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1.
Inorg Chem ; 63(11): 4947-4956, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38437618

RESUMEN

A series of photosensitizers comprised of both an inorganic and an organic chromophore are investigated in a joint synthetic, spectroscopic, and theoretical study. This bichromophoric design strategy provides a means by which to significantly increase the excited state lifetime by isolating the excited state away from the metal center following intersystem crossing. A variable bridging group is incorporated between the donor and acceptor units of the organic chromophore, and its influence on the excited state properties is explored. The Franck-Condon (FC) photophysics and subsequent excited state relaxation pathways are investigated with a suite of steady-state and time-resolved spectroscopic techniques in combination with scalar-relativistic quantum chemical calculations. It is demonstrated that the presence of an electronically conducting bridge that facilitates donor-acceptor communication is vital to generate long-lived (32 to 45 µs), charge-separated states with organic character. In contrast, when an insulating 1,2,3-triazole bridge is used, the excited state properties are dominated by the inorganic chromophore, with a notably shorter lifetime of 60 ns. This method of extending the lifetime of a molecular photosensitizer is, therefore, of interest for a range of molecular electronic devices and photophysical applications.

2.
Med J Aust ; 220(2): 80-90, 2024 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-38212673

RESUMEN

OBJECTIVES: To review the outcomes of immune checkpoint inhibitor (ICI) treatment of advanced cutaneous squamous cell carcinoma (CSCC) outside clinical trials. STUDY DESIGN: Retrospective observational study; review of patient records in fifteen Australian institutions. SETTING, PARTICIPANTS: All Australian adults with locally advanced or metastatic CSCC not amenable to curative surgery or radiotherapy treated with ICIs, 5 May 2017 - 23 May 2022, through a cemiplimab compassionate access scheme (Therapeutic Goods Administration Special Access Scheme) or who personally covered the cost of pembrolizumab prior to the start of the access scheme. MAIN OUTCOME MEASURES: Best overall response rate (ORR) according to standardised assessment criteria using the hierarchy: Response Evaluation Criteria in Solid Tumors (RECIST 1.1), the modified World Health Organization clinical response criteria, and the Positron Emission Tomography Response Criteria (PERCIST 1.0); overall and progression-free survival. RESULTS: A total of 286 people with advanced CSCC received ICI therapy during May 2017 - May 2022 (cemiplimab, 270; pembrolizumab, 16). Their median age was 75.2 years (range, 39.3-97.5 years) and 232 were men (81%); median follow-up time was 12.2 months (interquartile range, 5.5-20.5 months). Eighty-eight people (31%) were immunocompromised, 27 had autoimmune disease, and 59 of 277 (21%) had ECOG performance scores of 2 or 3. The ORR was 60% (166 of 278 evaluable patients): complete responses were recorded for 74 (27%) and partial responses for 92 patients (33%). Twelve-month overall survival was 78% (95% confidence interval [CI], 72-83%); progression-free survival was 65% (95% CI, 58-70%). Poorer ECOG performance status was associated with poorer overall survival (per unit: adjusted hazard ratio [aHR], 3.0; 95% CI, 2.0-4.3) and progression-free survival (aHR, 2.4; 95% CI, 1.8-3.3), as was being immunocompromised (overall: aHR, 1.8; 95% CI, 1.1-3.0; progression-free: aHR, 1.8; 95% CI, 1.2-2.7). Fifty-five people (19%) reported immune-related adverse events of grade 2 or higher; there were no treatment-related deaths. CONCLUSION: In our retrospective study, the effectiveness and toxicity of ICI therapy were similar to those determined in clinical trials. Our findings suggest that ICIs could be effective and well tolerated by people with advanced CSCC who are ineligible for clinical trials.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Cutáneas , Masculino , Adulto , Humanos , Anciano , Femenino , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/patología , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/patología , Estudios Retrospectivos , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Estudios de Cohortes , Australia/epidemiología
3.
Med Teach ; : 1-8, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38277134

