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1.
Immunity ; 54(8): 1758-1771.e7, 2021 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-34256013

RESUMEN

Apoptosis can potently defend against intracellular pathogens by directly killing microbes and eliminating their replicative niche. However, the reported ability of Mycobacterium tuberculosis to restrict apoptotic pathways in macrophages in vitro has led to apoptosis being dismissed as a host-protective process in tuberculosis despite a lack of in vivo evidence. Here we define crucial in vivo functions of the death receptor-mediated and BCL-2-regulated apoptosis pathways in mediating protection against tuberculosis by eliminating distinct populations of infected macrophages and neutrophils and priming T cell responses. We further show that apoptotic pathways can be targeted therapeutically with clinical-stage compounds that antagonize inhibitor of apoptosis (IAP) proteins to promote clearance of M. tuberculosis in mice. These findings reveal that any inhibition of apoptosis by M. tuberculosis is incomplete in vivo, advancing our understanding of host-protective responses to tuberculosis (TB) and revealing host pathways that may be targetable for treatment of disease.


Asunto(s)
Apoptosis/inmunología , Macrófagos/inmunología , Mycobacterium tuberculosis/inmunología , Neutrófilos/inmunología , Tuberculosis Pulmonar/inmunología , Animales , Caspasa 8/genética , Caspasa 8/metabolismo , Línea Celular , Dipéptidos/uso terapéutico , Humanos , Indoles/uso terapéutico , Activación de Linfocitos/inmunología , Macrófagos/microbiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neutrófilos/microbiología , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Linfocitos T/inmunología , Tiazoles/uso terapéutico , Tuberculosis Pulmonar/tratamiento farmacológico
2.
Nature ; 586(7828): 317-321, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32640464

RESUMEN

Acetohydroxyacid synthase (AHAS), also known as acetolactate synthase, is a flavin adenine dinucleotide-, thiamine diphosphate- and magnesium-dependent enzyme that catalyses the first step in the biosynthesis of branched-chain amino acids1. It is the target for more than 50 commercial herbicides2. AHAS requires both catalytic and regulatory subunits for maximal activity and functionality. Here we describe structures of the hexadecameric AHAS complexes of Saccharomyces cerevisiae and dodecameric AHAS complexes of Arabidopsis thaliana. We found that the regulatory subunits of these AHAS complexes form a core to which the catalytic subunit dimers are attached, adopting the shape of a Maltese cross. The structures show how the catalytic and regulatory subunits communicate with each other to provide a pathway for activation and for feedback inhibition by branched-chain amino acids. We also show that the AHAS complex of Mycobacterium tuberculosis adopts a similar structure, thus demonstrating that the overall AHAS architecture is conserved across kingdoms.


Asunto(s)
Acetolactato Sintasa/química , Arabidopsis/enzimología , Saccharomyces cerevisiae/enzimología , Acetolactato Sintasa/metabolismo , Adenosina Trifosfato/metabolismo , Aminoácidos de Cadena Ramificada/biosíntesis , Dominio Catalítico , Activación Enzimática , Evolución Molecular , Retroalimentación Fisiológica , Modelos Moleculares , Complejos Multiproteicos/química , Complejos Multiproteicos/metabolismo , Mycobacterium tuberculosis/enzimología , Unión Proteica , Conformación Proteica , Subunidades de Proteína/química , Subunidades de Proteína/metabolismo , Valina/metabolismo
3.
Artículo en Inglés | MEDLINE | ID: mdl-38568479

RESUMEN

RATIONALE: Idiopathic Pulmonary Arterial Hypertension (IPAH) is characterized by extensive pulmonary vascular remodeling due to plexiform and obliterative lesions, media hypertrophy, inflammatory cell infiltration, and alterations of the adventitia. OBJECTIVE: Test the hypothesis that microscopic IPAH vascular lesions express unique molecular profiles, which collectively are different from control pulmonary arteries. METHODS: We used digital spatial transcriptomics to profile the genome-wide differential transcriptomic signature of key pathological lesions (plexiform, obliterative, intima+media hypertrophy, and adventitia) in IPAH lungs (n= 11) and compared these data to the intima+media and adventitia of control pulmonary artery (n=5). RESULTS: We detected 8273 transcripts in the IPAH lesions and control lung pulmonary arteries. Plexiform lesions and IPAH adventitia exhibited the greatest number of differentially expressed genes when compared with intima-media hypertrophy and obliterative lesions. Plexiform lesions in IPAH showed enrichment for (i) genes associated with TGFß-signaling and (ii) mutated genes affecting the extracellular matrix and endothelial-mesenchymal transformation. Plexiform lesions and IPAH adventitia showed upregulation of genes involved in immune and interferon signaling, coagulation, and complement pathways. Cellular deconvolution indicated variability in the number of vascular and inflammatory cells between IPAH lesions, which underlies the differential transcript profiling. CONCLUSIONS: IPAH lesions express unique molecular transcript profiles enriched for pathways involving pathogenetic pathways, including genetic disease drivers, innate and acquired immunity, hypoxia sensing, and angiogenesis signaling. These data provide a rich molecular-structural framework in IPAH vascular lesions that inform novel biomarkers and therapeutic targets in this highly morbid disease.

