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1.
Anim Microbiome ; 6(1): 55, 2024 Oct 08.
Article de Anglais | MEDLINE | ID: mdl-39380028

RÉSUMÉ

Animal guts contain numerous microbes, which are critical for nutrient assimilation and pathogen defence. While corals and other Cnidaria lack a true differentiated gut, they possess semi-enclosed gastrovascular cavities (GVCs), where vital processes such as digestion, reproduction and symbiotic exchanges take place. The microbiome harboured in GVCs is therefore likely key to holobiont fitness, but remains severely understudied due to challenges of working in these small compartments. Here, we developed minimally invasive methodologies to sample the GVC of coral polyps and characterise the microbial communities harboured within. We used glass capillaries, low dead volume microneedles, or nylon microswabs to sample the gastrovascular microbiome of individual polyps from six species of corals, then applied low-input DNA extraction to characterise the microbial communities from these microliter volume samples. Microsensor measurements of GVCs revealed anoxic or hypoxic micro-niches, which persist even under prolonged illumination with saturating irradiance. These niches harboured microbial communities enriched in putatively microaerophilic or facultatively anaerobic taxa, such as Epsilonproteobacteria. Some core taxa found in the GVC of Lobophyllia hemprichii from the Great Barrier Reef were also detected in conspecific colonies held in aquaria, indicating that these associations are unlikely to be transient. Our findings suggest that the coral GVC is chemically and microbiologically similar to the gut of higher Metazoa. Given the importance of gut microbiomes in mediating animal health, harnessing the coral "gut microbiome" may foster novel active interventions aimed at increasing the resilience of coral reefs to the climate crisis.

2.
Proc Natl Acad Sci U S A ; 121(42): e2323052121, 2024 Oct 15.
Article de Anglais | MEDLINE | ID: mdl-39378095

RÉSUMÉ

Cardiac myosin-specific (MyHC) T cells drive the disease pathogenesis of immune checkpoint inhibitor-associated myocarditis (ICI-myocarditis). To determine whether MyHC T cells are tissue-resident memory T (TRM) cells, we characterized cardiac TRM cells in naive mice and established that they have a distinct phenotypic and transcriptional profile that can be defined by their upregulation of CD69, PD-1, and CXCR6. We then investigated the effects of cardiac injury through a modified experimental autoimmune myocarditis mouse model and an ischemia-reperfusion injury mouse model and determined that cardiac inflammation induces the recruitment of autoreactive MyHC TRM cells, which coexpress PD-1 and CD69. To investigate whether the recruited MyHC TRM cells could increase susceptibility to ICI-myocarditis, we developed a two-hit ICI-myocarditis mouse model where cardiac injury was induced, mice were allowed to recover, and then were treated with anti-PD-1 antibodies. We determined that mice who recover from cardiac injury are more susceptible to ICI-myocarditis development. We found that murine and human TRM cells share a similar location in the heart and aggregate along the perimyocardium. We phenotyped cells obtained from pericardial fluid from patients diagnosed with dilated cardiomyopathy and ischemic cardiomyopathy and established that pericardial T cells are predominantly CD69+ TRM cells that up-regulate PD-1. Finally, we determined that human pericardial macrophages produce IL-15, which supports and maintains pericardial TRM cells.


Sujet(s)
Inhibiteurs de points de contrôle immunitaires , Cellules T mémoire , Myocardite , Animaux , Myocardite/immunologie , Myocardite/anatomopathologie , Myocardite/métabolisme , Inhibiteurs de points de contrôle immunitaires/pharmacologie , Souris , Humains , Cellules T mémoire/immunologie , Cellules T mémoire/métabolisme , Modèles animaux de maladie humaine , Mâle , Récepteur-1 de mort cellulaire programmée/métabolisme , Myosines cardiaques/immunologie , Myosines cardiaques/métabolisme , Antigènes de différenciation des lymphocytes T/métabolisme , Antigènes de différenciation des lymphocytes T/immunologie , Souris de lignée C57BL , Lectines de type C/métabolisme , Femelle , Myosines/métabolisme , Myocarde/immunologie , Myocarde/anatomopathologie , Myocarde/métabolisme , Antigènes CD
3.
Eur J Immunol ; : e2451325, 2024 Oct 04.
Article de Anglais | MEDLINE | ID: mdl-39367550

