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The immunosuppressive tumor microenvironment (TME) is a major barrier to immunotherapy. Within solid tumors, why monocytes preferentially differentiate into immunosuppressive tumor-associated macrophages (TAMs) rather than immunostimulatory dendritic cells (DCs) remains unclear. Using multiple murine sarcoma models, we find that the TME induces tumor cells to produce retinoic acid (RA), which polarizes intratumoral monocyte differentiation toward TAMs and away from DCs via suppression of DC-promoting transcription factor Irf4. Genetic inhibition of RA production in tumor cells or pharmacologic inhibition of RA signaling within TME increases stimulatory monocyte-derived cells, enhances T cell-dependent anti-tumor immunity, and synergizes with immune checkpoint blockade. Furthermore, an RA-responsive gene signature in human monocytes correlates with an immunosuppressive TME in multiple human tumors. RA has been considered as an anti-cancer agent, whereas our work demonstrates its tumorigenic capability via myeloid-mediated immune suppression and provides proof of concept for targeting this pathway for tumor immunotherapy.
Assuntos
Monócitos/imunologia , Tretinoína/metabolismo , Microambiente Tumoral/imunologia , Animais , Carcinogênese/patologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/imunologia , Linhagem Celular Tumoral , Células Dendríticas/imunologia , Humanos , Terapia de Imunossupressão/métodos , Imunoterapia/métodos , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/metabolismoRESUMO
Caloric restriction that promotes weight loss is an effective strategy for treating non-alcoholic fatty liver disease and improving insulin sensitivity in people with type 2 diabetes1. Despite its effectiveness, in most individuals, weight loss is usually not maintained partly due to physiological adaptations that suppress energy expenditure, a process known as adaptive thermogenesis, the mechanistic underpinnings of which are unclear2,3. Treatment of rodents fed a high-fat diet with recombinant growth differentiating factor 15 (GDF15) reduces obesity and improves glycaemic control through glial-cell-derived neurotrophic factor family receptor α-like (GFRAL)-dependent suppression of food intake4-7. Here we find that, in addition to suppressing appetite, GDF15 counteracts compensatory reductions in energy expenditure, eliciting greater weight loss and reductions in non-alcoholic fatty liver disease (NAFLD) compared to caloric restriction alone. This effect of GDF15 to maintain energy expenditure during calorie restriction requires a GFRAL-ß-adrenergic-dependent signalling axis that increases fatty acid oxidation and calcium futile cycling in the skeletal muscle of mice. These data indicate that therapeutic targeting of the GDF15-GFRAL pathway may be useful for maintaining energy expenditure in skeletal muscle during caloric restriction.
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Metabolismo Energético , Fator 15 de Diferenciação de Crescimento , Músculo Esquelético , Redução de Peso , Animais , Humanos , Camundongos , Depressores do Apetite/metabolismo , Depressores do Apetite/farmacologia , Depressores do Apetite/uso terapêutico , Restrição Calórica , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica , Ingestão de Alimentos/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Fator 15 de Diferenciação de Crescimento/metabolismo , Fator 15 de Diferenciação de Crescimento/farmacologia , Fator 15 de Diferenciação de Crescimento/uso terapêutico , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/terapia , Receptores Adrenérgicos beta/metabolismo , Redução de Peso/efeitos dos fármacosRESUMO
An ensemble of atoms can operate as a quantum sensor by placing atoms in a superposition of two different states. Upon measurement of the sensor, each atom is individually projected into one of the two states. Creating quantum correlations between the atoms, that is entangling them, could lead to resolutions surpassing the standard quantum limit1-3 set by projections of individual atoms. Large amounts of entanglement4-6 involving the internal degrees of freedom of laser-cooled atomic ensembles4-16 have been generated in collective cavity quantum-electrodynamics systems, in which many atoms simultaneously interact with a single optical cavity mode. Here we report a matter-wave interferometer in a cavity quantum-electrodynamics system of 700 atoms that are entangled in their external degrees of freedom. In our system, each individual atom falls freely under gravity and simultaneously traverses two paths through space while entangled with the other atoms. We demonstrate both quantum non-demolition measurements and cavity-mediated spin interactions for generating squeezed momentum states with directly observed sensitivity [Formula: see text] dB and [Formula: see text] dB below the standard quantum limit, respectively. We successfully inject an entangled state into a Mach-Zehnder light-pulse interferometer with directly observed sensitivity [Formula: see text] dB below the standard quantum limit. The combination of particle delocalization and entanglement in our approach may influence developments of enhanced inertial sensors17,18, searches for new physics, particles and fields19-23, future advanced gravitational wave detectors24,25 and accessing beyond mean-field quantum many-body physics26-30.
