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1.
Proc Natl Acad Sci U S A ; 121(6): e2304619121, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38289962

RESUMEN

Resistance to neoadjuvant chemotherapy leads to poor prognosis of locally advanced rectal cancer (LARC), representing an unmet clinical need that demands further exploration of therapeutic strategies to improve clinical outcomes. Here, we identified a noncanonical role of RB1 for modulating chromatin activity that contributes to oxaliplatin resistance in colorectal cancer (CRC). We demonstrate that oxaliplatin induces RB1 phosphorylation, which is associated with the resistance to neoadjuvant oxaliplatin-based chemotherapy in LARC. Inhibition of RB1 phosphorylation by CDK4/6 inhibitor results in vulnerability to oxaliplatin in both intrinsic and acquired chemoresistant CRC. Mechanistically, we show that RB1 modulates chromatin activity through the TEAD4/HDAC1 complex to epigenetically suppress the expression of DNA repair genes. Antagonizing RB1 phosphorylation through CDK4/6 inhibition enforces RB1/TEAD4/HDAC1 repressor activity, leading to DNA repair defects, thus sensitizing oxaliplatin treatment in LARC. Our study identifies a RB1 function in regulating chromatin activity through TEAD4/HDAC1. It also provides the combination of CDK4/6 inhibitor with oxaliplatin as a potential synthetic lethality strategy to mitigate oxaliplatin resistance in LARC, whereby phosphorylated RB1/TEAD4 can serve as potential biomarkers to guide the patient stratification.


Asunto(s)
Terapia Neoadyuvante , Neoplasias del Recto , Humanos , Oxaliplatino/farmacología , Terapia Neoadyuvante/métodos , Neoplasias del Recto/tratamiento farmacológico , Neoplasias del Recto/genética , Quimioradioterapia/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Cromatina , Resultado del Tratamiento , Factores de Transcripción de Dominio TEA , Ubiquitina-Proteína Ligasas , Proteínas de Unión a Retinoblastoma
2.
Blood ; 143(18): 1837-1844, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38170173

RESUMEN

ABSTRACT: Idiopathic multicentric Castleman disease (iMCD) is a rare cytokine-driven disorder characterized by systemic inflammation, generalized lymphadenopathy, and organ dysfunction. Here, we present an unusual occurrence of iMCD in identical twins and examined the immune milieu within the affected lymphoid organs and the host circulation using multiomic high-dimensional profiling. Using spatial enhanced resolution omics sequencing (Stereo-seq) transcriptomic profiling, we performed unsupervised spatially constrained clustering to identify different anatomic structures, mapping the follicles and interfollicular regions. After a cell segmentation approach, interleukin 6 (IL-6) pathway genes significantly colocalized with endothelial cells and fibroblastic reticular cells, confirming observations using a single-cell sequencing approach (10× Chromium). Furthermore, single-cell sequencing of peripheral blood mononuclear cells revealed an "inflammatory" peripheral monocytosis enriched for the expression of S100A family genes in both twins. In summary, we provided evidence of the putative cell-of-origin of IL-6 signals in iMCD and described a distinct monocytic host immune response phenotype through a unique identical twin model.


Asunto(s)
Enfermedad de Castleman , Interleucina-6 , Análisis de la Célula Individual , Gemelos Monocigóticos , Humanos , Enfermedad de Castleman/patología , Enfermedad de Castleman/genética , Gemelos Monocigóticos/genética , Interleucina-6/genética , Interleucina-6/metabolismo , Masculino , Femenino , Enfermedades en Gemelos/genética , Enfermedades en Gemelos/patología , Persona de Mediana Edad , Perfilación de la Expresión Génica
3.
Proc Natl Acad Sci U S A ; 120(31): e2302020120, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37487092

RESUMEN

In the United States, the onset of COVID-19 triggered a nationwide lockdown, which forced many universities to move their primary assessments from invigilated in-person exams to unproctored online exams. This abrupt change occurred midway through the Spring 2020 semester, providing an unprecedented opportunity to investigate whether online exams can provide meaningful assessments of learning relative to in-person exams on a per-student basis. Here, we present data from nearly 2,000 students across 18 courses at a large Midwestern University. Using a meta-analytic approach in which we treated each course as a separate study, we showed that online exams produced scores that highly resembled those from in-person exams at an individual level despite the online exams being unproctored-as demonstrated by a robust correlation between online and in-person exam scores. Moreover, our data showed that cheating was either not widespread or ineffective at boosting scores, and the strong assessment value of online exams was observed regardless of the type of questions asked on the exam, the course level, academic discipline, or class size. We conclude that online exams, even when unproctored, are a viable assessment tool.


