. Furthermore, kindled seizures exacerbated later cognitive impairment, Alzheimer's disease neuropathology and mTOR complex 1 activation. Finally, we demonstrated that the administration of the mTOR inhibitor rapamycin following kindled seizures rescued enhanced remote and long-term memory deficits associated with earlier kindling and prevented seizure-induced increases in Alzheimer's disease neuropathology. These data demonstrated an important link between chronic hyperexcitability and progressive Alzheimer's disease pathology and suggest a mechanism whereby rapamycin may serve as an adjunct therapy to attenuate progression of the disease.


Asunto(s)
Enfermedad de Alzheimer , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Animales , Modelos Animales de Enfermedad , Humanos , Diana Mecanicista del Complejo 1 de la Rapamicina , Ratones , Pentilenotetrazol/toxicidad , Convulsiones/metabolismo
6.
N Engl J Med ; 380(8): 711-719, 2019 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-30511879

RESUMEN

BACKGROUND: Patients with active cancer have an increased risk of venous thromboembolism, which results in substantial morbidity, mortality, and health care expenditures. The Khorana score (range, 0 to 6, with higher scores indicating a higher risk of venous thromboembolism) has been validated to identify patients with cancer at elevated risk for this complication and may help select those who could benefit from thromboprophylaxis. METHODS: We conducted a randomized, placebo-controlled, double-blind clinical trial assessing the efficacy and safety of apixaban (2.5 mg twice daily) for thromboprophylaxis in ambulatory patients with cancer who were at intermediate-to-high risk for venous thromboembolism (Khorana score, ≥2) and were initiating chemotherapy. The primary efficacy outcome was objectively documented venous thromboembolism over a follow-up period of 180 days. The main safety outcome was a major bleeding episode. RESULTS: Of the 574 patients who underwent randomization, 563 were included in the modified intention-to-treat analysis. Venous thromboembolism occurred in 12 of 288 patients (4.2%) in the apixaban group and in 28 of 275 patients (10.2%) in the placebo group (hazard ratio, 0.41; 95% confidence interval [CI], 0.26 to 0.65; P<0.001). In the modified intention-to-treat analysis, major bleeding occurred in 10 patients (3.5%) in the apixaban group and in 5 patients (1.8%) in the placebo group (hazard ratio, 2.00; 95% CI, 1.01 to 3.95; P = 0.046). During the treatment period, major bleeding occurred in 6 patients (2.1%) in the apixaban group and in 3 patients (1.1%) in the placebo group (hazard ratio, 1.89; 95% CI, 0.39 to 9.24). CONCLUSIONS: Apixaban therapy resulted in a significantly lower rate of venous thromboembolism than did placebo among intermediate-to-high-risk ambulatory patients with cancer who were starting chemotherapy. The rate of major bleeding episodes was higher with apixaban than with placebo. (Funded by the Canadian Institutes of Health Research and Bristol-Myers Squibb-Pfizer Alliance; AVERT ClinicalTrials.gov number, NCT02048865.).


Asunto(s)
Inhibidores del Factor Xa/uso terapéutico , Neoplasias/tratamiento farmacológico , Pirazoles/uso terapéutico , Piridonas/uso terapéutico , Tromboembolia Venosa/prevención & control , Administración Oral , Anciano , Antineoplásicos/uso terapéutico , Método Doble Ciego , Inhibidores del Factor Xa/efectos adversos , Femenino , Hemorragia/inducido químicamente , Humanos , Incidencia , Análisis de Intención de Tratar , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Neoplasias/complicaciones , Pirazoles/efectos adversos , Piridonas/efectos adversos , Factores de Riesgo , Tromboembolia Venosa/etiología
7.
J Reconstr Microsurg ; 38(8): 593-603, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34905783