RÉSUMÉ

Interferons (IFNs) are a critical component of innate immune defenses and limit viral disease severity. To advance studies on IFNs and their neutralization by pathogenic autoantibodies, we generated a Renilla luciferase-based reporter cell line capable of detecting the activities of IFN-Is, IFN-II, and IFN-IIIs. The reporter cell line exhibits a 125- to 2000-fold higher sensitivity to IFNs than a commonly used alternative biological reporter system and allows for a rapid and simple live-cell workflow for detecting low titer amounts of neutralizing anti-IFN antibodies.

4.
Sci Rep ; 14(1): 21826, 2024 09 18.
Article de Anglais | MEDLINE | ID: mdl-39294209

RÉSUMÉ

Organismal phenotyping to identify fitness traits is transforming our understanding of adaptive responses and ecological interactions of species within changing environments. Here we present a portable Multi-Taxa Phenotyping (MTP) system that can retrieve a suite of metabolic and photophysiological parameter across light, temperature, and/or chemical gradients, using real time bio-optical (oxygen and chlorophyll a fluorescence) measurements. The MTP system integrates three well-established technologies for the first time: an imaging Pulse Amplitude Modulated (PAM) chlorophyll a fluorometer, custom-designed well plates equipped with optical oxygen sensors, and a thermocycler. We demonstrate the ability of the MTP system to distinguish phenotypic performance characteristics of diverse aquatic taxa spanning corals, mangroves and algae based on metabolic parameters and Photosystem II dynamics, in a high-throughput capacity and accounting for interactions of different environmental gradients on performance. Extracted metrics from the MTP system can not only provide information on the performance of aquatic taxa exposed to differing environmental gradients, but also provide predicted phenotypic responses of key aquatic organisms to environmental change. Further work validating how rapid phenotyping tools such as the MTP system predict phenotypic responses to long term environmental changes in situ are urgently required to best inform how these tools can support management efforts.


Sujet(s)
Phénotype , Animaux , Chlorophylle A/métabolisme , Organismes aquatiques/physiologie , Anthozoa/physiologie , Oxygène/métabolisme , Chlorophylle/métabolisme , Complexe protéique du photosystème II/métabolisme
5.
Clin Transl Radiat Oncol ; 49: 100851, 2024 Nov.
Article de Anglais | MEDLINE | ID: mdl-39308635

RÉSUMÉ

Background and purpose: Radical surgery is the standard of care for early rectal cancer. However, alternative organ-preserving approaches are attractive, especially in frail or elderly patients as these avoid surgical complications. We have assessed the efficacy of sole Contact X-ray Brachytherapy (CXB) treatment in stage-1 rectal cancer patients who were unsuitable for or declined surgery. Materials and methods: This retrospective multi-centre study (2009-2021) evaluated 76 patients with T1/2-N0-M0 rectal adenocarcinomas who were treated with CXB alone. Outcomes were assessed for the entire cohort and sub-groups based on the T-stage and the criteria for receiving CXB alone; Group A: patients who were fit enough for surgery but declined, Group B: patients who were high-risk for surgery and Group C: patients who had received prior pelvic radiation for a different cancer. Results: With a median follow-up of 26(IQR:12-49) months, initial clinical Complete Response (cCR) was 82(70-93)% with rates of local regrowth 18(8-29)%, 3-year actuarial local control (LC) 84(75-95)%, distant relapse 3 %, and no nodal relapse. 5-year disease-free survival (DFS) and overall survival (OS) were 66(48-78)% and 58(44-75)%. Lower OS was observed in Groups B [HR:2.54(95 %CI:1.17, 5.59), p = 0.02] and C [HR:2.75(95 %CI:1.15, 6.58), p = 0.03]. Previous pelvic radiation predicted lower cCR and OS. The main toxicity was G1-2 rectal bleeding (26 %) and symptoms of impaired anal sphincter function were not reported in any patients. Conclusion: CXB treatment alone achieved a high cCR rate with satisfactory LC and DFS. Inferior oncological outcomes were observed in patients who had received prior pelvic radiotherapy. CXB alone, with its favourable toxicity profile and avoidance of general anaesthesia and surgery risks, therefore, can be considered for patients who are unsuitable for or refuse surgery.

