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1.
Nat Immunol ; 22(1): 53-66, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33230330

RESUMO

Regenerative stem cell-like memory (TSCM) CD8+ T cells persist longer and produce stronger effector functions. We found that MEK1/2 inhibition (MEKi) induces TSCM that have naive phenotype with self-renewability, enhanced multipotency and proliferative capacity. This is achieved by delaying cell division and enhancing mitochondrial biogenesis and fatty acid oxidation, without affecting T cell receptor-mediated activation. DNA methylation profiling revealed that MEKi-induced TSCM cells exhibited plasticity and loci-specific profiles similar to bona fide TSCM isolated from healthy donors, with intermediate characteristics compared to naive and central memory T cells. Ex vivo, antigenic rechallenge of MEKi-treated CD8+ T cells showed stronger recall responses. This strategy generated T cells with higher efficacy for adoptive cell therapy. Moreover, MEKi treatment of tumor-bearing mice also showed strong immune-mediated antitumor effects. In conclusion, we show that MEKi leads to CD8+ T cell reprogramming into TSCM that acts as a reservoir for effector T cells with potent therapeutic characteristics.


Assuntos
Antineoplásicos/farmacologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Memória Imunológica/efeitos dos fármacos , Imunoterapia Adotiva , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Neoplasias/terapia , Células-Tronco/citologia , Animais , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Ciclo Celular/efeitos dos fármacos , Humanos , Memória Imunológica/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Receptores de Antígenos de Linfócitos T/fisiologia , Microambiente Tumoral
2.
Curr Opin Neurol ; 37(1): 83-87, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38038627

RESUMO

PURPOSE OF REVIEW: Since October 2022, substantial new information has been published on age-related effects on the vestibular system. Since much of this evidence relates to the risk of dementia, the purpose of this review will be to provide an overview of this new information and critically evaluate it. RECENT FINDINGS: This review will address studies published since October 2022 regarding age-related effects on the vestibular system and their relationship to cognition and dementia. There has been a particular increase in the last year in the number of studies relating aging of the vestibular system to Alzheimer's disease (AD), further supporting the view that vestibular dysfunction is associated with an increased risk of dementia. SUMMARY: The conclusion of these recent studies is that, consistent with previous studies, vestibular function declines with age, and that this age-related decline is associated with cognitive impairment and an increased risk of dementia. Efforts are being made to consider these implications for cognition in the treatment of vestibular disorders.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Vestíbulo do Labirinto , Humanos , Envelhecimento , Disfunção Cognitiva/psicologia , Cognição
3.
Proc Biol Sci ; 291(2016): 20232361, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38351802

RESUMO

Reports of fading vole and lemming population cycles and persisting low populations in some parts of the Arctic have raised concerns about the spread of these fundamental changes to tundra food web dynamics. By compiling 24 unique time series of lemming population fluctuations across the circumpolar region, we show that virtually all populations displayed alternating periods of cyclic/non-cyclic fluctuations over the past four decades. Cyclic patterns were detected 55% of the time (n = 649 years pooled across sites) with a median periodicity of 3.7 years, and non-cyclic periods were not more frequent in recent years. Overall, there was an indication for a negative effect of warm spells occurring during the snow onset period of the preceding year on lemming abundance. However, winter duration or early winter climatic conditions did not differ on average between cyclic and non-cyclic periods. Analysis of the time series shows that there is presently no Arctic-wide collapse of lemming cycles, even though cycles have been sporadic at most sites during the last decades. Although non-stationary dynamics appears a common feature of lemming populations also in the past, continued warming in early winter may decrease the frequency of periodic irruptions with negative consequences for tundra ecosystems.


Assuntos
Arvicolinae , Ecossistema , Animais , Dinâmica Populacional , Estações do Ano , Cadeia Alimentar , Regiões Árticas
4.
Artigo em Inglês | MEDLINE | ID: mdl-38986836

RESUMO

OBJECTIVE: Patellofemoral osteoarthritis (OA) may be more common in females than males. Reasons for this are not fully understood, but sex differences in patellar morphology may help explain this phenomenon. We quantified differences in patellar morphology between males and females in healthy and patellofemoral OA populations. DESIGN: A total of 97 (50F, 47M) healthy and 67 (40F, 27M) OA knees were scanned via computed tomography. OA individuals were on a waitlist for total knee replacement. Patella 3D models were segmented and 2D measurements were recorded: patellar width and height, lateral and medial facet width, and surface area. Medial and lateral facet surface topography was mapped using 81 points to describe 3D articular surface shape. Sex and group differences were assessed using Procrustes analysis of variance (ANOVA). Data were ordinated using Principal Component Analysis. RESULTS: Differences in patellar 2D measurements between healthy and OA individuals were smaller than were differences between males and females from healthy and OA groups. Sex and healthy/OA differences were most pronounced for medial facet shape, which featured a posteriorly-curving facet and taller, narrower facet shape in males compared to females. Lateral facet shape variance was higher in OA cohorts compared to healthy groups. CONCLUSIONS: Medial and lateral facet shapes showed different patterning of variation by sex and healthy/OA status. Lateral facet shape may be of interest in future models of OA risk in the patellofemoral joint, here showing increased magnitudes of variance associated with increased severity of disease (patellofemoral Kellgren and Lawrence score).