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ABSTRACT: Posttransplant lymphoproliferative disorder (PTLD) is a rare complication of solid organ transplantation, and cytotoxic chemotherapy is associated with treatment-related morbidity and mortality. Current treatment takes a sequential, risk-stratified approach, and patients with low-risk disease after initial immunotherapy can avoid escalation to immunochemotherapy. TIDaL is a prospective, single-arm phase 2 trial investigating the activity and tolerability of ibrutinib combined with risk-stratified therapy for first-line treatment of PTLD. Eligible patients were adults with newly diagnosed CD20+ B-cell PTLD after solid organ transplant and performance status 0 to 2. Initial treatment comprised 49 days of ibrutinib 560 mg once daily, with 4 doses of weekly rituximab. Treatment response on interim scan and baseline International Prognostic Index were used to allocate patients to either a low-risk arm (who continued ibrutinib, alongside 4 further doses of 3-weekly rituximab) or high-risk (escalation to rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone [R-CHOP] immunochemotherapy, with ibrutinib continuing in patients aged <65 years). The primary outcome was complete response on interim scan, achieved by 11 of 38 patients (29%; 95% confidence interval [CI], 15-46). This did not reach the prespecified threshold for clinically significant activity. Secondary outcomes included allocation to the low-risk arm (41% of patients), 2-year progression-free survival (58%; 95% CI, 44-76), and 2-year overall survival (76%; 95% CI, 63-91). Adverse events were mostly hematological, gastrointestinal, and infective. Although TIDaL does not support adding ibrutinib into first-line treatment of PTLD, increasing the proportion of patients who can be treated without cytotoxic chemotherapy remains an important aim of future research. This trial was registered at www.clinicaltrials.gov as #ISRCTN32667607.
Assuntos
Adenina , Protocolos de Quimioterapia Combinada Antineoplásica , Transtornos Linfoproliferativos , Piperidinas , Rituximab , Humanos , Piperidinas/uso terapêutico , Piperidinas/efeitos adversos , Piperidinas/administração & dosagem , Pessoa de Meia-Idade , Feminino , Masculino , Adenina/análogos & derivados , Adenina/uso terapêutico , Transtornos Linfoproliferativos/tratamento farmacológico , Transtornos Linfoproliferativos/etiologia , Idoso , Adulto , Rituximab/efeitos adversos , Rituximab/administração & dosagem , Rituximab/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Transplante de Órgãos/efeitos adversos , Ciclofosfamida/administração & dosagem , Ciclofosfamida/uso terapêutico , Ciclofosfamida/efeitos adversos , Vincristina/administração & dosagem , Vincristina/efeitos adversos , Vincristina/uso terapêutico , Doxorrubicina/efeitos adversos , Doxorrubicina/uso terapêutico , Doxorrubicina/administração & dosagem , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Prednisona/uso terapêutico , Estudos Prospectivos , Pirazóis/uso terapêutico , Pirazóis/efeitos adversos , Pirazóis/administração & dosagemRESUMO
ABSTRACT: Plasmablastic lymphoma (PBL) is a rare and aggressive non-Hodgkin lymphoma associated with immunodeficiency, characterized by uncertain treatment approaches and an unfavorable prognosis. We conducted a multicenter, international, retrospective cohort study, aiming to characterize the clinical features, risk factors, and outcomes of patients with PBL. Data were collected from 22 institutions across 4 countries regarding patients diagnosed with PBL between 1 January 1999 and 31 December 2020. Survival risk factors were analyzed using both univariate and multivariate regression models. Overall survival (OS) was calculated using Kaplan-Meier statistics. First-line treatment regimens were stratified into standard- and higher-intensity regimens, and based on whether they incorporated a proteasome inhibitor (PI). A total of 281 patients (median age, 55 years) were included. Immunodeficiency of any kind was identified in 144 patients (51%), and 99 patients (35%) had HIV-positive results. The 5-year OS for the entire cohort was 36% (95% confidence interval, 30%-42%). In multivariate analysis, inferior OS was associated with Epstein-Barr virus-negative lymphoma, poor performance status, advanced stage, and bone marrow involvement. In an independent univariate analysis, the international prognostic index was associated with OS outcomes. Neither immunosuppression nor HIV infection, specifically, influenced OS. Among patients treated with curative intent (n = 234), the overall response rate was 72%. Neither the intensity of the treatment regimen nor the inclusion of PIs in first-line therapy was associated with OS. In this large retrospective study of patients with PBL, we identified novel risk factors for survival. PBL remains a challenging disease with poor long-term outcomes.