RESUMEN

BACKGROUND: The free medial femoral condyle (MFC) bone flap is an attractive option for reconstruction of scaphoid nonunion utilizing vascularized bone to augment bony healing, especially in cases of failed prior treatment or osteonecrosis. This review aims to determine the role and reliability of the free MFC flap for treatment of scaphoid nonunion. METHODS: A search of electronic databases was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Articles examining free MFC bone flaps for treatment of scaphoid nonunion were included for analysis. Outcomes of interest included flap failure, postoperative union rate, time to union, carpal indices, functional outcomes, and complications. RESULTS: Twelve articles met the inclusion criteria. A total of 262 patients underwent free MFC flaps for treatment of scaphoid nonunion. The most common site of nonunion was the proximal pole of the scaphoid with 47% of patients receiving prior attempts at operative management. Overall bony union rate was 93.4% with a mean time to union of 15.6 weeks. There were no flap failures reported. Improvements in carpal indices including scapholunate (p < 0.0004), radiolunate (p < 0.004), lateral interscaphoid angles (p < 0.035), and revised carpal ratio height (p < 0.024) were seen postoperatively. Visual analog scale improved postoperatively from 6.5 to 2.3 (p < 0.015). Postoperative complications were observed in 69 cases (26.3%), with 27 patients (10.3%) requiring further operative intervention. However, no major donor or recipient site morbidity was appreciated. CONCLUSION: MFC flaps provide a highly versatile and reliable option for reconstruction of scaphoid nonunion with excellent bony union rates and acceptable complication rates. The present literature suggests that MFC reconstruction of scaphoid nonunion restores radiocarpal anatomy and improves wrist function without causing significant donor or recipient site morbidity.


Asunto(s)
Fracturas no Consolidadas , Colgajos Tisulares Libres , Hueso Escafoides , Trasplante Óseo , Fracturas no Consolidadas/cirugía , Humanos , Complicaciones Posoperatorias , Reproducibilidad de los Resultados , Estudios Retrospectivos , Hueso Escafoides/cirugía
8.
Health Info Libr J ; 39(4): 385-391, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36123955

RESUMEN

National Health Service (NHS) knowledge and library services in England are integrating digital advances into their systems and services. Health Education England (HEE) leads on the development of NHS library services. A key workstream focuses on (1) improving the infrastructure to enable discovery and management of digital knowledge resources; (2) collaborating with local teams to establish regional library management systems that are integrated with the new national discovery service for healthcare staff and learners. This article explores initiatives on resource discovery as well as the need for system-wide partnership working to ensure that biomedical knowledge in computable form is findable, accessible, interoperable and reusable. Low levels of health and digital literacy pose a significant barrier to using health information and accessing health services. A range of interventions are aimed at enhancing citizens' digital and health literacy skills. The education and life-long learning needs of the knowledge and library services workforce are considered. Working with CILIP and higher education institutions, HEE delivers a range of educational offers through its Learning Academy. As Artificial Intelligence and automation are implemented in health systems, knowledge and library staff form a crucial bridge between technology and those who use it.


Asunto(s)
Servicios de Biblioteca , Medicina Estatal , Humanos , Inteligencia Artificial , Inglaterra , Aprendizaje
9.
Am J Gastroenterol ; 116(6): 1124-1147, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-34003176

RESUMEN

Clostridioides difficile infection occurs when the bacterium produces toxin that causes diarrhea and inflammation of the colon. These guidelines indicate the preferred approach to the management of adults with C. difficile infection and represent the official practice recommendations of the American College of Gastroenterology. The scientific evidence for these guidelines was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation process. In instances where the evidence was not appropriate for Grading of Recommendations Assessment, Development, and Evaluation but there was consensus of significant clinical merit, key concept statements were developed using expert consensus. These guidelines are meant to be broadly applicable and should be viewed as the preferred, but not the only, approach to clinical scenarios.


