Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.564
Filtrar
1.
Nucleic Acids Res ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647050

RESUMO

CpG islands near promoters are normally unmethylated despite being surrounded by densely methylated regions. Aberrant hypermethylation of these CpG islands has been associated with the development of various human diseases. Although local genetic elements have been speculated to play a role in protecting promoters from methylation, only a limited number of methylation barriers have been identified. In this study, we conducted an integrated computational and experimental investigation of colorectal cancer methylomes. Our study revealed 610 genes with disrupted methylation barriers. Genomic sequences of these barriers shared a common 41-bp sequence motif (MB-41) that displayed homology to the chicken HS4 methylation barrier. Using the CDKN2A (P16) tumor suppressor gene promoter, we validated the protective function of MB-41 and showed that loss of such protection led to aberrant hypermethylation. Our findings highlight a novel sequence signature of cis-acting methylation barriers in the human genome that safeguard promoters from silencing.

2.
EClinicalMedicine ; 68: 102383, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38545090

RESUMO

Background: SARS-CoV-2 binding to ACE2 is potentially associated with severe pneumonia due to COVID-19. The aim of the study was to test whether Mas-receptor activation by 20-hydroxyecdysone (BIO101) could restore the Renin-Angiotensin System equilibrium and limit the frequency of respiratory failure and mortality in adults hospitalized with severe COVID-19. Methods: Double-blind, randomized, placebo-controlled phase 2/3 trial. Randomization: 1:1 oral BIO101 (350 mg BID) or placebo, up to 28 days or until an endpoint was reached. Primary endpoint: mortality or respiratory failure requiring high-flow oxygen, mechanical ventilation, or extra-corporeal membrane oxygenation. Key secondary endpoint: hospital discharge following recovery (ClinicalTrials.gov Number, NCT04472728). Findings: Due to low recruitment the planned sample size of 310 was not reached and 238 patients were randomized between August 26, 2020 and March 8, 2022. In the modified ITT population (233 patients; 126 BIO101 and 107 placebo), respiratory failure or early death by day 28 was 11.4% lower in the BIO101 (13.5%) than in the placebo (24.3%) group, (p = 0.0426). At day 28, proportions of patients discharged following recovery were 80.1%, and 70.9% in the BIO101 and placebo group respectively, (adjusted difference 11.0%, 95% CI [-0.4%, 22.4%], p = 0.0586). Hazard Ratio for time to death over 90 days: 0.554 (95% CI [0.285, 1.077]), a 44.6% mortality reduction in the BIO101 group (not statistically significant). Treatment emergent adverse events of respiratory failure were more frequent in the placebo group. Interpretation: BIO101 significantly reduced the risk of death or respiratory failure supporting its use in adults hospitalized with severe respiratory symptoms due to COVID-19. Funding: Biophytis.

3.
Int J Mol Sci ; 25(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38474284

RESUMO

N-retinylidene-N-retinylethanolamine (A2E) has been associated with age-related macular degeneration (AMD) physiopathology by inducing cell death, angiogenesis and inflammation in retinal pigmented epithelial (RPE) cells. It was previously thought that the A2E effects were solely mediated via the retinoic acid receptor (RAR)-α activation. However, this conclusion was based on experiments using the RAR "specific" antagonist RO-41-5253, which was found to also be a ligand and partial agonist of the peroxisome proliferator-activated receptor (PPAR)-γ. Moreover, we previously reported that inhibiting PPAR and retinoid X receptor (RXR) transactivation with norbixin also modulated inflammation and angiogenesis in RPE cells challenged in the presence of A2E. Here, using several RAR inhibitors, we deciphered the respective roles of RAR, PPAR and RXR transactivations in an in vitro model of AMD. We showed that BMS 195614 (a selective RAR-α antagonist) displayed photoprotective properties against toxic blue light exposure in the presence of A2E. BMS 195614 also significantly reduced the AP-1 transactivation and mRNA expression of the inflammatory interleukin (IL)-6 and vascular endothelial growth factor (VEGF) induced by A2E in RPE cells in vitro, suggesting a major role of RAR in these processes. Surprisingly, however, we showed that (1) Norbixin increased the RAR transactivation and (2) AGN 193109 (a high affinity pan-RAR antagonist) and BMS 493 (a pan-RAR inverse agonist), which are photoprotective against toxic blue light exposure in the presence of A2E, also inhibited PPARs transactivation and RXR transactivation, respectively. Therefore, in our in vitro model of AMD, several commercialized RAR inhibitors appear to be non-specific, and we propose that the phototoxicity and expression of IL-6 and VEGF induced by A2E in RPE cells operates through the activation of PPAR or RXR rather than by RAR transactivation.