5.
Glob Chang Biol ; 30(5): e17335, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38771086

RESUMO

Global climate change has altered the timing of seasonal events (i.e., phenology) for a diverse range of biota. Within and among species, however, the degree to which alterations in phenology match climate variability differ substantially. To better understand factors driving these differences, we evaluated variation in timing of nesting of eight Arctic-breeding shorebird species at 18 sites over a 23-year period. We used the Normalized Difference Vegetation Index as a proxy to determine the start of spring (SOS) growing season and quantified relationships between SOS and nest initiation dates as a measure of phenological responsiveness. Among species, we tested four life history traits (migration distance, seasonal timing of breeding, female body mass, expected female reproductive effort) as species-level predictors of responsiveness. For one species (Semipalmated Sandpiper), we also evaluated whether responsiveness varied across sites. Although no species in our study completely tracked annual variation in SOS, phenological responses were strongest for Western Sandpipers, Pectoral Sandpipers, and Red Phalaropes. Migration distance was the strongest additional predictor of responsiveness, with longer-distance migrant species generally tracking variation in SOS more closely than species that migrate shorter distances. Semipalmated Sandpipers are a widely distributed species, but adjustments in timing of nesting relative to variability in SOS did not vary across sites, suggesting that different breeding populations of this species were equally responsive to climate cues despite differing migration strategies. Our results unexpectedly show that long-distance migrants are more sensitive to local environmental conditions, which may help them to adapt to ongoing changes in climate.


Assuntos
Migração Animal , Mudança Climática , Comportamento de Nidação , Estações do Ano , Animais , Regiões Árticas , Migração Animal/fisiologia , Feminino , Charadriiformes/fisiologia , Reprodução
6.
Glob Chang Biol ; 30(6): e17356, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38853470

RESUMO

Seasonally abundant arthropods are a crucial food source for many migratory birds that breed in the Arctic. In cold environments, the growth and emergence of arthropods are particularly tied to temperature. Thus, the phenology of arthropods is anticipated to undergo a rapid change in response to a warming climate, potentially leading to a trophic mismatch between migratory insectivorous birds and their prey. Using data from 19 sites spanning a wide temperature gradient from the Subarctic to the High Arctic, we investigated the effects of temperature on the phenology and biomass of arthropods available to shorebirds during their short breeding season at high latitudes. We hypothesized that prolonged exposure to warmer summer temperatures would generate earlier peaks in arthropod biomass, as well as higher peak and seasonal biomass. Across the temperature gradient encompassed by our study sites (>10°C in average summer temperatures), we found a 3-day shift in average peak date for every increment of 80 cumulative thawing degree-days. Interestingly, we found a linear relationship between temperature and arthropod biomass only below temperature thresholds. Higher temperatures were associated with higher peak and seasonal biomass below 106 and 177 cumulative thawing degree-days, respectively, between June 5 and July 15. Beyond these thresholds, no relationship was observed between temperature and arthropod biomass. Our results suggest that prolonged exposure to elevated temperatures can positively influence prey availability for some arctic birds. This positive effect could, in part, stem from changes in arthropod assemblages and may reduce the risk of trophic mismatch.


Assuntos
Artrópodes , Biomassa , Estações do Ano , Temperatura , Animais , Regiões Árticas , Artrópodes/fisiologia , Mudança Climática , Cadeia Alimentar , Charadriiformes/fisiologia , Migração Animal
7.
Chem Senses ; 492024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38591722

RESUMO

Astringency is an important mouthfeel attribute that influences the sensory experiences of many food and beverage products. While salivary lubricity loss and increased oral friction were previously believed to be the only astringency mechanisms, recent research has demonstrated that nontactile oral receptors can trigger astringency by responding to astringents without mechanical stimulation. Various human factors have also been identified that affect individual responses to astringents. This article presents a critical review of the key research milestones contributing to the current understanding of astringency mechanisms and the instrumental approaches used to quantify perceived astringency intensity. Although various chemical assays or physical measures mimic in-mouth processes involved in astringent mouthfeel, this review highlights how one chemical or physical approach can only provide a single measure of astringency determined by a specific mechanism. Subsequently, using a single measurement to predict astringency perception is overly idealistic. Astringency has not been quantified beyond the loss of saliva lubrication; therefore, nontactile receptor-based responses must also be explored. An important question remains about whether astringency is a single perception or involves distinct sub-qualities such as pucker, drying, and roughness. Although these sub-quality lexicons have been frequently cited, most studies currently view astringency as a single perception rather than dividing it into sub-qualities and investigating the potentially independent mechanisms of each. Addressing these knowledge gaps should be an important priority for future research.


