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1.
Cell ; 186(22): 4851-4867.e20, 2023 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-37848036

RESUMEN

Post-acute sequelae of COVID-19 (PASC, "Long COVID") pose a significant global health challenge. The pathophysiology is unknown, and no effective treatments have been found to date. Several hypotheses have been formulated to explain the etiology of PASC, including viral persistence, chronic inflammation, hypercoagulability, and autonomic dysfunction. Here, we propose a mechanism that links all four hypotheses in a single pathway and provides actionable insights for therapeutic interventions. We find that PASC are associated with serotonin reduction. Viral infection and type I interferon-driven inflammation reduce serotonin through three mechanisms: diminished intestinal absorption of the serotonin precursor tryptophan; platelet hyperactivation and thrombocytopenia, which impacts serotonin storage; and enhanced MAO-mediated serotonin turnover. Peripheral serotonin reduction, in turn, impedes the activity of the vagus nerve and thereby impairs hippocampal responses and memory. These findings provide a possible explanation for neurocognitive symptoms associated with viral persistence in Long COVID, which may extend to other post-viral syndromes.


Asunto(s)
Síndrome Post Agudo de COVID-19 , Serotonina , Humanos , COVID-19/complicaciones , Progresión de la Enfermedad , Inflamación , Síndrome Post Agudo de COVID-19/sangre , Síndrome Post Agudo de COVID-19/patología , Serotonina/sangre , Virosis
2.
Nature ; 614(7947): 294-302, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36653450

RESUMEN

Recent success in training artificial agents and robots derives from a combination of direct learning of behavioural policies and indirect learning through value functions1-3. Policy learning and value learning use distinct algorithms that optimize behavioural performance and reward prediction, respectively. In animals, behavioural learning and the role of mesolimbic dopamine signalling have been extensively evaluated with respect to reward prediction4; however, so far there has been little consideration of how direct policy learning might inform our understanding5. Here we used a comprehensive dataset of orofacial and body movements to understand how behavioural policies evolved as naive, head-restrained mice learned a trace conditioning paradigm. Individual differences in initial dopaminergic reward responses correlated with the emergence of learned behavioural policy, but not the emergence of putative value encoding for a predictive cue. Likewise, physiologically calibrated manipulations of mesolimbic dopamine produced several effects inconsistent with value learning but predicted by a neural-network-based model that used dopamine signals to set an adaptive rate, not an error signal, for behavioural policy learning. This work provides strong evidence that phasic dopamine activity can regulate direct learning of behavioural policies, expanding the explanatory power of reinforcement learning models for animal learning6.


Asunto(s)
Conducta Animal , Dopamina , Aprendizaje , Vías Nerviosas , Refuerzo en Psicología , Animales , Ratones , Algoritmos , Dopamina/metabolismo , Redes Neurales de la Computación , Recompensa , Conjuntos de Datos como Asunto , Señales (Psicología) , Condicionamiento Psicológico , Movimiento , Cabeza
3.
Annu Rev Neurosci ; 43: 485-507, 2020 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-32303147

RESUMEN

Behavior is readily classified into patterns of movements with inferred common goals-actions. Goals may be discrete; movements are continuous. Through the careful study of isolated movements in laboratory settings, or via introspection, it has become clear that animals can exhibit exquisite graded specification to their movements. Moreover, graded control can be as fundamental to success as the selection of which action to perform under many naturalistic scenarios: a predator adjusting its speed to intercept moving prey, or a tool-user exerting the perfect amount of force to complete a delicate task. The basal ganglia are a collection of nuclei in vertebrates that extend from the forebrain (telencephalon) to the midbrain (mesencephalon), constituting a major descending extrapyramidal pathway for control over midbrain and brainstem premotor structures. Here we discuss how this pathway contributes to the continuous specification of movements that endows our voluntary actions with vigor and grace.


Asunto(s)
Ganglios Basales/fisiología , Conducta/fisiología , Encéfalo/fisiología , Movimiento/fisiología , Vías Nerviosas/fisiología , Animales , Humanos , Neuronas/fisiología
4.
Development ; 151(3)2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37982461

RESUMEN

Early organogenesis represents a key step in animal development, during which pluripotent cells diversify to initiate organ formation. Here, we sampled 300,000 single-cell transcriptomes from mouse embryos between E8.5 and E9.5 in 6-h intervals and combined this new dataset with our previous atlas (E6.5-E8.5) to produce a densely sampled timecourse of >400,000 cells from early gastrulation to organogenesis. Computational lineage reconstruction identified complex waves of blood and endothelial development, including a new programme for somite-derived endothelium. We also dissected the E7.5 primitive streak into four adjacent regions, performed scRNA-seq and predicted cell fates computationally. Finally, we defined developmental state/fate relationships by combining orthotopic grafting, microscopic analysis and scRNA-seq to transcriptionally determine cell fates of grafted primitive streak regions after 24 h of in vitro embryo culture. Experimentally determined fate outcomes were in good agreement with computationally predicted fates, demonstrating how classical grafting experiments can be revisited to establish high-resolution cell state/fate relationships. Such interdisciplinary approaches will benefit future studies in developmental biology and guide the in vitro production of cells for organ regeneration and repair.