RESUMEN

Peer-led assessment (PLA) has gained increasing prominence within health professions education as an effective means of engaging learners in the process of assessment writing and practice. Involving students in various stages of the assessment lifecycle, including item writing, quality assurance, and feedback, not only facilitates the creation of high-quality item banks with minimal faculty input but also promotes the development of students' assessment literacy and fosters their growth as teachers. The advantages of involving students in the generation of assessments are evident from a pedagogical standpoint, benefiting both students and faculty. However, faculty members may face uncertainty when it comes to implementing such approaches effectively. To address this concern, this paper presents twelve tips that offer guidance on important considerations for the successful implementation of peer-led assessment schemes in the context of health professions education.

4.
Aust J Rural Health ; 32(3): 569-581, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38629876

RESUMEN

OBJECTIVE: Cancer clinical trials (CCTs) provide access to emerging therapies and extra clinical care. We aimed to describe the volume and characteristics of CCTs available across Victoria, Australia, and identify factors associated with rural trial location. METHODS: Quantitative analysis of secondary data from Cancer Council Victoria's Clinical Trials Management Scheme dataset. DESIGN: A cross-sectional study design was used. SETTING: CCTs were available Victoria-wide in 2018. PARTICIPANTS: There were 1669 CCTs and 5909 CCT participants. MAIN OUTCOME MEASURES: Rural CCT location was assessed as a binary variable with categories of 'yes' (modified Monash [MM] categories 2-7) and 'no' (MM category 1). MM categories were determined from postcodes. The highest ('least rural') MM category was used for postcodes with multiple MM categories. RESULTS: Of 1669 CCTs, 168 (10.1%) were conducted in rural areas. Of 5909 CCT participants, 315 (5.3%) participated in rural CCTs. There were 526 CCTs (31.5%) with 1907 (32.3%) newly enrolled participants. Of 1892 newly enrolled participants with postcode data, 488 (25.8%) were rural residents. Of them, 368 (75.4%) participated in metropolitan CCTs. In a multivariable logistic regression analysis for all 1669 CCTs, odds of a rural rather than metropolitan CCT location were significantly (p-value <0.05) lower for early-phase than late-phase trials and non-solid than solid tumour trials but significantly (p-value <0.05) higher for non-industry than industry-sponsored trials. CONCLUSIONS: In Victoria, 10% of CCTs are at rural sites. Most rural-residing CCT participants travel to metropolitan sites, where there are more late-phase, non-solid-tumour and industry-sponsored trials. Approaches to increase the volume and variety of rural CCTs should be considered.


Asunto(s)
Ensayos Clínicos como Asunto , Neoplasias , Población Rural , Humanos , Victoria , Neoplasias/terapia , Estudios Transversales , Población Rural/estadística & datos numéricos , Femenino , Masculino , Servicios de Salud Rural/estadística & datos numéricos , Persona de Mediana Edad , Población Urbana/estadística & datos numéricos
5.
J Phys Chem A ; 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37310731

RESUMEN

The vibrational and electronic properties of six systematically altered donor-acceptor dyes were investigated with density functional theory (DFT), spectroscopy, and electrochemical techniques. The dyes incorporated a carbazole donor connected to a dithieno[3,2-b:2',3'-d]thiophene linker at either the C2 (m) or C3 (p) position. Indane-based acceptors contained either dimalononitrile (IndCN), ketone and malononitrile (InOCN) or diketone (IndO) electron accepting groups. Molecular geometries modeled by DFT using the BLYP functional and def2-TZVP basis set showed planar geometries containing large, extended π-systems and produced Raman spectra consistent with the experimental data. Electronic absorption spectra had transitions with π-π* character at wavelengths below 325 nm and a charge transfer (CT) transition region from 500 to 700 nm. The peak wavelength was dependent on the donor and acceptor architecture, with each modulating the HOMO and LUMO levels, respectively, supported by TD-DFT estimates using the LC-ωPBE* functional and 6-31g(d) basis set. The compounds showed emission in solution with quantum yields ranging from 0.004 to 0.6 and lifetimes of less than 2 ns. These were assigned to either π-π* or CT emissive states. Signals attributed to CT states exhibited positive solvatochromism and thermochromism. The spectral emission behavior of each compound trended with the acceptor unit moieties, where malononitrile units lead to greater π-π* character and ketones exhibited greater CT character.