Asunto(s)
Infecciones por Clostridium , Antibacterianos/uso terapéutico , Clostridioides difficile/aislamiento & purificación , Infecciones por Clostridium/diagnóstico , Infecciones por Clostridium/tratamiento farmacológico , Infecciones por Clostridium/prevención & control , Diarrea/tratamiento farmacológico , Diarrea/microbiología , Diarrea/prevención & control , Humanos , Inflamación/tratamiento farmacológico , Inflamación/microbiología , Inflamación/prevención & control , Recurrencia
10.
Inorg Chem ; 60(21): 16570-16583, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34662517

RESUMEN

The optical properties of coordination complexes with ligands containing nitrogen heterocycles have been extensively studied for decades. One subclass of these materials, metal complexes utilizing substituted pyrazines and quinoxalines as ligands, has been employed in a variety of photochemical applications ranging from photodynamic therapy to organic light-emitting diodes. A vast majority of this work focuses on characterization of the metal-to-ligand charge-transfer states in these metal complexes; however, literature reports rarely investigate the photophysics of the parent pyrazine or quinoxaline ligand or perform control experiments utilizing metal complexes that lack low-lying charge-transfer (CT) states in order to determine how metal-atom coordination influences the photophysical properties of the ligand. With this in mind, we examined the steady-state and time-resolved photophysics of 2,3-di(pyridin-2-yl)benzo[g]quinoxaline (dpb) and explored how the coordination of ZnX2 (X = Cl-, Br-, I-) affects the photophysical properties of dpb. In dpb, we find that the dominant mode of deactivation from the singlet excited state is intersystem crossing (ISC). Coordination of ZnX2 perturbs the relative energies of the ππ* and nπ* excited states of dpb, leading to drastically different rates of ISC as well as radiative and nonradiative decay in the [Zn(dpb)X2] complexes compared to dpb. These differences in the rates change the dominant singlet-excited-state decay pathway from ISC in dpb to a mixture of ISC and fluorescence in [Zn(dpb)Cl2] and [Zn(dpb)Br2] and to nonradiative decay in [Zn(dpb)I2]. Coordination of ZnX2 and the choice of the halide ligand also have profound effects on the rate constants for excited-state bimolecular reactions, including triplet-triplet annihilation and oxygen quenching. These results demonstrate that metal coordination, even in complexes lacking low-lying CT states, and the choice of the ancillary ligand can dramatically alter the photophysical properties of chromophores containing nitrogen heterocycles.

11.
J Hand Surg Am ; 46(11): 1032.e1-1032.e3, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33526296

RESUMEN

We report a case of medial femoral trochlea flap used for scaphoid proximal pole reconstruction, in which the transverse branch of the descending genicular artery was vestigial. The medial metaphyseal periosteal artery was clearly the dominant pedicle supplying the trochlear region. The flap was safely raised on the medial metaphyseal periosteal artery pedicle. The incidence of this uncommon presentation remains unknown and this anatomical variant is newly described.


Asunto(s)
Hueso Escafoides , Colgajos Quirúrgicos , Arterias , Fémur/diagnóstico por imagen , Fémur/cirugía , Humanos , Periostio
12.
Microsurgery ; 41(7): 666-670, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33932250

RESUMEN

Conventional grafts do not perform well in the treatment of large diaphyseal bone defects. Forearm nonunions are especially challenging due to complex biomechanical and kinematic demands. Free bone flaps may yield more predictable bony restoration in these cases, while keeping morbidity acceptable to the patient. We aim to illustrate one combination of flaps which can be used in these conditions. This article reports on a 23 year old patient with an 8 cm diaphyseal nonunion of the radius and a similar 7 cm defect of the ulna after infection of fracture fixation hardware. The radius was treated with a free fibular flap (FFF) and the ulna with a medial femoral condyle (MFC) flap in a staged procedure after initial debridement. The patient was followed up for 6 months without significant complications. Both flaps healed within 3 months, yet the MFC demonstrated faster bony incorporation. We attributed this to the spongious nature of the MFC flap compared to the thick cortical FFF. This case report hopes to illustrate one type of flap combination for extensive forearm bone defects. The selection and approach minimizes donor site morbidity to a single limb and possibly hastens bony union of the forearm.


