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1.
BJU Int ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953550

RESUMO

OBJECTIVES: To evaluate the utility of the 17-gene Genomic Prostate Score® (GPS; MDxHealth, Irvine, CA, USA) performed on prostate cancer at the positive margin of the radical prostatectomy (RP) for its association with risk of subsequent biochemical recurrence (BCR). PATIENTS AND METHODS: We designed a case-cohort for the outcome of BCR, selecting 223 from a cohort of 813 RP patients treated at Johns Hopkins from 2008 to 2017 with positive margins and available clinical data; of these, 213 had available tissue and clinical data. RNA was isolated from formalin-fixed paraffin-embedded tumour tissue adjacent to the positive surgical margin and the GPS was evaluable in 203 of these patients with a score ranging from 0 to 100, with higher scores indicating higher risk. All patients underwent RP with or without adjuvant radiation therapy (ART). The statistical analysis employed Cox proportional hazards regression models for outcome of BCR weighted for case-cohort design. RESULTS: In univariable analysis, every 20-unit increase in the GPS was associated with a nearly threefold increase in risk of BCR (hazard ratio [HR] per 20 units 2.82, P < 0.001). In a multivariable Cox model adjusted for age, race, Cancer of the Prostate Risk Assessment Postsurgical score, Grade Group at the positive margin, and ART, the GPS was significantly associated with BCR (HR 1.56 per 20 units; 95% confidence interval 1.11-2.19; P = 0.011). The study is limited by its retrospective and single institution design. CONCLUSIONS: The GPS at the positive surgical margin could help stratify prognosis and inform clinical decision-making regarding adjuvant therapy after RP.

2.
BMJ Open ; 14(6): e076763, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858157

RESUMO

INTRODUCTION: Transurethral resection of bladder tumour (TURBT) is one of the more common procedures performed by urologists. It is often described as an 'incision-free' and 'well-tolerated' operation. However, many patients experience distress and discomfort with the procedure. Substantial opportunity exists to improve the TURBT experience. An enhanced recovery after surgery (ERAS) protocol designed by patients with bladder cancer and their providers has been developed. METHODS AND ANALYSIS: This is a single-centre, randomised controlled trial to investigate the effectiveness of an ERAS protocol compared with usual care in patients with bladder cancer undergoing ambulatory TURBT. The ERAS protocol is composed of preoperative, intraoperative and postoperative components designed to optimise each phase of perioperative care. 100 patients with suspected or known bladder cancer aged ≥18 years undergoing initial or repeat ambulatory TURBT will be enrolled. The change in Quality of Recovery 15 score, a measure of the quality of recovery, between the day of surgery and postoperative day 1 will be compared between the ERAS and control groups. ETHICS AND DISSEMINATION: The trial has been approved by the Johns Hopkins Institutional Review Board #00392063. Participants will provide informed consent to participate before taking part in the study. Results will be reported in a separate publication. TRIAL REGISTRATION NUMBER: NCT05905276.


Assuntos
Neoplasias da Bexiga Urinária , Humanos , Neoplasias da Bexiga Urinária/cirurgia , Procedimentos Cirúrgicos Ambulatórios/métodos , Recuperação Pós-Cirúrgica Melhorada , Cistectomia/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Feminino , Masculino , Assistência Perioperatória/métodos
3.
J Natl Cancer Inst ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38889303

RESUMO

Deep learning (DL)-based algorithms to determine prostate cancer (PCa) Grade Group (GG) on biopsy slides have not been validated by comparison to clinical outcomes. We used a DL-based algorithm, AIRAProstate, to re-grade initial prostate biopsies in two independent PCa active surveillance (AS) cohorts. In a cohort initially diagnosed with GG1 PCa using only systematic biopsies (n = 138), upgrading of the initial biopsy to ≥GG2 by AIRAProstate was associated with rapid or extreme grade reclassification on AS (odds ratio 3.3, p = .04), whereas upgrading of the initial biopsy by contemporary uropathologist reviews was not associated with this outcome. In a contemporary validation cohort that underwent prostate magnetic resonance imaging before initial biopsy (n = 169), upgrading of the initial biopsy (all contemporary GG1 by uropathologist grading) by AIRAProstate was associated with grade reclassification on AS (hazard ratio 1.7, p = .03). These results demonstrate the utility of a DL-based grading algorithm in PCa risk stratification for AS.