4.
PLoS Pathog ; 18(2): e1010185, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35143591

RESUMEN

Arthritogenic alphaviruses are mosquito-borne viruses that are a major cause of infectious arthropathies worldwide, and recent outbreaks of chikungunya virus and Ross River virus (RRV) infections highlight the need for robust intervention strategies. Alphaviral arthritis can persist for months after the initial acute disease, and is mediated by cellular immune responses. A common strategy to limit inflammation and pathology is to dampen the overwhelming inflammatory responses by modulating proinflammatory cytokine pathways. Here, we investigate the contribution of interleukin-17 (IL-17), a cytokine involved in arthropathies such as rheumatoid arthritis, in the development RRV-induced arthritis and myositis. IL-17 was quantified in serum from RRV-infected patients, and mice were infected with RRV and joints and muscle tissues collected to analyse cellular infiltrates, tissue mRNA, cytokine expression, and joint and muscle histopathology. IL-17 expression was increased in musculoskeletal tissues and serum of RRV-infected mice and humans, respectively. IL-17-producing T cells and neutrophils contributed to the cellular infiltrate in the joint and muscle tissue during acute RRV disease in mice. Blockade of IL-17A/F using a monoclonal antibody (mAb) reduced disease severity in RRV-infected mice and led to decreased proinflammatory proteins, cellular infiltration in synovial tissues and cartilage damage, without affecting viral titers in inflamed tissues. IL-17A/F blockade triggered a shift in transcriptional profile of both leukocyte infiltrates and musculoskeletal stromal cells by downregulating proinflammatory genes. This study highlights a previously uncharacterized role for an effector cytokine in alphaviral pathology and points towards potential therapeutic benefit in targeting IL-17 to treat patients presenting with RRV-induced arthropathy.


Asunto(s)
Artritis Reumatoide/inmunología , Inmunidad Celular , Inflamación/inmunología , Interleucina-17/inmunología , Miositis/inmunología , Virus del Río Ross/inmunología , Infecciones por Alphavirus/inmunología , Infecciones por Alphavirus/virología , Animales , Artritis Reumatoide/virología , Chlorocebus aethiops , Citocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Miositis/virología , Células Vero , Carga Viral
5.
Histopathology ; 84(7): 1139-1153, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38409878

RESUMEN

BACKGROUND: Artificial intelligence (AI) has numerous applications in pathology, supporting diagnosis and prognostication in cancer. However, most AI models are trained on highly selected data, typically one tissue slide per patient. In reality, especially for large surgical resection specimens, dozens of slides can be available for each patient. Manually sorting and labelling whole-slide images (WSIs) is a very time-consuming process, hindering the direct application of AI on the collected tissue samples from large cohorts. In this study we addressed this issue by developing a deep-learning (DL)-based method for automatic curation of large pathology datasets with several slides per patient. METHODS: We collected multiple large multicentric datasets of colorectal cancer histopathological slides from the United Kingdom (FOXTROT, N = 21,384 slides; CR07, N = 7985 slides) and Germany (DACHS, N = 3606 slides). These datasets contained multiple types of tissue slides, including bowel resection specimens, endoscopic biopsies, lymph node resections, immunohistochemistry-stained slides, and tissue microarrays. We developed, trained, and tested a deep convolutional neural network model to predict the type of slide from the slide overview (thumbnail) image. The primary statistical endpoint was the macro-averaged area under the receiver operating curve (AUROCs) for detection of the type of slide. RESULTS: In the primary dataset (FOXTROT), with an AUROC of 0.995 [95% confidence interval [CI]: 0.994-0.996] the algorithm achieved a high classification performance and was able to accurately predict the type of slide from the thumbnail image alone. In the two external test cohorts (CR07, DACHS) AUROCs of 0.982 [95% CI: 0.979-0.985] and 0.875 [95% CI: 0.864-0.887] were observed, which indicates the generalizability of the trained model on unseen datasets. With a confidence threshold of 0.95, the model reached an accuracy of 94.6% (7331 classified cases) in CR07 and 85.1% (2752 classified cases) for the DACHS cohort. CONCLUSION: Our findings show that using the low-resolution thumbnail image is sufficient to accurately classify the type of slide in digital pathology. This can support researchers to make the vast resource of existing pathology archives accessible to modern AI models with only minimal manual annotations.