6.
Clin Obes ; : e12703, 2024 Sep 17.
Article de Anglais | MEDLINE | ID: mdl-39287006

RÉSUMÉ

Resting energy expenditure (REE) and metabolic fuel utilization (carbohydrate or fat) proxied by respiratory quotient (RQ) from indirect calorimetry enables more precise measurement of energy needs and fat oxidation capacity. The study compared the effectiveness of providing energy expenditure information during diet and exercise weight intervention versus standard of care (SOC) on weight loss outcomes. Fifty-two participants with obesity were recruited from a specialist weight loss service, randomized 1:1 to intervention (INT) or SOC only. Participants in INT received four-weekly dietetic counselling, using biofeedback from energy expenditure data to recommend caloric restriction and physical activity goals, in addition to SOC. The primary outcome was the mean difference in weight loss between both groups after 24 weeks. Secondary outcomes include participant acceptability and tolerability using indirect calorimetry. Participants in the INT group demonstrated additional weight loss (-2.3 kg [95% CI: -3.1, -1.5]; p <.001), reduced waist circumference (-3.9 cm [95% CI: -5.48, -2.26]; p <.001), and decreased body fat percentage (-1.5% [95% CI:-2.31, -0.72], p <.001), compared to SOC, after adjusting for baseline body mass index, age, and sex. Forty-two percent (10/24) of participants in INT group achieved the minimum clinically significant threshold of 5% weight loss from baseline, compared to 8% (2/26) in the SOC group (p = .007). Participant acceptability and tolerability of indirect calorimetry were high, with mean scores of 4.5 ± 0.6 and 4.2 ± 0.7 (5-point Likert scale). The study establishes the safety and practical integration of biofeedback using indirect calorimetry promoting improved self-regulation and enhancing weight loss.

7.
BMC Surg ; 24(1): 257, 2024 Sep 11.
Article de Anglais | MEDLINE | ID: mdl-39261888

RÉSUMÉ

BACKGROUND: Workplace-based assessment (WBA) can facilitate evaluation of operative performance; however, implementation of WBA is sometimes unsuccessful. The American Board of Surgery Entrustable Professional Activities WBA project was launched in July 2023. Some programs will face the challenge of re-implementation of a WBA following previous failures. It is unknown what interventions are most effective for WBA re-implementation. Our goal is to identify barriers and facilitators to re-implementing SIMPL, an operative performance WBA. METHODS: The System for Improving and Measuring Procedural Learning (SIMPL) was implemented at our residency in 2018, but usage rates were low. We interviewed residents and faculty to identify barriers to usage and opportunities for improvement. Residents reported that SIMPL usage declined because of several factors, including a low faculty response rate, while some faculty reported not responding because they were unable to login to the app and because usage was not mandated. We then re-implemented SIMPL using a plan based on Kotter's Model of Change. To evaluate impact, we analyzed rates of SIMPL usage when it was first implemented, as well as before and after the date of re-implementation. RESULTS: In September 2022, we re-implemented SIMPL at our program with measures addressing the identified barriers. We found that, in the six months after re-implementation, an average of 145.8 evaluations were submitted by residents per month, compared with 47 evaluations per month at the start of the original implementation and 5.8 evaluations per month just prior to re-implementation. Faculty completed 60.6% of evaluations and dictated feedback for 59.1% of these evaluations, compared with 69.1% at implementation (44% dictated) and 43% prior to re-implementation (53% dictated). CONCLUSIONS: After identifying barriers to implementation of a WBA, we re-implemented it with significantly higher usage by faculty and residents. Future opportunities exist to implement or re-implement assessment tools within general surgery programs. These opportunities may have a significant impact in the setting of national standardization of workplace-based assessment among general surgery residencies.