Assuntos
Carotenoides , Degeneração Macular , Receptores Ativados por Proliferador de Peroxissomo , Quinolinas , para-Aminobenzoatos , Anti-Inflamatórios , Agonismo Inverso de Drogas , Inflamação , Degeneração Macular/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Receptor alfa de Ácido Retinoico/metabolismo , Receptores X de Retinoides/metabolismo , Retinoides/metabolismo , Ativação Transcricional , Fator A de Crescimento do Endotélio Vascular/metabolismo
4.
Mol Cancer Ther ; 23(5): 595-605, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38530115

RESUMO

Methionine aminopeptidase type 2 (METAP2) is a ubiquitous, evolutionarily conserved metalloprotease fundamental to protein biosynthesis which catalyzes removal of the N-terminal methionine residue from nascent polypeptides. METAP2 is an attractive target for cancer therapeutics based upon its over-expression in multiple human cancers, the importance of METAP2-specific substrates whose biological activity may be altered following METAP2 inhibition, and additionally, that METAP2 was identified as the target for the anti-angiogenic natural product, fumagillin. Irreversible inhibition of METAP2 using fumagillin analogues has established the anti-angiogenic and anti-tumor characteristics of these derivatives; however, their full clinical potential has not been realized due to a combination of poor drug-like properties and dose-limiting central nervous system (CNS) toxicity. This report describes the physicochemical and pharmacological characterization of SDX-7320 (evexomostat), a polymer-drug conjugate of the novel METAP2 inhibitor (METAP2i) SDX-7539. In vitro binding, enzyme, and cell-based assays demonstrated that SDX-7539 is a potent and selective METAP2 inhibitor. In utilizing a high molecular weight, water-soluble polymer to conjugate the novel fumagillol-derived, cathepsin-released, METAP2i SDX-7539, limitations observed with prior generation, small molecule fumagillol derivatives were ameliorated including reduced CNS exposure of the METAP2i, and prolonged half-life enabling convenient administration. Multiple xenograft and syngeneic cancer models were utilized to demonstrate the anti-tumor and anti-metastatic profile of SDX-7320. Unlike polymer-drug conjugates in general, reductions in small molecule-equivalent efficacious doses following polymer conjugation were observed. SDX-7320 has completed a phase I clinical safety study in patients with late-stage cancer and is currently being evaluated in multiple phase Ib/II clinical studies in patients with advanced solid tumors.


Assuntos
Aminopeptidases , Antineoplásicos , Ensaios Antitumorais Modelo de Xenoenxerto , Humanos , Animais , Aminopeptidases/antagonistas & inibidores , Aminopeptidases/metabolismo , Camundongos , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/química , Metionil Aminopeptidases/antagonistas & inibidores , Metaloendopeptidases/antagonistas & inibidores , Metástase Neoplásica , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Cicloexanos/farmacologia , Cicloexanos/química , Feminino , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Proliferação de Células/efeitos dos fármacos
5.
Cells ; 13(4)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38391904