Asunto(s)
Neoplasias Colorrectales , Aprendizaje Profundo , Humanos , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/diagnóstico , Redes Neurales de la Computación , Procesamiento de Imagen Asistido por Computador/métodos , Interpretación de Imagen Asistida por Computador/métodos
6.
J Org Chem ; 89(1): 798-803, 2024 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-38131648

RESUMEN

The unusual and sterically constrained amino acid, seco-1-azacubane-2-carboxylic acid, was incorporated into a range of bioactive chemical templates, including enalaprilat, perindoprilat, endomorphin-2 and isoniazid, and subjected to biological testing. The endomorphin-2 derivative displayed increased activity at the δ opioid receptor, but a loss in activity was observed in the other cases, although human normal cell line evaluation suggests limited cytotoxic effects.


Asunto(s)
Ácidos Carboxílicos , Receptores Opioides mu , Humanos , Receptores Opioides mu/química , Receptores Opioides mu/metabolismo , Aminoácidos , Línea Celular
7.
Eur J Appl Physiol ; 2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38613679

RESUMEN

PURPOSE: Uncertainty exists if post-resistance exercise hydrotherapy attenuates chronic inflammatory and hormone responses. The effects of repeated post-resistance exercise water immersion on inflammatory and hormone responses in athletes were investigated. METHODS: Male, academy Super Rugby players (n = 18, 19.9 ± 1.5 y, 1.85 ± 0.06 m, 98.3 ± 10.7 kg) participated in a 12-week programme divided into 3 × 4-week blocks of post-resistance exercise water immersion (either, no immersion control [CON]; cold [CWI]; or hot [HWI] water immersion), utilising a randomised cross-over pre-post design. Fasted, morning blood measures were collected prior to commencement of first intervention block, and every fourth week thereafter. Linear mixed-effects models were used to analyse main (treatment, time) and interaction effects. RESULTS: Repeated CWI (p = 0.025, g = 0.05) and HWI (p < 0.001, g = 0.62) reduced creatine kinase (CK), compared to CON. HWI decreased (p = 0.013, g = 0.59) interleukin (IL)-1ra, compared to CON. HWI increased (p < 0.001-0.026, g = 0.06-0.17) growth factors (PDGF-BB, IGF-1), compared to CON and CWI. CWI increased (p = 0.004, g = 0.46) heat shock protein-72 (HSP-72), compared to HWI. CONCLUSION: Post-resistance exercise CWI or HWI resulted in trivial and moderate reductions in CK, respectively, which may be partly due to hydrostatic effects of water immersion. Post-resistance exercise HWI moderately decreased IL-1ra, which may be associated with post-resistance exercise skeletal muscle inflammation influencing chronic resistance exercise adaptive responses. Following post-resistance exercise water immersion, CWI increased HSP-72 suggesting a thermoregulatory response indicating improved adaptive inflammatory responses to temperature changes, while HWI increased growth factors (PDGF-BB, IGF-1) indicating different systematic signalling pathway activation. Our data supports the continued use of post-resistance exercise water immersion recovery strategies of any temperature during in-season competition phases for improved inflammatory adaptive responses in athletes.

8.
Mol Microbiol ; 117(5): 973-985, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35338720

RESUMEN

Intracellular bacterial pathogens such as Mycobacterium tuberculosis are remarkably adept at surviving within a host, employing a variety of mechanisms to counteract host defenses and establish a protected niche. Constant surveying of the environment is key for pathogenic mycobacteria to discern their immediate location and coordinate the expression of genes necessary for adaptation. Two-component systems efficiently perform this role, typically comprised of a transmembrane sensor kinase and a cytoplasmic response regulator. In this review, we describe the role of two-component systems in bacterial pathogenesis, focusing predominantly on the role of sensor kinases of M. tuberculosis. We highlight important features of sensor kinases in mycobacterial infection, discuss ways in which these signaling proteins sense and respond to environments, and how this is attuned to their intracellular lifestyle. Finally, we discuss recent studies which have identified and characterized inhibitors of two-component sensor kinases toward establishing a new strategy in anti-mycobacterial therapy.