Sujet(s)
Compétence clinique , Chirurgie générale , Internat et résidence , Chirurgie générale/enseignement et éducation , Humains , Évaluation des acquis scolaires , Lieu de travail , Enseignement spécialisé en médecine/méthodes
8.
Acad Med ; 2024 Sep 16.
Article de Anglais | MEDLINE | ID: mdl-39283809

RÉSUMÉ

PURPOSE: Cross-cover care (care for hospitalized patients when the primary team is absent) is a common graduate medical education responsibility; however, it may lead to increased preventable adverse events. Despite understanding the difficulties of cross-cover care, medical educators lack comprehensive knowledge of specific challenges that residents face and how they handle these challenges. This study explores the challenges residents experience when providing cross-cover care. METHOD: The authors conducted 60 semistructured, qualitative interviews with 20 internal medicine and surgery residents at a single academic institution between October 2021 and April 2022. Each resident participated in 3 interviews, 2 immediately after a shift. Working inductively, the authors generated codes for important themes. Study design and data collection were guided by interpretive description, a qualitative approach for health care research focused on experiences and perceptions to develop meaningful findings. To illustrate residents' workflow and aid in quality improvement efforts, the authors created a process map. RESULTS: Seventeen cross-cover challenges were organized into 7 interrelated and overlapping themes: lack of baseline knowledge, inadequate or inaccurate information transfer from the primary team, unfamiliarity with cross-cover patients, high task volume leading to increased interruptions, ill-defined roles leading to unmet expectations from others, perceived decreased access to resources, and fatigue. The process map illustrates 4 cross-cover workflow components: information transfer from the primary team to the cross-cover team, direct handling of cross-cover tasks that are assigned by the primary team or that arise during the time of cross-cover, information transfer back to primary team and other care team members, and responsibilities that residents have overnight that are not directly related to cross-cover. CONCLUSIONS: Residents face substantial challenges when providing cross-cover care, which have important implications for patient safety and resident well-being. The medical community should strive to develop educational and structural interventions to improve this process.

9.
Article de Anglais | MEDLINE | ID: mdl-39191435

RÉSUMÉ

BACKGROUND AND AIM: This study aimed to compare the determinants and impact of hepatocellular carcinoma (HCC) surveillance rates for people with metabolic dysfunction-associated steatotic liver disease (MASLD) versus other chronic liver diseases. METHODS: A dataset of HCC patients from a UK hospital (2007-2022) was analyzed. The Mann-Whitney U-test compared continuous variables. The χ2 and two-tailed Fisher exact tests compared categorical data. Regression modeling analyzed the impact of MASLD on the size and number of HCC nodules and curative treatment. The Cox proportional hazards model assessed the influence of MASLD on overall survival. RESULTS: A total of 176 of 687 (25.6%) HCC patients had MASLD. Fewer people with MASLD HCC were enrolled in HCC surveillance compared to non-MASLD HCC (38 [21.6%] vs 215 [42.1%], P < 0.001). Patients with MASLD HCC were less likely to have been under secondary care (n = 57 [32.4%] vs 259 [50.7%], P < 0.001) and less likely to have cirrhosis (n = 113 [64.2%] vs 417 [81.6%], P < 0.001). MASLD was associated with a 12.3-mm (95% confidence interval [CI] 10.8-14.0 mm) greater tumor diameter compared to people without MASLD (P = 0.002). Patients with MASLD HCC had 0.62 reduced odds (95% CI 0.43-0.91) of receiving curative treatment compared to non-MASLD HCC (P = 0.014). Overall survival was similar for patients with MASLD HCC versus non-MASLD HCC (hazard ratio 1.03, 95% CI 0.85-1.25, P = 0.748). CONCLUSION: Patients with MASLD are less likely to have been enrolled in HCC surveillance due to undiagnosed cirrhosis or presenting with non-cirrhotic HCC. Patients with MASLD HCC present with larger tumors and are less likely to receive curative treatment.