Asunto(s)
Gastrulación , Organogénesis , Ratones , Animales , Diferenciación Celular , Organogénesis/genética , Línea Primitiva , Endotelio , Embrión de Mamíferos , Mamíferos
5.
Proc Natl Acad Sci U S A ; 120(44): e2311946120, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37871215

RESUMEN

The T-box transcription factor Eomesodermin (Eomes), also known as Tbr2, plays essential roles in the early mouse embryo. Loss-of-function mutant embryos arrest at implantation due to Eomes requirements in the trophectoderm cell lineage. Slightly later, expression in the visceral endoderm promotes anterior visceral endoderm formation and anterior-posterior axis specification. Early induction in the epiblast beginning at day 6 is necessary for nascent mesoderm to undergo epithelial to mesenchymal transition (EMT). Eomes acts in a temporally and spatially restricted manner to sequentially specify the yolk sac haemogenic endothelium, cardiac mesoderm, definitive endoderm, and axial mesoderm progenitors during gastrulation. Little is known about the underlying molecular mechanisms governing Eomes actions during the formation of these distinct progenitor cell populations. Here, we introduced a degron-tag and mCherry reporter sequence into the Eomes locus. Our experiments analyzing homozygously tagged embryonic stem cells and embryos demonstrate that the degron-tagged Eomes protein is fully functional. dTAG (degradation fusion tag) treatment in vitro results in rapid protein degradation and recapitulates the Eomes-null phenotype. However in utero administration of dTAG resulted in variable and lineage-specific degradation, likely reflecting diverse cell type-specific Eomes expression dynamics. Finally, we demonstrate that Eomes protein rapidly recovers following dTAG wash-out in vitro. The ability to temporally manipulate Eomes protein expression in combination with cell marking by the mCherry-reporter offers a powerful tool for dissecting Eomes-dependent functional roles in these diverse cell types in the early embryo.


Asunto(s)
Transición Epitelial-Mesenquimal , Proteínas de Dominio T Box , Ratones , Animales , Proteínas de Dominio T Box/genética , Proteínas de Dominio T Box/metabolismo , Estratos Germinativos/metabolismo , Embrión de Mamíferos/metabolismo , Mesodermo/metabolismo , Endodermo/metabolismo , Regulación del Desarrollo de la Expresión Génica
6.
Mol Cell ; 66(4): 503-516.e5, 2017 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-28525742

RESUMEN

ADP-ribosylation of proteins is emerging as an important regulatory mechanism. Depending on the family member, ADP-ribosyltransferases either conjugate a single ADP-ribose to a target or generate ADP-ribose chains. Here we characterize Parp9, a mono-ADP-ribosyltransferase reported to be enzymatically inactive. Parp9 undergoes heterodimerization with Dtx3L, a histone E3 ligase involved in DNA damage repair. We show that the Dtx3L/Parp9 heterodimer mediates NAD+-dependent mono-ADP-ribosylation of ubiquitin, exclusively in the context of ubiquitin processing by E1 and E2 enzymes. Dtx3L/Parp9 ADP-ribosylates the carboxyl group of Ub Gly76. Because Gly76 is normally used for Ub conjugation to substrates, ADP-ribosylation of the Ub carboxyl terminus precludes ubiquitylation. Parp9 ADP-ribosylation activity therefore restrains the E3 function of Dtx3L. Mutation of the NAD+ binding site in Parp9 increases the DNA repair activity of the heterodimer. Moreover, poly(ADP-ribose) binding to the Parp9 macrodomains increases E3 activity. Dtx3L heterodimerization with Parp9 enables NAD+ and poly(ADP-ribose) regulation of E3 activity.


