56 research outputs found
In vivo imaging of microenvironmental and anti-PD-L1-mediated dynamics in cancer using S100A8/S100A9 as an imaging biomarker
Purpose: As a promotor of tumor invasion and tumor microenvironment (TME) formation, the protein complex S100A8/S100A9 is associated with poor prognosis. Our aim was to further evaluate its origin and regulatory effects, and to establish an imaging biomarker for TME activity. Methods: S100A9â/âcells (ko) were created from syngeneic murine breast cancer 4T1 (high malignancy) and 67NR (low malignancy) wildtype (wt) cell lines and implanted into either female BALB/c wildtype or S100A9â/â mice (n = 10 each). Anti-S100A9-Cy5.5-targeted fluorescence reflectance imaging was performed at 0 h and 24 h after injection. Potential early changes of S100A9-presence under immune checkpoint inhibition (anti-PD-L1, n = 7 vs. rat IgG2b as isotype control, n = 3) were evaluated. Results: In S100A9â/âmice contrast-to-noise-ratios were significantly reduced for wt and S100A9â/âtumors. No significant differences were detected for 4T1 ko and 67NR ko cells as compared to wildtype cells. Under anti-PD-L1 treatment S100A9 presence significantly decreased compared with the control group. Conclusion: Our results confirm a secretion of S100A8/S100A9 by the TME, while tumor cells do not apparently release the protein. Under immune checkpoint inhibition S100A9-imaging reports an early decrease of TME activity. Therefore, S100A9-specific imaging may serve as an imaging biomarker for TME formation and activity
Pulmonary vein reconnection and repeat ablation characteristics following cryoballoonâcompared to radiofrequencyâbased pulmonary vein isolation
Background: Despite advances in efficacy and safety of pulmonary vein isolation (PVI), atrial fibrillation (AF) recurrence after PVI remains common. PVâreconnection is the main finding during repeat PVI procedures performed to treat recurrent AF. Objective: To analyze pulmonary vein (PV) reconnection patterns during repeat ablation procedures in a large cohort of consecutive patients undergoing radio frequency or cryoballoonâbased PVI. Methods: Retrospective analysis of PVâreconnection patterns and analysis of reâablation strategies in consecutive index RFâ and CBâbased PVI and their respective reâablation procedures during concomitant usage of both energy sources at a single highâvolume center in Germany. Results: A total of 610 first (06/2015â10/2022) and 133 s (01/2016â11/2022) repeat ablation procedures after 363 (60%) RFâ and 247 (40%) CBâbased index PVIs between 01/2015 and 12/2021 were analyzed. PVâreconnection was found in 509/610 (83%) patients at first and 74/133 (56%) patients at second repeat procedure. 465 of 968 (48%) initially via CB isolated PVs were reconnected at first reâablation but 796 of 1422 initially RFâisolated PV (56%) were reconnected (OR: 0.73 [95% CI: 0.62â0.86]; p < .001). This was driven by fewer reconnections of the left PVs (LSPV: OR: 0.60 [95% CI: 0.42â0.86]; p = .005 and LSPV: 0.67 [0.47â0.95]; p = .026). PVâreconnection was more likely after longer, RFâbased index PVI and in older females. Repeat procedures were shorter after CBâcompared to after RFâPVI. Conclusions: Reconnection remains the most common reason for repeat AF ablation procedures after PVI. Our data suggest to preferentially use of the cryoballoon during index PVI, especially in older women
Pulmonary vein reconnection and repeat ablation characteristics following cryoballoonâcompared to radiofrequencyâbased pulmonary vein isolation
Background: Despite advances in efficacy and safety of pulmonary vein isolation (PVI), atrial fibrillation (AF) recurrence after PVI remains common. PVâreconnection is the main finding during repeat PVI procedures performed to treat recurrent AF. Objective: To analyze pulmonary vein (PV) reconnection patterns during repeat ablation procedures in a large cohort of consecutive patients undergoing radio frequency or cryoballoonâbased PVI. Methods: Retrospective analysis of PVâreconnection patterns and analysis of reâablation strategies in consecutive index RFâ and CBâbased PVI and their respective reâablation procedures during concomitant usage of both energy sources at a single highâvolume center in Germany. Results: A total of 610 first (06/2015â10/2022) and 133 s (01/2016â11/2022) repeat ablation procedures after 363 (60%) RFâ and 247 (40%) CBâbased index PVIs between 01/2015 and 12/2021 were analyzed. PVâreconnection was found in 509/610 (83%) patients at first and 74/133 (56%) patients at second repeat procedure. 