Asunto(s)
COVID-19 , Humanos , Control de Enfermedades Transmisibles , Estudiantes , Aprendizaje , Estaciones del Año
4.
Nat Methods ; 19(9): 1137-1146, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36050489

RESUMEN

Antibodies have diverse applications due to their high reaction specificities but are sensitive to denaturation when a higher working temperature is required. We have developed a simple, highly scalable and generalizable chemical approach for stabilizing off-the-shelf antibodies against thermal and chemical denaturation. We demonstrate that the stabilized antibodies (termed SPEARs) can withstand up to 4 weeks of continuous heating at 55 °C and harsh denaturants, and apply our method to 33 tested antibodies. SPEARs enable flexible applications of thermocycling and denaturants to dynamically modulate their binding kinetics, reaction equilibrium, macromolecular diffusivity and aggregation propensity. In particular, we show that SPEARs permit the use of a thermally facilitated three-dimensional immunolabeling strategy (termed ThICK staining), achieving whole mouse brain immunolabeling within 72 h, as well as nearly fourfold deeper penetration with threefold less antibodies in human brain tissue. With faster deep-tissue immunolabeling and broad compatibility with tissue processing and clearing methods without the need for any specialized equipment, we anticipate the wide applicability of ThICK staining with SPEARs for deep immunostaining.


Asunto(s)
Anticuerpos , Encéfalo , Animales , Anticuerpos/metabolismo , Encéfalo/metabolismo , Humanos , Ratones
5.
Lab Invest ; 104(3): 100323, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38218317

RESUMEN

Recent studies have described several molecular subtypes and deregulation of immuno-oncologic signaling pathways in angiosarcoma. Interestingly, mast cells were enriched in subsets of angiosarcoma, although their significance remains unknown. In this study, we aim to verify this observation using immunohistochemistry (H scores) and NanoString transcriptomic profiling and explore the association between mast cells with clinical and biological features. In the study cohort (N = 60), H scores showed a significant moderate correlation with NanoString mast cell scores (r = 0.525; P < .001). Both H score and NanoString mast cell scores showed a significant positive correlation (P < .05) with head and neck location, nonepithelioid morphology, and lower tumor grade. Mast cell enrichment significantly correlated with higher NanoString regulatory T-cell scores (H score, r = 0.32; P = .01; NanoString mast cell score, r = 0.27; P = .04). NanoString mast cell scores positively correlated with signaling pathways relating to antigen presentation (r = 0.264; P = .0414) and negatively correlated with apoptosis (r = -0.366; P = .0040), DNA damage repair (r = -0.348; P = .0064), and cell proliferation (r = -0.542; P < .001). Interestingly, in the metastatic setting, patients with mast cell-enriched angiosarcoma showed poorer progression-free survival (median, 0.2 vs 0.4 years; hazard ratio = 3.05; P = .0489) along with a trend toward worse overall survival (median, 0.2 vs 0.6 years; hazard ratio, 2.86; P = .0574) compared with patients with mast cell-poor angiosarcoma. In conclusion, we demonstrated the presence of mast cells in human angiosarcoma and provided initial evidence of their potential clinical and biological significance. Future research will be required to elucidate their specific roles and mechanisms, which may uncover novel avenues for therapeutic intervention.


Asunto(s)
Hemangiosarcoma , Humanos , Hemangiosarcoma/patología , Hemangiosarcoma/terapia , Mastocitos , Transducción de Señal , Apoptosis , Pronóstico
6.
Respir Res ; 25(1): 194, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38702779

RESUMEN

Asthma is a common chronic disease amongst children. Epidemiological studies showed that the mortality rate of asthma in children is still high worldwide. Asthma control is therefore essential to minimize asthma exacerbations, which can be fatal if the condition is poorly controlled. Frequent monitoring could help to detect asthma progression and ensure treatment effectiveness. Although subjective asthma monitoring tools are available, the results vary as they rely on patients' self-perception. Emerging evidence suggests several objective tools could have the potential for monitoring purposes. However, there is no consensus to standardise the use of objective monitoring tools. In this review, we start with the prevalence and severity of childhood asthma worldwide. Then, we detail the latest available objective monitoring tools, focusing on their effectiveness in paediatric asthma management. Publications of spirometry, fractional exhaled nitric oxide (FeNO), hyperresponsiveness tests and electronic monitoring devices (EMDs) between 2016 and 2023 were included. The potential advantages and limitations of each tool were also discussed. Overall, this review provides a summary for researchers dedicated to further improving objective paediatric asthma monitoring and provides insights for clinicians to incorporate different objective monitoring tools in clinical practices.