4.
Adv Sci (Weinh) ; : e2401467, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884161

RESUMO

Studying brain-wide hemodynamic responses to different stimuli at high spatiotemporal resolutions can help gain new insights into the mechanisms of neuro- diseases and -disorders. Nonetheless, this task is challenging, primarily due to the complexity of neurovascular coupling, which encompasses interdependent hemodynamic parameters including cerebral blood volume (CBV), cerebral blood flow (CBF), and cerebral oxygen saturation (SO2). The current brain imaging technologies exhibit inherent limitations in resolution, sensitivity, and imaging depth, restricting their capacity to comprehensively capture the intricacies of cerebral functions. To address this, a multimodal functional ultrasound and photoacoustic (fUSPA) imaging platform is reported, which integrates ultrafast ultrasound and multispectral photoacoustic imaging methods in a compact head-mountable device, to quantitatively map individual dynamics of CBV, CBF, and SO2 as well as contrast agent enhanced brain imaging at high spatiotemporal resolutions. Following systematic characterization, the fUSPA system is applied to study brain-wide cerebrovascular reactivity (CVR) at single-vessel resolution via relative changes in CBV, CBF, and SO2 in response to hypercapnia stimulation. These results show that cortical veins and arteries exhibit differences in CVR in the stimulated state and consistent anti-correlation in CBV oscillations during the resting state, demonstrating the multiparametric fUSPA system's unique capabilities in investigating complex mechanisms of brain functions.

5.
Eur J Cancer ; 207: 114160, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38896997

RESUMO

BACKGROUND: The liver is the most frequent site of metastases in colorectal cancer (CRC). This study aimed to assess the response rate and survival outcomes in metastatic CRC patients with non-liver metastases (NLM) compared to those with liver metastases (LM) across different lines of treatment. METHODS: A total of 17,924 mCRC patients included in 26 trials from the ARCAD CRC database were analyzed. The analysis was conducted based on the presence or absence of LM across different treatment groups: chemotherapy (CT) alone, CT + anti-VEGF, CT + anti-EGFR in KRAS wild-type tumors, within the first-line (1 L) and second-line (2 L), and patients enrolled in third-line (≥3 L) trials treated with trifluridine/tipiracil or regorafenib or placebo. The endpoints were overall survival (OS), progression-free survival (PFS), and overall response rate (ORR). RESULTS: Out of the 17,924 patients, 14,066 had LM (30.6 % with only liver involvement and 69.4 % with liver and other metastatic sites), while 3858 patients had NLM. In the CT alone and CT + anti-VEGF subgroups, NLM patients showed better OS and PFS in the 1 L and 2 L settings. However, in the CT + anti-EGFR 1 L and 2 L subgroups, there was no significant difference in OS and PFS between NLM and LM patients. In the ≥ 3 L subgroups, better OS and PFS were observed in NLM patients. ORRs were higher in LM patients than in NLM patients across all cohorts treated in the 1 L and only in the anti-EGFR cohort in the 2 L. CONCLUSION: LM is a poor prognostic factor for mCRC increasing from 1 L to ≥ 3 L except for patients in 1 L and 2 L receiving CT+anti-EGFR. These data justify using LM as a stratification factor in future trials for patients with unresectable mCRC.

6.
Front Netw Physiol ; 4: 1379892, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38831910

RESUMO

Fractal time series have been argued to be ubiquitous in human physiology and some of the implications of that ubiquity are quite remarkable. One consequence of the omnipresent fractality is complexity synchronization (CS) observed in the interactions among simultaneously recorded physiologic time series discussed herein. This new kind of synchronization has been revealed in the interaction triad of organ-networks (ONs) consisting of the mutually interacting time series generated by the brain (electroencephalograms, EEGs), heart (electrocardiograms, ECGs), and lungs (Respiration). The scaled time series from each member of the triad look nothing like one another and yet they bear a deeply recorded synchronization invisible to the naked eye. The theory of scaling statistics is used to explain the source of the CS observed in the information exchange among these multifractal time series. The multifractal dimension (MFD) of each time series is a measure of the time-dependent complexity of that time series, and it is the matching of the MFD time series that provides the synchronization referred to as CS. The CS is one manifestation of the hypothesis given by a "Law of Multifractal Dimension Synchronization" (LMFDS) which is supported by data. Therefore, the review aspects of this paper are chosen to make the extended range of the LMFDS hypothesis sufficiently reasonable to warrant further empirical testing.