RESUMO

Acting as GTPase activating proteins promoting the silencing of activated G-proteins, regulators of G protein signaling (RGSs) are generally considered negative modulators of cell signaling. In the CNS, the expression of RGS4 is altered in diverse pathologies and its upregulation was reported in astrocytes exposed to an inflammatory environment. In a model of cultured cortical astrocytes, we herein investigate the influence of RGS4 on intracellular calcium signaling mediated by type 5 metabotropic glutamate receptor (mGluR5), which is known to support the bidirectional communication between neurons and glial cells. RGS4 activity was manipulated by exposure to the inhibitor CCG 63802 or by infecting the cells with lentiviruses designed to achieve the silencing or overexpression of RGS4. The pharmacological inhibition or silencing of RGS4 resulted in a decrease in the percentage of cells responding to the mGluR5 agonist DHPG and in the proportion of cells showing typical calcium oscillations. Conversely, RGS4-lentivirus infection increased the percentage of cells showing calcium oscillations. While the physiological implication of cytosolic calcium oscillations in astrocytes is still under investigation, the fine-tuning of calcium signaling likely determines the coding of diverse biological events. Indirect signaling modulators such as RGS4 inhibitors, used in combination with receptor ligands, could pave the way for new therapeutic approaches for diverse neurological disorders with improved efficacy and selectivity.


Assuntos
Proteínas RGS , Receptores de Glutamato Metabotrópico , Ratos , Animais , Receptores de Glutamato Metabotrópico/metabolismo , Cálcio/metabolismo , Astrócitos/metabolismo , Ratos Sprague-Dawley , Proteínas RGS/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Sinalização do Cálcio
6.
Leukemia ; 38(3): 570-578, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38321107

RESUMO

Myeloproliferative neoplasms (MPNs) are a group of chronic hematologic malignancies that lead to morbidity and early mortality due to thrombotic complications and progression to acute leukemia. Clinical and mutational risk factors have been demonstrated to predict outcomes in patients with MPNs and are used commonly to guide therapeutic decisions, including allogenic stem cell transplant, in myelofibrosis. Adolescents and young adults (AYA, age ≤45 years) comprise less than 10% of all MPN patients and have unique clinical and therapeutic considerations. The prevalence and clinical impact of somatic mutations implicated in myeloid disease has not been extensively examined in this population. We conducted a retrospective review of patients evaluated at eight Canadian centers for MPN patients diagnosed at ≤45 years of age. In total, 609 patients were included in the study, with median overall survival of 36.8 years. Diagnosis of prefibrotic or overt PMF is associated with the lowest OS and highest risk of AP/BP transformation. Thrombotic complications (24%), including splanchnic circulation thrombosis (9%), were frequent in the cohort. Mutations in addition to those in JAK2/MPL/CALR are uncommon in the initial disease phase in our AYA population (12%); but our data indicate they may be predictive of transformation to post-ET/PV myelofibrosis.


Assuntos
Transtornos Mieloproliferativos , Policitemia Vera , Mielofibrose Primária , Trombocitemia Essencial , Trombose , Humanos , Adulto Jovem , Adolescente , Pessoa de Meia-Idade , Mielofibrose Primária/genética , Mielofibrose Primária/terapia , Policitemia Vera/genética , Trombocitemia Essencial/genética , Canadá/epidemiologia , Transtornos Mieloproliferativos/complicações , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/terapia , Trombose/genética , Janus Quinase 2/genética , Mutação , Calreticulina/genética
7.
Neurobiol Dis ; 192: 106417, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38296112

RESUMO

Stress disorders are psychiatric disorders arising following stressful or traumatic events. They could deleteriously affect an individual's health because they often co-occur with mental illnesses. Considerable attention has been focused on neurons when considering the neurobiology of stress disorders. However, like other mental health conditions, recent studies have highlighted the importance of astrocytes in the pathophysiology of stress-related disorders. In addition to their structural and homeostatic support role, astrocytes actively serve several functions in regulating synaptic transmission and plasticity, protecting neurons from toxic compounds, and providing metabolic support for neurons. The astrocyte-neuron lactate shuttle model sets forth the importance of astrocytes in providing lactate for the metabolic supply of neurons under intense activity. Lactate also plays a role as a signaling molecule and has been recently studied regarding its antidepressant activity. This review discusses the involvement of astrocytes and brain energy metabolism in stress and further reflects on the importance of lactate as an energy supply in the brain and its emerging antidepressant role in stress-related disorders.