Asunto(s)
Adenosina Difosfato Ribosa/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/enzimología , Poli(ADP-Ribosa) Polimerasas/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina/metabolismo , Línea Celular Tumoral , Reparación del ADN , Células HEK293 , Humanos , Mutación , NAD/metabolismo , Proteínas de Neoplasias/genética , Neoplasias/genética , Neoplasias/patología , Poli(ADP-Ribosa) Polimerasas/genética , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Interferencia de ARN , Factores de Tiempo , Transfección , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación
7.
Cancer ; 130(20): 3426-3435, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39031642

RESUMEN

BACKGROUND: [177Lu]Lu-PSMA-617 (177Lu-PSMA-617) plus protocol-permitted standard of care (SOC) prolonged overall survival (OS) and radiographic progression-free survival (rPFS) versus SOC in patients with prostate-specific membrane antigen (PSMA)-positive metastatic castration-resistant prostate cancer (mCRPC) in the phase 3 VISION study, in addition to beneficial effects on symptomatic skeletal events (SSEs) and health-related quality of life (HRQOL). METHODS: Post hoc analyses used the full analysis set from the VISION study (N = 831) overall and by randomized treatment arm (177Lu-PSMA-617 plus SOC, n = 551; SOC, n = 280). Correlations were determined between OS and rPFS and between rPFS or OS and time to SSE or to worsening HRQOL (Functional Assessment of Cancer Therapy-Prostate [FACT-P] and 5-level EQ-5D [EQ-5D-5L]). Correlation analyses used an iterative multiple imputation copula-based approach (correlation coefficients [rho] of <0.3 were defined as weak, ≥0.3 and <0.5 as mild, ≥0.5 and <0.7 as moderate, and ≥0.7 as strong). RESULTS: In the overall population, rPFS correlated strongly with OS (rho, ≥0.7). Correlations between rPFS or OS and time to SSE without death were weak or mild. Time to worsening in the FACT-P total score and emotional and physical well-being domains correlated mildly or moderately with rPFS and moderately with OS. Correlation coefficients for time-to-worsening EQ-5D-5L scores were mild to moderate for both rPFS and OS. Correlation coefficients were similar between treatment arms. CONCLUSIONS: In this analysis of the VISION study, rPFS correlated strongly with OS but not with time to SSE or worsening HRQOL. These findings require further investigation.


Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración , Calidad de Vida , Humanos , Masculino , Neoplasias de la Próstata Resistentes a la Castración/patología , Neoplasias de la Próstata Resistentes a la Castración/mortalidad , Neoplasias de la Próstata Resistentes a la Castración/psicología , Anciano , Supervivencia sin Progresión , Persona de Mediana Edad , Lutecio/uso terapéutico , Metástasis de la Neoplasia
8.
Br J Cancer ; 130(1): 19-30, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37884682

RESUMEN

The side effects of cancer therapy continue to cause significant health and cost burden to the patient, their friends and family, and governments. A major barrier in the way in which these side effects are managed is the highly siloed mentality that results in a fragmented approach to symptom control. Increasingly, it is appreciated that many symptoms are manifestations of common underlying pathobiology, with changes in the gastrointestinal environment a key driver for many symptom sequelae. Breakdown of the mucosal barrier (mucositis) is a common and early side effect of many anti-cancer agents, known to contribute (in part) to a range of highly burdensome symptoms such as diarrhoea, nausea, vomiting, infection, malnutrition, fatigue, depression, and insomnia. Here, we outline a rationale for how, based on its already documented effects on the gastrointestinal microenvironment, medicinal cannabis could be used to control mucositis and prevent the constellation of symptoms with which it is associated. We will provide a brief update on the current state of evidence on medicinal cannabis in cancer care and outline the potential benefits (and challenges) of using medicinal cannabis during active cancer therapy.


Asunto(s)
Marihuana Medicinal , Mucositis , Neoplasias , Humanos , Marihuana Medicinal/efectos adversos , Mucositis/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Náusea/inducido químicamente , Náusea/tratamiento farmacológico , Vómitos , Microambiente Tumoral
9.
N Engl J Med ; 385(12): 1091-1103, 2021 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-34161051