Asunto(s)
Colgajos Tisulares Libres , Procedimientos de Cirugía Plástica , Adulto , Trasplante Óseo , Peroné/cirugía , Humanos , Radio (Anatomía)/cirugía , Cúbito , Adulto Joven
13.
Am Nat ; 195(4): 678-690, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32216673

RESUMEN

Life-history theory predicts that investment per offspring should correlate negatively with the quality of the environment that offspring are anticipated to encounter; parents may use their own experience as juveniles to predict this environment and may modulate offspring traits, such as growth capacity and initial size. We manipulated nutrient levels in the juvenile habitat of wild Atlantic salmon (Salmo salar) to investigate the hypothesis that the egg size that maximizes juvenile growth and survival depends on environmental quality. We also tested whether offspring traits were related to parental growth trajectory. Mothers that grew fast when young produced more offspring and smaller offspring than mothers that grew slowly to reach the same size. Despite their size disadvantage, offspring of faster-growing mothers grew faster than those of slower-growing mothers in all environments, counter to the expectation that they would be competitively disadvantaged. However, they had lower relative survival in environments where the density of older predatory/competitor fish was relatively high. These links between maternal (but not paternal) growth trajectory and offspring survival rate were independent of egg size, underscoring that mothers may be adjusting egg traits other than size to suit the environment their offspring are anticipated to face.


Asunto(s)
Tamaño Corporal , Ecosistema , Salmo salar/crecimiento & desarrollo , Animales , Femenino , Masculino , Óvulo/citología , Fenotipo , Conducta Predatoria , Salmo salar/fisiología
14.
Oncologist ; 25(1): e130-e137, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31506392

RESUMEN

BACKGROUND: Canada has an established publicly funded health care system with a complex drug approval and funding process. After proof of efficacy (POE; key publication/presentation) and before becoming publicly accessible, each drug undergoes a Health Canada approval process, a health technology assessment (HTA), a pricing negotiation, and finally individual provincial funding agreements. We quantified potential life-years lost during this process. METHODS: We analyzed drugs for advanced lung, breast, and colorectal cancer that underwent the HTA process between 2011 and 2016. Life-years lost were calculated by multiplying documented improvement in progression-free and overall survival, number of eligible patients, and time from POE to first public funding. For conservative calculation, we assumed all eligible patients in Canada had access at the time of first public funding, whereas in reality provinces fund at different time points. RESULTS: We analyzed 21 drugs. Of these, 15 have been funded publicly. The time from POE to first public funding ranged from 14.0 to 99.2 months (median 26.6 months). Total overall life-years lost from POE to first public funding were 39,067 (lung 32,367; breast 6,691). Progression-free life-years lost from POE to first public funding were 48,037 (lung 9,139, breast 15,827, colorectal 23,071). CONCLUSION: The number of potential life-years lost during the drug regulatory and funding process in Canada is substantial, largely driven by delays to funding of colorectal cancer drugs. Recognizing that interprovincial differences exist and that eligible patients may not all receive a given drug, if even a fraction does so, the impact of delays remains substantive. Collaborative national initiatives are required to address this major barrier to treatment access. IMPLICATIONS FOR PRACTICE: Patients may spend lengthy periods of time awaiting access to new and effective cancer drugs. Patients with private drug insurance or personal funds or who reside in certain Canadian provinces may obtain some drugs sooner than others, potentially creating a two-tiered access system. The cancer drug access and public funding system must be expedited to improve equity.


Asunto(s)
Aprobación de Drogas/economía , Costos de los Medicamentos , Control de Medicamentos y Narcóticos/economía , Canadá , Humanos
15.
Adv Funct Mater ; 30(28): 1910562, 2020 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-32684903

RESUMEN

The fabrication, molecular structure, and spectroscopy of a stable cholesteric liquid crystal platinum acetylide glass obtained from trans-Pt(PEt3)2(C≡C-C6H5-C≡N)(C≡C-C6H5-COO-Cholesterol), are described and designated as PE1-CN-Chol. Polarized optical microscopy, differential scanning calorimetry, and wide-angle X-ray scattering experiments show room temperature glassy/crystalline texture with crystal formation upon heating to 165 °C. Further heating results in conversion to cholesteric phase. Cooling to room temperature leads to the formation of a cholesteric liquid crystal glass. Scanning tunneling microscopy of a PE1-CN-Chol monolayer reveals self-assembly at the solid-liquid interface with an array of two molecules arranged in pairs, oriented head-to-head through the CN groups, giving rise to a lamella arrangement. The lamella structure obtained from molecular dynamics calculations shows a clear phase separation between the conjugated platinum acetylide and the hydrophobic cholesterol moiety with the lamellae separation distance being 4.0 nm. Ultrafast transient absorption and flash photolysis spectra of the glass show intersystem crossing to the triplet state occurring within 100 ps following excitation. The triplet decay time of the film compared to aerated and deoxygenated solutions is consistent with oxygen quenching at the film surface but not within the film. The high chromophore concentration, high glass thermal stability, and long triplet lifetime in air show that these materials have potential as nonlinear absorbing materials.