Assuntos
Infecções por Vírus Epstein-Barr , Infecções por HIV , Linfoma Plasmablástico , Humanos , Pessoa de Meia-Idade , Linfoma Plasmablástico/patologia , Estudos Retrospectivos , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4 , PrognósticoRESUMO
Infections by Human T cell Leukaemia Virus type 1 (HTLV-1) persist for the lifetime of the host by integrating into the genome of CD4+ T cells. Proviral gene expression is essential for proviral survival and the maintenance of the proviral load, through the pro-proliferative changes it induces in infected cells. Despite their role in HTLV-1 infection and a persistent cytotoxic T lymphocyte response raised against the virus, proviral transcripts from the sense-strand are rarely detected in fresh cells extracted from the peripheral blood, and have recently been found to be expressed intermittently by a small subset of cells at a given time. Ex vivo culture of infected cells prompts synchronised proviral expression in infected cells from peripheral blood, allowing the study of factors involved in reactivation in primary cells. Here, we used bulk RNA-seq to examine the host transcriptome over six days in vitro, following proviral reactivation in primary peripheral CD4+ T cells isolated from subjects with non-malignant HTLV-1 infection. Infected cells displayed a conserved response to reactivation, characterised by discrete stages of gene expression, cell division and subsequently horizontal transmission of the virus. We observed widespread changes in Polycomb gene expression following reactivation, including an increase in PRC2 transcript levels and diverse changes in the expression of PRC1 components. We hypothesize that these transcriptional changes constitute a negative feedback loop that maintains proviral latency by re-deposition of H2AK119ub1 following the end of proviral expression. Using RNAi, we found that certain deubiquitinases, BAP1, USP14 and OTUD5 each promote proviral transcription. These data demonstrate the detailed trajectory of HTLV-1 proviral reactivation in primary HTLV-1-carrier lymphocytes and the impact on the host cell.
Assuntos
Infecções por HTLV-I , Vírus Linfotrópico T Tipo 1 Humano , Humanos , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Provírus/genética , Transcriptoma , Linfócitos T CD4-Positivos , Carga Viral , Ubiquitina Tiolesterase/metabolismoRESUMO
Fuel interactions in contracting muscle represent a complex interplay between enzymes regulating carbohydrate and fatty acid catabolism, converging in the mitochondrial matrix. While increasing exercise intensity promotes carbohydrate use at the expense of fatty acid oxidation, the mechanisms underlying this effect remain poorly elucidated. As a potential explanation, we investigated whether exercise-induced reductions in intramuscular pH (acidosis) attenuate carnitine palmitoyltransferase-I (CPT-I)-supported bioenergetics, the rate-limiting step for fatty acid oxidation within mitochondria. Specifically, we assessed the effect of a physiologically relevant reduction in pH (pH 7.2 versus 6.8) on single and mixed substrate respiratory responses in murine skeletal muscle isolated mitochondria and permeabilized fibers. While pH did not influence oxidative phosphorylation stoichiometry (ADP/O ratios), coupling efficiency, oxygen affinity, or ADP respiratory responses, acidosis impaired lipid bioenergetics by attenuating respiration with L-carnitine and palmitoyl-CoA, while enhancing the inhibitory effect of malonyl-CoA on CPT-I. These acidotic effects were largely retained following a single bout of intense exercise. At rest, pyruvate and succinate-supported respiration were also impaired by acidosis. However, providing more pyruvate and ADP at pH 6.8 to model increases in glycolytic flux and ATP turnover with intense exercise overcame the acidotic attenuation of carbohydrate-linked oxidative phosphorylation. Importantly, this situation is fundamentally different from lipids where CPT-I substrate sensitivity and availability is impaired at higher power outputs suggesting lipid metabolism may be more susceptible to the effects of acidosis, possibly contributing to fuel shifts with increasing exercise intensity.