7.
bioRxiv ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38915719

RESUMO

Almost every organ consists of many cell types, each with its unique functions. Proteomes of these cell types are thus unique too. But it is reasonable to assume that interactome (inter and intra molecular interactions of proteins) are also distinct since protein interactions are what ultimately carry out the function. Podocytes and tubules are two cell types within kidney with vastly different functions: podocytes envelop the blood vessels in the glomerulus and act as filters while tubules are located downstream of the glomerulus and are responsible for reabsorption of important nutrients. It has been long known that for tubules mitochondria plays an important role as they require a lot of energy to carry out their functions. In podocytes, however, it has been assumed that mitochondria might not matter as much in both normal physiology and pathology1. Here we have applied quantitative cross-linking mass spectrometry to compare mitochondrial interactomes of tubules and podocytes using a transgenic mitochondrial tagging strategy to immunoprecipitate cell-specific mitochondria directly from whole kidney. We have uncovered that mitochondrial proteomes of these cell types are quite similar, although still showing unique features that correspond to known functions, such as high energy production through TCA cycle in tubules and requirements for detoxification in podocytes which are on the frontline of filtration where they encounter toxic compounds and therefore, as a non-renewing cell type they must have ways to protect themselves from cellular toxicity. But we gained much deeper insight with the interactomics data. We were able to find pathways differentially regulated in podocytes and tubules based on changing cross-link levels and not just protein levels. Among these pathways are betaine metabolism, lysine degradation, and many others. We have also demonstrated how quantitative interactomics could be used to detect different activity levels of an enzyme even when protein abundances of it are the same between cell types. We have validated this finding with an orthogonal activity assay. Overall, this work presents a new view of mitochondrial biology for two important, but functionally distinct, cell types within the mouse kidney showing both similarities and unique features. This data can continue to be explored to find new aspects of mitochondrial biology, especially in podocytes, where mitochondria has been understudied. In the future this methodology can also be applied to other organs to uncover differences in the function of cell types.

8.
NPJ Prim Care Respir Med ; 34(1): 14, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834570

RESUMO

The FRESHAIR4Life study aims to reduce the non-communicable disease (NCD) burden by implementing preventive interventions targeting adolescents' exposure to tobacco use and air pollution (AP) worldwide. This paper presents the FRESHAIR4Life methodology and initial rapid review results. The rapid review, using various databases and PubMed, aimed to guide decision-making on risk factor focus, target areas, and populations. It showed variable NCD mortality rates related to tobacco use and AP across the participating countries, with tobacco as the main risk factor in the Kyrgyz Republic, Greece, and Romania, and AP prevailing in Pakistan and Uganda. Adolescent exposure levels, sources, and correlates varied. The study will continue with an in-depth situational analysis to guide the selection, adaptation, and integration of evidence-based interventions into the FRESHAIR4Life prevention package. This package will be implemented, evaluated, assessed for cost-effectiveness, and iteratively refined. The research places a strong emphasis on co-creation, capacity building, and comprehensive communication and dissemination.


Assuntos
Poluição do Ar , Doenças não Transmissíveis , Humanos , Adolescente , Poluição do Ar/efeitos adversos , Doenças não Transmissíveis/prevenção & controle , Populações Vulneráveis , Uso de Tabaco/prevenção & controle , Romênia , Paquistão , Uganda/epidemiologia , Grécia/epidemiologia , Exposição Ambiental/efeitos adversos , Exposição Ambiental/prevenção & controle , Saúde Global , Fatores de Risco
9.
Bull World Health Organ ; 102(6): 400-409, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38812802