Asunto(s)
Asma , Humanos , Asma/diagnóstico , Asma/terapia , Asma/fisiopatología , Asma/epidemiología , Niño , Espirometría/métodos , Monitoreo Fisiológico/métodos , Manejo de la Enfermedad , Prueba de Óxido Nítrico Exhalado Fraccionado/métodos
7.
Curr Oncol Rep ; 26(7): 840-854, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38777980

RESUMEN

BACKGROUND: The journey from radical treatments to the precision of robotic surgery underscores a commitment to innovation and patient-centered care in the field of head and neck oncology. PURPOSE OF REVIEW: This article provides a comprehensive overview that not only informs but also stimulates ongoing discourse and investigation into the optimization of patient care through robotic surgery. The literature on current robotic applications within head and neck region was systematically reviewed. RECENT FINDINGS: Thirty-four studies with a total of 1835 patients undergoing robotic surgery in head and neck region were included. Clinical staging, histological types, operative duration, postoperative complications, functional recovery and survival outcomes were compared and evaluated. Clinical outcomes have shown promising results and thus the indication on the robotic usage has no longer been limited to oropharyngeal region but from skull base to neck dissection. The latest advancement in robotic surgery further refines the capabilities of surgeons into previously difficult-to-access head and neck regions and heralds a new era of surgical treatment for head and neck oncology.


Asunto(s)
Neoplasias de Cabeza y Cuello , Procedimientos Quirúrgicos Robotizados , Humanos , Neoplasias de Cabeza y Cuello/cirugía , Neoplasias de Cabeza y Cuello/patología , Procedimientos Quirúrgicos Robotizados/métodos
8.
J Appl Clin Med Phys ; 25(1): e14239, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38128040

RESUMEN

BACKGROUND: Magnetic resonance image only (MRI-only) simulation for head and neck (H&N) radiotherapy (RT) could allow for single-image modality planning with excellent soft tissue contrast. In the MRI-only simulation workflow, synthetic computed tomography (sCT) is generated from MRI to provide electron density information for dose calculation. Bone/air regions produce little MRI signal which could lead to electron density misclassification in sCT. Establishing the dosimetric impact of this error could inform quality assurance (QA) procedures using MRI-only RT planning or compensatory methods for accurate dosimetric calculation. PURPOSE: The aim of this study was to investigate if Hounsfield unit (HU) voxel misassignments from sCT images result in dosimetric errors in clinical treatment plans. METHODS: Fourteen H&N cancer patients undergoing same-day CT and 3T MRI simulation were retrospectively identified. MRI was deformed to the CT using multimodal deformable image registration. sCTs were generated from T1w DIXON MRIs using a commercially available deep learning-based generator (MRIplanner, Spectronic Medical AB, Helsingborg, Sweden). Tissue voxel assignment was quantified by creating a CT-derived HU threshold contour. CT/sCT HU differences for anatomical/target contours and tissue classification regions including air (<250 HU), adipose tissue (-250 HU to -51 HU), soft tissue (-50 HU to 199 HU), spongy (200 HU to 499 HU) and cortical bone (>500 HU) were quantified. t-test was used to determine if sCT/CT HU differences were significant. The frequency of structures that had a HU difference > 80 HU (the CT window-width setting for intra-cranial structures) was computed to establish structure classification accuracy. Clinical intensity modulated radiation therapy (IMRT) treatment plans created on CT were retrospectively recalculated on sCT images and compared using the gamma metric. RESULTS: The mean ratio of sCT HUs relative to CT for air, adipose tissue, soft tissue, spongy and cortical bone were 1.7 ± 0.3, 1.1 ± 0.1, 1.0 ± 0.1, 0.9 ± 0.1 and 0.8 ± 0.1 (value of 1 indicates perfect agreement). T-tests (significance set at t = 0.05) identified differences in HU values for air, spongy and cortical bone in sCT images compared to CT. The structures with sCT/CT HU differences > 80 HU of note were the left and right (L/R) cochlea and mandible (>79% of the tested cohort), the oral cavity (for 57% of the tested cohort), the epiglottis (for 43% of the tested cohort) and the L/R TM joints (occurring > 29% of the cohort). In the case of the cochlea and TM joints, these structures contain dense bone/air interfaces. In the case of the oral cavity and mandible, these structures suffer the additional challenge of being positionally altered in CT versus MRI simulation (due to a non-MR safe immobilizing bite block requiring absence of bite block in MR). Finally, the epiglottis HU assignment suffers from its small size and unstable positionality. Plans recalculated on sCT yielded global/local gamma pass rates of 95.5% ± 2% (3 mm, 3%) and 92.7% ± 2.1% (2 mm, 2%). The largest mean differences in D95, Dmean , D50 dose volume histogram (DVH) metrics for organ-at-risk (OAR) and planning tumor volumes (PTVs) were 2.3% ± 3.0% and 0.7% ± 1.9% respectively. CONCLUSIONS: In this cohort, HU differences of CT and sCT were observed but did not translate into a reduction in gamma pass rates or differences in average PTV/OAR dose metrics greater than 3%. For sites such as the H&N where there are many tissue interfaces we did not observe large scale dose deviations but further studies using larger retrospective cohorts are merited to establish the variation in sCT dosimetric accuracy which could help to inform QA limits on clinical sCT usage.