Assuntos
Acidose , Carnitina O-Palmitoiltransferase , Metabolismo Energético , Metabolismo dos Lipídeos , Condicionamento Físico Animal , Animais , Camundongos , Carnitina O-Palmitoiltransferase/metabolismo , Ácidos Graxos/metabolismo , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Oxirredução , Piruvatos/metabolismo , Piruvatos/farmacologia , Acidose/metabolismo , Camundongos Endogâmicos C57BL , Condicionamento Físico Animal/fisiologia , Concentração de Íons de Hidrogênio , Metabolismo dos Carboidratos , Transporte de ElétronsRESUMO
Patients affected by multiple myeloma (MM) have an increased risk of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) infection and subsequent coronavirus (20)19 disease (COVID-19)-related death. The changing epidemiological and therapeutic scenarios suggest that there has been an improvement in severity and survival of COVID-19 during the different waves of the pandemic in the general population, but this has not been investigated yet in MM patients. Here we analyzed a large cohort of 1221 patients with MM and confirmed SARS-CoV-2 infection observed between February 2020, and August 2022, in the EPICOVIDEHA registry from 132 centers around the world. Median follow-up was 52 days for the entire cohort and 83 days for survivors. Three-hundred and three patients died (24%) and COVID-19 was the primary reason for death of around 89% of them. Overall survival (OS) was significantly higher in vaccinated patients with both stable and active MM versus unvaccinated, while only a trend favoring vaccinated patients was observed in subjects with responsive MM. Vaccinated patients with at least 2 doses showed a better OS than those with one or no vaccine dose. Overall, according to pandemic waves, mortality rate decreased over time from 34% to 10%. In multivariable analysis, age, renal failure, active disease, hospital, and intensive care unit admission, were independently associated with a higher number of deaths, while a neutrophil count above 0.5 × 109 /L was found to be protective. This data suggests that MM patients remain at risk of SARS-CoV-2 infection even in the vaccination era, but their clinical outcome, in terms of OS, has progressively improved throughout the different viral phases of the pandemic.
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COVID-19 , Mieloma Múltiplo , Humanos , SARS-CoV-2 , Pandemias , Mieloma Múltiplo/terapia , Sistema de RegistrosRESUMO
OBJECTIVE: The majority of high-grade serous carcinomas (HGSC) of the ovary, fallopian tube, and peritoneum arise from the precursor lesion called serous tubal intraepithelial carcinoma (STIC). It has been postulated that cells from STICs exfoliate into the peritoneal cavity and give rise to peritoneal HGSC several years later. While co-existent STICs and HGSCs have been reported to share similarities in their mutational profiles, clonal relationship between temporally distant STICs and HGSCs have been infrequently studied and the natural history of STICs remains poorly understood. METHODS: We performed focused searches in two national databases from the Netherlands and identified a series of BRCA1/2 germline pathogenic variant (GPV) carriers (n = 7) who had STIC, and no detectable invasive carcinoma, at the time of their risk-reducing salpingo-oophorectomy (RRSO), and later developed peritoneal HGSC. The clonal relationship between these STICs and HGSCs was investigated by comparing their genetic mutational profile by performing next-generation targeted sequencing. RESULTS: Identical pathogenic mutations and loss of heterozygosity of TP53 were identified in the STICs and HGSCs of five of the seven patients (71%), confirming the clonal relationship of the lesions. Median interval for developing HGSC after RRSO was 59 months (range: 24-118 months). CONCLUSION: Our results indicate that cells from STIC can shed into the peritoneal cavity and give rise to HGSC after long lag periods in BRCA1/2 GPV carriers, and argues in favor of the hypothesis that STIC lesions may metastasize.
Assuntos
Cistadenocarcinoma Seroso , Neoplasias das Tubas Uterinas , Neoplasias Ovarianas , Salpingo-Ooforectomia , Humanos , Feminino , Neoplasias das Tubas Uterinas/genética , Neoplasias das Tubas Uterinas/patologia , Neoplasias das Tubas Uterinas/cirurgia , Neoplasias das Tubas Uterinas/prevenção & controle , Cistadenocarcinoma Seroso/genética , Cistadenocarcinoma Seroso/patologia , Cistadenocarcinoma Seroso/cirurgia , Cistadenocarcinoma Seroso/prevenção & controle , Pessoa de Meia-Idade , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/cirurgia , Neoplasias Ovarianas/prevenção & controle , Adulto , Neoplasias Peritoneais/genética , Neoplasias Peritoneais/patologia , Carcinoma in Situ/genética , Carcinoma in Situ/patologia , Carcinoma in Situ/cirurgia , Mutação em Linhagem Germinativa , Genes BRCA2 , Proteína BRCA2/genética , Proteína BRCA1/genética , Genes BRCA1RESUMO
Sustainability and circularity are key issues facing the global polymer industry. The search for biodegradable and environmentally-friendly polymers that can replace conventional materials is a difficult challenge that has been met with limited success. Alternatives must be cost-effective, scalable, and provide equivalent performance. We report that latexes made by the conventional emulsion polymerization of vinyl acetate and functional vinyl ester monomers are efficient thickeners for consumer products and biodegrade in wastewater. This approach uses readily-available starting materials and polymerization is carried out in water at room temperature, in one pot, and generates negligible waste. Moreover, the knowledge that poly(vinyl ester)s are biodegradable will lead to the design of new green polymer materials.