Asunto(s)
Infecciones por Mycobacterium , Mycobacterium tuberculosis , Adaptación Fisiológica , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Histidina/metabolismo , Histidina Quinasa/genética , Histidina Quinasa/metabolismo , Humanos , Mycobacterium tuberculosis/metabolismo
9.
Clin Immunol ; 246: 109209, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36539107

RESUMEN

Children infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) develop less severe coronavirus disease 2019 (COVID-19) than adults. The mechanisms for the age-specific differences and the implications for infection-induced immunity are beginning to be uncovered. We show by longitudinal multimodal analysis that SARS-CoV-2 leaves a small footprint in the circulating T cell compartment in children with mild/asymptomatic COVID-19 compared to adult household contacts with the same disease severity who had more evidence of systemic T cell interferon activation, cytotoxicity and exhaustion. Children harbored diverse polyclonal SARS-CoV-2-specific naïve T cells whereas adults harbored clonally expanded SARS-CoV-2-specific memory T cells. A novel population of naïve interferon-activated T cells is expanded in acute COVID-19 and is recruited into the memory compartment during convalescence in adults but not children. This was associated with the development of robust CD4+ memory T cell responses in adults but not children. These data suggest that rapid clearance of SARS-CoV-2 in children may compromise their cellular immunity and ability to resist reinfection.


Asunto(s)
COVID-19 , Humanos , Adulto , SARS-CoV-2 , Linfocitos T CD4-Positivos , Inmunidad Celular , Activación de Linfocitos , Anticuerpos Antivirales
10.
Immunol Cell Biol ; 101(10): 916-920, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37885423

RESUMEN

Allan Cripps was internationally recognized in the field of mucosal immunology, in particular the relationship between respiratory diseases and mucosal immunization strategies. Allan's career spanned scientific and applied research, commercialization, health education, and evolved into leadership roles in public-health and academic administration. Allan published over 400 papers and mentored over 40 research higher degree candidates. Allan was renowned for his mentorship, that did not end with the awarding of a PhD or Master's degree, but continued across a lifetime of professional engagement. Allan's key contributions to immunology included characterizing the ontogeny of the human mucosal immune system, understanding the impact of respiratory infections and otitis media in children, developing diagnostic technologies and mucosal vaccine strategies, and identifying the roles of the common mucosal immune system in human health. In this biography for the 100th anniversary of the Journal, we follow his journey of discovery and contributions to immunological research.


Asunto(s)
Infecciones del Sistema Respiratorio , Vacunas , Niño , Humanos , Inmunización , Mentores , Vacunación
11.
J Virol ; 96(17): e0099922, 2022 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-36000846

RESUMEN

Arthritogenic alphaviruses are mosquito-borne arboviruses that include several re-emerging human pathogens, including the chikungunya (CHIKV), Ross River (RRV), Mayaro (MAYV), and o'nyong-nyong (ONNV) virus. Arboviruses are transmitted via a mosquito bite to the skin. Herein, we describe intradermal RRV infection in a mouse model that replicates the arthritis and myositis seen in humans with Ross River virus disease (RRVD). We show that skin infection with RRV results in the recruitment of inflammatory monocytes and neutrophils, which together with dendritic cells migrate to draining lymph nodes (LN) of the skin. Neutrophils and monocytes are productively infected and traffic virus from the skin to LN. We show that viral envelope N-linked glycosylation is a key determinant of skin immune responses and disease severity. RRV grown in mammalian cells elicited robust early antiviral responses in the skin, while RRV grown in mosquito cells stimulated poorer early antiviral responses. We used glycan mass spectrometry to characterize the glycan profile of mosquito and mammalian cell-derived RRV, showing deglycosylation of the RRV E2 glycoprotein is associated with curtailed skin immune responses and reduced disease following intradermal infection. Altogether, our findings demonstrate skin infection with an arthritogenic alphavirus leads to musculoskeletal disease and envelope glycoprotein glycosylation shapes disease outcome. IMPORTANCE Arthritogenic alphaviruses are transmitted via mosquito bites through the skin, potentially causing debilitating diseases. Our understanding of how viral infection starts in the skin and how virus systemically disseminates to cause disease remains limited. Intradermal arbovirus infection described herein results in musculoskeletal pathology, which is dependent on viral envelope N-linked glycosylation. As such, intradermal infection route provides new insights into how arboviruses cause disease and could be extended to future investigations of skin immune responses following infection with other re-emerging arboviruses.