Asunto(s)
Aprendizaje Profundo , Humanos , Estudios Retrospectivos , Planificación de la Radioterapia Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Dosificación Radioterapéutica , Imagen por Resonancia Magnética/métodos
9.
Int J Mol Sci ; 25(10)2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38791152

RESUMEN

Since the launch of this Special Issue entitled "Cancer Immunotherapy: Tumor Microenvironment, Biomarker Discovery and Immune Resistance", the field of cancer immunotherapy has continued to witness rapid growth in the development of novel agents, improvements in our understanding of mechanisms of response and resistance, and the maturation of emerging technologies such as artificial intelligence, machine learning, single-cell sequencing and spatial profiling [...].


Asunto(s)
Biomarcadores de Tumor , Inmunoterapia , Neoplasias , Microambiente Tumoral , Microambiente Tumoral/inmunología , Humanos , Inmunoterapia/métodos , Neoplasias/inmunología , Neoplasias/terapia , Resistencia a Antineoplásicos
10.
Gut ; 2023 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-38050079

RESUMEN

OBJECTIVES: Cholangiocarcinoma (CCA) is a heterogeneous malignancy with high mortality and dismal prognosis, and an urgent clinical need for new therapies. Knowledge of the CCA epigenome is largely limited to aberrant DNA methylation. Dysregulation of enhancer activities has been identified to affect carcinogenesis and leveraged for new therapies but is uninvestigated in CCA. Our aim is to identify potential therapeutic targets in different subtypes of CCA through enhancer profiling. DESIGN: Integrative multiomics enhancer activity profiling of diverse CCA was performed. A panel of diverse CCA cell lines, patient-derived and cell line-derived xenografts were used to study identified enriched pathways and vulnerabilities. NanoString, multiplex immunohistochemistry staining and single-cell spatial transcriptomics were used to explore the immunogenicity of diverse CCA. RESULTS: We identified three distinct groups, associated with different etiologies and unique pathways. Drug inhibitors of identified pathways reduced tumour growth in in vitro and in vivo models. The first group (ESTRO), with mostly fluke-positive CCAs, displayed activation in estrogen signalling and were sensitive to MTOR inhibitors. Another group (OXPHO), with mostly BAP1 and IDH-mutant CCAs, displayed activated oxidative phosphorylation pathways, and were sensitive to oxidative phosphorylation inhibitors. Immune-related pathways were activated in the final group (IMMUN), made up of an immunogenic CCA subtype and CCA with aristolochic acid (AA) mutational signatures. Intratumour differences in AA mutation load were correlated to intratumour variation of different immune cell populations. CONCLUSION: Our study elucidates the mechanisms underlying enhancer dysregulation and deepens understanding of different tumourigenesis processes in distinct CCA subtypes, with potential significant therapeutics and clinical benefits.

11.
Mol Cancer ; 22(1): 85, 2023 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-37210576

RESUMEN

BACKGROUND: Enhancer of zeste homolog 2 (EZH2), the key catalytic subunit of polycomb repressive complex 2 (PRC2), is overexpressed and plays an oncogenic role in various cancers through catalysis-dependent or catalysis-independent pathways. However, the related mechanisms contributing to ovarian cancer (OC) are not well understood. METHODS: The levels of EZH2 and H3K27me3 were evaluated in 105 OC patients by immunohistochemistry (IHC) staining, and these patients were stratified based on these levels. Canonical and noncanonical binding sites of EZH2 were defined by chromatin immunoprecipitation sequencing (ChIP-Seq). The EZH2 solo targets were obtained by integrative analysis of ChIP-Seq and RNA sequencing data. In vitro and in vivo experiments were performed to determine the role of EZH2 in OC growth. RESULTS: We showed that a subgroup of OC patients with high EZH2 expression but low H3K27me3 exhibited the worst prognosis, with limited therapeutic options. We demonstrated that induction of EZH2 degradation but not catalytic inhibition profoundly blocked OC cell proliferation and tumorigenicity in vitro and in vivo. Integrative analysis of genome-wide chromatin and transcriptome profiles revealed extensive EZH2 occupancy not only at genomic loci marked by H3K27me3 but also at promoters independent of PRC2, indicating a noncanonical role of EZH2 in OC. Mechanistically, EZH2 transcriptionally upregulated IDH2 to potentiate metabolic rewiring by enhancing tricarboxylic acid cycle (TCA cycle) activity, which contributed to the growth of OC. CONCLUSIONS: These data reveal a novel oncogenic role of EZH2 in OC and identify potential therapeutic strategies for OC by targeting the noncatalytic activity of EZH2.