10.
J Antimicrob Chemother ; 79(9): 2317-2326, 2024 Sep 03.
Article de Anglais | MEDLINE | ID: mdl-39051678

RÉSUMÉ

BACKGROUND: Estimates of the prevalence of antimicrobial resistance (AMR) underpin effective antimicrobial stewardship, infection prevention and control, and optimal deployment of antimicrobial agents. Typically, the prevalence of AMR is determined from real-world antimicrobial susceptibility data that are time delimited, sparse, and often biased, potentially resulting in harmful and wasteful decision-making. Frequentist methods are resource intensive because they rely on large datasets. OBJECTIVES: To determine whether a Bayesian approach could present a more reliable and more resource-efficient way to estimate population prevalence of AMR than traditional frequentist methods. METHODS: Retrospectively collected, open-source, real-world pseudonymized healthcare data were used to develop a Bayesian approach for estimating the prevalence of AMR by combination with prior AMR information from a contextualized review of literature. Iterative random sampling and cross-validation were used to assess the predictive accuracy and potential resource efficiency of the Bayesian approach compared with a standard frequentist approach. RESULTS: Bayesian estimation of AMR prevalence made fewer extreme estimation errors than a frequentist estimation approach [n = 74 (6.4%) versus n = 136 (11.8%)] and required fewer observed antimicrobial susceptibility results per pathogen on average [mean = 28.8 (SD = 22.1) versus mean = 34.4 (SD = 30.1)] to avoid any extreme estimation errors in 50 iterations of the cross-validation. The Bayesian approach was maximally effective and efficient for drug-pathogen combinations where the actual prevalence of resistance was not close to 0% or 100%. CONCLUSIONS: Bayesian estimation of the prevalence of AMR could provide a simple, resource-efficient approach to better inform population infection management where uncertainty about AMR prevalence is high.


Sujet(s)
Théorème de Bayes , Résistance bactérienne aux médicaments , Humains , Prévalence , Études rétrospectives , Antibactériens/pharmacologie , Modèles théoriques , Tests de sensibilité microbienne , Gestion responsable des antimicrobiens
11.
Radiother Oncol ; 199: 110465, 2024 10.
Article de Anglais | MEDLINE | ID: mdl-39074538

RÉSUMÉ

BACKGROUND AND PURPOSE: External Beam Radiotherapy (EBRT) followed by Contact X-ray Brachytherapy (CXB) and vice versa are viable alternatives to surgery for selected rectal cancer patients who have small tumours (≤3 cm). However, the optimal sequence of treatment needs to be established. We compared two approaches using Propensity Score (PS) matching and inverse probability treatment weighting (IPTW) analyses to investigate whether the sequence of treatment affected patient outcomes. MATERIALS AND METHODS: This retrospective analysis (2008-2019) included patients with rectal adenocarcinoma (cT1-3,N0-1,M0, grade 1-2, size ≤ 3 cm) who received both EBRT and CXB, irrespective of treatment sequence. PS matching and IPTW were conducted to balance covariate standardised mean differences between groups. Oncological outcomes and rate of post-treatment rectal bleeding were assessed. RESULTS: Following PS matching and IPTW analyses from 251 eligible patients; 103 starting with EBRT (median follow-up: 37 [IQR:18-56] months) and 148 with CXB (median follow-up: 32 [IQR:16-54] months, a significant improvement in 3-year overall survival (77% vs 85%, p = 0.02, [HR:0.58 (95% CI:0.37-0.91)]) and a higher risk of post-treatment rectal bleeding (grade 1 (26%) and grade 2 (6%)) were found in patients who started with CXB (p = 0.08). No significant differences were observed in local regrowth (18% vs 12%, p = 0.47), distant relapse (10% vs 6%, p = 0.53), 3-year organ preservation rates (70% vs 75%, p = 0.20, [HR:0.66 (95% CI: 0.35-1.26)]), or disease-free survival (78% vs 82%, p = 0.17, [HR: 0.47 (95% CI: 0.16-1.38)]) CONCLUSION: In patients with rectal cancer (≤3 cm), commencing with CXB rather than EBRT, was associated with improved overall survival, but had a higher risk of G1/2 rectal bleeding. No statistically significant differences were observed in other oncological outcomes.


Sujet(s)
Curiethérapie , Traitements préservant les organes , Tumeurs du rectum , Humains , Tumeurs du rectum/radiothérapie , Tumeurs du rectum/anatomopathologie , Tumeurs du rectum/mortalité , Mâle , Femelle , Études rétrospectives , Sujet âgé , Curiethérapie/méthodes , Curiethérapie/effets indésirables , Adulte d'âge moyen , Traitements préservant les organes/méthodes , Adénocarcinome/radiothérapie , Adénocarcinome/anatomopathologie , Adénocarcinome/mortalité , Score de propension , Sujet âgé de 80 ans ou plus
12.
J Hum Nutr Diet ; 37(5): 1255-1264, 2024 Oct.
Article de Anglais | MEDLINE | ID: mdl-38990157