RESUMO

Objective: To assess the effectiveness of a community-based tuberculosis and leprosy intervention in which village health teams and health workers conduct door-to-door tuberculosis screening, targeted screenings and contact tracing. Methods: We conducted a before-and-after implementation study in Uganda to assess the effectiveness of the community tuberculosis intervention by looking at reach, outputs, adoption and effectiveness of the intervention. Campaign 1 was conducted in March 2022 and campaign 2 in September 2022. We calculated percentages of targets achieved and compared case notification rates during the intervention with corresponding quarters in the previous year. We also assessed the leprosy screening. Findings: Over 5 days, campaign 1 screened 1 289 213 people (2.9% of the general population), of whom 179 144 (13.9%) fulfilled the presumptive tuberculosis criteria, and 4043 (2.3%) were diagnosed with bacteriologically-confirmed tuberculosis; 3710 (91.8%) individuals were linked to care. In campaign 2, 5 134 056 people (11.6% of the general population) were screened, detecting 428 444 (8.3%) presumptive tuberculosis patients and 8121 (1.9%) bacteriologically-confirmed tuberculosis patients; 5942 individuals (87.1%) were linked to care. The case notification rate increased from 48.1 to 59.5 per 100 000 population in campaign 1, with a case notification rate ratio of 1.24 (95% confidence interval, CI: 1.22-1.26). In campaign 2, the case notification rate increased from 45.0 to 71.6 per 100 000 population, with a case notification rate ratio of 1.59 (95% CI: 1.56-1.62). Of the 176 patients identified with leprosy, 137 (77.8%) initiated treatment. Conclusion: This community tuberculosis screening initiative is effective. However, continuous monitoring and adaptations are needed to overcome context-specific implementation challenges.


Assuntos
Programas de Rastreamento , Tuberculose , Humanos , Uganda/epidemiologia , Programas de Rastreamento/métodos , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Adulto , Feminino , Masculino , Adolescente , Busca de Comunicante/métodos , Pessoa de Meia-Idade , Hanseníase/diagnóstico , Hanseníase/epidemiologia , Adulto Jovem , Serviços de Saúde Comunitária/organização & administração , Criança , Pré-Escolar
10.
Cell Rep ; 43(6): 114259, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38819988

RESUMO

CD4+ T cells are central to adaptive immunity. Their role in cross-protection in viral infections such as influenza and severe acute respiratory syndrome (SARS) is well documented; however, molecular rules governing T cell receptor (TCR) engagement of peptide-human leukocyte antigen (pHLA) class II are less understood. Here, we exploit an aspect of HLA class II presentation, the peptide-flanking residues (PFRs), to "tune" CD4+ T cell responses within an in vivo model system of influenza. Using a recombinant virus containing targeted substitutions at immunodominant HLA-DR1 epitopes, we demonstrate limited weight loss and improved clinical scores after heterosubtypic re-challenge. We observe enhanced protection linked to lung-derived influenza-specific CD4+ and CD8+ T cells prior to re-infection. Structural analysis of the ternary TCR:pHLA complex identifies that flanking amino acids influence side chains in the core 9-mer peptide, increasing TCR affinity. Augmentation of CD4+ T cell immunity is achievable with a single mutation, representing a strategy to enhance adaptive immunity that is decoupled from vaccine modality.


Assuntos
Linfócitos T CD4-Positivos , Mutação , Receptores de Antígenos de Linfócitos T , Linfócitos T CD4-Positivos/imunologia , Humanos , Animais , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Antígenos de Linfócitos T/genética , Vírus da Influenza A/imunologia , Vírus da Influenza A/genética , Ativação Linfocitária/imunologia , Camundongos , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Epitopos/imunologia , Feminino , Linfócitos T CD8-Positivos/imunologia , Influenza Humana/imunologia , Influenza Humana/virologia , Influenza Humana/prevenção & controle
11.
Front Immunol ; 15: 1361891, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38711495