Asunto(s)
Proteína Potenciadora del Homólogo Zeste 2 , Neoplasias Ováricas , Humanos , Femenino , Proteína Potenciadora del Homólogo Zeste 2/genética , Histonas/metabolismo , Complejo Represivo Polycomb 2/genética , Complejo Represivo Polycomb 2/metabolismo , Neoplasias Ováricas/patología , Metilación , Línea Celular Tumoral
12.
Int J Cancer ; 152(9): 1903-1915, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-36752573

RESUMEN

The bidirectional association between primary esophageal squamous cell carcinoma (ESCC) and oral cavity squamous cell carcinoma (OSCC) suggests common risk factors and oncogenic molecular processes but it is unclear whether these two cancers display similar patterns of dysbiosis in their upper aerodigestive microbiota (UADM). We conducted a case-control study to characterize the microbial communities in esophageal lavage samples from 49 ESCC patients and oral rinse samples from 91 OSCC patients using 16S rRNA V3-V4 amplicon sequencing. Compared with their respective non-SCC controls from the same anatomical sites, 32 and 45 discriminative bacterial genera were detected in ESCC and OSCC patients, respectively. Interestingly, 20 of them were commonly enriched or depleted in both types of cancer, suggesting a convergent niche adaptation of upper aerodigestive SCC-associated bacteria that may play important roles in the pathogenesis of malignancies. Notably, Fusobacterium, Selenomonas, Peptoanaerobacter and Peptostreptococcus were enriched in both ESCC and OSCC, whereas Streptococcus and Granulicatelia were commonly depleted. We further identified Fusobacterium nucleatum as the most abundant species enriched in the upper aerodigestive SCC microenvironment, and the higher relative abundances of Selenomonas danae and Treponema maroon were positively correlated with smoking. In addition, predicted functional analysis revealed several depleted (eg, lipoic acid and pyruvate metabolism) and enriched (eg, RNA polymerase and nucleotide excision repair) pathways common to both cancers. Our findings reveal a convergent dysbiosis in the UADM between patients with ESCC and OSCC, suggesting a shared niche adaptation of host-microbiota interactions in the pathogenesis of upper aerodigestive tract malignancies.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Neoplasias de Cabeza y Cuello , Microbiota , Neoplasias de la Boca , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello , Neoplasias Esofágicas/microbiología , Disbiosis/complicaciones , ARN Ribosómico 16S/genética , Estudios de Casos y Controles , Carcinoma de Células Escamosas/patología , Neoplasias de la Boca/microbiología , Bacterias/genética , Microbiota/genética , Microambiente Tumoral
13.
Mod Pathol ; 36(4): 100056, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36788078

RESUMEN

Mutations in the PI3K pathway, particularly PIK3CA, were reported to be intimately associated with triple-negative breast cancer (TNBC) progression and the development of treatment resistance. We profiled PIK3CA and other genes on 166 early-stage TNBC tumors from Singapore for comparison to publicly available TNBC cohorts. These tumors were profiled transcriptionally using a NanoString panel of immune genes and multiplex immunohistochemistry, then manually scored for PD-L1-positivity using 2 clinically relevant clones, SP142 and 22C3. We discovered a higher rate of PIK3CA mutations in our TNBC cohort than in non-Asian cohorts, along with TP53, BRCA1, PTPN11, and MAP3K1 alterations. PIK3CA mutations did not affect overall or recurrence-free survival, and when compared with PIK3CAWT tumors, there were no differences in immune infiltration. Using 2 clinically approved antibodies, PIK3CAmut tumors were associated with PD-L1 negativity. Analysis of comutation frequencies further revealed that PIK3CA mutations tended to be accompanied by MAP kinase pathway mutation. The mechanism and impact of PIK3CA alterations on the TNBC tumor immune microenvironment and PD-L1 positivity warrant further study.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Humanos , Neoplasias de la Mama Triple Negativas/patología , Antígeno B7-H1/genética , Singapur , Fosfatidilinositol 3-Quinasas/genética , Mutación , Fosfatidilinositol 3-Quinasa Clase I/genética , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/análisis , Microambiente Tumoral
14.
Exp Physiol ; 108(4): 636-649, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36754374