465 of 968 (48%) initially via CB isolated PVs were reconnected at first reâablation but 796 of 1422 initially RFâisolated PV (56%) were reconnected (OR: 0.73 [95% CI: 0.62â0.86]; p < .001). This was driven by fewer reconnections of the left PVs (LSPV: OR: 0.60 [95% CI: 0.42â0.86]; p = .005 and LSPV: 0.67 [0.47â0.95]; p = .026). PVâreconnection was more likely after longer, RFâbased index PVI and in older females. Repeat procedures were shorter after CBâcompared to after RFâPVI. Conclusions: Reconnection remains the most common reason for repeat AF ablation procedures after PVI. Our data suggest to preferentially use of the cryoballoon during index PVI, especially in older women
Inherited variants in CHD3 show variable expressivity in Snijders Blok-Campeau syndrome
Purpose Common diagnostic next-generation sequencing strategies are not optimized to identify inherited variants in genes associated with dominant neurodevelopmental disorders as causal when the transmitting parent is clinically unaffected, leaving a significant number of cases with neurodevelopmental disorders undiagnosed. Methods We characterized 21 families with inherited heterozygous missense or protein-truncating variants in CHD3, a gene in which de novo variants cause Snijders Blok-Campeau syndrome. Results Computational facial and Human Phenotype Ontologyâbased comparisons showed that the phenotype of probands with inherited CHD3 variants overlaps with the phenotype previously associated with de novo CHD3 variants, whereas heterozygote parents are mildly or not affected, suggesting variable expressivity. In addition, similarly reduced expression levels of CHD3 protein in cells of an affected proband and of healthy family members with a CHD3 protein-truncating variant suggested that compensation of expression from the wild-type allele is unlikely to be an underlying mechanism. Notably, most inherited CHD3 variants were maternally transmitted. Conclusion Our results point to a significant role of inherited variation in Snijders Blok-Campeau syndrome, a finding that is critical for correct variant interpretation and genetic counseling and warrants further investigation toward understanding the broader contributions of such variation to the landscape of human disease
Diagnostic accuracy of a three-gene Mycobacterium tuberculosis host response cartridge using fingerstick blood for childhood tuberculosis: a multicentre prospective study in low-income and middle-income countries
BACKGROUND: Childhood tuberculosis remains a major cause of morbidity and mortality in part due to missed diagnosis. Diagnostic methods with enhanced sensitivity using easy-to-obtain specimens are needed. We aimed to assess the diagnostic accuracy of the Cepheid Mycobacterium tuberculosis Host Response prototype cartridge (MTB-HR), a candidate test measuring a three-gene transcriptomic signature from fingerstick blood, in children with presumptive tuberculosis disease. METHODS: RaPaed-TB was a prospective diagnostic accuracy study conducted at four sites in African countries (Malawi, Mozambique, South Africa, and Tanzania) and one site in India. Children younger than 15 years with presumptive pulmonary or extrapulmonary tuberculosis were enrolled between Jan 21, 2019, and June 30, 2021. MTB-HR was performed at baseline and at 1 month in all children and was repeated at 3 months and 6 months in children on tuberculosis treatment. Accuracy was compared with tuberculosis status based on standardised microbiological, radiological, and clinical data. FINDINGS: 5313 potentially eligible children were screened, of whom 975 were eligible. 