Asunto(s)
Infecciones por Alphavirus , Artritis , Miositis , Polisacáridos , Virus del Río Ross , Piel , Infecciones por Alphavirus/complicaciones , Infecciones por Alphavirus/inmunología , Animales , Antivirales/inmunología , Artritis/complicaciones , Artritis/inmunología , Culicidae/virología , Células Dendríticas , Modelos Animales de Enfermedad , Glicosilación , Humanos , Espectrometría de Masas , Ratones , Monocitos , Miositis/complicaciones , Miositis/inmunología , Neutrófilos , Polisacáridos/química , Polisacáridos/inmunología , Virus del Río Ross/inmunología , Piel/inmunología , Piel/virología , Proteínas del Envoltorio Viral/química , Proteínas del Envoltorio Viral/inmunología
12.
Histopathology ; 83(1): 80-90, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36939589

RESUMEN

AIMS: Malignant polyps are examined to assess histological features which predict residual tumour in the unresected bowel and guide surgical decision-making. One of the most important of these features is resection margin involvement, although the best definition of margin involvement is unknown. In this study we aimed to investigate three different definitions and determine their impact on clinical outcomes. METHODS AND RESULTS: One hundred and sixty-five malignant polyps removed endoscopically were identified and histological features correlated with either residual tumour in subsequent surgical resections or tumour recurrence following a period of clinical follow-up. Involvement of the polyp margin by cancer was defined in three different ways and outcomes compared. Tumour recurrence was associated with tumour grade, mucinous histology and resection margin involvement. All three definitions of margin involvement separated polyps into clinically significant categories; however, a margin ≤ 1 mm identified 73% of polyps as 'high-risk' compared with 59.1% when involvement was defined as tumour within the zone of coagulation artefact at the polyp base or 50% when tumour was present at the margin. All three 'low-risk' groups had a locoregional recurrence rate < 6.5%. CONCLUSIONS: Definitions of margin involvement for endoscopically removed malignant polyps in the colon and rectum vary between health-care systems, but a 1-mm clearance is widely used in Europe and North America. Our results suggest that a 1-mm margin is unnecessary and should be replaced by a definition based on tumour at the margin or within coagulation artefact at the polyp base.


Asunto(s)
Pólipos del Colon , Humanos , Pólipos del Colon/cirugía , Pólipos del Colon/patología , Recurrencia Local de Neoplasia , Neoplasia Residual , Márgenes de Escisión , Endoscopía/métodos
13.
J Pathol ; 256(1): 50-60, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34561876

RESUMEN

Deep learning is a powerful tool in computational pathology: it can be used for tumor detection and for predicting genetic alterations based on histopathology images alone. Conventionally, tumor detection and prediction of genetic alterations are two separate workflows. Newer methods have combined them, but require complex, manually engineered computational pipelines, restricting reproducibility and robustness. To address these issues, we present a new method for simultaneous tumor detection and prediction of genetic alterations: The Slide-Level Assessment Model (SLAM) uses a single off-the-shelf neural network to predict molecular alterations directly from routine pathology slides without any manual annotations, improving upon previous methods by automatically excluding normal and non-informative tissue regions. SLAM requires only standard programming libraries and is conceptually simpler than previous approaches. We have extensively validated SLAM for clinically relevant tasks using two large multicentric cohorts of colorectal cancer patients, Darmkrebs: Chancen der Verhütung durch Screening (DACHS) from Germany and Yorkshire Cancer Research Bowel Cancer Improvement Programme (YCR-BCIP) from the UK. We show that SLAM yields reliable slide-level classification of tumor presence with an area under the receiver operating curve (AUROC) of 0.980 (confidence interval 0.975, 0.984; n = 2,297 tumor and n = 1,281 normal slides). In addition, SLAM can detect microsatellite instability (MSI)/mismatch repair deficiency (dMMR) or microsatellite stability/mismatch repair proficiency with an AUROC of 0.909 (0.888, 0.929; n = 2,039 patients) and BRAF mutational status with an AUROC of 0.821 (0.786, 0.852; n = 2,075 patients). The improvement with respect to previous methods was validated in a large external testing cohort in which MSI/dMMR status was detected with an AUROC of 0.900 (0.864, 0.931; n = 805 patients). In addition, SLAM provides human-interpretable visualization maps, enabling the analysis of multiplexed network predictions by human experts. In summary, SLAM is a new simple and powerful method for computational pathology that could be applied to multiple disease contexts. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.