Assuntos
Astrócitos , Ácido Láctico , Humanos , Ácido Láctico/metabolismo , Astrócitos/metabolismo , Glucose/metabolismo , Metabolismo Energético/fisiologia , Antidepressivos
8.
Clin Epigenetics ; 16(1): 3, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172923

RESUMO

BACKGROUND: Inhibition of cyclin-dependent kinase 9 (CDK9), a novel epigenetic target in cancer, can reactivate epigenetically silenced genes in cancer by dephosphorylating the SWI/SNF chromatin remodeler BRG1. Here, we characterized the anti-tumor efficacy of MC180295, a newly developed CDK9 inhibitor. METHODS: In this study, we explored the pharmacokinetics of MC180295 in mice and rats, and tested the anti-tumor efficacy of MC180295, and its enantiomers, in multiple cancer cell lines and mouse models. We also combined CDK9 inhibition with a DNA methyltransferase (DNMT) inhibitor, decitabine, in multiple mouse models, and tested MC180295 dependence on T cells. Drug toxicity was measured by checking body weights and complete blood counts. RESULTS: MC180295 had high specificity for CDK9 and high potency against multiple neoplastic cell lines (median IC50 of 171 nM in 46 cell lines representing 6 different malignancies), with the highest potency seen in AML cell lines derived from patients with MLL translocations. MC180295 is a racemic mixture of two enantiomers, MC180379 and MC180380, with MC180380 showing higher potency in a live-cell epigenetic assay. Both MC180295 and MC180380 showed efficacy in in vivo AML and colon cancer xenograft models, and significant synergy with decitabine in both cancer models. Lastly, we found that CDK9 inhibition-mediated anti-tumoral effects were partially dependent on CD8 + T cells in vivo, indicating a significant immune component to the response. CONCLUSIONS: MC180380, an inhibitor of cyclin-dependent kinase 9 (CDK9), is an efficacious anti-cancer agent worth advancing further toward clinical use.


Assuntos
Quinase 9 Dependente de Ciclina , Leucemia Mieloide Aguda , Humanos , Camundongos , Ratos , Animais , Quinase 9 Dependente de Ciclina/genética , Quinase 9 Dependente de Ciclina/metabolismo , Decitabina/farmacologia , Metilação de DNA , Linhagem Celular Tumoral , Leucemia Mieloide Aguda/genética , Apoptose
9.
J Cachexia Sarcopenia Muscle ; 15(1): 55-66, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38064183

RESUMO

BACKGROUND: Muscle aging is associated with a consistent decrease in the ability of muscle tissue to regenerate following intrinsic muscle degradation, injury or overuse. Age-related imbalance of protein synthesis and degradation, mainly regulated by AKT/mTOR pathway, leads to progressive loss of muscle mass. Maintenance of anabolic and regenerative capacities of skeletal muscles may be regarded as a therapeutic option for sarcopenia and other muscle wasting diseases. Our previous studies have demonstrated that BIO101, a pharmaceutical grade 20-hydroxyecdysone, increases protein synthesis through the activation of MAS receptor involved in the protective arm of renin-angiotensin-aldosterone system. The purpose of the present study was to assess the anabolic and pro-differentiating properties of BIO101 on C2C12 muscle cells in vitro and to investigate its effects on adult and old mice models in vivo. METHODS: The effects of BIO101 on C2C12 differentiation were assessed using myogenic transcription factors and protein expression of major kinases of AKT/mTOR pathway by Western blot. The in vivo effects of BIO101 have been investigated in BIO101 orally-treated (50 mg/kg/day) adult mice (3 months) for 28 days. To demonstrate potential beneficial effect of BIO101 treatment in a sarcopenic mouse model, we use orally treated 22-month-old C57Bl6/J mice, for 14 weeks with vehicle or BIO101. Mice body and muscle weight were recorded. Physical performances were assessed using running capacity and muscle contractility tests. RESULTS: Anabolic properties of BIO101 were confirmed by the rapid activation of AKT/mTOR, leading to an increase of C2C12 myotubes diameters (+26%, P < 0.001). Pro-differentiating effects of BIO101 on C2C12 myoblasts were revealed by increased expression of muscle-specific differentiation transcription factors (MyoD, myogenin), resulting in increased fusion index and number of nuclei per myotube (+39% and +53%, respectively, at day 6). These effects of BIO101 were like those of angiotensin (1-7) and were abolished with the use of A779, a MAS receptor specific antagonist. Chronic BIO101 oral treatment induced AKT/mTOR activation and anabolic effects accompanied with improved physical performances in adult and old animals (maximal running distance and maximal running velocity). CONCLUSIONS: Our data suggest beneficial anabolic and pro-differentiating effects of BIO101 rendering BIO101 a potent drug candidate for treating sarcopenia and possibly other muscle wasting disorders.