Assuntos
Lubrificação , Saliva , Saliva/química , Saliva/metabolismo , Humanos , Adstringentes/farmacologia , Paladar/fisiologia
8.
Conserv Biol ; 38(1): e14160, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37551779

RESUMO

The establishment of protected areas is a cornerstone of conservation, but permanent protection could be inefficient or even impossible in some situations. We synthesized the literature on temporarily conserved areas (TCAs) across Canada, the United States, and Mexico. We used a comprehensive search string to retrieve peer-reviewed articles published from 2000 to 2021 from the Web of Science. We identified 27 relevant peer-reviewed articles that examined the potential benefits of TCAs in the study area, indicating TCA is a relatively understudied area of research in the peer-reviewed literature. The TCA studies were highly clustered; 77% of studies focused on protecting a single life stage of migratory species and 61% of studies related to temporary conservation of breeding or staging habitats for migratory birds. Ninety-three percent of studies focused on preventing human-driven threats, mainly on public lands of coastal areas, the Great Plains, and the Mississippi Valley in the central United States. Short-term and experimental studies were the dominant study types. TCAs have the potential to complement permanently protected areas and provide protection when permanent protection is difficult. Some included studies examined their conservation value, but the ecological, social, and economic outcomes of TCAs are unclear. More TCA research is needed to determine the role they could play in conservation worldwide. Embracing the concept of TCAs as conservation tool could lead to more comprehensive and consistent reporting of the outcomes of temporary area-based conservation measures. However, a global review and analysis of effectiveness of TCAs will be required if they are to play a formal role in meeting international targets for biodiversity conservation.


Revisión de áreas terrestres conservadas temporalmente en Canadá, Estados Unidos y México Resumen La creación de áreas protegidas es una piedra angular de la conservación, aunque en algunos casos la protección permanente podría ser ineficiente o incluso imposible. Condensamos la literatura sobre las áreas de conservación temporal (ACT) en Canadá, Estados Unidos y México. Usamos una cadena completa de búsqueda para obtener artículos revisados por pares publicados del 2000 al 2021 en Web of Science. Identificamos 27 artículos relevantes que analizaban el potencial de las ACT en el área de estudio, lo que indica que las ACT es un área poco estudiada en la literatura revisada por pares. Los estudios sobre ACT estaban muy agrupados: el 77% se enfocaban en la protección de un solo estadio de vida de las especies migratorias y el 61% se relacionaban con la conservación temporal de los hábitats de reproducción o de descanso de las aves migratorias. El 93% de los estudios se enfocó en la prevención de amenazas causadas por humanos, principalmente en los terrenos públicos de las áreas costeras, las Grandes Llanuras y el valle del Mississippi en el centro de los Estados Unidos. Los estudios experimentales y a corto plazo fueron el tipo de estudio dominante. Las áreas de conservación temporal tienen el potencial para complementar las áreas de protección permanente y proporcionar protección cuando es complicado proporcionarla permanentemente. Algunos de los estudios incluidos analizaron el valor para la conservación de las ACT, pero aún no están claros sus resultados ecológicos, sociales y económicos. Se necesita más investigación sobre las ACT para determinar el papel que podrían tener en la conservación mundial. Si se acepta el concepto de ACT como una herramienta de conservación, se podrían reportar los resultados de las medidas de conservación basadas en las ACT de forma más completa y consistente. Sin embargo, se requerirá una revisión y análisis global de la eficiencia de las ACT si se espera que tengan un papel formal en el cumplimiento de los objetivos internacionales de la conservación de la biodiversidad.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Estados Unidos , Humanos , México , Biodiversidade , Canadá
9.
Environ Health ; 23(1): 40, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622704