6.
J Phys Chem A ; 126(34): 5681-5691, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35998577

RESUMEN

The geometric and spectroscopic properties of four cationic N-aryl-2,4,6-triphenylpyridinium-based donor-acceptor dyes─1-[4-(9H-carbazol-9-yl)phenyl]-2,4,6-triphenylpyridinium, 1-[4-(N,N-diphenylamino)phenyl]-2,4,6-triphenylpyridinium, 1-(9-phenyl-9H-carbazol-3-yl)-2,4,6-triphenylpyridinium, and 1-(9-ethyl-9H-carbazol-3-yl)-2,4,6-triphenylpyridinium─are reported. The four dyes exhibited a twisted, quasi-perpendicular geometry about the central donor-acceptor bond, shown by X-ray crystallography and supported by Raman spectroscopy and DFT calculations. The electronic absorption spectra show weak charge transfer (CT) transitions at about 400 nm (ε ∼ 3000 L mol-1 cm-1). Time dependent (TD) DFT supported the nature of the CT transition, displaying an 89-97% shift in electron density from the donor to the acceptor upon electronic excitation. Excited state geometry calculations revealed significant geometry changes upon electronic excitation. Enhancement of vibrational modes attributable to this transition was also recognized in the resonance Raman spectra. Emission spectroscopies showed two distinct emission bands. The lower energy band, resulting from radiative decay of the CT excited state, exhibited large anomalous Stokes shifts of ∼9000 cm-1. Much of the Stokes shift was a consequence of geometry changes between the ground and excited states. This was confirmed by variable temperature emission studies, with Stokes shifts reducing by up to 3000 cm-1 upon cooling from 293 to 80 K. Additionally, a high energy aggregation induced emission band was present for two of the dyes, resulting from the inhibition of excited state geometry reorganization and supported by solid-state emission spectra. These phenomena exemplify the importance of geometry in short range donor-acceptor dyes such as these.

7.
Adv Exp Med Biol ; 1344: 169-188, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34773232

RESUMEN

It is becoming increasingly recognized that patients with a variety of neurodegenerative diseases exhibit disordered sleep/wake patterns. While sleep impairments have typically been thought of as sequelae of underlying neurodegenerative processes in sleep-wake cycle regulating brain regions, including the brainstem, hypothalamus, and basal forebrain, emerging evidence now indicates that sleep deficits may also act as pathophysiological drivers of brain-wide disease progression. Specifically, recent work has indicated that impaired sleep can impact on neuronal activity, brain clearance mechanisms, pathological build-up of proteins, and inflammation. Altered sleep patterns may therefore be novel (potentially reversible) dynamic functional markers of proteinopathies and modifiable targets for early therapeutic intervention using non-invasive stimulation and behavioral techniques. Here we highlight research describing a potentially reciprocal interaction between impaired sleep and circadian patterns and the accumulation of pathological signs and features in Alzheimer's disease, the most prevalent neurodegenerative disease in the elderly.