RESUMEN

BACKGROUND: Metastatic castration-resistant prostate cancer remains fatal despite recent advances. Prostate-specific membrane antigen (PSMA) is highly expressed in metastatic castration-resistant prostate cancer. Lutetium-177 (177Lu)-PSMA-617 is a radioligand therapy that delivers beta-particle radiation to PSMA-expressing cells and the surrounding microenvironment. METHODS: We conducted an international, open-label, phase 3 trial evaluating 177Lu-PSMA-617 in patients who had metastatic castration-resistant prostate cancer previously treated with at least one androgen-receptor-pathway inhibitor and one or two taxane regimens and who had PSMA-positive gallium-68 (68Ga)-labeled PSMA-11 positron-emission tomographic-computed tomographic scans. Patients were randomly assigned in a 2:1 ratio to receive either 177Lu-PSMA-617 (7.4 GBq every 6 weeks for four to six cycles) plus protocol-permitted standard care or standard care alone. Protocol-permitted standard care excluded chemotherapy, immunotherapy, radium-223 (223Ra), and investigational drugs. The alternate primary end points were imaging-based progression-free survival and overall survival, which were powered for hazard ratios of 0.67 and 0.73, respectively. Key secondary end points were objective response, disease control, and time to symptomatic skeletal events. Adverse events during treatment were those occurring no more than 30 days after the last dose and before subsequent anticancer treatment. RESULTS: From June 2018 to mid-October 2019, a total of 831 of 1179 screened patients underwent randomization. The baseline characteristics of the patients were balanced between the groups. The median follow-up was 20.9 months. 177Lu-PSMA-617 plus standard care significantly prolonged, as compared with standard care, both imaging-based progression-free survival (median, 8.7 vs. 3.4 months; hazard ratio for progression or death, 0.40; 99.2% confidence interval [CI], 0.29 to 0.57; P<0.001) and overall survival (median, 15.3 vs. 11.3 months; hazard ratio for death, 0.62; 95% CI, 0.52 to 0.74; P<0.001). All the key secondary end points significantly favored 177Lu-PSMA-617. The incidence of adverse events of grade 3 or above was higher with 177Lu-PSMA-617 than without (52.7% vs. 38.0%), but quality of life was not adversely affected. CONCLUSIONS: Radioligand therapy with 177Lu-PSMA-617 prolonged imaging-based progression-free survival and overall survival when added to standard care in patients with advanced PSMA-positive metastatic castration-resistant prostate cancer. (Funded by Endocyte, a Novartis company; VISION ClinicalTrials.gov number, NCT03511664.).


Asunto(s)
Dipéptidos/uso terapéutico , Compuestos Heterocíclicos con 1 Anillo/uso terapéutico , Calicreínas/antagonistas & inhibidores , Lutecio/uso terapéutico , Antígeno Prostático Específico/antagonistas & inhibidores , Antígeno Prostático Específico/uso terapéutico , Neoplasias de la Próstata Resistentes a la Castración/radioterapia , Radioisótopos/uso terapéutico , Anciano , Anciano de 80 o más Años , Terapia Combinada , Humanos , Lutecio/efectos adversos , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Próstata/diagnóstico por imagen , Neoplasias de la Próstata Resistentes a la Castración/diagnóstico por imagen , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/mortalidad , Radioisótopos/efectos adversos , Análisis de Supervivencia
10.
Thorax ; 79(3): 236-244, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-37620048

RESUMEN

BACKGROUND: Guidelines recommend urgent chest X-ray for newly presenting dyspnoea or haemoptysis but there is little evidence about their implementation. METHODS: We analysed linked primary care and hospital imaging data for patients aged 30+ years newly presenting with dyspnoea or haemoptysis in primary care during April 2012 to March 2017. We examined guideline-concordant management, defined as General Practitioner-ordered chest X-ray/CT carried out within 2 weeks of symptomatic presentation, and variation by sociodemographic characteristic and relevant medical history using logistic regression. Additionally, among patients diagnosed with cancer we described time to diagnosis, diagnostic route and stage at diagnosis by guideline-concordant status. RESULTS: In total, 22 560/162 161 (13.9%) patients with dyspnoea and 4022/8120 (49.5%) patients with haemoptysis received guideline-concordant imaging within the recommended 2-week period. Patients with recent chest imaging pre-presentation were much less likely to receive imaging (adjusted OR 0.16, 95% CI 0.14-0.18 for dyspnoea, and adjusted OR 0.09, 95% CI 0.06-0.11 for haemoptysis). History of chronic obstructive pulmonary disease/asthma was also associated with lower odds of guideline concordance (dyspnoea: OR 0.234, 95% CI 0.225-0.242 and haemoptysis: 0.88, 0.79-0.97). Guideline-concordant imaging was lower among dyspnoea presenters with prior heart failure; current or ex-smokers; and those in more socioeconomically disadvantaged groups.The likelihood of lung cancer diagnosis within 12 months was greater among the guideline-concordant imaging group (dyspnoea: 1.1% vs 0.6%; haemoptysis: 3.5% vs 2.7%). CONCLUSION: The likelihood of receiving urgent imaging concords with the risk of subsequent cancer diagnosis. Nevertheless, large proportions of dyspnoea and haemoptysis presenters do not receive prompt chest imaging despite being eligible, indicating opportunities for earlier lung cancer diagnosis.