Asunto(s)
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Inestabilidad de Microsatélites , Mutación/genética , Síndromes Neoplásicos Hereditarios/genética , Síndromes Neoplásicos Hereditarios/patología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Encefálicas/diagnóstico , Estudios de Cohortes , Neoplasias Colorrectales/diagnóstico , Aprendizaje Profundo , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Síndromes Neoplásicos Hereditarios/diagnóstico , Reproducibilidad de los Resultados
14.
J Pathol ; 256(3): 269-281, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34738636

RESUMEN

The spread of early-stage (T1 and T2) adenocarcinomas to locoregional lymph nodes is a key event in disease progression of colorectal cancer (CRC). The cellular mechanisms behind this event are not completely understood and existing predictive biomarkers are imperfect. Here, we used an end-to-end deep learning algorithm to identify risk factors for lymph node metastasis (LNM) status in digitized histopathology slides of the primary CRC and its surrounding tissue. In two large population-based cohorts, we show that this system can predict the presence of more than one LNM in pT2 CRC patients with an area under the receiver operating curve (AUROC) of 0.733 (0.67-0.758) and patients with any LNM with an AUROC of 0.711 (0.597-0.797). Similarly, in pT1 CRC patients, the presence of more than one LNM or any LNM was predictable with an AUROC of 0.733 (0.644-0.778) and 0.567 (0.542-0.597), respectively. Based on these findings, we used the deep learning system to guide human pathology experts towards highly predictive regions for LNM in the whole slide images. This hybrid human observer and deep learning approach identified inflamed adipose tissue as the highest predictive feature for LNM presence. Our study is a first proof of concept that artificial intelligence (AI) systems may be able to discover potentially new biological mechanisms in cancer progression. Our deep learning algorithm is publicly available and can be used for biomarker discovery in any disease setting. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Asunto(s)
Tejido Adiposo/patología , Neoplasias Colorrectales/patología , Aprendizaje Profundo , Diagnóstico por Computador , Detección Precoz del Cáncer , Interpretación de Imagen Asistida por Computador , Ganglios Linfáticos/patología , Microscopía , Biopsia , Humanos , Metástasis Linfática , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Prueba de Estudio Conceptual , Reproducibilidad de los Resultados , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo
15.
Colorectal Dis ; 25(3): 352-356, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36511125

RESUMEN

AIM: The international FOxTROT trial, recently published in the Journal of Clinical Oncology is the first randomized controlled trial testing neoadjuvant chemotherapy (NAC) with oxaliplatin and 5-fluorouracil in locally advanced, but operable, colon cancer. The trial met its primary endpoint with fewer patients experiencing recurrent or residual disease at 2 years with NAC compared with the control (16.8% vs. 21.2%, risk ratio = 0.74, p  = 0.042). Translating the findings of the FOxTROT trial into improved patient outcomes is dependent on implementation of new neoadjuvant chemotherapy (NAC) pathways in colorectal cancer. METHOD: We describe our experience implementing a novel neoadjuvant treatment pathway in colorectal cancer at a large UK teaching hospital. RESULTS: To date 64 patients have been commenced on the novel pathway following presentation and adoption of the FOxTROT trial results. We present key lessons and strategies developed across the multidisciplinary team to minimize impact on person hours, service capacity and budget, whilst building patient safety and confidence. CONCLUSION: Use of NAC for locally advanced colon cancer has been shown to improve surgical outcomes and longer term cancer outcomes. Provision of NAC requires some modifications to current treatment pathways but can be delivered with team working and without the requirement for additional resources.


Asunto(s)
Neoplasias del Colon , Terapia Neoadyuvante , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioterapia Adyuvante/métodos , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/cirugía , Neoplasias del Colon/patología , Fluorouracilo/uso terapéutico , Terapia Neoadyuvante/métodos , Estadificación de Neoplasias
16.
Eur J Appl Physiol ; 123(2): 351-359, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36284024