RESUMO

BACKGROUND: Western Montana, USA, experiences complex air pollution patterns with predominant exposure sources from summer wildfire smoke and winter wood smoke. In addition, climate change related temperatures events are becoming more extreme and expected to contribute to increases in hospital admissions for a range of health outcomes. Evaluating while accounting for these exposures (air pollution and temperature) that often occur simultaneously and may act synergistically on health is becoming more important. METHODS: We explored short-term exposure to air pollution on children's respiratory health outcomes and how extreme temperature or seasonal period modify the risk of air pollution-associated healthcare events. The main outcome measure included individual-based address located respiratory-related healthcare visits for three categories: asthma, lower respiratory tract infections (LRTI), and upper respiratory tract infections (URTI) across western Montana for ages 0-17 from 2017-2020. We used a time-stratified, case-crossover analysis with distributed lag models to identify sensitive exposure windows of fine particulate matter (PM2.5) lagged from 0 (same-day) to 14 prior-days modified by temperature or season. RESULTS: For asthma, increases of 1 µg/m3 in PM2.5 exposure 7-13 days prior a healthcare visit date was associated with increased odds that were magnified during median to colder temperatures and winter periods. For LRTIs, 1 µg/m3 increases during 12 days of cumulative PM2.5 with peak exposure periods between 6-12 days before healthcare visit date was associated with elevated LRTI events, also heightened in median to colder temperatures but no seasonal effect was observed. For URTIs, 1 unit increases during 13 days of cumulative PM2.5 with peak exposure periods between 4-10 days prior event date was associated with greater risk for URTIs visits that were intensified during median to hotter temperatures and spring to summer periods. CONCLUSIONS: Delayed, short-term exposure increases of PM2.5 were associated with elevated odds of all three pediatric respiratory healthcare visit categories in a sparsely population area of the inter-Rocky Mountains, USA. PM2.5 in colder temperatures tended to increase instances of asthma and LRTIs, while PM2.5 during hotter periods increased URTIs.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Asma , Infecções Respiratórias , Criança , Humanos , Estados Unidos/epidemiologia , Material Particulado/efeitos adversos , Material Particulado/análise , Temperatura , Estações do Ano , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Fumaça/efeitos adversos , Asma/epidemiologia , Montana/epidemiologia , Exposição Ambiental/análise
10.
Artigo em Inglês | MEDLINE | ID: mdl-39115546

RESUMO

BACKGROUND: Many factors, including some related to the patient, implant selection, and the surgeon's skill and expertise, likely contribute to the risk of THA revision. However, surgeon factors have not been extensively analyzed in national joint replacement registries, and there is limited insight into their potential as a confounding variable for revision outcomes; for example, if surgeons with higher revision rates choose more successful prostheses, would this alone reduce their revision rate? QUESTIONS/PURPOSES: This study used Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) data for patients receiving primary THA for a diagnosis of osteoarthritis to answer the following questions: (1) Will the difference in revision rates among surgeons change or disappear when only procedures performed with the best prostheses or prostheses that have been identified as having higher revision rates are considered? (2) Is the benefit associated with using the best-performing prostheses different among surgeons with different revision rates? (3) Do the reasons for revision differ between surgeons with higher rates of revision compared with surgeons with lower rates of revision? METHODS: All primary THA procedures performed and recorded in the AOANJRR for osteoarthritis from September 1, 1999, to December 31, 2022, were considered for inclusion. Each THA prosthesis used was categorized per the AOANJRR as superior-performing, middle-performing, or identified as having a higher rate of revision by the AOANJRR benchmarking process. Surgeons who had performed at least 50 procedures and had a recorded 2-year cumulative percent revision (CPR) were included. After applying these restrictions, the study consisted of 302,066 procedures performed by 476 known surgeons. For the primary outcome measure of all-cause revision, we examined the variation in all-cause revision rates across individual surgeons when different classes of devices were used to assess whether differences between surgeons persisted when accounting for prosthesis selection. For the purposes of descriptively comparing reasons for revision between surgeons with higher-than-average or lower-than-average risk of revision, surgeons were classified into quartiles and outcomes compared when these surgeons used the same class of prosthesis. RESULTS: The difference in rates of revision among surgeons remained even after accounting for the effects of the prosthesis used. For any given surgeon, identified prostheses were associated with higher revision rates compared with both superior-performing prostheses (HR 1.73 [95% CI 1.57 to 1.92]; p < 0.01) and medium-performing prostheses (HR 1.31 [95% CI 1.20 to 1.43]; p < 0.01). All surgeons demonstrated a lower revision rate when using a superior-performing prosthesis, but the difference was greatest for surgeons with the highest rates of revision. Surgeons with the lowest rates of revision had a 19-year CPR of 3.9% (95% CI 3.0% to 5.0%) when using a superior-performing prosthesis compared with 5.4% (95% CI 4.0% to 7.3%) for procedures in which an identified prosthesis was used. Surgeons with the highest rates of revision had a 19-year CPR of 10.9% (95% CI 8.6% to 13.8%) when using a superior-performing prosthesis, and this increased to 20.4% (95% CI 18.0% to 23.1%) for procedures in which an identified prosthesis was used. The reasons for revision differ between surgeons, with causes of revision likely preventable and not related to the prosthesis choice being apparent for surgeons with high revision rates. CONCLUSION: The choice of implant and the surgeon performing the index procedure both affected the risk of revision as well as the reasons for revision. Surgeons could improve the survivorship of the arthroplasties they perform by choosing implants identified by registries as having lower revision rates. Acceptance of the fact that surgeons have different revision rates is needed, and detailed analysis is required to explain why surgeons with high revision rates have increased rates of likely preventable revisions, and outside of prosthesis choice, how revision rates can be lowered. The influence of training, fellowship completion, ongoing education, patient selection, indications for surgery, and factors underlying prosthesis decision-making should be assessed. The surgeon performing THA is an important confounder that should be considered in future registry analyses. LEVEL OF EVIDENCE: Level III, therapeutic study.