Asunto(s)
Hemoptisis , Neoplasias Pulmonares , Humanos , Hemoptisis/diagnóstico por imagen , Hemoptisis/etiología , Estudios Retrospectivos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/diagnóstico por imagen , Disnea/diagnóstico por imagen , Disnea/etiología , Atención Primaria de Salud
11.
BMC Med ; 22(1): 82, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38424555

RESUMEN

BACKGROUND: Black men have higher prostate-specific antigen (PSA) levels and higher prostate cancer incidence and mortality than White men, while Asian men tend to have lower prostate cancer incidence and mortality than White men. Much of the evidence comes from the USA, and information from UK populations is limited. METHODS: This retrospective cohort study used data on patients registered at general practices in England contributing to the Clinical Practice Research Datalink (CPRD) Aurum dataset. Those eligible were men aged 40 and over with a record of ethnicity and a PSA test result recorded between 2010 and 2017 with no prior cancer diagnosis. The aim was to assess the incidence of prostate cancer following a raised PSA test result in men from different ethnic groups. Additionally, incidence of advanced prostate cancer was investigated. Cancer incidence was estimated from multi-level logistic regression models adjusting for potential confounding factors. RESULTS: 730,515 men with a PSA test were included (88.9% White). Black men and men with mixed ethnicity had higher PSA values, particularly for those aged above 60 years. In the year following a raised PSA result (using age-specific thresholds), Black men had the highest prostate cancer incidence at 24.7% (95% CI 23.3%, 26.2%); Asian men had the lowest at 13.4% (12.2%, 14.7%); incidence for White men was 19.8% (19.4%, 20.2%). The peak incidence of prostate cancer for all groups was in men aged 70-79. Incidence of prostate cancer diagnosed at an advanced stage was similar between Black and White men. CONCLUSIONS: More prostate cancer was diagnosed in Black men with a raised PSA result, but rates of advanced prostate cancer were not higher in this group. In this large primary care-based cohort, the incidence of prostate cancer in men with elevated PSA levels increases with increasing age, even when using age-adjusted thresholds, with Black men significantly more likely to be diagnosed compared to White or Asian men. The incidence of advanced stage prostate cancer at diagnosis was similar for Black and White men with a raised PSA result, but lower for Asian men.


Asunto(s)
Antígeno Prostático Específico , Neoplasias de la Próstata , Masculino , Humanos , Adulto , Persona de Mediana Edad , Estudios de Cohortes , Etnicidad , Estudios Retrospectivos , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/epidemiología , Atención Primaria de Salud , Reino Unido/epidemiología , Blanco
12.
New Phytol ; 243(5): 1698-1710, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38953386

RESUMEN

C4 photosynthesis is a complex trait requiring multiple developmental and metabolic alterations. Despite this complexity, it has independently evolved over 60 times. However, our understanding of the transition to C4 is complicated by the fact that variation in photosynthetic type is usually segregated between species that diverged a long time ago. Here, we perform a genome-wide association study (GWAS) using the grass Alloteropsis semialata, the only known species to have C3, intermediate, and C4 accessions that recently diverged. We aimed to identify genomic regions associated with the strength of the C4 cycle (measured using δ13C), and the development of C4 leaf anatomy. Genomic regions correlated with δ13C include regulators of C4 decarboxylation enzymes (RIPK), nonphotochemical quenching (SOQ1), and the development of Kranz anatomy (SCARECROW-LIKE). Regions associated with the development of C4 leaf anatomy in the intermediate individuals contain additional leaf anatomy regulators, including those responsible for vein patterning (GSL8) and meristem determinacy (GIF1). The parallel recruitment of paralogous leaf anatomy regulators between A. semialata and other C4 lineages implies the co-option of these genes is context-dependent, which likely has implications for the engineering of the C4 trait into C3 species.