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Emulsões , Emulsões/química , Polimerização , Polímeros/química , Álcalis/química , Biodegradação Ambiental , Látex/química , Compostos de Vinila/química , Águas Residuárias/químicaRESUMO
BACKGROUND: Hearing loss impacts health-related quality of life and general well-being and was identified in a Lancet report as one of the largest potentially modifiable factors for the prevention of age-related dementia. There is a lack of robust data on how cochlear implant treatment in the elderly impacts quality of life. The primary objective was to measure the change in health utility following cochlear implantation in individuals aged ≥ 60 years. METHODS: This study uniquely prospectively recruited a large multinational sample of 100 older adults (mean age 71.7 (SD7.6) range 60-91 years) with severe to profound hearing loss. In a repeated-measures design, pre and post implant outcome measures were analysed using mixed-effect models. Health utility was assessed with the Health Utilities Index Mark III (HUI3). Subjects were divided into groups of 60-64, 65-74 and 75 + years. RESULTS: At 18 months post implant, the mean HUI3 score improved by 0.13 (95%CI: 0.07-0.18 p < 0.001). There was no statistically significant difference in the HUI3 between age groups (F[2,9228] = 0.53, p = 0.59). The De Jong Loneliness scale reduced by an average of 0.61 (95%CI: 0.25-0.97 p < 0.014) and the Lawton Instrumental Activities of Daily Living Scale improved on average (1.25, 95%CI: 0.85-1.65 p < 0.001). Hearing Handicap Inventory for the Elderly Screening reduced by an average of 8.7 (95%CI: 6.7-10.8, p < 0.001) from a significant to mild-moderate hearing handicap. Age was not a statistically significant factor for any of the other measures (p > 0.20). At baseline 90% of participants had no or mild depression and there was no change in mean depression scores after implant. Categories of Auditory perception scale showed that all subjects achieved a level of speech sound discrimination without lip reading post implantation (level 4) and at least 50% could use the telephone with a known speaker. CONCLUSIONS: Better hearing improved individuals' quality of life, ability to communicate verbally and their ability to function independently. They felt less lonely and less handicapped by their hearing loss. Benefits were independent of age group. Cochlear implants should be considered as a routine treatment option for those over 60 years with bilateral severe to profound hearing loss. TRIAL REGISTRATION: ClinicalTrials.gov ( http://www. CLINICALTRIALS: gov/ ), 7 March 2017, NCT03072862.
Assuntos
Implante Coclear , Implantes Cocleares , Surdez , Perda Auditiva , Percepção da Fala , Idoso , Idoso de 80 Anos ou mais , Humanos , Atividades Cotidianas , Surdez/cirurgia , Perda Auditiva/diagnóstico , Perda Auditiva/terapia , Qualidade de Vida , Resultado do Tratamento , Pessoa de Meia-IdadeRESUMO
BackgroundHuman T-cell lymphotropic virus type 1 (HTLV-1) is a neglected virus that can cause severe disease and be transmitted from mother to child through breastfeeding. Avoidance of breastfeeding prevents 80% of vertical transmission. The United Kingdom (UK) is currently assessing whether HTLV-1-targeted antenatal screening should be implemented.AimWe aimed to assess the impact and cost-effectiveness of a targeted programme to prevent HTLV-1 vertical transmission in England and Wales.MethodsWe estimated the number of pregnant women who have high risk of HTLV-1 infection based on their or their partner's country of birth. With data from 2021, we used a mathematical model to assess cost-effectiveness of HTLV-1 antenatal screening. We also estimated the annual number of infant infections and the number that could be prevented with screening and intervention.ResultsWe estimate that ca 99,000 pregnant women in England and Wales have high risk of HTLV-1 infection. In the absence of screening, 74 (range:â¯25-211) HTLV-1 infections in infants would be expected to occur every year in England and Wales. Implementation of targeted screening would prevent 58 (range:â¯19-164) infant infections annually. The intervention is effective (incremental 0.00333 quality-adjusted life years (QALY)) and cost-saving (GBP -57.56 (EURâ¯-66.85)).ConclusionOur findings support implementation of HTLV-1 targeted antenatal screening to reduce vertical transmission from mothers to infants in the UK.