784 children had MTB-HR test results, of whom 639 had a diagnostic classification and were included in the analysis. MTB-HR differentiated children with culture-confirmed tuberculosis from those with unlikely tuberculosis with a sensitivity of 59·8% (95% CI 50·8â68·4). Using any microbiological confirmation (culture, Xpert MTB/RIF Ultra, or both), sensitivity was 41·6% (34·7â48·7), and using a composite clinical reference standard, sensitivity was 29·6% (25·4â34·2). Specificity for all three reference standards was 90·3% (95% CI 85·5â94·0). Performance was similar in different age groups and by malnutrition status. Among children living with HIV, accuracy against the strict reference standard tended to be lower (sensitivity 50·0%, 15·7â84·3) compared with those without HIV (61·0%, 51·6â69·9), although the difference did not reach statistical significance. Combining baseline MTB-HR result with one Ultra result identified 71·2% of children with microbiologically confirmed tuberculosis. INTERPRETATION: MTB-HR showed promising diagnostic accuracy for culture-confirmed tuberculosis in this large, geographically diverse, paediatric cohort and hard-to-diagnose subgroups. FUNDING: European and Developing Countries Clinical Trials Partnership, UK Medical Research Council, Swedish International Development Cooperation Agency, Bundesministerium fĂŒr Bildung und Forschung; German Center for Infection Research (DZIF)
Inherited variants in CHD3 show variable expressivity in Snijders Blok-Campeau syndrome
Purpose: Common diagnostic next-generation sequencing strategies are not optimized to identify inherited variants in genes associated with dominant neurodevelopmental disorders as causal when the transmitting parent is clinically unaffected, leaving a significant number of cases with neurodevelopmental disorders undiagnosed. Methods: We characterized 21 families with inherited heterozygous missense or protein-truncating variants in CHD3, a gene in which de novo variants cause Snijders Blok-Campeau syndrome. Results: Computational facial and Human Phenotype Ontologyâbased comparisons showed that the phenotype of probands with inherited CHD3 variants overlaps with the phenotype previously associated with de novo CHD3 variants, whereas heterozygote parents are mildly or not affected, suggesting variable expressivity. In addition, similarly reduced expression levels of CHD3 protein in cells of an affected proband and of healthy family members with a CHD3 protein-truncating variant suggested that compensation of expression from the wild-type allele is unlikely to be an underlying mechanism. Notably, most inherited CHD3 variants were maternally transmitted. Conclusion: Our results point to a significant role of inherited variation in Snijders Blok-Campeau syndrome, a finding that is critical for correct variant interpretation and genetic counseling and warrants further investigation toward understanding the broader contributions of such variation to the landscape of human disease
Clinical Presentation of a Complex Neurodevelopmental Disorder Caused by Mutations in ADNP
Background
In genome-wide screening studies for de novo mutations underlying autism and intellectual disability, mutations in the ADNP gene are consistently reported among the most frequent. ADNP mutations have been identified in children with autism spectrum disorder comorbid with intellectual disability, distinctive facial features, and deficits in multiple organ systems. However, a comprehensive clinical description of the Helsmoortel-Van der Aa syndrome is lacking.
Methods
We identified a worldwide cohort of 78 individuals with likely disruptive mutations in ADNP from January 2014 to October 2016 through systematic literature search, by contacting collaborators, and through direct interaction with parents. Clinicians filled in a structured questionnaire on genetic and clinical findings to enable correlations between genotype and phenotype. Clinical photographs and specialist reports were gathered. Parents were interviewed to complement the written questionnaires.
Results
We report on the detailed clinical characterization of a large cohort of individuals with an ADNP mutation and demonstrate a distinctive combination of clinical features, including mild to severe intellectual disability, autism, severe speech and motor delay, and common facial characteristics. Brain abnormalities, behavioral problems, sleep disturbance, epilepsy, hypotonia, visual problems, congenital heart defects, gastrointestinal problems, short stature, and hormonal deficiencies are common comorbidities. Strikingly, individuals with the recurrent p.Tyr719* mutation were more severely affected.