Asunto(s)
Genoma de Planta , Estudio de Asociación del Genoma Completo , Fotosíntesis , Hojas de la Planta , Fotosíntesis/genética , Hojas de la Planta/anatomía & histología , Hojas de la Planta/genética , Poaceae/genética , Poaceae/anatomía & histología , Poaceae/fisiología , Isótopos de Carbono
13.
New Phytol ; 242(2): 774-785, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38389217

RESUMEN

C4 photosynthesis is a key innovation in land plant evolution, but its immediate effects on population demography are unclear. We explore the early impact of the C4 trait on the trajectories of C4 and non-C4 populations of the grass Alloteropsis semialata. We combine niche models projected into paleoclimate layers for the last 5 million years with demographic models based on genomic data. The initial split between C4 and non-C4 populations was followed by a larger expansion of the ancestral C4 population, and further diversification led to the unparalleled expansion of descendant C4 populations. Overall, C4 populations spread over three continents and achieved the highest population growth, in agreement with a broader climatic niche that rendered a large potential range over time. The C4 populations that remained in the region of origin, however, experienced lower population growth, rather consistent with local geographic constraints. Moreover, the posterior transfer of some C4-related characters to non-C4 counterparts might have facilitated the recent expansion of non-C4 populations in the region of origin. Altogether, our findings support that C4 photosynthesis provided an immediate demographic advantage to A. semialata populations, but its effect might be masked by geographic contingencies.


Asunto(s)
Fotosíntesis , Poaceae , Poaceae/genética , Fenotipo , Demografía
14.
BJU Int ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38961717

RESUMEN

OBJECTIVES: To assess the risk of venous thromboembolic events (VTEs) and bleeding with or without thromboprophylaxis during neoadjuvant chemotherapy in bladder cancer patients scheduled for radical cystectomy. MATERIALS AND METHODS: We conducted a retrospective cohort study in 4886 patients with non-metastatic bladder cancer undergoing cystectomy across 28 centres in 13 countries between 1990 and 2021. Inverse probability weighting analyses were performed to estimate the effect of thromboprophylaxis on VTE and bleeding. RESULTS: In 147 patients (3%) VTEs were recorded within the first year. These occurred a median (interquartile range [IQR]) of 127 (82-198) days after bladder cancer diagnosis. Bleeding events occurred in 131 patients (3%) within the first year. These occurred a median (IQR) of 101 (83-171) days after cancer diagnosis. In inverse probability weighting analyses, compared to patients without thromboprophylaxis during chemotherapy, patients with thromboprophylaxis had not only a lower risk of VTE (hazard ratio [HR] 0.32, 95% confidence interval [CI] 0.12-0.81; P = 0.016) but also a lower bleeding risk (HR 0.03, 95% CI 0.09-0.12; P <0.0001). The retrospective nature of the study was its main limitation. CONCLUSIONS: In this retrospective analysis, the benefit of thromboprophylaxis during neoadjuvant chemotherapy before cystectomy is in line with data from randomised trials in other malignancies. Our data suggest thromboprophylaxis is protective against VTEs and should be the standard of care during neoadjuvant chemotherapy.

15.
Am J Bot ; 111(2): e16280, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38334273

RESUMEN

PREMISE: Cultivation and naturalization of plants beyond their natural range can bring previously geographically isolated taxa together, increasing the opportunity for hybridization, the outcomes of which are not predictable. Here, we explored the phenotypic and genomic effects of interspecific gene flow following the widespread cultivation of Mentha spicata (spearmint), M. longifolia, and M. suaveolens. METHODS: We morphologically evaluated 155 herbarium specimens of three Mentha species and sequenced the genomes of a subset of 93 specimens. We analyzed the whole genomes in a population and the phylogenetic framework and associated genomic classifications in conjunction with the morphological assessments. RESULTS: The allopolyploid M. spicata, which likely evolved in cultivation, had altered trichome characters, that is possibly a product of human selection for a more palatable plant or a byproduct of selection for essential oils. There were signs of genetic admixture between mints, including allopolyploids, indicating that the reproductive barriers between Mentha species with differences in ploidy are likely incomplete. Still, despite gene flow between species, we found that genetic variants associated with the cultivated trichome morphology continue to segregate. CONCLUSIONS: Although hybridization, allopolyploidization, and human selection during cultivation can increase species richness (e.g., by forming hybrid taxa), we showed that unless reproductive barriers are strong, these processes can also result in mixing of genes between species and the potential loss of natural biodiversity.