Assuntos
Doenças Musculares , Sarcopenia , Camundongos , Animais , Sarcopenia/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Músculo Esquelético/patologia , Doenças Musculares/metabolismo , Atrofia Muscular/patologia , Serina-Treonina Quinases TOR/metabolismo , Mioblastos/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/farmacologia
10.
Aerosp Med Hum Perform ; 95(1): 16-24, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38158569

RESUMO

BACKGROUND: In this study, we investigated the impact of a loss of horizon due to atmospheric conditions on flight performance and workload of helicopter pilots during a low-altitude, dynamic flight task in windy conditions at sea. We also examined the potential benefits of a helmet-mounted display (HMD) for this specific task.METHODS: In a fixed-based helicopter simulator, 16 military helicopter pilots were asked to follow a maneuvering go-fast vessel in a good visual environment (GVE) and in a degraded visual environment (DVE). DVE was simulated by fog, obscuring the horizon and reducing contrast. Both visual conditions were performed once with and once without an HMD, which was simulated by projecting head-slaved symbology in the outside visuals. Objective measures included flight performance, control inputs, gaze direction, and relative positioning. Subjective measures included self-ratings on performance, situation awareness, and workload.RESULTS: The results showed that in DVE the pilots perceived higher workload and were flying closer to the go-fast vessel than in GVE. Consequently, they responded with larger control inputs to maneuvers of the vessel. The availability of an HMD hardly improved flight performance but did allow the pilots to focus their attention more outside, significantly improving their situation awareness and reducing workload. These benefits were found in DVE as well as GVE conditions.DISCUSSION: DVE negatively affects workload and flight performance of helicopter pilots in a dynamic, low-altitude following task. An HMD can help improve situation awareness and lower the workload during such a task, irrespective of the visual conditions.Ledegang WD, van der Burg E, Valk PJL, Houben MMJ, Groen EL. Helicopter pilot performance and workload in a following task in a degraded visual environment. Aerosp Med Hum Perform. 2024; 95(1):16-24.


Assuntos
Medicina Aeroespacial , Pilotos , Humanos , Carga de Trabalho , Aeronaves , Conscientização , Análise e Desempenho de Tarefas
11.
PLoS One ; 18(11): e0292674, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37910493

RESUMO

The United States continues to be impacted by decades of an opioid misuse epidemic, worsened by the COVID-19 pandemic and by the growing prevalence of highly potent synthetic opioids (HPSO) such as fentanyl. In instances of a toxicity event, first-response administration of reversal medications such as naloxone can be insufficient to fully counteract the effects of HPSO, particularly when there is co-occurring substance use. In an effort to characterize and study this multi-faceted problem, the Camden Opioid Research Initiative (CORI) has been formed. The CORI study has collected and analyzed post-mortem toxicology data from 42 cases of decedents who expired from opioid-related toxicity in the South New Jersey region to characterize substance use profiles. Co-occurring substance use, whether by intent or through possible contamination of the illicit opioid supply, is pervasive among deaths due to opioid toxicity, and evidence of medication-assisted treatment is scarce. Nearly all (98%) of the toxicology cases show the presence of the HPSO, fentanyl, and very few (7%) results detected evidence of medication-assisted treatment for opioid use disorder, such as buprenorphine or methadone, at the time of death. The opioid toxicity reversal drug, naloxone, was detected in 19% of cases, but 100% of cases expressed one or more stimulants, and sedatives including xylazine were detected in 48% of cases. These results showing complex substance use profiles indicate that efforts at mitigating the opioid misuse epidemic must address the complications presented by co-occurring stimulant and other substance use, and reduce barriers to and stigmas of seeking effective medication-assisted treatments.