RESUMO

Background: To date, studies investigating the association between pre-biologic biomarker levels and post-biologic outcomes have been limited to single biomarkers and assessment of biologic efficacy from structured clinical trials. Aim: To elucidate the associations of pre-biologic individual biomarker levels or their combinations with pre-to-post biologic changes in asthma outcomes in real-life. Methods: This was a registry-based, cohort study using data from 23 countries, which shared data with the International Severe Asthma Registry (May 2017-February 2023). The investigated biomarkers (highest pre-biologic levels) were immunoglobulin E (IgE), blood eosinophil count (BEC) and fractional exhaled nitric oxide (FeNO). Pre- to approximately 12-month post-biologic change for each of three asthma outcome domains (i.e. exacerbation rate, symptom control and lung function), and the association of this change with pre-biologic biomarkers was investigated for individual and combined biomarkers. Results: Overall, 3751 patients initiated biologics and were included in the analysis. No association was found between pre-biologic BEC and pre-to-post biologic change in exacerbation rate for any biologic class. However, higher pre-biologic BEC and FeNO were both associated with greater post-biologic improvement in FEV1 for both anti-IgE and anti-IL5/5R, with a trend for anti-IL4Rα. Mean FEV1 improved by 27-178 mL post-anti-IgE as pre-biologic BEC increased (250 to 1000 cells/µL), and by 43-216 mL and 129-250 mL post-anti-IL5/5R and -anti-IL4Rα, respectively along the same BEC gradient. Corresponding improvements along a FeNO gradient (25-100 ppb) were 41-274 mL, 69-207 mL and 148-224 mL for anti-IgE, anti-IL5/5R, and anti-IL4Rα, respectively. Higher baseline BEC was also associated with lower probability of uncontrolled asthma (OR 0.392; p=0.001) post-biologic for anti-IL5/5R. Pre-biologic IgE was a poor predictor of subsequent pre-to-post-biologic change for all outcomes assessed for all biologics. The combination of BEC + FeNO marginally improved the prediction of post-biologic FEV1 increase (adjusted R2: 0.751), compared to BEC (adjusted R2: 0.747) or FeNO alone (adjusted R2: 0.743) (p=0.005 and <0.001, respectively); however, this prediction was not improved by the addition of IgE. Conclusions: The ability of higher baseline BEC, FeNO and their combination to predict biologic-associated lung function improvement may encourage earlier intervention in patients with impaired lung function or at risk of accelerated lung function decline.


Assuntos
Asma , Produtos Biológicos , Biomarcadores , Eosinófilos , Imunoglobulina E , Humanos , Asma/tratamento farmacológico , Asma/diagnóstico , Asma/imunologia , Masculino , Feminino , Pessoa de Meia-Idade , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Adulto , Eosinófilos/imunologia , Produtos Biológicos/uso terapêutico , Antiasmáticos/uso terapêutico , Resultado do Tratamento , Sistema de Registros , Índice de Gravidade de Doença , Contagem de Leucócitos , Óxido Nítrico/metabolismo , Idoso , Estudos de Coortes
12.
JAMA Netw Open ; 7(5): e2412432, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38753332

RESUMO

This cohort study investigates trends in total and per-physician industry-sponsored research payments to physician principal investigators from 2015 to 2022.


Assuntos
Pesquisadores , Humanos , Pesquisadores/economia , Apoio à Pesquisa como Assunto/economia , Apoio à Pesquisa como Assunto/tendências , Indústria Farmacêutica/economia , Médicos/economia , Estados Unidos , Pesquisa Biomédica/economia , Conflito de Interesses
13.
Hear Res ; 447: 109024, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38735179

RESUMO

Delayed loss of residual acoustic hearing after cochlear implantation is a common but poorly understood phenomenon due to the scarcity of relevant temporal bone tissues. Prior histopathological analysis of one case of post-implantation hearing loss suggested there were no interaural differences in hair cell or neural degeneration to explain the profound loss of low-frequency hearing on the implanted side (Quesnel et al., 2016) and attributed the threshold elevation to neo-ossification and fibrosis around the implant. Here we re-evaluated the histopathology in this case, applying immunostaining and improved microscopic techniques for differentiating surviving hair cells from supporting cells. The new analysis revealed dramatic interaural differences, with a > 80 % loss of inner hair cells in the cochlear apex on the implanted side, which can account for the post-implantation loss of residual hearing. Apical degeneration of the stria further contributed to threshold elevation on the implanted side. In contrast, spiral ganglion cell survival was reduced in the region of the electrode on the implanted side, but apical counts in the two ears were similar to that seen in age-matched unimplanted control ears. Almost none of the surviving auditory neurons retained peripheral axons throughout the basal half of the cochlea. Relevance to cochlear implant performance is discussed.