RÉSUMÉ

BACKGROUND: The COVID-19 pandemic put unprecedented pressure on weight management services. These services were required to adapt to continue to provide care for people living with obesity. This study sought to develop consensus recommendations on the best practice solutions adopted by weight management services in the United Kingdom during the COVID-19 pandemic. METHODS: This study utilised a semi-structured interview and a modified Delphi methodology to develop a consensus of best practice recommendations identified by specialist weight management services during the pandemic. RESULTS: Twenty-three healthcare professionals working in weight management service across the United Kingdom participated in the study. Analysis of interview transcripts identified four key thematic domains: outpatient, patient education and support, perioperative care and team working. Of the initial 43 unique recommendations, 30 reached consensus agreement. Outpatient recommendations focused on communication strategies, patient self-monitoring and remote patient tracking. Patient education and support recommendations addressed the development of online educational resources and support groups. Perioperative care recommendations emphasised case prioritisation, waiting list support and postoperative care. Team working recommendations targeted the use of digital collaboration tools and strategies for effective teamwork. CONCLUSION: Developing consensus recommendations on best practice is a critical step for weight management and outpatient services to achieve higher standards of care. These recommendations provide a springboard for departmental discussions, paving the way for improved experiences for individuals living with obesity as they progress along their weight management journey.


Sujet(s)
COVID-19 , Consensus , Obésité , SARS-CoV-2 , Humains , COVID-19/thérapie , Royaume-Uni , Obésité/thérapie , Méthode Delphi , Soins ambulatoires/normes , Soins ambulatoires/organisation et administration , Guides de bonnes pratiques cliniques comme sujet , Pandémies , Éducation du patient comme sujet
13.
Int J Cancer ; 155(11): 1982-1995, 2024 Dec 01.
Article de Anglais | MEDLINE | ID: mdl-39057841

RÉSUMÉ

Advanced glycation end-products (AGEs), formed endogenously or obtained exogenously from diet, may contribute to chronic inflammation, intracellular signaling alterations, and pathogenesis of several chronic diseases including colorectal cancer (CRC). However, the role of AGEs in CRC survival is less known. The associations of pre-diagnostic circulating AGEs and their soluble receptor (sRAGE) with CRC-specific and overall mortality were estimated using multivariable-adjusted Cox proportional hazards regression among 1369 CRC cases in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Concentrations of major plasma AGEs, Nε-[carboxy-methyl]lysine (CML), Nε-[carboxy-ethyl]lysine (CEL) and Nδ-[5-hydro-5-methyl-4-imidazolon-2-yl]-ornithine (MG-H1), were measured using ultra-performance liquid chromatography mass-spectrometry. sRAGE was assessed by enzyme-linked immunosorbent assay. Over a mean follow-up period of 96 months, 693 deaths occurred of which 541 were due to CRC. Individual and combined AGEs were not statistically significantly associated with CRC-specific or overall mortality. However, there was a possible interaction by sex for CEL (Pinteraction = .05). Participants with higher sRAGE had a higher risk of dying from CRC (HRQ5vs.Q1 = 1.67, 95% CI: 1.21-2.30, Ptrend = .02) or any cause (HRQ5vs.Q1 = 1.38, 95% CI: 1.05-1.83, Ptrend = .09). These associations tended to be stronger among cases with diabetes (Pinteraction = .03) and pre-diabetes (Pinteraction <.01) before CRC diagnosis. Pre-diagnostic AGEs were not associated with CRC-specific and overall mortality in individuals with CRC. However, a positive association was observed for sRAGE. Our findings may stimulate further research on the role of AGEs and sRAGE in survival among cancer patients with special emphasis on potential effect modifications by sex and diabetes.