11.
J Arthroplasty ; 39(2): 343-349.e1, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37572724

RESUMO

BACKGROUND: A proportion of total knee arthroplasty (TKA) patients are dissatisfied postoperatively, particularly with their ability to perform higher-demand activities including deep-kneeling and step-up where kinematic parameters are more demanding. The purpose of this study was to examine the relationship between knee kinematics of step-up and deep-kneeling and patient-reported outcome measures following TKA. METHODS: Sixty-four patients were included at minimum 1-year follow-up. Participants performed a step-up and deep-kneeling task which was imaged via single-plane fluoroscopy. 3-dimensional prosthesis computer-aided design models were registered to the fluoroscopy, yielding in-vivo kinematic data. Associations between kinematics and patient-reported outcome measures, including Oxford Knee Score, American Knee Society Score, surgical satisfaction, and pain were assessed using log-transformed step-wise linear regressions. RESULTS: A higher total Oxford Knee Score was associated with more external rotation and more adduction at maximal flexion during kneeling and more external rotation and minimum flexion during step-up. Improved American Knee Society Score was associated with increased internal-external rotation during step-up. Improved surgical satisfaction was associated with greater maximum flexion and more external rotation at maximal flexion during deep-kneeling and more femoral internal rotation at terminal extension during step-up. An improved pain score was associated with greater maximum flexion and more femoral external rotation during deep-kneeling, as well as greater internal femoral rotation during step-up. CONCLUSION: The ability to move through full flexion/extension range and end-of-range rotation is important kinematic parameters that influence patient-reported outcome measures. Implant designs and postoperative rehabilitation should continue to focus on achieving these kinematic targets for enhanced outcomes after TKA.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Osteoartrite do Joelho , Humanos , Artroplastia do Joelho/métodos , Fenômenos Biomecânicos , Osteoartrite do Joelho/cirurgia , Desenho de Prótese , Articulação do Joelho/cirurgia , Amplitude de Movimento Articular , Dor/cirurgia
12.
Semin Cancer Biol ; 85: 185-195, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-34628029

RESUMO

Hypoxia is arguably the first recognized cancer microenvironment hallmark and affects virtually all cellular populations present in tumors. During the past decades the complex adaptive cellular responses to oxygen deprivation have been largely elucidated, raising hope for new anti cancer agents. Despite undeniable preclinical progress, therapeutic targeting of tumor hypoxia is yet to transition from bench to bedside. This review focuses on new pharmacological agents that exploit tumor hypoxia or interfere with hypoxia signaling and discusses strategies to maximize their therapeutic impact.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos , Neoplasias , Humanos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Hipóxia , Transdução de Sinais , Microambiente Tumoral , Neoplasias/tratamento farmacológico , Neoplasias/etiologia , Hipóxia Celular
13.
Mol Cancer ; 22(1): 110, 2023 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-37443114

RESUMO

BACKGROUND: Drugs targeting the spindle assembly checkpoint (SAC), such as inhibitors of Aurora kinase B (AURKB) and dual specific protein kinase TTK, are in different stages of clinical development. However, cell response to SAC abrogation is poorly understood and there are no markers for patient selection. METHODS: A panel of 53 tumor cell lines of different origins was used. The effects of drugs were analyzed by MTT and flow cytometry. Copy number status was determined by FISH and Q-PCR; mRNA expression by nCounter and RT-Q-PCR and protein expression by Western blotting. CRISPR-Cas9 technology was used for gene knock-out (KO) and a doxycycline-inducible pTRIPZ vector for ectopic expression. Finally, in vivo experiments were performed by implanting cultured cells or fragments of tumors into immunodeficient mice. RESULTS: Tumor cells and patient-derived xenografts (PDXs) sensitive to AURKB and TTK inhibitors consistently showed high expression levels of BH3-interacting domain death agonist (BID), while cell lines and PDXs with low BID were uniformly resistant. Gene silencing rendered BID-overexpressing cells insensitive to SAC abrogation while ectopic BID expression in BID-low cells significantly increased sensitivity. SAC abrogation induced activation of CASP-2, leading to cleavage of CASP-3 and extensive cell death only in presence of high levels of BID. Finally, a prevalence study revealed high BID mRNA in 6% of human solid tumors. CONCLUSIONS: The fate of tumor cells after SAC abrogation is driven by an AURKB/ CASP-2 signaling mechanism, regulated by BID levels. Our results pave the way to clinically explore SAC-targeting drugs in tumors with high BID expression.