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Análise Custo-Benefício , Infecções por HTLV-I , Vírus Linfotrópico T Tipo 1 Humano , Transmissão Vertical de Doenças Infecciosas , Programas de Rastreamento , Diagnóstico Pré-Natal , Humanos , Infecções por HTLV-I/prevenção & controle , Infecções por HTLV-I/epidemiologia , Infecções por HTLV-I/transmissão , Infecções por HTLV-I/diagnóstico , Feminino , Gravidez , País de Gales/epidemiologia , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Inglaterra/epidemiologia , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Diagnóstico Pré-Natal/economia , Programas de Rastreamento/economia , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/prevenção & controle , Complicações Infecciosas na Gravidez/epidemiologia , Lactente , Recém-Nascido , AdultoRESUMO
Skeletal muscle disuse reduces muscle protein synthesis rates and induces atrophy, events associated with decreased mitochondrial respiration and increased reactive oxygen species. Given that dietary nitrate can improve mitochondrial bioenergetics, we examined whether nitrate supplementation attenuates disuse-induced impairments in mitochondrial function and muscle protein synthesis rates. Female C57Bl/6N mice were subjected to single-limb casting (3 or 7 days) and consumed drinking water with or without 1 mM sodium nitrate. Compared with the contralateral control limb, 3 days of immobilization lowered myofibrillar fractional synthesis rates (FSR, P < 0.0001), resulting in muscle atrophy. Although FSR and mitophagy-related proteins were higher in subsarcolemmal (SS) compared with intermyofibrillar (IMF) mitochondria, immobilization for 3 days decreased FSR in both SS (P = 0.009) and IMF (P = 0.031) mitochondria. Additionally, 3 days of immobilization reduced maximal mitochondrial respiration, decreased mitochondrial protein content, and increased maximal mitochondrial reactive oxygen species emission, without altering mitophagy-related proteins in muscle homogenate or isolated mitochondria (SS and IMF). Although nitrate consumption did not attenuate the decline in muscle mass or myofibrillar FSR, intriguingly, nitrate completely prevented immobilization-induced reductions in SS and IMF mitochondrial FSR. In addition, nitrate prevented alterations in mitochondrial content and bioenergetics after both 3 and 7 days of immobilization. However, in contrast to 3 days of immobilization, nitrate did not prevent the decline in SS and IMF mitochondrial FSR after 7 days of immobilization. Therefore, although nitrate supplementation was not sufficient to prevent muscle atrophy, nitrate may represent a promising therapeutic strategy to maintain mitochondrial bioenergetics and transiently preserve mitochondrial protein synthesis rates during short-term muscle disuse. KEY POINTS: Alterations in mitochondrial bioenergetics (decreased respiration and increased reactive oxygen species) are thought to contribute to muscle atrophy and reduced protein synthesis rates during muscle disuse. Given that dietary nitrate can improve mitochondrial bioenergetics, we examined whether nitrate supplementation could attenuate immobilization-induced skeletal muscle impairments in female mice. Dietary nitrate prevented short-term (3 day) immobilization-induced declines in mitochondrial protein synthesis rates, reductions in markers of mitochondrial content, and alterations in mitochondrial bioenergetics. Despite these benefits and the preservation of mitochondrial content and bioenergetics during more prolonged (7 day) immobilization, nitrate consumption did not preserve skeletal muscle mass or myofibrillar protein synthesis rates. Overall, although dietary nitrate did not prevent atrophy, nitrate supplementation represents a promising nutritional approach to preserve mitochondrial function during muscle disuse.
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Metastasis requires tumour cells to cross endothelial cell (EC) barriers using pathways similar to those used by leucocytes during inflammation. Cell surface CD99 is expressed by healthy leucocytes and ECs, and participates in inflammatory transendothelial migration (TEM). Tumour cells also express CD99, and we have analysed its role in tumour progression and cancer cell TEM. Tumour cell CD99 was required for adhesion to ECs but inhibited invasion of the endothelial barrier and migratory activity. Furthermore, CD99 depletion in tumour cells caused redistribution of the actin cytoskeleton and increased activity of the Rho GTPase CDC42, known for its role in actin remodelling and cell migration. In a xenograft model of breast cancer, tumour cell CD99 expression inhibited metastatic progression, and patient samples showed reduced expression of the CD99 gene in brain metastases compared to matched primary breast tumours. We conclude that CD99 negatively regulates CDC42 and cell migration. However, CD99 has both pro- and anti-tumour activity, and our data suggest that this results in part from its functional linkage to CDC42 and the diverse signalling pathways downstream of this Rho GTPase. This article has an associated First Person interview with the first author of the paper.