RESUMEN

NEW FINDINGS: What is the central question of this study? Is the attenuation of the respiratory muscle metaboreflex preserved after detraining? What is the main finding and its importance? Inspiratory muscle training increased respiratory muscle strength and attenuated the respiratory muscle metaboreflex as evident by lower heart rate and blood pressure. After 5 weeks of no inspiratory muscle training (detraining), respiratory muscle strength was still elevated and the metaboreflex was still attenuated. The benefits of inspiratory muscle training persist after cessation of training, and attenuation of the respiratory metaboreflex follows changes in respiratory muscle strength. ABSTRACT: Respiratory muscle training (RMT) improves respiratory muscle (RM) strength and attenuates the RM metaboreflex. However, the time course of muscle function loss after the absence of training or 'detraining' is less known and some evidence suggest the respiratory muscles atrophy faster than other muscles. We sought to determine the RM metaboreflex in response to 5 weeks of RMT and 5 weeks of detraining. An experimental group (2F, 6M; 26 ± 4years) completed 5 weeks of RMT and tibialis anterior (TA) training (each 5 days/week at 50% of maximal inspiratory pressure (MIP) and 50% maximal isometric force, respectively) followed by 5 weeks of no training (detraining) while a control group (1F, 7M; 24 ± 1years) underwent no intervention. Prior to training (PRE), post-training (POST) and post-detraining (DETR), all participants underwent a loaded breathing task (LBT) to failure (60% MIP) while heart rate and mean arterial blood pressure (MAP) were measured. Five weeks of training increased RM (18 ± 9%, P < 0.001) and TA (+34 ± 19%, P < 0.001) strength and both remained elevated after 5 weeks of detraining (MIP-POST vs. MIP-DETR: 154 ± 31 vs. 153 ± 28 cmH2O, respectively, P = 0.853; TA-POST vs. TA-DETR: 86 ± 19 vs. 85 ± 16 N, respectively, P = 0.982). However, the rise in MAP during LBT was attenuated POST (-11 ± 17%, P = 0.003) and DETR (-9 ± 9%, P = 0.007) during the iso-time LBT. The control group had no change in MIP (P = 0.33), TA strength (P = 0.385), or iso-time MAP (P = 0.867) during LBT across all time points. In conclusion, RM and TA have similar temporal strength gains and the attenuation of the respiratory muscle metaboreflex remains after 5 weeks of detraining.


Asunto(s)
Respiración , Músculos Respiratorios , Humanos , Músculos Respiratorios/fisiología , Ejercicios Respiratorios , Músculos Intercostales , Músculo Esquelético , Fuerza Muscular/fisiología
15.
PLoS Comput Biol ; 18(11): e1010715, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36395331

RESUMEN

Cell-cell interactions shape cellular function and ultimately organismal phenotype. Interacting cells can sense their mutual distance using combinations of ligand-receptor pairs, suggesting the existence of a spatial code, i.e., signals encoding spatial properties of cellular organization. However, this code driving and sustaining the spatial organization of cells remains to be elucidated. Here we present a computational framework to infer the spatial code underlying cell-cell interactions from the transcriptomes of the cell types across the whole body of a multicellular organism. As core of this framework, we introduce our tool cell2cell, which uses the coexpression of ligand-receptor pairs to compute the potential for intercellular interactions, and we test it across the Caenorhabditis elegans' body. Leveraging a 3D atlas of C. elegans' cells, we also implement a genetic algorithm to identify the ligand-receptor pairs most informative of the spatial organization of cells across the whole body. Validating the spatial code extracted with this strategy, the resulting intercellular distances are negatively correlated with the inferred cell-cell interactions. Furthermore, for selected cell-cell and ligand-receptor pairs, we experimentally confirm the communicatory behavior inferred with cell2cell and the genetic algorithm. Thus, our framework helps identify a code that predicts the spatial organization of cells across a whole-animal body.


Asunto(s)
Caenorhabditis elegans , Comunicación Celular , Animales , Ligandos , Comunicación , Fenotipo
16.
BMC Anesthesiol ; 23(1): 33, 2023 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-36703120

RESUMEN

BACKGROUND: The optimal treatment of hypotension during spinal anaesthesia is uncertain. A novel double intravenous vasopressor automated (DIVA) system reduces hypotension compared to standard care, and was subsequently modified to an advanced-DIVA (ADIVA) system. The primary objective was to compare ADIVA versus DIVA on incidence of hypotension (systolic BP (SBP) < 80% baseline). METHODS: We conducted a randomized-controlled trial in women undergoing elective cesarean delivery under spinal anesthesia. SBP and heart rate were measured continuously using a Nexfin monitor. ADIVA delivered 25 µg phenylephrine (heart rate > 60 beats.min-1) or 2 mg ephedrine (heart rate < 60 beats.min-1) at SBP 90 to 110% of baseline, 50 µg phenylephrine or 4 mg ephedrine at SBP 80 to 90%, and 75 µg phenylephrine or 6 mg ephedrine at SBP < 80%. ADIVA calculated the trend of SBP; vasopressors were administered rapidly if SBP trended downward, or 30 s if SBP trended upward. In contrast, DIVA delivered 25 µg phenylephrine or 2 mg ephedrine at SBP 90 to 100% of baseline, and 50 µg phenylephrine or 4 mg ephedrine at SBP < 90%. Boluses were followed by a 10-s lockout. Other outcomes included hypertension (SBP > 120% baseline), vasopressor consumption, clinical outcomes, and performance measures from spinal anesthesia to fetal delivery. RESULTS: We analyzed 94 parturients (ADIVA: n = 46, DIVA: n = 48), with no difference in the incidence of hypotension between ADIVA (78.3%) and DIVA (83.3%, p = 0.677). ADIVA had significantly higher proportion of hypotensive SBP readings, lower phenylephrine consumption and higher umbilical arterial pH. There was no difference in hypertension, bradycardia, ephedrine consumption, intravenous fluid volume, nausea/vomiting, Apgar scores, and umbilical venous pH or lactate. ADIVA maintained SBP higher above baseline with greater fluctuation than DIVA. CONCLUSION: ADIVA was associated with a greater proportion of hypotensive SBP readings, reduced phenylephrine consumption, and increased umbilical arterial pH than DIVA. Further research is needed to determine the optimal method of vasopressor delivery in parturients undergoing cesarean delivery. TRIAL REGISTRATION: This study was registered on Clinicaltrials.gov registry (NCT03620942) on 08/08/2018.