Assuntos
Limiar Auditivo , Implante Coclear , Implantes Cocleares , Gânglio Espiral da Cóclea , Implante Coclear/instrumentação , Implante Coclear/efeitos adversos , Humanos , Gânglio Espiral da Cóclea/patologia , Gânglio Espiral da Cóclea/fisiopatologia , Células Ciliadas Auditivas Internas/patologia , Fatores de Tempo , Sobrevivência Celular , Masculino , Audição , Perda Auditiva/fisiopatologia , Perda Auditiva/patologia , Perda Auditiva/cirurgia , Perda Auditiva/etiologia , Feminino , Células Ciliadas Auditivas/patologia , Idoso , Degeneração Neural , Pessoa de Meia-Idade , Osso Temporal/patologia , Osso Temporal/cirurgia
14.
Qual Life Res ; 33(7): 2011-2023, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38769210

RESUMO

PURPOSE: This study aimed to develop and psychometrically evaluate a patient-reported outcome measure (PROM), SAlivary, LAcrimal, NaSal (SALANS), to document patients' symptoms after radioactive iodine (RAI) treatment for differentiated thyroid cancer (DTC). METHODS: We generated and iteratively revised SALANS items based on expert input, focus group discussions and feedback from cognitive testing (n = 17). We administered an initial SALANS measure with 39 items to patients diagnosed with DTC in the past two years (n = 105). Exploratory factor analysis (EFA) examined the factor structure of the SALANS items. We assessed the consistency reliability and related the total and subscale scores of the final SALANS to existing PROMs to assess validity. RESULTS: The final SALANS consisted of 33 items and six subscales (sialadenitis, taste, xerostomia, dry eyes, epiphora, and nasal) with six factors extracted by EFA. The six subscales demonstrated good internal reliability (α range = 0.87-0.92). The SALANS total score showed good convergent validity with the Xerostomia Inventory (r = 0.86) and good discriminant validity with a measure of spirituality (r = - 0.05). The mean SALANS total score was significantly higher (d = 0.5, p < 0.04) among patients who had RAI compared to those who did not have RAI. CONCLUSION: Preliminary evidence suggests that SALANS is a novel and reliable PROM to assess the type and frequency all symptoms experienced after RAI treatment for DTC. Future work is needed to further validate and develop the scale.


Assuntos
Radioisótopos do Iodo , Medidas de Resultados Relatados pelo Paciente , Psicometria , Neoplasias da Glândula Tireoide , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Radioisótopos do Iodo/uso terapêutico , Radioisótopos do Iodo/efeitos adversos , Reprodutibilidade dos Testes , Adulto , Neoplasias da Glândula Tireoide/radioterapia , Neoplasias da Glândula Tireoide/psicologia , Idoso , Inquéritos e Questionários , Análise Fatorial , Qualidade de Vida , Xerostomia/etiologia , Xerostomia/psicologia
15.
Int J Tryptophan Res ; 17: 11786469241248287, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38757094