Assuntos
Overdose de Drogas , Transtornos Relacionados ao Uso de Opioides , Humanos , Estados Unidos , Analgésicos Opioides/efeitos adversos , Pandemias , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Fentanila/efeitos adversos , Naloxona/uso terapêutico , Overdose de Drogas/epidemiologia
12.
Proc Natl Acad Sci U S A ; 120(49): e2203241120, 2023 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-38015839

RESUMO

The Lysinibacillus sphaericus proteins Tpp49Aa1 and Cry48Aa1 can together act as a toxin toward the mosquito Culex quinquefasciatus and have potential use in biocontrol. Given that proteins with sequence homology to the individual proteins can have activity alone against other insect species, the structure of Tpp49Aa1 was solved in order to understand this protein more fully and inform the design of improved biopesticides. Tpp49Aa1 is naturally expressed as a crystalline inclusion within the host bacterium, and MHz serial femtosecond crystallography using the novel nanofocus option at an X-ray free electron laser allowed rapid and high-quality data collection to determine the structure of Tpp49Aa1 at 1.62 Å resolution. This revealed the packing of Tpp49Aa1 within these natural nanocrystals as a homodimer with a large intermolecular interface. Complementary experiments conducted at varied pH also enabled investigation of the early structural events leading up to the dissolution of natural Tpp49Aa1 crystals-a crucial step in its mechanism of action. To better understand the cooperation between the two proteins, assays were performed on a range of different mosquito cell lines using both individual proteins and mixtures of the two. Finally, bioassays demonstrated Tpp49Aa1/Cry48Aa1 susceptibility of Anopheles stephensi, Aedes albopictus, and Culex tarsalis larvae-substantially increasing the potential use of this binary toxin in mosquito control.


Assuntos
Bacillaceae , Bacillus , Culex , Praguicidas , Animais , Bacillaceae/química , Bacillaceae/metabolismo , Controle de Mosquitos , Larva/metabolismo
13.
Nat Commun ; 14(1): 7625, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993450

RESUMO

Carbon sequestration in grasslands has been proposed as an important means to offset greenhouse gas emissions from ruminant systems. To understand the potential and limitations of this strategy, we need to acknowledge that soil carbon sequestration is a time-limited benefit, and there are intrinsic differences between short- and long-lived greenhouse gases. Here, our analysis shows that one tonne of carbon sequestrated can offset radiative forcing of a continuous emission of 0.99 kg methane or 0.1 kg nitrous oxide per year over 100 years. About 135 gigatonnes of carbon is required to offset the continuous methane and nitrous oxide emissions from ruminant sector worldwide, nearly twice the current global carbon stock in managed grasslands. For various regions, grassland carbon stocks would need to increase by approximately 25% - 2,000%, indicating that solely relying on carbon sequestration in grasslands to offset warming effect of emissions from current ruminant systems is not feasible.

14.
Adv Sci (Weinh) ; 10(31): e2300473, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37661572

RESUMO

Recent advances in light-responsive materials enabled the development of devices that can wirelessly activate tissue with light. Here it is shown that solution-processed organic heterojunctions can stimulate the activity of primary neurons at low intensities of light via photochemical reactions. The p-type semiconducting polymer PDCBT and the n-type semiconducting small molecule ITIC (a non-fullerene acceptor) are coated on glass supports, forming a p-n junction with high photosensitivity. Patch clamp measurements show that low-intensity white light is converted into a cue that triggers action potentials in primary cortical neurons. The study shows that neat organic semiconducting p-n bilayers can exchange photogenerated charges with oxygen and other chemical compounds in cell culture conditions. Through several controlled experimental conditions, photo-capacitive, photo-thermal, and direct hydrogen peroxide effects on neural function are excluded, with photochemical delivery being the possible mechanism. The profound advantages of low-intensity photo-chemical intervention with neuron electrophysiology pave the way for developing wireless light-based therapy based on emerging organic semiconductors.