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Actinas , Neoplasias , Antígeno 12E7 , Actinas/genética , Movimento Celular/genética , Humanos , Migração Transendotelial e Transepitelial , Proteína cdc42 de Ligação ao GTP/genética , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteínas rho de Ligação ao GTP/genética , Proteínas rho de Ligação ao GTP/metabolismoRESUMO
BACKGROUND: Diabetic retinopathy (DR) is a major sight-threatening microvascular complication in individuals with diabetes. Systemic inflammation combined with oxidative stress is thought to capture most of the complexities involved in the pathology of diabetic retinopathy. A high level of neutrophil-lymphocyte ratio (NLR) is an indicator of abnormal immune system activity. Current estimates of the association of NLR with diabetes and its complications are almost entirely derived from cross-sectional studies, suggesting that the nature of the reported association may be more diagnostic than prognostic. Therefore, in the present study, we examined the utility of NLR as a biomarker to predict the incidence of DR in the Scottish population. METHODS: The incidence of DR was defined as the time to the first diagnosis of R1 or above grade in the Scottish retinopathy grading scheme from type 2 diabetes diagnosis. The effect of NLR and its interactions were explored using a competing risks survival model adjusting for other risk factors and accounting for deaths. The Fine and Gray subdistribution hazard model (FGR) was used to predict the effect of NLR on the incidence of DR. RESULTS: We analysed data from 23,531 individuals with complete covariate information. At 10 years, 8416 (35.8%) had developed DR and 2989 (12.7%) were lost to competing events (death) without developing DR and 12,126 individuals did not have DR. The median (interquartile range) level of NLR was 2.04 (1.5 to 2.7). The optimal NLR cut-off value to predict retinopathy incidence was 3.04. After accounting for competing risks at 10 years, the cumulative incidence of DR and deaths without DR were 50.7% and 21.9%, respectively. NLR was associated with incident DR in both Cause-specific hazard (CSH = 1.63; 95% CI: 1.28-2.07) and FGR models the subdistribution hazard (sHR = 2.24; 95% CI: 1.70-2.94). Both age and HbA1c were found to modulate the association between NLR and the risk of DR. CONCLUSIONS: The current study suggests that NLR has a promising potential to predict DR incidence in the Scottish population, especially in individuals less than 65 years and in those with well-controlled glycaemic status.
Assuntos
Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Humanos , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/epidemiologia , Neutrófilos , Diabetes Mellitus Tipo 2/epidemiologia , Incidência , Estudos Transversais , Linfócitos/patologia , Fatores de Risco , Escócia/epidemiologiaRESUMO
Independent supplementation with nitrate (NIT) and resveratrol (RSV) enriches various aspects of mitochondrial biology in key metabolic tissues. Although RSV is known to activate Sirt1 and initiate mitochondrial biogenesis, the metabolic benefits elicited by dietary nitrate appear to be dependent on 5'-adenosine monophosphate-activated protein kinase (AMPK)-mediated signaling events, a process also linked to the activation of Sirt1. Although the benefits of individual supplementation with these compounds have been characterized, it is unknown if co-supplementation may produce superior metabolic adaptations. Thus, we aimed to determine if treatment with combined +NIT and +RSV (+RN) could additively alter metabolic adaptations in the presence of a high-fat diet (HFD). Both +RSV and +NIT improved glucose tolerance compared with HFD (P < 0.05); however, this response was attenuated following combined +RN supplementation. Within skeletal muscle, all supplements increased mitochondrial ADP sensitivity compared with HFD (P < 0.05), without altering mitochondrial content. Although +RSV and +NIT decreased hepatic lipid deposition compared with HFD (P < 0.05), this effect was abolished with +RN, which aligned with significant reductions in Sirt1 protein content (P < 0.05) after combined treatment, in the absence of changes to mitochondrial content or function. Within epididymal white adipose tissue (eWAT), all supplements reduced crown-like structure accumulation compared with HFD (P < 0.0001) and mitochondrial reactive oxygen species (ROS) emission (P < 0.05), alongside reduced adipocyte cross-sectional area (CSA) (P < 0.05), with the greatest effect observed after +RN treatment (P = 0.0001). Although the present data suggest additive changes in adipose tissue metabolism after +RN treatment, concomitant impairments in hepatic lipid homeostasis appear to prevent improvements in whole body glucose homeostasis observed with independent treatment, which may be Sirt1 dependent.