16.
Oncology ; 98(10): 669-679, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32599578

RESUMEN

Drug resistance is one of the most important factors limiting the success of systemic anticancer therapy in achieving cure or prolonged overall survival. In clinical practice, resistant disease describes cancer that is found to have progressed since the time of treatment initiation. The term "drug resistant" is often used synonymously with "progressive disease" when referring to a treated tumour. Stopping a treatment at the time of disease progression is the current dominant approach of clinical trial conduct; therefore, available data from clinical trials are routinely not able to provide any information that could challenge this concept of permanent drug resistance. However, drug rechallenge and treatment continuation beyond progression have emerged as potential strategies in the past decade, especially for molecularly targeted agents and immunotherapy. In this review we focussed on rechallenge strategies for chemotherapy, immune therapy and targeted therapy in the main types of cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias/tratamiento farmacológico , Ensayos Clínicos Fase II como Asunto , Ensayos Clínicos Fase III como Asunto , Resistencia a Antineoplásicos , Humanos , Estudios Observacionales como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Retrospectivos
17.
J Org Chem ; 85(1): 284-290, 2020 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-31132242

RESUMEN

The dipyrrolonaphthyridinedione (DPND) core can be readily converted into a series of acid-responsive quinazolinoindolizinoindolizinoquinazolines through a two-step route involving direct arylation followed by acid-catalyzed condensation. Unlike the majority of previously obtained DPNDs, these nonplanar dyes bearing eight fused rings are almost nonfluorescent, which is attributed to fast internal conversion relative to radiative decay and intersystem crossing.

18.
Phys Chem Chem Phys ; 22(21): 11915-11927, 2020 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-32409811

RESUMEN

Three new gold(i) alkynyl complexes (Au-ABTF(0-2)) containing a benzothiazole fluorenyl moiety, with either an organic phosphine or N-heterocyclic carbene as ancillary ligand, have been synthesized and photophysically characterized. All three complexes display highly structured ground-state absorption and luminescence spectra. Dual-luminescence is observed in all three complexes at room temperature in toluene after three freeze-pump-thaw cycles. The phosphine complexes (Au-ABTF(0-1)) exhibit similar photophysics with fluorescent quantum yields ∼0.40, triplet-state quantum yields ∼0.50, and fluorescent lifetimes ∼300 ps. The carbene complex Au-ABTF2 displays different behavior; having a fluorescent quantum yield of 0.23, a triplet-state quantum yield of 0.61, and a fluorescent lifetime near 200 ps, demonstrating that the ancillary ligand alters excited-state dynamics. The compounds exhibit strong (on the order of 105 M-1 cm-1) and positive excited-state absorption in both their singlet and triplet excited states spanning the visible region. Delayed fluorescence resulting from triplet-triplet annihilation is also observed in freeze-pump-thaw deaerated samples of all the complexes in toluene. DFT calculations (both static and time-resolved) agree with the photophysical data where phosphine complexes have slightly larger S1-T2 energy gaps (0.28 eV and 0.26 eV) relative to the carbene complex (0.21 eV). Comparison of the photophysical properties of Au-ABTF(0-2) to previously published dinuclear gold(i) complexes and mononuclear gold(i) aryl complexes bearing the same benzothiazole-2,7-fluorenyl moiety are made. Structure-property relationships regarding ancillary ligand, bridging moiety, and number of metal centers are drawn.