Asunto(s)
Enfermedad de Alzheimer , Prosencéfalo Basal , Enfermedades Neurodegenerativas , Anciano , Péptidos beta-Amiloides/metabolismo , Humanos , Sueño
8.
Lancet Oncol ; 21(11): 1478-1488, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33128873

RESUMEN

BACKGROUND: CH5126766 (also known as VS-6766, and previously named RO5126766), a novel MEK-pan-RAF inhibitor, has shown antitumour activity across various solid tumours; however, its initial development was limited by toxicity. We aimed to investigate the safety and toxicity profile of intermittent dosing schedules of CH5126766, and the antitumour activity of this drug in patients with solid tumours and multiple myeloma harbouring RAS-RAF-MEK pathway mutations. METHODS: We did a single-centre, open-label, phase 1 dose-escalation and basket dose-expansion study at the Royal Marsden National Health Service Foundation Trust (London, UK). Patients were eligible for the study if they were aged 18 years or older, had cancers that were refractory to conventional treatment or for which no conventional therapy existed, and if they had a WHO performance status score of 0 or 1. For the dose-escalation phase, eligible patients had histologically or cytologically confirmed advanced or metastatic solid tumours. For the basket dose-expansion phase, eligible patients had advanced or metastatic solid tumours or multiple myeloma harbouring RAS-RAF-MEK pathway mutations. During the dose-escalation phase, we evaluated three intermittent oral schedules (28-day cycles) in patients with solid tumours: (1) 4·0 mg or 3·2 mg CH5126766 three times per week; (2) 4·0 mg CH5126766 twice per week; and (3) toxicity-guided dose interruption schedule, in which treatment at the recommended phase 2 dose (4·0 mg CH5126766 twice per week) was de-escalated to 3 weeks on followed by 1 week off if patients had prespecified toxic effects (grade 2 or worse diarrhoea, rash, or creatinine phosphokinase elevation). In the basket dose-expansion phase, we evaluated antitumour activity at the recommended phase 2 dose, determined from the dose-escalation phase, in biomarker-selected patients. The primary endpoints were the recommended phase 2 dose at which no more than one out of six patients had a treatment-related dose-limiting toxicity, and the safety and toxicity profile of each dosing schedule. The key secondary endpoint was investigator-assessed response rate in the dose-expansion phase. Patients who received at least one dose of the study drug were evaluable for safety and patients who received one cycle of the study drug and underwent baseline disease assessment were evaluable for response. This trial is registered with ClinicalTrials.gov, NCT02407509. FINDINGS: Between June 5, 2013, and Jan 10, 2019, 58 eligible patients were enrolled to the study: 29 patients with solid tumours were included in the dose-escalation cohort and 29 patients with solid tumours or multiple myeloma were included in the basket dose-expansion cohort (12 non-small-cell lung cancer, five gynaecological malignancy, four colorectal cancer, one melanoma, and seven multiple myeloma). Median follow-up at the time of data cutoff was 2·3 months (IQR 1·6-3·5). Dose-limiting toxicities included grade 3 bilateral retinal pigment epithelial detachment in one patient who received 4·0 mg CH5126766 three times per week, and grade 3 rash (in two patients) and grade 3 creatinine phosphokinase elevation (in one patient) in those who received 3·2 mg CH5126766 three times per week. 4·0 mg CH5126766 twice per week (on Monday and Thursday or Tuesday and Friday) was established as the recommended phase 2 dose. The most common grade 3-4 treatment-related adverse events were rash (11 [19%] patients), creatinine phosphokinase elevation (six [11%]), hypoalbuminaemia (six [11%]), and fatigue (four [7%]). Five (9%) patients had serious treatment-related adverse events. There were no treatment-related deaths. Eight (14%) of 57 patients died during the trial due to disease progression. Seven (27% [95% CI 11·6-47·8]) of 26 response-evaluable patients in the basket expansion achieved objective responses. INTERPRETATION: To our knowledge, this is the first study to show that highly intermittent schedules of a RAF-MEK inhibitor has antitumour activity across various cancers with RAF-RAS-MEK pathway mutations, and that this inhibitor is tolerable. CH5126766 used as a monotherapy and in combination regimens warrants further evaluation. FUNDING: Chugai Pharmaceutical.