Sujet(s)
Tumeurs colorectales , Produits terminaux de glycation avancée , Récepteur spécifique des produits finaux de glycosylation avancée , Humains , Tumeurs colorectales/sang , Tumeurs colorectales/mortalité , Tumeurs colorectales/diagnostic , Mâle , Femelle , Produits terminaux de glycation avancée/sang , Adulte d'âge moyen , Récepteur spécifique des produits finaux de glycosylation avancée/sang , Sujet âgé , Études prospectives , Lysine/sang , Lysine/analogues et dérivés , Ornithine/sang , Ornithine/analogues et dérivés , Modèles des risques proportionnels , Marqueurs biologiques tumoraux/sang , Imidazoles
14.
Sci Signal ; 17(845): eadg4124, 2024 07 16.
Article de Anglais | MEDLINE | ID: mdl-39012937

RÉSUMÉ

Kaposi's sarcoma-associated herpesvirus (KSHV) is an oncogenic herpesvirus that is linked directly to the development of Kaposi's sarcoma. KSHV establishes a latent infection in B cells, which can be reactivated to initiate lytic replication, producing infectious virions. Using pharmacological and genetic silencing approaches, we showed that the voltage-gated K+ channel Kv1.3 in B cells enhanced KSHV lytic replication. The KSHV replication and transcription activator (RTA) protein increased the abundance of Kv1.3 and led to enhanced K+ channel activity and hyperpolarization of the B cell membrane. Enhanced Kv1.3 activity promoted intracellular Ca2+ influx, leading to the Ca2+-driven nuclear localization of KSHV RTA and host nuclear factor of activated T cells (NFAT) proteins and subsequently increased the expression of NFAT1 target genes. KSHV lytic replication and infectious virion production were inhibited by Kv1.3 blockers or silencing. These findings highlight Kv1.3 as a druggable host factor that is key to the successful completion of KSHV lytic replication.


Sujet(s)
Herpèsvirus humain de type 8 , Canal potassique Kv1.3 , Facteurs de transcription NFATC , Réplication virale , Herpèsvirus humain de type 8/physiologie , Herpèsvirus humain de type 8/génétique , Herpèsvirus humain de type 8/métabolisme , Humains , Canal potassique Kv1.3/métabolisme , Canal potassique Kv1.3/génétique , Canal potassique Kv1.3/antagonistes et inhibiteurs , Facteurs de transcription NFATC/métabolisme , Facteurs de transcription NFATC/génétique , Protéines précoces immédiates/métabolisme , Protéines précoces immédiates/génétique , Transactivateurs/métabolisme , Transactivateurs/génétique , Lymphocytes B/virologie , Lymphocytes B/métabolisme , Calcium/métabolisme , Sarcome de Kaposi/virologie , Sarcome de Kaposi/métabolisme , Sarcome de Kaposi/génétique
16.
iScience ; 27(7): 110244, 2024 Jul 19.
Article de Anglais | MEDLINE | ID: mdl-39040070

RÉSUMÉ

Prior research has suggested that GATA6+ pericardial macrophages may traffic to the myocardium to prevent interstitial fibrosis after myocardial infarction (MI), while subsequent literature claims that they do not. We demonstrate that GATA6+ pericardial macrophages are critical for preventing IL-33 induced pericarditis and attenuate trafficking of inflammatory monocytes and granulocytes to the pericardial cavity after MI. However, absence of GATA6+ macrophages did not affect myocardial inflammation due to MI or coxsackievirus-B3 induced myocarditis, or late-stage cardiac fibrosis and cardiac function post MI. GATA6+ macrophages are significantly less transcriptionally active following stimulation in vitro compared to bone marrow-derived macrophages and do not induce upregulation of inflammatory markers in fibroblasts. This suggests that GATA6+ pericardial macrophages attenuate inflammation through their interactions with surrounding cells. We therefore conclude that GATA6+ pericardial macrophages are critical in modulating pericardial inflammation, but do not play a significant role in controlling myocardial inflammation or fibrosis.

17.
J Clin Apher ; 39(4): e22141, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-39060110

RÉSUMÉ

Modern apheresis devices, with increased procedural precision, automation, and monitoring, have been shown to allow for safe delivery of apheresis therapies in young children. Medical advances are increasing demand for apheresis procedures like mononuclear cell collection in infants <10 kg, including stem-cell supported chemotherapy, cell collection for chimeric antigen receptor T cell development, and now ex vivo gene therapies for rare genetic diseases. Nevertheless, safe delivery in small infants involves a range of unique considerations and challenges, beyond just size, and experience will vary between centers. In this case report we describe our experience performing mononuclear cell collection in our smallest patient to date and outline a practice guideline developed following a literature review and discussion with both international experts and device representatives. This case may help to inform other clinicians aiming to provide apheresis care to very small infants in their own centers.