Assuntos
Neoplasias , Proteínas Serina-Treonina Quinases , Humanos , Animais , Camundongos , Proteínas Serina-Treonina Quinases/genética , Aurora Quinase B/genética , Aurora Quinase B/metabolismo , Pontos de Checagem da Fase M do Ciclo Celular , Linhagem Celular Tumoral , RNA Mensageiro , Neoplasias/tratamento farmacológico , Neoplasias/genética , Proteínas Tirosina Quinases/metabolismo , Proteínas de Ciclo Celular/genética
14.
J Neuroinflammation ; 20(1): 194, 2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37633912

RESUMO

BACKGROUND: Bruton's tyrosine kinase (BTK) is a key signaling node in B cell receptor (BCR) and Fc receptor (FcR) signaling. BTK inhibitors (BTKi) are an emerging oral treatment option for patients suffering from multiple sclerosis (MS). Remibrutinib (LOU064) is a potent, highly selective covalent BTKi with a promising preclinical and clinical profile for MS and other autoimmune or autoallergic indications. METHODS: The efficacy and mechanism of action of remibrutinib was assessed in two different experimental autoimmune encephalomyelitis (EAE) mouse models for MS. The impact of remibrutinib on B cell-driven EAE pathology was determined after immunization with human myelin oligodendrocyte glycoprotein (HuMOG). The efficacy on myeloid cell and microglia driven neuroinflammation was determined in the RatMOG EAE. In addition, we assessed the relationship of efficacy to BTK occupancy in tissue, ex vivo T cell response, as well as single cell RNA-sequencing (scRNA-seq) in brain and spinal cord tissue. RESULTS: Remibrutinib inhibited B cell-dependent HuMOG EAE in dose-dependent manner and strongly reduced neurological symptoms. At the efficacious oral dose of 30 mg/kg, remibrutinib showed strong BTK occupancy in the peripheral immune organs and in the brain of EAE mice. Ex vivo MOG-specific T cell recall response was reduced, but not polyclonal T cell response, indicating absence of non-specific T cell inhibition. Remibrutinib also inhibited RatMOG EAE, suggesting that myeloid cell and microglia inhibition contribute to its efficacy in EAE. Remibrutinib did not reduce B cells, total Ig levels nor MOG-specific antibody response. In brain and spinal cord tissue a clear anti-inflammatory effect in microglia was detected by scRNA-seq. Finally, remibrutinib showed potent inhibition of in vitro immune complex-driven inflammatory response in human microglia. CONCLUSION: Remibrutinib inhibited EAE models by a two-pronged mechanism based on inhibition of pathogenic B cell autoreactivity, as well as direct anti-inflammatory effects in microglia. Remibrutinib showed efficacy in both models in absence of direct B cell depletion, broad T cell inhibition or reduction of total Ig levels. These findings support the view that remibrutinib may represent a novel treatment option for patients with MS.


Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Humanos , Animais , Camundongos , Esclerose Múltipla/tratamento farmacológico , Doenças Neuroinflamatórias , Células Mieloides , Encefalomielite Autoimune Experimental/tratamento farmacológico , Tirosina Quinase da Agamaglobulinemia , Complexo Antígeno-Anticorpo , Anti-Inflamatórios
15.
J Transl Med ; 21(1): 414, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-37365600

RESUMO

BACKGROUND: Enumeration of circulating tumor cells (CTCs) has proven clinical significance for monitoring patients with metastatic cancers. Multiplexed gene expression profiling of CTCs is a potential tool for assessing disease status and monitoring treatment response. The Parsortix® technology enables the capture and harvest of CTCs from blood based on cell size and deformability. The HyCEAD™ (Hybrid Capture Enrichment Amplification and Detection) assay enables simultaneous amplification of short amplicons for up to 100 mRNA targets, and the Ziplex™ instrument quantifies the amplicons for highly sensitive gene expression profiling down to single cell levels. The aim of the study was to functionally assess this system. METHODS: The HyCEAD/Ziplex platform was used to quantify the expression levels for 72 genes using as little as 20 pg of total RNA or a single cultured tumor cell. Assay performance was evaluated using cells or total RNA spiked into Parsortix harvests of healthy donor blood. The assay was also evaluated using total RNA obtained from Parsortix harvests of blood from metastatic breast cancer (MBC) patients or healthy volunteers (HVs). RESULTS: Using genes with low expression in WBC RNA and/or in unspiked Parsortix harvests from HVs, the assay distinguished between the different breast cancer and ovarian cancer cell lines with as little as 20 pg of total RNA (equivalent to a single cell) in the presence of 1 ng of WBC RNA. Single cultured cells spiked into Parsortix harvests from 10 mL of HV blood were also detected and distinguished from each other. CVs from repeatability experiments were less than 20%. Hierarchical clustering of clinical samples differentiated most MBC patients from HVs. CONCLUSION: HyCEAD/Ziplex provided sensitive quantification of expression of 72 genes from 20 pg of total RNA from cultured tumor cell lines or from single cultured tumor cells spiked into lysates from Parsortix harvests of HV blood. The HyCEAD/Ziplex platform enables the quantification of selected genes in the presence of residual nucleated blood cells in Parsortix harvests. The HyCEAD/Ziplex platform is an effective tool for multiplexed molecular characterization of mRNA in small numbers of tumor cells harvested from blood.