Asunto(s)
Cumarinas/administración & dosificación , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/patología , Mieloma Múltiple/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/administración & dosificación , Administración Oral , Adulto , Anciano , Cumarinas/efectos adversos , Relación Dosis-Respuesta a Droga , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/clasificación , Femenino , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/genética , Mieloma Múltiple/patología , Inhibidores de Proteínas Quinasas/efectos adversos , Quinasas raf/genética , Proteínas ras/genética
9.
Eur J Nucl Med Mol Imaging ; 46(5): 1092-1101, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30547207

RESUMEN

PURPOSE: Concomitant treatment with radium-223 and paclitaxel is a potential option for cancer patients with bone metastases; however, myelosuppression risk during coadministration is unknown. This phase Ib study in cancer patients with bone metastases evaluated the safety of radium-223 and paclitaxel. METHODS: Eligible patients had solid tumor malignancies with ≥2 bone metastases and were candidates for paclitaxel. Treatment included seven paclitaxel cycles (90 mg/m2 per week intravenously per local standard of care; 3 weeks on/1 week off) plus six radium-223 cycles (55 kBq/kg intravenously; one injection every 4 weeks, starting at paclitaxel cycle 2). The primary end point was percentage of patients with grade 3/4 neutropenia or thrombocytopenia during coadministration of radium-223 and paclitaxel (cycles 2, 3) versus paclitaxel alone (cycle 1). RESULTS: Of 22 enrolled patients, 15 were treated (safety population), with 7 completing all six radium-223 cycles. Treated patients had primary cancers of breast (n = 7), prostate (n = 4), bladder (n = 1), non-small cell lung (n = 1), myxofibrosarcoma (n = 1), and neuroendocrine (n = 1). No patients discontinued treatment from toxicity of the combination. In the 13 patients who completed cycle 3, the rates of grade 3 neutropenia in cycles 2 and 3 were 31% and 8%, respectively, versus 23% in cycle 1; there were no cases of grade 4 neutropenia or grade 3/4 thrombocytopenia. Breast cancer subgroup safety results were similar to the overall safety population. CONCLUSION: Radium-223 was tolerated when combined with weekly paclitaxel, with no clinically relevant additive toxicities. This combination should be explored further in patients with bone metastases.


Asunto(s)
Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/radioterapia , Paclitaxel/efectos adversos , Paclitaxel/uso terapéutico , Radio (Elemento)/efectos adversos , Radio (Elemento)/uso terapéutico , Seguridad , Anciano , Neoplasias Óseas/secundario , Terapia Combinada/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad
10.
Neuroimage ; 171: 165-175, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29294386

RESUMEN

Whether functional hyperemia during epileptic activity is adequate to meet the heightened metabolic demand of such events is controversial. Whereas some studies have demonstrated hyperoxia during ictal onsets, other work has reported transient hypoxic episodes that are spatially dependent on local surface microvasculature. Crucially, how laminar differences in ictal evolution can affect subsequent cerebrovascular responses has not been thus far investigated, and is likely significant in view of possible laminar-dependent neurovascular mechanisms and angioarchitecture. We addressed this open question using a novel multi-modal methodology enabling concurrent measurement of cortical tissue oxygenation, blood flow and hemoglobin concentration, alongside laminar recordings of neural activity, in a urethane anesthetized rat model of recurrent seizures induced by 4-aminopyridine. We reveal there to be a close relationship between seizure epicenter depth, translaminar local field potential (LFP) synchrony and tissue oxygenation during the early stages of recurrent seizures, whereby deep layer seizures are associated with decreased cross laminar synchrony and prolonged periods of hypoxia, and middle layer seizures are accompanied by increased cross-laminar synchrony and hyperoxia. Through comparison with functional activation by somatosensory stimulation and graded hypercapnia, we show that these seizure-related cerebrovascular responses occur in the presence of conserved neural-hemodynamic and blood flow-volume coupling. Our data provide new insights into the laminar dependency of seizure-related neurovascular responses, which may reconcile inconsistent observations of seizure-related hypoxia in the literature, and highlight a potential layer-dependent vulnerability that may contribute to the harmful effects of clinical recurrent seizures. The relevance of our findings to perfusion-related functional neuroimaging techniques in epilepsy are also discussed.