Assuntos
Nitratos , Sirtuína 1 , Camundongos , Animais , Masculino , Resveratrol/farmacologia , Nitratos/farmacologia , Sirtuína 1/metabolismo , Suplementos Nutricionais , Dieta Hiperlipídica , Proteínas Quinases Ativadas por AMP/metabolismo , Glucose/metabolismo , LipídeosRESUMO
Small molecule heterobifunctional degraders (commonly also known as PROTACs) offer tremendous potential to deliver new therapeutics in areas of unmet medical need. To deliver on this promise, a new discipline directed at degrader design and optimization has emerged within medicinal chemistry to address a central challenge, namely how to optimize relatively large, heterobifunctional molecules for activity, whilst maintaining drug-like properties. This process involves simultaneous optimization of the three principle degrader components: E3 ubiquitin ligase ligand, linker, and protein of interest (POI) ligand. A substantial degree of commonality exists with the E3 ligase ligands typically used at the early stages of degrader development, resulting in demand for these compounds as chemical building blocks in degrader research programs. We describe herein a collation of large scale, high-yielding syntheses to access the most utilized E3 ligase ligands to support early-stage degrader development.
Assuntos
Proteínas , Ubiquitina-Proteína Ligases , Ubiquitina-Proteína Ligases/metabolismo , Proteólise , Ligantes , Proteínas/metabolismoRESUMO
OBJECTIVES: The aim of this study was to evaluate the impact of long-term sample storage on the concentrations of neopterin and neurofilament light (Nfl) in cerebrospinal fluid (CSF) samples. These are useful markers of neuroinflammation and neuronal damage and have been applied as biomarkers for several neurological diseases. However, different pre-analytical variables have potential to influence results. METHODS: Twenty-one CSF samples donated by patients with HTLV-1-associated myelopathy (HAM) and stored for up to 11 years at -80 °C were retested after three-years for neopterin (n=10) and Nfl (n=11) by ELISA. RESULTS: There was a strong correlation between the paired results (r>0.98, p<0.0001). Neopterin concentrations (nmol/L) ranged from 12.4 to 64 initially and from 11.5 to 64.4 when retested, with means (SD) of 30 (18.4) 1st test and 33 (19.1) 2nd test. Nfl concentrations (pg/mL) ranged from 79.9 to 3,733 initially and from 86.3 to 3,332, when retested with means (SD) of 1,138 (1,272) 1st test and 1,009 (1,114) at re-test. CONCLUSIONS: Storing CSF samples at -80 °C appears not to impact the quantification of neopterin and Nfl allowing confidence in the reporting of archived samples.
Assuntos
Filamentos Intermediários , Neurônios , Humanos , Neopterina/líquido cefalorraquidiano , Ensaio de Imunoadsorção Enzimática , Biomarcadores/líquido cefalorraquidiano , Proteínas de Neurofilamentos/análiseRESUMO
BACKGROUND: The Perioperative care for Older People undergoing Surgery (POPS) service model is increasingly being implemented across care providers in the English and Welsh National Health Services. OBJECTIVE: The study aimed to produce evidence regarding clinical leaders' activities to implement POPS across different service contexts and to produce generalisable recommendations for future implementation. METHODS: A qualitative interview study was undertaken across six National Health Services hospitals with established POPS services. Interview participants were recruited on the basis of their direct involvement in the implementation and leadership of the service. Data collection involved semi-structured interviews with 26 people carried out between November 2022 and May 2023. RESULTS: The implementation of POPS is often hampered by a lack of managerial and financial support, and apprehension amongst surgeons and anaesthetist about new ways of working. POPS leaders address these through five interconnected activities, each targeted at a combination of implementation factors. (i) Securing management and financial support. (ii) Professional engagement. (iii) Evidence building as a resource for demonstrating the clinical and operational benefits of POPS. (iv) Communication and engagement activities to promote and legitimise POPS to stakeholder groups. (v) Designated and distributed leadership to promote and coordinate implementation activities and to spread the service to new pathways. CONCLUSIONS: Through a combination of activities POPS can be effectively implemented across different organisational contexts. Some aspects of these activities can be guided by shared resources and learning across sites, but others require adaption to local contextual barriers and drivers.