Asunto(s)
Mentha , Aceites Volátiles , Humanos , Mentha/genética , Flujo Génico , Filogenia , Aceites Volátiles/farmacología , Hibridación Genética
16.
BMC Med Res Methodol ; 24(1): 73, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38515018

RESUMEN

BACKGROUND: Misclassification bias (MB) is the deviation of measured from true values due to incorrect case assignment. This study compared MB when cystectomy status was determined using administrative database codes vs. predicted cystectomy probability. METHODS: We identified every primary cystectomy-diversion type at a single hospital 2009-2019. We linked to claims data to measure true association of cystectomy with 30 patient and hospitalization factors. Associations were also measured when cystectomy status was assigned using billing codes and by cystectomy probability from multivariate logistic regression model with covariates from administrative data. MB was the difference between measured and true associations. RESULTS: 500 people underwent cystectomy (0.12% of 428 677 hospitalizations). Sensitivity and positive predictive values for cystectomy codes were 97.1% and 58.6% for incontinent diversions and 100.0% and 48.4% for continent diversions, respectively. The model accurately predicted cystectomy-incontinent diversion (c-statistic [C] 0.999, Integrated Calibration Index [ICI] 0.000) and cystectomy-continent diversion (C:1.000, ICI 0.000) probabilities. MB was significantly lower when model-based predictions was used to impute cystectomy-diversion type status using for both incontinent cystectomy (F = 12.75; p < .0001) and continent cystectomy (F = 11.25; p < .0001). CONCLUSIONS: A model using administrative data accurately returned the probability that cystectomy by diversion type occurred during a hospitalization. Using this model to impute cystectomy status minimized MB. Accuracy of administrative database research can be increased by using probabilistic imputation to determine case status instead of individual codes.


Asunto(s)
Cistectomía , Neoplasias de la Vejiga Urinaria , Humanos , Hospitalización , Probabilidad , Sesgo , Bases de Datos Factuales , Neoplasias de la Vejiga Urinaria/cirugía
17.
Inorg Chem ; 63(11): 4982-4988, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38452752

RESUMEN

During our group's continued exploration of group 14 chalcogenides, we discovered two new compounds, Sr8Ge4Se17 and Ba8Sn4Se17. Both compounds have an 8:4:17 stoichiometric ratio but adopt different centrosymmetric crystal structures. Sr8Ge4Se17 crystallizes in the triclinic P1̅ space group with a = 11.8429(18) Å, b = 12.172(3) Å, c = 13.624(3) Å, α = 114.472(5)0, ß = 97.396(5)0, γ = 107.040(5)0, and Z = 2. Ba8Sn4Se17 crystallizes in the monoclinic C2/c space group with a = 47.286(3) Å, b = 12.6294(5) Å, c = 25.7303(15) Å, ß = 104.585(5)0, and Z = 16. The unit cell of Ba8Sn4Se17 is approximately eight times larger than the unit cell of Sr8Ge4Se17, which is a consequence of the differently aligned tetrahedra, resulting in a quadrupled a axis, unchanged b axis, and doubled c axis. The lattice parameters and atomic coordinates were finalized via Rietveld refinements on data collected at a high-energy synchrotron beamline. Both compounds are semiconductors with band gaps in the visible region. Sr8Ge4Se17 and Ba8Sn4Se17 have optical band gaps of 1.88 and 1.93 eV, respectively. Both compounds have remarkably low thermal conductivities owing to their low symmetries and large unit cells. The minimum experimental thermal conductivity values of Sr8Ge4Se17 and Ba8Sn4Se17 are 0.45 W m-1 K-1 at 321 K and 0.31 W m-1 K-1 at 324 K, respectively.

18.
Inorg Chem ; 63(19): 8531-8536, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38695157

RESUMEN

Crystalline ceramics are candidate materials for the immobilization of radionuclides, particularly transuranics (such as U, Pu, and Am), arising from the nuclear fuel cycle. Due to the α-decay of transuranics and the associated recoil of the parent nucleus, crystalline materials may eventually be rendered amorphous through changes to the crystal lattice caused by these recoil events. Previous work has shown irradiation of titanate-based ceramics to change the local cation environment significantly, particularly in the case of Ti which was shown to change from 6- to 5-fold coordination. Here, this work expands the Ti-based study to investigate the behavior in Fe-based materials, using LaFeO3 as an example material. Irradiation was simulated by heavy ion implantation of the bulk LaFeO3 ceramic, with the resulting amorphous layer characterized with grazing angle X-ray absorption spectroscopy (GA-XAS). Insights into the Fe speciation changes exhibited by the amorphized surface layer were provided through quantitative analysis, including pre-edge analysis, and modeling of the extended X-ray absorption fine structure (EXAFS), of the GA-XAS data.