Asunto(s)
Encéfalo/irrigación sanguínea , Encéfalo/fisiopatología , Hiperoxia/fisiopatología , Convulsiones/fisiopatología , Animales , Circulación Cerebrovascular/fisiología , Femenino , Hemodinámica/fisiología , Ratas
11.
Br J Cancer ; 119(8): 922-927, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30318518

RESUMEN

BACKGROUND: Greater understanding of the molecular classification of breast cancer has permitted the development of rational drug design strategies. In a phase I clinical trial setting, molecular profiling with next-generation sequencing of individual tumour samples has been employed to guide treatment. METHODS: We conducted a retrospective evaluation of clinical outcomes of patients with metastatic breast cancer (MBC) treated in phase I clinical trials at our institution to assess the benefit of molecularly matched compared to non-matched treatments. RESULTS: A total of 97 consecutive patients with MBC were enrolled onto ≥1 trial between 2009 and 2015. Fourteen patients participated in multiple trials, and a total of 113 trial encounters were reviewed in this retrospective study. Eighty-three percent of patients with molecular data available were able to participate in trials matched to molecular aberrations. Patients who were treated on matched studies had improved clinical benefit (RR: 1.80, p = 0.005), progression-free (HR: 0.52, p = 0.003) and overall survival (HR: 0.54, p < 0.001). Treatment was well tolerated with low rates of treatment discontinuation for toxicity (8% overall) that did not differ between groups. No toxicity-related deaths were observed. CONCLUSIONS: Molecular profiling for MBC patients in a phase I setting is feasible and aids therapeutic decisions with improved patient outcomes.


Asunto(s)
Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Ensayos Clínicos Fase I como Asunto/métodos , Terapia Molecular Dirigida/métodos , Adulto , Anciano , Anciano de 80 o más Años , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama/patología , Supervivencia sin Enfermedad , Inglaterra , Femenino , Humanos , Persona de Mediana Edad , Receptor ErbB-2/genética , Receptores de Estrógenos/genética , Estudios Retrospectivos , Centros de Atención Terciaria
13.
J Neurosci ; 35(11): 4641-56, 2015 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-25788681

RESUMEN

Studies that use prolonged periods of sensory stimulation report associations between regional reductions in neural activity and negative blood oxygenation level-dependent (BOLD) signaling. However, the neural generators of the negative BOLD response remain to be characterized. Here, we use single-impulse electrical stimulation of the whisker pad in the anesthetized rat to identify components of the neural response that are related to "negative" hemodynamic changes in the brain. Laminar multiunit activity and local field potential recordings of neural activity were performed concurrently with two-dimensional optical imaging spectroscopy measuring hemodynamic changes. Repeated measurements over multiple stimulation trials revealed significant variations in neural responses across session and animal datasets. Within this variation, we found robust long-latency decreases (300 and 2000 ms after stimulus presentation) in gamma-band power (30-80 Hz) in the middle-superficial cortical layers in regions surrounding the activated whisker barrel cortex. This reduction in gamma frequency activity was associated with corresponding decreases in the hemodynamic responses that drive the negative BOLD signal. These findings suggest a close relationship between BOLD responses and neural events that operate over time scales that outlast the initiating sensory stimulus, and provide important insights into the neurophysiological basis of negative neuroimaging signals.