Asunto(s)
Anestesia Obstétrica , Anestesia Raquidea , Hipertensión , Hipotensión , Embarazo , Femenino , Humanos , Efedrina/uso terapéutico , Anestesia Raquidea/efectos adversos , Anestesia Raquidea/métodos , Vasoconstrictores/uso terapéutico , Hipotensión/inducido químicamente , Hipotensión/tratamiento farmacológico , Fenilefrina/uso terapéutico , Hipertensión/complicaciones , Anestesia Obstétrica/efectos adversos , Anestesia Obstétrica/métodos , Método Doble Ciego
17.
Clin Otolaryngol ; 48(5): 756-765, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37212448

RESUMEN

OBJECTIVES: To compare post-treatment neck and shoulder function between human papillomavirus-associated oropharynx squamous cell carcinoma (HPV + OPSCC) treatments. DESIGN: Prospective, repeated-measures study. SETTING: Tertiary care center. PARTICIPANTS: Treatment-naïve patients with American Joint Committee on Cancer eighth edition stage T0-3/N0-2 HPV+OPSCC. MAIN OUTCOME MEASURES: Patients completed the Neck Dissection Impairment Index (NDII) pre-treatment and 3-months and 1-year post-treatment. The NDII assesses 10 neck and shoulder functions scored 0-5 (total score 0-100), with higher scores suggesting better function. RESULTS: A total of 106 patients underwent: surgery alone (SA, n = 46, 43%), surgery with adjuvant radiation ± chemotherapy (S + a[C]XRT, n = 18, 17%), or definitive radiation ± chemotherapy (d[C]XRT, n = 42, 40%). cTN classification and pre-treatment NDII scores did not differ between groups. SA patients reported worsened 3-month post-treatment versus pre-treatment self-care (4.6 vs. 5.0), lifting light (4.6 vs. 5.0) and heavy (4.2 vs. 4.8) objects, overhead reach (4.5 vs. 4.9), activity (4.5 vs. 4.9), socialization (4.7 vs. 4.9), recreation (4.6 vs. 4.9), and overall score (86.8 vs. 95.3) (all p < 0.05). One-year post-treatment scores (n = 34) were no different than pre-treatment in all domains. S + a[C]XRT patients reported worsened 3-month versus pre-treatment stiffness (4.0 vs. 4.8), lifting heavy objects (3.8 vs. 4.9), overhead reach (4.2 vs. 4.9), socialization (4.6 vs. 5.0), recreation (4.4 vs. 4.9) and overall score (82.4 vs. 96.0) (all p < 0.05). One-year post-treatment scores (n = 13) were no different than pre-treatment in all domains. d[C]XRT patients reported worsened 3-month versus pre-treatment difficulty lifting heavy objects (4.3 vs. 4.7) and recreation (4.3 vs. 4.7). One-year posttreatment scores (n = 21) were no different than pre-treatment in all domains. CONCLUSION: HPV + OPSCC patients may experience mild shoulder/neck dysfunction 3 months after treatment that usually resolves by 1 year, independent of treatment modality.