19.
Conserv Biol ; 38(1): e14065, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36811200

RESUMEN

A range of conservation and restoration tools are needed to safeguard the structure and function of aquatic ecosystems. Aquaculture, the culturing of aquatic organisms, often contributes to the numerous stressors that aquatic ecosystems face, yet some aquaculture activities can also deliver ecological benefits. We reviewed the literature on aquaculture activities that may contribute to conservation and restoration outcomes, either by enhancing the persistence or recovery of one or more target species or by moving aquatic ecosystems toward a target state. We identified 12 ecologically beneficial outcomes achievable via aquaculture: species recovery, habitat restoration, habitat rehabilitation, habitat protection, bioremediation, assisted evolution, climate change mitigation, wild harvest replacement, coastal defense, removal of overabundant species, biological control, and ex situ conservation. This list may be expanded as new applications are discovered. Positive intentions do not guarantee positive ecological outcomes, so it is critical that potentially ecologically beneficial aquaculture activities be evaluated via clear and measurable indicators of success to reduce potential abuse by greenwashing. Unanimity on outcomes, indicators, and related terminology will bring the field of aquaculture-environment interactions into line with consensus standards in conservation and restoration ecology. Broad consensus will also aid the development of future certification schemes for ecologically beneficial aquaculture.


Se necesita una gama de herramientas de conservación y restauración para salvaguardar la estructura y función de los ecosistemas acuáticos. La acuacultura (el cultivo de organismos acuáticos) generalmente contribuye a los numerosos estresantes que soportan los ecosistemas acuáticos, aunque algunas actividades de la acuacultura también pueden proporcionar beneficios ecológicos. Revisamos la literatura sobre las actividades de acuacultura que pueden contribuir a los resultados de conservación y restauración, ya sea al incrementar la persistencia o recuperación de una o más especies objetivo o al llevar a los ecosistemas acuáticos hacia un estado objetivo. Identificamos doce resultados con beneficios ecológicos que pueden lograrse con la acuacultura: recuperación de la especie, recuperación del hábitat, restauración del hábitat, rehabilitación del hábitat, protección del hábitat, bioreparación, evolución asistida, mitigación del cambio climático, sustitución de la captura silvestre, defensa costera, eliminación de las especies sobreabundantes, control biológico y conservación ex situ. Esta lista puede expandirse conforme se descubren nuevas aplicaciones. Las intenciones positivas no garantizan resultados ecológicos positivos, así que es importante que se evalúen las actividades de acuacultura con un posible beneficio ecológico por medio de indicadores del éxito claros y medibles para reducir el abuso potencial por ecoblanqueo o greenwashing. La unanimidad en los resultados, indicadores y terminología relacionada armonizará las interacciones entre la acuacultura y el ambiente con los estándares de la conservación y la ecología de la restauración. Un consenso generalizado también ayudará con el desarrollo de futuros esquemas de certificación para la acuacultura con beneficios ecológicos. Obtención de resultados de conservación y restauración a través de la acuacultura con beneficios ecológicos.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Cambio Climático , Acuicultura
20.
Br J Anaesth ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39232909

RESUMEN

BACKGROUND: Frailty is associated with morbidity and mortality after surgery. The association of frailty with decisional regret is poorly defined. Our objective was to estimate the association of preoperative frailty with decisional regret status in the year after surgery. METHODS: We conducted a secondary analysis of a prospective, multicentre cohort study of patients aged ≥65 years who underwent elective noncardiac surgery. Decisional regret about having undergone surgery was ascertained at 30, 90, and 365 (primary time point) days after surgery using a 3-point ordinal scale. Bayesian ordinal logistic regression was used to estimate the association of frailty with decisional regret, adjusted for surgery type, age, sex, and mental health conditions. Subgroup and sensitivity analyses were conducted. RESULTS: We identified 669 patients; 293 (43.8%) lived with frailty. At 365 days after surgery, the unadjusted odds ratio (OR) associating frailty with greater decisional regret was 2.21 (95% credible interval [CrI] 0.98-5.09; P(OR>1)=0.97), which was attenuated after confounder adjustment (adjusted OR 1.68, 95% CrI 0.84-3.36; P(OR>1)=0.93). Similar results were estimated at 30 and 90 days. Additional adjustment for baseline comorbidities and disability score substantially altered the OR at 365 days (0.89, 95% CrI 0.37-2.12; P(OR>1)=0.39). There was a high probability that surgery type was an effect modifier (non-orthopaedic: OR 1.90, 95% CrI 1.00-3.59; P(OR>1)=0.98); orthopaedic: OR 0.87, 95% CrI 0.41-1.91; P(OR>1)=0.36). CONCLUSIONS: Among older surgical patients, there appears to be a complex association with frailty and decisional regret, with substantial heterogeneity based on assumed causal pathways and surgery type. Future studies are required to untangle the complex interplay between these factors.

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