Asunto(s)
Ritmo Gamma/fisiología , Hemodinámica/fisiología , Corteza Somatosensorial/fisiología , Animales , Estimulación Eléctrica/métodos , Femenino , Predicción , Ratas , Factores de Tiempo , Vibrisas/fisiología
14.
Gen Comp Endocrinol ; 213: 32-9, 2015 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-25575655

RESUMEN

Male courtship displays may be regulated by, and affect the production of, circulating hormones. The Energetics-Hormone Vocalization (EHV) model, for example, posits that interactions among chorusing male anuran amphibians stimulate androgen production that then mediates an increase in vocal effort. Increased vocal effort is expected to deplete energy reserves and increase glucocorticoid levels that, in turn, negatively affect androgen levels and vocalization. Androgen levels, glucocorticoid levels, and vocal effort are thus expected to increase across and within nights of chorus activity and should be positively correlated in calling males; energy reserves should decline temporally and be inversely related to glucocorticoid levels. We tested predictions of the EHV model in the green treefrog, Hyla cinerea. Consistent with the model, both testosterone and dihydrotestosterone levels increased across the breeding season in calling males. However, testosterone levels decreased and dihydrotestosterone levels did not change within nights of chorus activity, suggesting that chorusing behavior did not drive the seasonal elevation in androgens. Corticosterone (CORT) level remained relatively stable across the breeding season and decreased within nights of chorus activity, contrary to model predictions. Body condition, the proxy for energetic state, was inversely correlated with CORT level but discrepancies between model predictions and temporal patterns of CORT production arose because there was no evidence of a temporal decrease in body condition or increase in vocal effort. Moreover, androgen and CORT levels were not positively correlated with vocal effort. Additional ecological and physiological measures may be needed to support predictions of the EHV model.


Asunto(s)
Andrógenos/sangre , Corticosterona/sangre , Ranidae/fisiología , Conducta Sexual Animal/fisiología , Testosterona/sangre , Vocalización Animal/fisiología , Animales , Masculino , Radioinmunoensayo , Estaciones del Año
15.
Nat Neurosci ; 27(4): 643-655, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38424324

RESUMEN

Dipeptide repeat proteins are a major pathogenic feature of C9orf72 amyotrophic lateral sclerosis (C9ALS)/frontotemporal dementia (FTD) pathology, but their physiological impact has yet to be fully determined. Here we generated C9orf72 dipeptide repeat knock-in mouse models characterized by expression of 400 codon-optimized polyGR or polyPR repeats, and heterozygous C9orf72 reduction. (GR)400 and (PR)400 knock-in mice recapitulate key features of C9ALS/FTD, including cortical neuronal hyperexcitability, age-dependent spinal motor neuron loss and progressive motor dysfunction. Quantitative proteomics revealed an increase in extracellular matrix (ECM) proteins in (GR)400 and (PR)400 spinal cord, with the collagen COL6A1 the most increased protein. TGF-ß1 was one of the top predicted regulators of this ECM signature and polyGR expression in human induced pluripotent stem cell neurons was sufficient to induce TGF-ß1 followed by COL6A1. Knockdown of TGF-ß1 or COL6A1 orthologues in polyGR model Drosophila exacerbated neurodegeneration, while expression of TGF-ß1 or COL6A1 in induced pluripotent stem cell-derived motor neurons of patients with C9ALS/FTD protected against glutamate-induced cell death. Altogether, our findings reveal a neuroprotective and conserved ECM signature in C9ALS/FTD.


Asunto(s)
Esclerosis Amiotrófica Lateral , Demencia Frontotemporal , Células Madre Pluripotentes Inducidas , Animales , Humanos , Ratones , Demencia Frontotemporal/patología , Esclerosis Amiotrófica Lateral/metabolismo , Factor de Crecimiento Transformador beta1 , Proteína C9orf72/genética , Proteína C9orf72/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Neuronas Motoras/metabolismo , Drosophila , Matriz Extracelular/metabolismo , Dipéptidos/metabolismo , Expansión de las Repeticiones de ADN/genética
16.
Horm Behav ; 63(1): 20-4, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23160001