RESUMO

Stem cells are ubiquitously found in various tissues and organs in the body, and underpin the body's ability to repair itself following injury or disease initiation, though repair can sometimes be compromised. Understanding how stem cells are produced, and functional signaling systems between different niches is critical to understanding the potential use of stem cells in regenerative medicine. In this context, this review considers kynurenine pathway (KP) metabolism in multipotent adult progenitor cells, embryonic, haematopoietic, neural, cancer, cardiac and induced pluripotent stem cells, endothelial progenitor cells, and mesenchymal stromal cells. The KP is the major enzymatic pathway for sequentially catabolising the essential amino acid tryptophan (TRP), resulting in key metabolites including kynurenine, kynurenic acid, and quinolinic acid (QUIN). QUIN metabolism transitions into the adjoining de novo pathway for nicotinamide adenine dinucleotide (NAD) production, a critical cofactor in many fundamental cellular biochemical pathways. How stem cells uptake and utilise TRP varies between different species and stem cell types, because of their expression of transporters and responses to inflammatory cytokines. Several KP metabolites are physiologically active, with either beneficial or detrimental outcomes, and evidence of this is presented relating to several stem cell types, which is important as they may exert a significant impact on surrounding differentiated cells, particularly if they metabolise or secrete metabolites differently. Interferon-gamma (IFN-γ) in mesenchymal stromal cells, for instance, highly upregulates rate-limiting enzyme indoleamine-2,3-dioxygenase (IDO-1), initiating TRP depletion and production of metabolites including kynurenine/kynurenic acid, known agonists of the Aryl hydrocarbon receptor (AhR) transcription factor. AhR transcriptionally regulates an immunosuppressive phenotype, making them attractive for regenerative therapy. We also draw attention to important gaps in knowledge for future studies, which will underpin future application for stem cell-based cellular therapies or optimising drugs which can modulate the KP in innate stem cell populations, for disease treatment.

16.
ISME Commun ; 4(1): ycae068, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38800124

RESUMO

Particulate carbon (C) degradation in soils is a critical process in the global C cycle governing greenhouse gas fluxes and C storage. Millimeter-scale soil aggregates impose strong controls on particulate C degradation by inducing chemical gradients of e.g. oxygen, as well as limiting microbial mobility in pore structures. To date, experimental models of soil aggregates have incorporated porosity and chemical gradients but not particulate C. Here, we demonstrate a proof-of-concept encapsulating microbial cells and particulate C substrates in hydrogel matrices as a novel experimental model for soil aggregates. Ruminiclostridium cellulolyticum was co-encapsulated with cellulose in millimeter-scale polyethyleneglycol-dimethacrylate (PEGDMA) hydrogel beads. Microbial activity was delayed in hydrogel-encapsulated conditions, with cellulose degradation and fermentation activity being observed after 13 days of incubation. Unexpectedly, hydrogel encapsulation shifted product formation of R. cellulolyticum from an ethanol-lactate-acetate mixture to an acetate-dominated product profile. Fluorescence microscopy enabled simultaneous visualization of the PEGDMA matrix, cellulose particles, and individual cells in the matrix, demonstrating growth on cellulose particles during incubation. Together, these microbe-cellulose-PEGDMA hydrogels present a novel, reproducible experimental soil surrogate to connect single cells to process outcomes at the scale of soil aggregates and ecosystems.

17.
Front Cell Infect Microbiol ; 14: 1334224, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38698905

RESUMO

Aggregatibacter actinomycetemcomitans cytolethal distending toxin (Cdt) is capable of intoxicating lymphocytes macrophages, mast cells and epithelial cells. Following Cdt binding to cholesterol, in the region of membrane lipid rafts, the CdtB and CdtC subunits are internalized and traffic to intracellular compartments. These events are dependent upon, cellugyrin, a critical component of synaptic like microvesicles (SLMVCg+). Target cells, such as Jurkat cells, rendered unable to express cellugyrin are resistant to Cdt-induced toxicity. Similar to Cdt, SARS-CoV-2 entry into host cells is initiated by binding to cell surface receptors, ACE-2, also associated with cholesterol-rich lipid rafts; this association leads to fusion and/or endocytosis of viral and host cell membranes and intracellular trafficking. The similarity in internalization pathways for both Cdt and SARS-CoV-2 led us to consider the possibility that cellugyrin was a critical component in both processes. Cellugyrin deficient Calu-3 cells (Calu-3Cg-) were prepared using Lentiviral particles containing shRNA; these cells were resistant to infection by VSV/SARS-CoV-2-spike pseudotype virus and partially resistant to VSV/VSV-G pseudotype virus. Synthetic peptides representing various regions of the cellugyrin protein were prepared and assessed for their ability to bind to Cdt subunits using surface plasmon resonance. Cdt was capable of binding to a region designated the middle outer loop (MOL) which corresponds to a region extending into the cytoplasmic surface of the SLMVCg+. SARS-CoV-2 spike proteins were assessed for their ability to bind to cellugyrin peptides; SARS-CoV-2 full length spike protein preferentially binds to a region within the SLMVCg+ lumen, designated intraluminal loop 1A. SARS-CoV-2-spike protein domain S1, which contains the receptor binding domains, binds to cellugyrin N-terminus which extends out from the cytoplasmic surface of SLMV. Binding specificity was further analyzed using cellugyrin scrambled peptide mutants. We propose that SLMVCg+ represent a component of a common pathway that facilitates pathogen and/or pathogen-derived toxins to gain host cell entry.