19.
Future Oncol ; 16(12): 749-762, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32228198

RESUMEN

Aim: Evaluate quality of life (QoL) in patients with advanced non-small cell lung cancer treated with second or third line nab-paclitaxel ± durvalumab. Patients & methods: Longitudinal QoL was assessed using Lung Cancer Symptom Scale, EuroQoL Five-Dimensions Five-Levels and European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire 30-item core. Results: QoL was generally stable through eight treatment cycles (both arms). Clinically meaningful improvement from baseline was noted in Lung Cancer Symptom Scale (overall constitutional score and three-item index [nab-paclitaxel + durvalumab]) and European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire 30-item core (global health status/QoL and emotional functioning [both arms] and pain [nab-paclitaxel + durvalumab]) analyses. EuroQoL Five-Dimensions Five-Levels domains were stable/improved or completely resolved at least once in 19-56% and 9-51% of patients, respectively. Conclusion: While QoL trends were promising, additional data are required to support these regimens in this setting.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Calidad de Vida , Adulto , Anciano , Anciano de 80 o más Años , Albúminas/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Paclitaxel/administración & dosificación , Retratamiento , Resultado del Tratamiento
20.
J Phys Chem A ; 124(11): 2113-2122, 2020 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-32068405

RESUMEN

In an effort to probe the influence of structural isomerism on the excited-state properties of a naphthalene-based donor-acceptor (D-A) system, four 1-naphthalenecarbonitrile compounds with amine substituents in the 2-, 3-, and 4-positions were synthesized and their photophysical properties were examined. Specifically, the molecules 2-dimethylamino-1-naphthalenecarbonitrile (2DA), 2-(1-piperidinyl)-1-naphthalenecarbonitrile (2P), 3-dimethylamino-1-naphthalenecarbonitrile (3DA), and 4-(1-piperidinyl)-1-naphthalenecarbonitrile (4P) were studied. The substitution position of the amine donor has a significant impact on both the ground-state absorption and excited-state properties of the complexes in toluene solution. The energy, band shape, and extinction coefficient of the ground-state absorption spectra are highly dependent on the substitution position of the amine donor. All of the derivatives exhibit fluorescence at room temperature. The fluorescence observed from 2DA, 2P, and 3DA demonstrates a vibronic structure with all three molecules possessing Stokes shifts on the order of 40 nm, whereas the fluorescence observed from 4P is broad and has a Stokes shift 2 times greater than the other derivatives. The fluorescence lifetimes, fluorescence quantum yields, and intersystem crossing quantum yields vary greatly with the substitution position of the amine donor. 2DA and 2P display intermediate fluorescence lifetimes (2.7 ns) and fluorescence quantum yields (0.20) while possessing the greatest intersystem quantum yield (0.80). 3DA has a much greater fluorescence lifetime (16.9 ns) and fluorescence quantum yield (0.82) at the expense of the intersystem crossing quantum yield (0.12). 4P has the shortest lifetime (0.53 ns), with the lowest fluorescence and intersystem crossing quantum yields (<0.05). The singlet-triplet energy gaps are nearly identical for 2DA, 2P, and 3DA with values on the order of 0.70 eV. This singlet-triplet gap is larger in 4P, with a calculated value of 0.94 eV. The triplet-triplet absorption spectra of 2DA, 2P, and 3DA are similar. Broad peaks in the UV and visible regions with maxima around 330 and 500 nm characterize all three spectra. The triplet excited-state extinction coefficient values for 3DA were found to be 1.5 times larger than those in 2DA and 2P. The triplet-triplet absorption spectrum of 4P is markedly different from the triplet-triplet absorption spectra of the other derivatives. The spectrum is broad, with the four local maxima observed at 374, 445, 624, and 774 nm. All four molecules display delayed fluorescence and laser-power-dependent triplet excited-state decay kinetics, indicating the involvement of triplet-triplet annihilation in the deactivation of the triplet excited states. Both the intrinsic triplet lifetimes and triplet-triplet annihilation rate constants were determined. These values are similar for all of the derivatives with triplet lifetimes on the order of 100 µs and diffusion-controlled rates of triplet-triplet annihilation.

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