RESUMEN

Circulating glucocorticoids and androgens often figure prominently in mating tactic expression in vertebrates. In anuran amphibians (frogs and toads), for example, recent models predict that the depletion of energy reserves during vocalization will result in increased glucocorticoid levels; high glucocorticoids are expected to negatively affect androgen level to mediate transitions from calling to non-calling behavior. Consistent with these predictions, we show that male green treefrogs (Hyla cinerea) adopting an alternative non-calling "satellite" mating tactic were in poorer condition and had higher circulating corticosterone levels and lower androgen levels than calling males. Body condition was inversely related to corticosterone level and positively related to testosterone, but not dihydrotestosterone, level. Corticosterone level was inversely related to testosterone level but not dihydrotestosterone level. Lastly, we show that calling males that were involved in aggressive bouts had higher corticosterone levels than calling males that were not involved in aggressive bouts. Our results are thus consistent with the prediction that aggressive interactions with conspecific males contribute to high corticosterone levels in satellite males that were observed to lose aggressive contests with larger calling males.


Asunto(s)
Anuros/fisiología , Corticosterona/sangre , Conducta Sexual Animal/fisiología , Testosterona/sangre , Vocalización Animal/fisiología , Animales , Anuros/sangre , Dihidrotestosterona/sangre , Masculino
17.
Cureus ; 15(6): e40939, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37496551

RESUMEN

Clinical evidence demonstrates that patients with telomere biology disorders, such as dyskeratosis congenita, are more prone to coronary artery disease. We present the case of a 43-year-old female diagnosed with dyskeratosis congenita with critical cardiovascular disease. She underwent coronary artery bypass graft (CABG) with improvement of her cardiac function. Although this is a rare genetic disease, further studies are warranted to investigate the underlying pathophysiology of cardiovascular disease in patients with dyskeratosis congenita.

18.
Cureus ; 15(11): e49418, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38149125

RESUMEN

This unique case depicts the first published report of a physician using point-of-care ultrasound to diagnose an esophageal stent migration. Discussed in this article are the sonographic findings that clinicians should be familiar with when evaluating patients with abdominal pain or chest pain who have a history of an esophageal stent. When coupled with a high index of suspicion, ultrasound can be one of the most portable, readily available, low-cost, and minimally invasive techniques for making a rapid diagnosis of esophageal stent migration.

19.
Respir Med Case Rep ; 46: 101925, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37869609

RESUMEN

Thoracic hernias are characterized by the protrusion of the thoracic contents outside their normal anatomical confines. This case involves a left pleural effusion secondary to a spontaneous lung intercostal hernia (SLIH) in a 52-year-old male. Imaging revealed herniated pleural fluid in the intercostal space. Intra-operatively, there was herniation of the lung parenchyma into an intercostal defect. Pleural effusion secondary to a SLIH is an indication for surgical repair.

20.
Commun Biol ; 6(1): 185, 2023 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-36797344

RESUMEN

Neurovascular coupling (NVC) is a mechanism that, amongst other known and latent critical functions, ensures activated brain regions are adequately supplied with oxygen and glucose. This biological phenomenon underpins non-invasive perfusion-related neuroimaging techniques and recent reports have implicated NVC impairment in several neurodegenerative disorders. Yet, much remains unknown regarding NVC in health and disease, and only recently has there been burgeoning recognition of a close interplay with brain thermodynamics. Accordingly, we developed a novel multi-modal approach to systematically modulate cortical temperature and interrogate the spatiotemporal dynamics of sensory-evoked NVC. We show that changes in cortical temperature profoundly and intricately modulate NVC, with low temperatures associated with diminished oxygen delivery, and high temperatures inducing a distinct vascular oscillation. These observations provide novel insights into the relationship between NVC and brain thermodynamics, with important implications for brain-temperature related therapies, functional biomarkers of elevated brain temperature, and in-vivo methods to study neurovascular coupling.


Asunto(s)
Encéfalo , Acoplamiento Neurovascular , Temperatura , Acoplamiento Neurovascular/fisiología , Reconocimiento en Psicología , Oxígeno
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