Assuntos
Neurônios , Semicondutores , Estimulação Química , Técnicas de Cultura de Células , Polímeros/química
15.
Proc Natl Acad Sci U S A ; 120(40): e2306492120, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37748068

RESUMO

The ~2,000-km-long Central Range of New Guinea is a hotspot of modern carbon sequestration due to the chemical weathering of igneous rocks with steep topography in the warm wet tropics. These high mountains formed in a collision between the Australian plate and ophiolite-bearing volcanic arc terranes, but poor resolution of the uplift and exhumation history has precluded assessments of the impact on global climate change. Here, we develop a palinspastic reconstruction of the Central Range orogen with existing surface geological constraints and seismic data to generate time-temperature paths and estimate volumes of eroded material. New (U-Th)/He thermochronology data reveal rapid uplift and regional denudation between 10 and 6 Mya. Erosion fluxes from the palinspastic reconstruction, calibrated for time with the thermochronological data, were used as input to a coupled global climate and weathering model. This model estimates 0.6 to 1.2 °C of cooling associated with the Late Miocene rise of New Guinea due to increased silicate weathering alone, and this CO2 sink continues to the present. Our data and modeling experiments support the hypothesis that tropical arc-continent collision and the rise of New Guinea contributed to Neogene cooling due to increased silicate weathering.

16.
J Gerontol Nurs ; 49(10): 36-43, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37768587

RESUMO

New housing models have emerged in Europe, Australia, the United States, and Canada. Intended for individuals with neurocognitive disorders, these models are characterized by a philosophy centered on the person, self-determination, liberty of choice, flexibility of care, acceptance of risk, and autonomy. Work and care are organized according to the pace and preferences of residents. The current multiple case study highlights the main sources of job satisfaction for caregivers and other employees in four innovative residential settings. Five themes are addressed as perceived by 58 employees: Work Motivation, Work Organization, Collaboration and Decision-Making Latitude, Quality of Work Life, and Continuing Education. These data will help inform clinical staff, policymakers, and the scientific community about clinical and organizational practices that contribute to job satisfaction in innovative residential settings. [Journal of Gerontological Nursing, 49(10), 36-43.].


Assuntos
Cuidadores , Satisfação no Emprego , Humanos , Assistência de Longa Duração , Austrália , Cognição
17.
MAbs ; 15(1): 2254676, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37698877

RESUMO

Prolactin (PRL) has recently been demonstrated to elicit female-selective nociceptor sensitization and increase pain-like behaviors in female animals. Here we report the discovery and characterization of first-in-class, humanized PRL neutralizing monoclonal antibodies (PRL mAbs). We obtained two potent and selective PRL mAbs, PL 200,031 and PL 200,039. PL 200,031 was engineered as human IgG1 whereas PL 200,039 was reformatted as human IgG4. Both mAbs have sub-nanomolar affinity for human PRL (hPRL) and produce concentration-dependent and complete inhibition of hPRL signaling at the hPRL receptor (hPRLR). These two PRL mAbs are selective for hPRL as they do not inhibit other hPRLR agonists such as human growth hormone or placental lactogen. They also cross-react with non-human primate PRL but not with rodent PRL. Further, both mAbs show long clearance half-lives after intravenous administration in FcRn-humanized mice. Consistent with their isotypes, these mAbs only differ in binding affinities to Fcγ receptors, as expected by design. Finally, PL 200,019, the murine parental mAb of PL 200,031 and PL 200,039, fully blocked stress-induced and PRL-dependent pain behaviors in female PRL-humanized mice, thereby providing in vivo preclinical proof-of-efficacy for PRL mAbs in mechanisms relevant to pain in females.


Assuntos
Prolactina , Receptores da Prolactina , Feminino , Camundongos , Animais , Gravidez , Prolactina/metabolismo , Prolactina/farmacologia , Receptores da Prolactina/metabolismo , Anticorpos Monoclonais , Placenta/metabolismo , Ligação Proteica
18.
Diabetes ; 72(11): 1682-1691, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37586079