Conclusions
This overview defines the full clinical spectrum of individuals with ADNP mutations, a specific autism subtype. We show that individuals with mutations in ADNP have many overlapping clinical features that are distinctive from those of other autism and/or intellectual disability syndromes. In addition, our data show preliminary evidence of a correlation between genotype and phenotype.This work was supported by grants from the European Research Area Networks Network of European Funding for Neuroscience Research through the Research FoundationâFlanders and the Chief Scientist OfficeâMinistry of Health (to RFK, GV, IG). This research was supported, in part, by grants from the Simons Foundation Autism Research Initiative (Grant No. SFARI 303241 to EEE) and National Institutes of Health (Grant No. R01MH101221 to EEE). This work was also supported by the Italian Ministry of Health and â5 per milleâ funding (to CR). For many individuals, sequencing was provided by research initiatives like the Care4Rare Research Consortium in Canada or the Deciphering Developmental Disorders (DDD) study in the UK. The DDD Study presents independent research commissioned by the Health Innovation Challenge Fund (Grant No. HICF-1009â003), a parallel funding partnership between the Wellcome Trust and the Department of Health, and the Wellcome Trust Sanger Institute (Grant No. WT098051). The views expressed in this publication are those of the author(s) and not necessarily those of the Wellcome Trust or the Department of Health. The study has UK Research Ethics Committee approval (10/H0305/83, granted by the Cambridge South Research Ethics Committee, and GEN/284/12 granted by the Republic of Ireland Research Ethics Committee). The research team acknowledges the support of the National Institute for Health Research, through the Comprehensive Clinical Research Network
Loss-of-function mutations in UDP-Glucose 6-Dehydrogenase cause recessive developmental epileptic encephalopathy
Developmental epileptic encephalopathies are devastating disorders characterized by intractable epileptic seizures and developmental delay. Here, we report an allelic series of germline recessive mutations in UGDH in 36 cases from 25 families presenting with epileptic encephalopathy with developmental delay and hypotonia. UGDH encodes an oxidoreductase that converts UDP-glucose to UDP-glucuronic acid, a key component of specific proteoglycans and glycolipids. Consistent with being loss-of-function alleles, we show using patientsâ primary fibroblasts and biochemical assays, that these mutations either impair UGDH stability, oligomerization, or enzymatic activity. In vitro, patient-derived cerebral organoids are smaller with a reduced number of proliferating neuronal progenitors while mutant ugdh zebrafish do not phenocopy the human disease. Our study defines UGDH as a key player for the production of extracellular matrix components that are essential for human brain development. Based on the incidence of variants observed, UGDH mutations are likely to be a frequent cause of recessive epileptic encephalopathy
Swarm Learning for decentralized and confidential clinical machine learning
Fast and reliable detection of patients with severe and heterogeneous illnesses is a major goal of precision medicine. Patients with leukaemia can be identified using machine learning on the basis of their blood transcriptomes. However, there is an increasing divide between what is technically possible and what is allowed, because of privacy legislation. Here, to facilitate the integration of any medical data from any data owner worldwide without violating privacy laws, we introduce Swarm Learningâa decentralized machine-learning approach that unites edge computing, blockchain-based peer-to-peer networking and coordination while maintaining confidentiality without the need for a central coordinator, thereby going beyond federated learning. To illustrate the feasibility of using Swarm Learning to develop disease classifiers using distributed data, we chose four use cases of heterogeneous diseases (COVID-19, tuberculosis, leukaemia and lung pathologies). With more than 16,400 blood transcriptomes derived from 127 clinical studies with non-uniform distributions of cases and controls and substantial study biases, as well as more than 95,000 chest X-ray images, we show that Swarm Learning classifiers outperform those developed at individual sites. In addition, Swarm Learning completely fulfils local confidentiality regulations by design. We believe that this approach will notably accelerate the introduction of precision medicine
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