18.
Can Assoc Radiol J ; 74(2): 398-403, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36399106

RESUMEN

Objective: To investigate the effect of double reads by a second radiologist on cancer detection rate (CDR), positive predictive value of recommendation for tissue diagnosis (PPV2), and the positive predictive value of biopsy performed (PPV3) for biopsy recommendations in high-risk screening breast MRIs. Methods: The policy of second reads on biopsies recommended for MRIs was prospectively implemented in October 2019. This IRB approved retrospective analysis compared consecutive high-risk screening breast MRI scans performed in a single academic institution between 06/01/2018 to 06/01/2019 (pre-intervention) with screening breast MRI scans performed between 10/31/2019 to 10/31/2020 (post-intervention). Pathology results after biopsy were recorded. Testing of association was performed using the Chi-square test. Results/Discussion: A total of 1124 screening breast MRIs in the pre-intervention and 1672 screening breast MRIs were performed in the post-intervention periods. Biopsies were recommended in 8.6% (97/1124) of pre-intervention and 5.5% (92/1672) of post-intervention MRIs (P = .0012). There was a non-significant increase in PPV2 from pre-intervention 10.3% (10/97) to post-intervention 18.4% (17/92) (P = .109) and in PPV3 from 14% (10/71) to 22.9% (17/74), respectively (P = .17). Similar cancer detection rates, 8.9/1000 (10/1124) and 10.2/1000 (17/1672) (P = .736) were diagnosed in pre-intervention and post-intervention periods, respectively. Conclusion: Double reading of screening breast MRI scans significantly reduced the number of unnecessary biopsies without significant impact in the PPVs or cancer detection rate.


Asunto(s)
Neoplasias de la Mama , Neoplasias , Humanos , Femenino , Estudios Retrospectivos , Detección Precoz del Cáncer/métodos , Mama/diagnóstico por imagen , Mamografía/métodos , Imagen por Resonancia Magnética/métodos , Tamizaje Masivo , Neoplasias de la Mama/patología
19.
Artículo en Inglés | MEDLINE | ID: mdl-38097211

RESUMEN

ISSUE ADDRESSED: The Deadly RED redesign and implementation research aimed to improve take own leave (TOL) rates within a Queensland emergency department by providing a culturally competent care pathway. METHODOLOGY: A mixed methods pre/post evaluation of the feasibility, acceptability and usability of the Deadly RED pathway for First Nations patients presenting to ED was performed. This pathway combined early welcome and information sharing, introduction of screening and follow up for patients who TOL and enhanced access to alternative community healthcare. Yarning circles facilitated co-design of research protocols and tools while a purposefully designed research Yarn enhanced understanding of the 'story' of the people. Qualitative analysis of Yarns allowed deductive themes to be extracted. A Participatory Action Research (PAR) approach and Indigenous research methodology involving First Nations people in design, knowledge sharing and joint ownership of results was used. RESULTS: Common themes from the 85 yarns included the negative impact of long waiting times and positive impact from wholistic care. Unique themes identified included interpretation of waiting room placement and paracetamol prescription as a dismissal. Knowledge dissemination from yarning drove improvements in communications and processes to promote treatment completion resulting in elimination of these themes in post implementation yarns. Eighteen patients who had TOL were included in the post implementation yarns, however only eight of these believed that their treatment was incomplete. CONCLUSION: The use of yarning for consumer engagement has allowed deeper understanding of the reasons for TOL in First Nations emergency patients. The reciprocal knowledge sharing has guided targeted improvements in wholistic emergency care and communication resulting in First Nations patients feeling their care is complete even when the 'number' reports otherwise. SO WHAT?: Indigenous Research methodology including yarning with First Nations patients suggests alternative engagement methods to guide enhanced quality of care monitoring for ED presentations.

20.
Semin Cancer Biol ; 74: 3-23, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33460766

RESUMEN

Oral cancers occurring in different subsites can have distinct etiologies' and are a significant problem worldwide. In general, the incidence of oral cancers has declined over the last decade due to improvements in modifiable risk factors (tobacco and alcohol consumption). However, recent data suggest that the incidence of squamous cell carcinomas in the oral tongue and oropharynx are increasing. Human papilloma virus (HPV) is an important risk factor for oropharyngeal cancer and is associated with better treatment responses when compared with HPV-unrelated oropharyngeal cancer. Regardless of the subsite, there are no clinically available biomarkers for the early detection of these cancers and many are detected at an advanced stage and are associated with poor 5-year survival rates. Tumor tissue and serial needle biopsies are used to diagnose and prognosticate oral cancers but have important limitations. Besides being invasive and physically painful, these types of biopsies offer a limited view of a complex tumor due to inter- and intra-tumoral heterogeneity and a dynamic tumor microenvironment. Liquid biopsies offer a promising and alternative way to measure disease in real-time. Extracellular vesicles (EVs) are small particles that are secreted by all cells types and can be readily isolated from a wide range of biofluids. EVs are structurally stable and can horizontally transfer bioactive molecules to distant sites throughout the body in concentrated forms that exceed what can be delivered in a soluble format. As EVs represent their cell of origin, biofluid derived EVs are heterogeneous and are comprised of a complex repertoire of host- and cancer-derived particles. This review article has focused on studies that have used transcriptomics and proteomics to explore the function and clinical significance of EVs in oral cavity and oropharyngeal cancers.


Asunto(s)
Vesículas Extracelulares , Perfilación de la Expresión Génica/métodos , Neoplasias de la Boca , Animales , Biomarcadores de Tumor/metabolismo , Humanos , Proteómica , Transcriptoma
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