RESUMO

We examined whether defects in glomerular size selectivity in type 2 diabetes are associated with progressive kidney disease. Glomerular filtration rate (GFR) and fractional clearances of dextrans of graded sizes were measured in 185 American Indians. The permselectivity model that best fit the dextran sieving data represented the glomerular capillary as being perforated by small restrictive pores and a parallel population of larger nonrestrictive pores characterized by ω0, the fraction of total filtrate volume passing through this shunt. The hazard ratio (HR) for kidney failure was expressed per 1-SD increase of ω0 by Cox regression after adjusting for age, sex, mean arterial pressure, HbA1c, GFR, and the urine albumin-to-creatinine ratio (ACR). Baseline mean ± SD age was 43 ± 10 years, HbA1c 8.9 ± 2.5%, GFR 147 ± 46 mL/min, and median (interquartile range) ACR 41 (11-230) mg/g. During a median follow-up of 17.7 years, 67 participants developed kidney failure. After adjustment, each 1-SD increment in ω0 was associated with a higher risk of kidney failure (HR 1.55 [95% CI 1.17, 2.05]). Enhanced transglomerular passage of test macromolecules was associated with progression to kidney failure, independent of albuminuria and GFR, suggesting that mechanisms associated with impaired glomerular permselectivity are important determinants of progressive kidney disease.


Assuntos
Diabetes Mellitus Tipo 2 , Nefropatias , Insuficiência Renal , Humanos , Adulto , Pessoa de Meia-Idade , Diabetes Mellitus Tipo 2/complicações , Hemoglobinas Glicadas , Glomérulos Renais , Albuminúria , Taxa de Filtração Glomerular , Insuficiência Renal/etiologia
19.
Blood Adv ; 7(17): 5027-5037, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37276510

RESUMO

This phase 3 study evaluated the efficacy and safety of the new hypomethylating agent guadecitabine (n = 408) vs a preselected treatment choice (TC; n = 407) of azacitidine, decitabine, or low-dose cytarabine in patients with acute myeloid leukemia unfit to receive intensive induction chemotherapy. Half of the patients (50%) had poor Eastern Cooperative Oncology Group Performance Status (2-3). The coprimary end points were complete remission (19% and 17% of patients for guadecitabine and TC, respectively [stratified P = .48]) and overall survival (median survival 7.1 and 8.5 months for guadecitabine and TC, respectively [hazard ratio, 0.97; 95% confidence interval, 0.83-1.14; stratified log-rank P = .73]). One- and 2-year survival estimates were 37% and 18% for guadecitabine and 36% and 14% for TC, respectively. A large proportion of patients (42%) received <4 cycles of treatment in both the arms. In a post hoc analysis of patients who received ≥4 treatment cycles, guadecitabine was associated with longer median survival vs TC (15.6 vs 13.0 months [hazard ratio, 0.78; 95% confidence interval, 0.64-0.96; log-rank P = .02]). There was no significant difference in the proportion of patients with grade ≥3 adverse events (AEs) between guadecitabine (92%) and TC (88%); however, grade ≥3 AEs of febrile neutropenia, neutropenia, and pneumonia were higher with guadecitabine. In conclusion, no significant difference was observed in the efficacy of guadecitabine and TC in the overall population. This trial was registered at www.clinicaltrials.gov as #NCT02348489.


Assuntos
Azacitidina , Leucemia Mieloide Aguda , Humanos , Resultado do Tratamento , Azacitidina/efeitos adversos , Citarabina/efeitos adversos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/tratamento farmacológico
20.
Curr Oncol ; 30(4): 4033-4040, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-37185418

RESUMO

New therapies in a publicly funded healthcare system are first appraised by health technology assessment agencies that provide funding recommendations to the payers. Treatment with Chimeric Antigen Receptor-T cell (CAR-T) therapy is revolutionizing the management of patients with relapsed/refractory aggressive B-cell lymphoma by providing an effective alternative to the standard of care. Yet, the implementation of CAR-T treatment has a substantial impact on the healthcare system due to its high cost, complex manufacturing process, and requirement for highly specialized services and expertise. CAR-T Cells, as a "living drug", are fundamentally different from usual medications, and their approvals and funding recommendations pose unique challenges to the health technology agency. In this paper, we explore the specific challenges that face the health technology agencies in reviewing reimbursement recommendations for CAR-T therapy. We take a Canadian perspective and use CAR-T treatment of relapse/refractory aggressive B-cell lymphoma as an example.


Assuntos
Linfoma de Células B , Receptores de Antígenos Quiméricos , Humanos , Receptores de Antígenos Quiméricos/uso terapêutico , Recidiva Local de Neoplasia , Canadá , Linfoma de Células B/terapia , Linfócitos T
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...