Sujet(s)
Aphérèse , Humains , Nourrisson , Aphérèse/méthodes , Cellules souches du sang périphérique , Nouveau-né , Mâle , Guides de bonnes pratiques cliniques comme sujet
18.
Inorg Chem ; 63(29): 13525-13545, 2024 Jul 22.
Article de Anglais | MEDLINE | ID: mdl-38989543

RÉSUMÉ

A diverse family of heterobimetallic bridging hydride adducts of the type [LAu(µ-H)2MCp2][X] (L = 1,3-bis(2,6-diisopropylphenyl)imidazole-2-ylidene, IPr; 1,3-bis(1-adamantyl)imidazole-2-ylidene, IAd; 1,3-bis(2,6-di-iso-propylphenyl)-5,5-dimethyl-4,6-diketopyrimidinyl-2-ylidene, DippDAC; triphenylphosphine, PPh3; 2-di-tert-butylphosphino-2',4',6'-triisopropylbiphenyl, tBuXPhos; X = SbF6-, BF4- or TfO-) was synthesized by reacting group VI metallocene dihydrides Cp2MH2 (Cp = cyclopentadienyl anion; M = Mo, W) with cationic gold(I) complexes [LAu(NCMe)][X]. Trimetallic [L'Au2(µ-H)2WCp2][X]2 and tetrametallic [L'Au2{(µ-H)2WCp2}2] [X]2 complexes (L' = rac-2,2'-bis(diphenylphosphino)-1,1'-binaphthalene or bis(diphenylphosphinomethane)) were obtained by reacting digold [L'{Au(NCMe)}2][X]2 with Cp2WH2 in a 1:1 and a 1:2 stoichiometry. Accessing such a broad structural diversity allowed us to pinpoint roles played by the ancillary ligands and group VI metals on the bonding properties of this family of bridging hydrides. In particular, a clear effect of the ligand on the interaction energy and electronic structure was observed, with important implications on photolytic reactivity. UV or visible light irradiation, indeed, leads to the selective cleavage of the heterobimetallic Au(µ-H)2M arrangement and formation of molecular gold hydrides. The photolysis was found to be chromoselective (wavelength-dependent), which can be ascribed to different charge redistributions upon excitation to the first (Kasha's reactivity) and higher (anti-Kasha's reactivity) excited states.

19.
Cell Rep ; 43(7): 114405, 2024 Jul 23.
Article de Anglais | MEDLINE | ID: mdl-38923463

RÉSUMÉ

The RNA cap methyltransferase CMTR1 methylates the first transcribed nucleotide of RNA polymerase II transcripts, impacting gene expression mechanisms, including during innate immune responses. Using mass spectrometry, we identify a multiply phosphorylated region of CMTR1 (phospho-patch [P-Patch]), which is a substrate for the kinase CK2 (casein kinase II). CMTR1 phosphorylation alters intramolecular interactions, increases recruitment to RNA polymerase II, and promotes RNA cap methylation. P-Patch phosphorylation occurs during the G1 phase of the cell cycle, recruiting CMTR1 to RNA polymerase II during a period of rapid transcription and RNA cap formation. CMTR1 phosphorylation is required for the expression of specific RNAs, including ribosomal protein gene transcripts, and promotes cell proliferation. CMTR1 phosphorylation is also required for interferon-stimulated gene expression. The cap-snatching virus, influenza A, utilizes host CMTR1 phosphorylation to produce the caps required for virus production and infection. We present an RNA cap methylation control mechanism whereby CK2 controls CMTR1, enhancing co-transcriptional capping.


Sujet(s)
Casein Kinase II , Methyltransferases , Coiffes des ARN , Animaux , Humains , Casein Kinase II/métabolisme , Casein Kinase II/génétique , Cellules HEK293 , Virus de la grippe A , Grippe humaine/virologie , Grippe humaine/métabolisme , Grippe humaine/génétique , Méthylation , Methyltransferases/métabolisme , Phosphorylation , Coiffes des ARN/métabolisme , RNA polymerase II/métabolisme
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