Assuntos
Toxinas Bacterianas , SARS-CoV-2 , Sinaptogirinas , Internalização do Vírus , Humanos , Toxinas Bacterianas/metabolismo , Toxinas Bacterianas/genética , SARS-CoV-2/metabolismo , SARS-CoV-2/genética , Sinaptogirinas/metabolismo , COVID-19/metabolismo , COVID-19/virologia , Células Jurkat , Aggregatibacter actinomycetemcomitans/metabolismo , Aggregatibacter actinomycetemcomitans/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Endocitose , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Microdomínios da Membrana/metabolismo
18.
Infection ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802702

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the highly contagious respiratory disease Corona Virus Disease 2019 (COVID-19) that may lead to various neurological and psychological disorders that can be acute, lasting days to weeks or months and possibly longer. The latter is known as long-COVID or more recently post-acute sequelae of COVID (PASC). During acute COVID-19 infection, a strong inflammatory response, known as the cytokine storm, occurs in some patients. The levels of interferon-γ (IFN-γ), interferon-ß (IFN-ß), interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-α) are particularly increased. These cytokines are known to activate the enzyme indoleamine 2,3-dioxygenase 1 (IDO-1), catalysing the first step of tryptophan (Trp) catabolism through the kynurenine pathway (KP) leading to the production of several neurotoxic and immunosuppressive metabolites. There is already data showing elevation in KP metabolites both acutely and in PASC, especially regarding cognitive impairment. Thus, it is likely that KP involvement is significant in SARS-CoV-2 pathogenesis especially neurologically.

20.
West J Emerg Med ; 25(2): 264-267, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38596928

RESUMO

Introduction: The use of a reliable scoring system for quality assessment (QA) is imperative to limit inconsistencies in measuring ultrasound acquisition skills. The current grading scale used for QA endorsed by the American College of Emergency Physicians (ACEP) is non-specific, applies irrespective of the type of study performed, and has not been rigorously validated. Our goal in this study was to determine whether a succinct, organ-specific grading scale designed for lung-specific QA would be more precise with better interobserver agreement. Methods: This was a prospective validation study of an objective QA scale for lung ultrasound (LUS) in the emergency department. We identified the first 100 LUS performed in normal clinical practice in the year 2020. Four reviewers at an urban academic center who were either emergency ultrasound fellowship-trained or current fellows with at least six months of QA experience scored each study, resulting in a total of 400. The primary outcome was the level of agreement between the reviewers. Our secondary outcome was the variability of the scores given to the studies. For the agreement between reviewers, we computed the intraclass correlation coefficient (ICC) based on a two-way random-effect model with a single rater for each grading scale. We generated 10,000 bootstrapped ICCs to construct 95% confidence intervals (CI) for both grading systems. A two-sided one-sample t-test was used to determine whether there were differences in the bootstrapped ICCs between the two grading systems. Results: The ICC between reviewers was 0.552 (95% CI 0.40-0.68) for the ACEP grading scale and 0.703 (95% CI 0.59-0.79) for the novel grading scale (P < 0.001), indicating significantly more interobserver agreement using the novel scale compared to the ACEP scale. The variance of scores was similar (0.93 and 0.92 for the novel and ACEP scales, respectively). Conclusion: We found an increased interobserver agreement between reviewers when using the novel, organ-specific scale when compared with the ACEP grading scale. Increased consistency in feedback based on objective criteria directed to the specific, targeted organ provides an opportunity to enhance learner education and satisfaction with their ultrasound education.


Assuntos
Serviço Hospitalar de Emergência , Pulmão , Humanos , Pulmão/diagnóstico por imagem , Estudos Prospectivos , Ultrassonografia , Escolaridade , Variações Dependentes do Observador , Reprodutibilidade dos Testes
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