RESUMEN

PURPOSE: Following resistance exercise, uncertainty exists as to whether the regular application of cold water immersion attenuates lean muscle mass increases in athletes. The effects of repeated post-resistance exercise cold versus hot water immersion on body composition and neuromuscular jump performance responses in athletes were investigated. METHODS: Male, academy Super Rugby players (n = 18, 19.9 ± 1.5 y, 1.85 ± 0.06 m, 98.3 ± 10.7 kg) participated in a 12-week (4-week × 3-intervention, i.e., control [CON], cold [CWI] or hot [HWI] water immersion) resistance exercise programme, utilising a randomised cross-over pre-post-design. Body composition measures were collected using dual-energy X-ray absorptiometry prior to commencement and every fourth week thereafter. Neuromuscular squat (SJ) and counter-movement jump (CMJ) performance were measured weekly. Linear mixed-effects models were used to analyse main (treatment, time) and interaction effects. RESULTS: There were no changes in lean (p = 0.960) nor fat mass (p = 0.801) between interventions. CON (p = 0.004) and CWI (p = 0.003) increased (g = 0.08-0.19) SJ height, compared to HWI. There were no changes in CMJ height (p = 0.482) between interventions. CONCLUSION: Repeated post-resistance exercise whole-body CWI or HWI does not attenuate (nor promote) increases in lean muscle mass in athletes. Post-resistance exercise CON or CWI results in trivial increases in SJ height, compared to HWI. During an in-season competition phase, our data support the continued use of post-resistance exercise whole-body CWI by athletes as a recovery strategy which does not attenuate body composition increases in lean muscle mass, while promoting trivial increases in neuromuscular concentric-only squat jump performance.


Asunto(s)
Entrenamiento de Fuerza , Humanos , Masculino , Rugby , Estudios Cruzados , Inmersión , Estaciones del Año , Agua , Composición Corporal , Frío
17.
J Sports Sci ; 41(20): 1875-1882, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38247026

RESUMEN

The aim of the current study was to determine whether daily fucoidan supplementation (Undaria pinnatifida extract containing >85% fucoidan, 1 g/day) for three-weeks in a double blind-placebo controlled cross-over trial (ACTRN12621000872831) could modulate alterations in faecal (calprotectin, lysozyme and IgA) and salivary (lactoferrin, lysozyme and IgA) markers of mucosal immune competence typically observed in response to both acute physical activity, and a period of intensified exercise training, in healthy recreationally active men (n = 12). Participants responded positively to the intensified training with 16-19% improvement in mean power that was not different between supplement groups. Faecal biomarkers and concentrations of lactoferrin, lysozyme and IgA from resting saliva samples were largely stable over the supplementation period. Concentrations of salivary biomarkers varied significantly over time in response to acute exercise, however differences between supplementation groups were modest. For salivary lysozyme, there was a trend for a lower magnitude of increase post-exercise (p = 0.08) and limited return towards pre-exercise in response to fucoidan. For salivary IgA, a greater acute exercise response was noted for IgA in response to fucoidan (~2.7-fold higher; p = 0.02). Different dosage and supplementation protocols and inclusion of additional immune markers should be considered in subsequent assessments of any potential benefits of fucoidan supplementation in healthy active adults.


Asunto(s)
Algas Comestibles , Lactoferrina , Muramidasa , Polisacáridos , Undaria , Adulto , Masculino , Humanos , Inmunoglobulina A , Biomarcadores , Saliva
18.
J Strength Cond Res ; 37(8): 1643-1653, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37043600

RESUMEN

ABSTRACT: Horgan, BG, Tee, N, West, NP, Drinkwater, EJ, Halson, SL, Colomer, CME, Fonda, CJ, Tatham, J, Chapman, DW, and Haff, GG. Acute performance, daily well-being and hormone responses to water immersion after resistance exercise in junior international and subelite male volleyball athletes. J Strength Cond Res 37(8): 1643-1653, 2023-Athletes use postexercise hydrotherapy strategies to improve recovery and competition performance and to enhance adaptative responses to training. Using a randomized cross-over design, the acute effects of 3 postresistance exercise water immersion strategies on perceived recovery, neuromuscular performance, and hormone concentrations in junior international and subelite male volleyball athletes ( n = 18) were investigated. After resistance exercise, subjects randomly completed either 15-minute passive control (CON), contrast water therapy (CWT), cold (CWI), or hot water immersion (HWI) interventions. A treatment effect occurred after HWI; reducing perceptions of fatigue (HWI > CWT: p = 0.05, g = 0.43); improved sleep quality, compared with CON ( p < 0.001, g = 1.15), CWI ( p = 0.017, g = 0.70), and CWT ( p = 0.018, g = 0.51); as well as increasing testosterone concentration (HWI > CWT: p = 0.038, g = 0.24). There were trivial to small ( p < 0.001-0.039, g = 0.02-0.34) improvements (treatment effect) in jump performance (i.e., squat jump and countermovement jump) after all water immersion strategies, as compared with CON, with high variability in the individual responses. There were no significant differences (interaction effect, p > 0.05) observed between the water immersion intervention strategies and CON in performance ( p = 0.153-0.99), hormone ( p = 0.207-0.938), nor perceptual ( p = 0.368-0.955) measures. To optimize recovery and performance responses, e.g., during an in-season competition phase, postresistance exercise HWI may assist with providing small-to-large improvements for up to 38 hours in perceived recovery (i.e., increased sleep quality and reduced fatigue) and increases in circulating testosterone concentration. Practitioners should consider individual athlete neuromuscular performance responses when prescribing postexercise hydrotherapy. These findings apply to athletes who aim to improve their recovery status, where postresistance exercise HWI optimizes sleep quality and next-day perceptions of fatigue.