Assuntos
Neoplasias da Mama , Células Neoplásicas Circulantes , Humanos , Feminino , Células Neoplásicas Circulantes/patologia , Neoplasias da Mama/patologia , Perfilação da Expressão Gênica , RNA Mensageiro/metabolismo , RNA , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo
16.
IUBMB Life ; 75(1): 40-54, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35499745

RESUMO

The hypoxic tumour microenvironment (hTME), arising from inadequate and chaotic vascularity, can present a major obstacle for the treatment of solid tumours. Hypoxic tumour cells compromise responses to treatment since they can generate resistance to radiotherapy, chemotherapy and immunotherapy. The hTME impairs the delivery of a range of anti-cancer drugs, creates routes for metastasis and exerts selection pressures for aggressive phenotypes; these changes potentially occur within an immunosuppressed environment. Therapeutic strategies aimed at the hTME include targeting the molecular changes associated with hypoxia. An alternative approach is to exploit the prevailing lack of oxygen as a principle for the selective activation of prodrugs to target cellular components within the hTME. This review focuses on the design concepts and rationale for the use of unidirectional Hypoxia-Activated Prodrugs (uHAPs) to target the hTME as exemplified by the uHAPs AQ4N and OCT1002. These agents undergo irreversible reduction in a hypoxic environment to active forms that target DNA topoisomerase IIα (TOP2A). This nuclear enzyme is essential for cell division and is a recognised chemotherapeutic target. An activated uHAP interacts with the enzyme-DNA complex to induce DNA damage, cell cycle arrest and tumour cell death. uHAPs are designed to overcome the shortcomings of conventional HAPs and offer unique pharmacodynamic properties for effective targeting of TOP2A in the hTME. uHAP therapy in combination with standard of care treatments has the potential to enhance outcomes by co-addressing the therapeutic challenge presented by the hTME.


Assuntos
Neoplasias , Pró-Fármacos , Humanos , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , Microambiente Tumoral , Hipóxia Celular , Neoplasias/tratamento farmacológico , Neoplasias/genética , Hipóxia/tratamento farmacológico , DNA Topoisomerases/farmacologia
17.
Chem Rev ; 121(6): 3297-3351, 2021 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32692162

RESUMO

There has been huge progress in the discovery of targeted cancer therapies in recent years. However, even for the most successful and impactful cancer drugs which have been approved, both innate and acquired mechanisms of resistance are commonplace. These emerging mechanisms of resistance have been studied intensively, which has enabled drug discovery scientists to learn how it may be possible to overcome such resistance in subsequent generations of treatments. In some cases, novel drug candidates have been able to supersede previously approved agents; in other cases they have been used sequentially or in combinations with existing treatments. This review summarizes the current field in terms of the challenges and opportunities that cancer resistance presents to drug discovery scientists, with a focus on small molecule therapeutics. As part of this review, common themes and approaches have been identified which have been utilized to successfully target emerging mechanisms of resistance. This includes the increase in target potency and selectivity, alternative chemical scaffolds, change of mechanism of action (covalents, PROTACs), increases in blood-brain barrier permeability (BBBP), and the targeting of allosteric pockets. Finally, wider approaches are covered such as monoclonal antibodies (mAbs), bispecific antibodies, antibody drug conjugates (ADCs), and combination therapies.


Assuntos
Anticorpos Monoclonais/química , Antineoplásicos/química , Imunoconjugados/química , Sítio Alostérico , Animais , Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica , Barreira Hematoencefálica/metabolismo , Desenho de Fármacos , Resistencia a Medicamentos Antineoplásicos , Humanos , Imunoconjugados/farmacologia , Modelos Moleculares , Medicina de Precisão , Ligação Proteica , Conformação Proteica , Transdução de Sinais , Relação Estrutura-Atividade
18.
BJOG ; 130(11): 1346-1354, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37039256

RESUMO

OBJECTIVE: To develop core outcome sets (COS) for miscarriage management and prevention. DESIGN: Modified Delphi survey combined with a consensus development meeting. SETTING: International. POPULATION: Stakeholder groups included healthcare providers, international experts, researchers, charities and couples with lived experience of miscarriage from 15 countries: 129 stakeholders for miscarriage management and 437 for miscarriage prevention. METHODS: Modified Delphi method and modified nominal group technique. RESULTS: The final COS for miscarriage management comprises six outcomes: efficacy of treatment, heavy vaginal bleeding, pelvic infection, maternal death, treatment or procedure-related complications, and patient satisfaction. The final COS for miscarriage prevention comprises 12 outcomes: pregnancy loss <24 weeks' gestation, live birth, gestation at birth, pre-term birth, congenital abnormalities, fetal growth restriction, maternal (antenatal) complications, compliance with intervention, patient satisfaction, maternal hospitalisation, neonatal or infant hospitalisation, and neonatal or infant death. Other outcomes identified as important were mental health-related outcomes, future fertility and health economic outcomes. CONCLUSIONS: This study has developed two core outcome sets, through robust methodology, that should be implemented across future randomised trials and systematic reviews in miscarriage management and prevention. This work will help to standardise outcome selection, collection and reporting, and improve the quality and safety of future studies in miscarriage.


Assuntos
Aborto Espontâneo , Morte Materna , Recém-Nascido , Gravidez , Humanos , Feminino , Aborto Espontâneo/prevenção & controle , Consenso , Retardo do Crescimento Fetal/terapia , Projetos de Pesquisa , Técnica Delphi , Avaliação de Resultados em Cuidados de Saúde , Resultado do Tratamento
19.
Oecologia ; 202(3): 481-495, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37368022

RESUMO

Multi-factor experiments suggest that interactions among environmental changes commonly influence biodiversity and community composition. However, most field experiments manipulate only single factors. Soil food webs are critical to ecosystem health and may be particularly sensitive to interactions among environmental changes that include soil warming, eutrophication, and altered precipitation. Here, we asked how environmental changes interacted to alter soil nematode communities in a northern Chihuahuan Desert grassland. Factorial manipulations of nitrogen, winter rainfall, and nighttime warming matched predictions for regional environmental change. Warming reduced nematode diversity by 25% and genus-level richness by 32%, but declines dissipated with additional winter rain, suggesting that warming effects occurred via drying. Interactions between precipitation and nitrogen also altered nematode community composition, but only weakly affected total nematode abundance, indicating that most change involved reordering of species abundances. Specifically, under ambient precipitation, nitrogen fertilizer reduced bacterivores by 68% and herbivores by 73%, but did not affect fungivores. In contrast, under winter rain addition, nitrogen fertilization increased bacterivores by 95%, did not affect herbivores, and doubled fungivore abundance. Rain can reduce soil nitrogen availability and increase turnover in the microbial loop, potentially promoting the recovery of nematode populations overwhelmed by nitrogen eutrophication. Nematode communities were not tightly coupled to plant community composition and may instead track microbes, including biocrusts or decomposers. Our results highlight the importance of interactions among environmental change stressors for shaping the composition and function of soil food webs in drylands.


Assuntos
Nematoides , Solo , Animais , Ecossistema , Cadeia Alimentar , Nitrogênio , Microbiologia do Solo
20.
Pharmacoepidemiol Drug Saf ; 32(2): 238-247, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36070795

RESUMO

PURPOSE: Infection is a major complication following joint replacement (JR) surgery. However, little data exist regarding antibiotic utilisation following primary JR and how use changes with subsequent revision surgery. This study aimed to examine variation in antibiotic utilisation rates before and after hip replacement surgery in those revised for infection, revised for other reasons and those without revision. METHODS: This retrospective cohort analysis used linked data from the Australian Orthopaedic Association National Joint Replacement Registry and Australian Government Pharmaceutical Benefits Scheme. Patients were included if undergoing total hip replacement (THR) for osteoarthritis in private hospitals between 2002 and 2017. Three groups were examined: primary THR with no subsequent revision (n = 102 577), primary THR with a subsequent revision for reasons other than periprosthetic joint infection (PJI) (n = 3156) and primary THR with a subsequent revision for PJI (n = 520). Monthly antibiotic utilisation rates and prevalence rate ratios (PRRs) with 95% confidence intervals (CIs) were calculated in the 2 years pre- and post-THR. RESULTS: Prior to primary THR antibiotic utilisation was 9%-10%. After primary THR, antibiotic utilisation rates were higher among patients revised for PJI (PRR 1.69, 95% CI 1.60-1.79) compared to non-revised patients, while the utilisation rate was lower in patients revised for reasons other than infection (PRR 0.96, 95% CI 0.93-0.98). For those revised for infection, antibiotic utilisation post-revision surgery was two times higher than those revised for other reasons (PRR 2.16, 95% CI 2.08-2.23). Utilisation of injectable antibiotics including, vancomycin, flucloxacillin and cephazolin was higher in those revised for PJI patients 0-2 weeks following surgery but not in those revised for other reasons compared to the non-revised group. CONCLUSIONS: Ongoing antibiotic utilisation after primary surgery may be an early signal of problems with the THR and should be a prompt for primary care physicians to refer patients to specialists for further appropriate investigations and management.


Assuntos
Artroplastia de Quadril , Ortopedia , Infecções Relacionadas à Prótese , Humanos , Estudos de Coortes , Estudos Retrospectivos , Antibacterianos , Reoperação , Infecções Relacionadas à Prótese/cirurgia , Austrália , Sistema de Registros
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