Asunto(s)
Entrenamiento de Fuerza , Voleibol , Humanos , Masculino , Agua , Inmersión , Atletas , Fatiga , Testosterona , Frío
19.
Ann Surg ; 275(3): e549-e561, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-34238814

RESUMEN

OBJECTIVE: The aim of this study to describe a new international dataset for pathology reporting of colorectal cancer surgical specimens, produced under the auspices of the International Collaboration on Cancer Reporting (ICCR). BACKGROUND: Quality of pathology reporting and mutual understanding between colorectal surgeon, pathologist and oncologist are vital to patient management. Some pathology parameters are prone to variable interpretation, resulting in differing positions adopted by existing national datasets. METHODS: The ICCR, a global alliance of major pathology institutions with links to international cancer organizations, has developed and ratified a rigorous and efficient process for the development of evidence-based, structured datasets for pathology reporting of common cancers. Here we describe the production of a dataset for colorectal cancer resection specimens by a multidisciplinary panel of internationally recognized experts. RESULTS: The agreed dataset comprises eighteen core (essential) and seven non-core (recommended) elements identified from a review of current evidence. Areas of contention are addressed, some highly relevant to surgical practice, with the aim of standardizing multidisciplinary discussion. The summation of all core elements is considered to be the minimum reporting standard for individual cases. Commentary is provided, explaining each element's clinical relevance, definitions to be applied where appropriate for the agreed list of value options and the rationale for considering the element as core or non-core. CONCLUSIONS: This first internationally agreed dataset for colorectal cancer pathology reporting promotes standardization of pathology reporting and enhanced clinicopathological communication. Widespread adoption will facilitate international comparisons, multinational clinical trials and help to improve the management of colorectal cancer globally.


Asunto(s)
Neoplasias Colorrectales/patología , Conjuntos de Datos como Asunto/normas , Proyectos de Investigación , Humanos
20.
PLoS Pathog ; 16(2): e1008287, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32032366

RESUMEN

Our inability to predict which mutations could result in antibiotic resistance has made it difficult to rapidly identify the emergence of resistance, identify pre-existing resistant populations, and manage our use of antibiotics to effectively treat patients and prevent or slow the spread of resistance. Here we investigated the potential for resistance against the new antitubercular nitroimidazole prodrugs pretomanid and delamanid to emerge in Mycobacterium tuberculosis, the causative agent of tuberculosis (TB). Deazaflavin-dependent nitroreductase (Ddn) is the only identified enzyme within M. tuberculosis that activates these prodrugs, via an F420H2-dependent reaction. We show that the native menaquinone-reductase activity of Ddn is essential for emergence from hypoxia, which suggests that for resistance to spread and pose a threat to human health, the native activity of Ddn must be at least partially retained. We tested 75 unique mutations, including all known sequence polymorphisms identified among ~15,000 sequenced M. tuberculosis genomes. Several mutations abolished pretomanid and delamanid activation in vitro, without causing complete loss of the native activity. We confirmed that a transmissible M. tuberculosis isolate from the hypervirulent Beijing family already possesses one such mutation and is resistant to pretomanid, before being exposed to the drug. Notably, delamanid was still effective against this strain, which is consistent with structural analysis that indicates delamanid and pretomanid bind to Ddn differently. We suggest that the mutations identified in this work be monitored for informed use of delamanid and pretomanid treatment and to slow the emergence of resistance.


Asunto(s)
Antituberculosos/farmacología , Proteínas Bacterianas , Farmacorresistencia Bacteriana , Mutación , Mycobacterium tuberculosis , Nitroimidazoles/farmacología , Nitrorreductasas , Oxazoles/farmacología , Ingeniería de Proteínas , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Farmacorresistencia Bacteriana/efectos de los fármacos , Farmacorresistencia Bacteriana/genética , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Nitrorreductasas/genética , Nitrorreductasas/metabolismo , Polimorfismo Genético
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