15 research outputs found
Aqueous alteration processes in Jezero crater, Mars—implications for organic geochemistry
The Perseverance rover landed in Jezero crater, Mars, in February 2021. We used the Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals (SHERLOC) instrument to perform deep-ultraviolet Raman and fluorescence spectroscopy of three rocks within the crater. We identify evidence for two distinct ancient aqueous environments at different times. Reactions with liquid water formed carbonates in an olivine-rich igneous rock. A sulfate-perchlorate mixture is present in the rocks, which probably formed by later modifications of the rocks by brine. Fluorescence signatures consistent with aromatic organic compounds occur throughout these rocks and are preserved in minerals related to both aqueous environments
A blood atlas of COVID-19 defines hallmarks of disease severity and specificity.
Treatment of severe COVID-19 is currently limited by clinical heterogeneity and incomplete description of specific immune biomarkers. We present here a comprehensive multi-omic blood atlas for patients with varying COVID-19 severity in an integrated comparison with influenza and sepsis patients versus healthy volunteers. We identify immune signatures and correlates of host response. Hallmarks of disease severity involved cells, their inflammatory mediators and networks, including progenitor cells and specific myeloid and lymphocyte subsets, features of the immune repertoire, acute phase response, metabolism, and coagulation. Persisting immune activation involving AP-1/p38MAPK was a specific feature of COVID-19. The plasma proteome enabled sub-phenotyping into patient clusters, predictive of severity and outcome. Systems-based integrative analyses including tensor and matrix decomposition of all modalities revealed feature groupings linked with severity and specificity compared to influenza and sepsis. Our approach and blood atlas will support future drug development, clinical trial design, and personalized medicine approaches for COVID-19
RET enhancer haplotype-dependent remodeling of the human fetal gut development program.
Hirschsprung disease (HSCR) is associated with deficiency of the receptor tyrosine kinase RET, resulting in loss of cells of the enteric nervous system (ENS) during fetal gut development. The major contribution to HSCR risk is from common sequence variants in RET enhancers with additional risk from rare coding variants in many genes. Here, we demonstrate that these RET enhancer variants specifically alter the human fetal gut development program through significant decreases in gene expression of RET, members of the RET-EDNRB gene regulatory network (GRN), other HSCR genes, with an altered transcriptome of 2,382 differentially expressed genes across diverse neuronal and mesenchymal functions. A parsimonious hypothesis for these results is that beyond RET's direct effect on its GRN, it also has a major role in enteric neural crest-derived cell (ENCDC) precursor proliferation, its deficiency reducing ENCDCs with relative expansion of non-ENCDC cells. Thus, genes reducing RET proliferative activity can potentially cause HSCR. One such class is the 23 RET-dependent transcription factors enriched in early gut development. We show that their knockdown in human neuroblastoma SK-N-SH cells reduces RET and/or EDNRB gene expression, expanding the RET-EDNRB GRN. The human embryos we studied had major remodeling of the gut transcriptome but were unlikely to have had HSCR: thus, genetic or epigenetic changes in addition to those in RET are required for aganglionosis
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De Novo Mutation in an Enhancer of EBF3 in simplex autism
AbstractPrevious research in autism and other neurodevelopmental disorders (NDDs) has indicated an important contribution of de novo protein-coding variants within specific genes. The role of de novo noncoding variation has been observable as a general increase in genetic burden but has yet to be resolved to individual functional elements. In this study, we assessed whole-genome sequencing data in 2,671 families with autism, with a specific focus on de novo variation in enhancers with previously characterized in vivo activity. We identified three independent de novo mutations limited to individuals with autism in the enhancer hs737. These mutations result in similar phenotypic characteristics, affect enhancer activity in vitro, and preferentially occur in AAT motifs in the enhancer with predicted disruptions of transcription factor binding. We also find that hs737 is enriched for copy number variation in individuals with NDDs, is dosage sensitive in the human population, is brain-specific, and targets the NDD gene EBF3 that is genome-wide significant for protein coding de novo variants, demonstrating the importance of understanding all forms of variation in the genome.One Sentence SummaryWhole-genome sequencing in thousands of families reveals variants relevant to simplex autism in a brain enhancer of the well-established neurodevelopmental disorder gene EBF3
Clinical outcomes and bacterial characteristics of carbapenem-resistant Klebsiella pneumoniae complex among patients from different global regions (CRACKLE-2): a prospective, multicentre, cohort study
Q1Q1Background Carbapenem-resistant Klebsiella pneumoniae (CRKP) is a global threat. We therefore analysed the bacterial
characteristics of CRKP infections and the clinical outcomes of patients with CRKP infections across different
countries.
Methods In this prospective, multicentre, cohort study (CRACKLE-2), hospitalised patients with cultures positive for
CRKP were recruited from 71 hospitals in Argentina, Australia, Chile, China, Colombia, Lebanon, Singapore, and the
USA. The first culture positive for CRKP was included for each unique patient. Clinical data on post-hospitalisation
death and readmission were collected from health records, and whole genome sequencing was done on all isolates.
The primary outcome was a desirability of outcome ranking at 30 days after the index culture, and, along with bacterial
characteristics and 30-day all-cause mortality (a key secondary outcome), was compared between patients from China,
South America, and the USA. The desirability of outcome ranking was adjusted for location before admission,
Charlson comorbidity index, age at culture, Pitt bacteremia score, and anatomical culture source through inverse
probability weighting; mortality was adjusted for the same confounders, plus region where relevant, through
multivariable logistic regression. This study is registered at ClinicalTrials.gov, NCT03646227, and is complete.
Findings Between June 13, 2017, and Nov 30, 2018, 991 patients were enrolled, of whom 502 (51%) met the criteria for
CRKP infection and 489 (49%) had positive cultures that were considered colonisation. We observed little intracountry genetic variation in CRKP. Infected patients from the USA were more acutely ill than were patients from
China or South America (median Pitt bacteremia score 3 [IQR 2–6] vs 2 [0–4] vs 2 [0–4]) and had more comorbidities
(median Charlson comorbidity index 3 [IQR 2–5] vs 1 [0–3] vs 1 [0–2]). Adjusted desirability of outcome ranking
outcomes were similar in infected patients from China (n=246), South America (n=109), and the USA (n=130); the
estimates were 53% (95% CI 42–65) for China versus South America, 50% (41–61) for the USA versus China, and
53% (41–66) for the USA versus South America. In patients with CRKP infections, unadjusted 30-day mortality was
lower in China (12%, 95% CI 8–16; 29 of 246) than in the USA (23%, 16–30; 30 of 130) and South America (28%, 20–37;
31 of 109). Adjusted 30-day all-cause mortality was higher in South America than in China (adjusted odds ratio
[aOR] 4·82, 95% CI 2·22–10·50) and the USA (aOR 3·34, 1·50–7·47), with the mortality difference between the USA
and China no longer being significant (aOR 1·44, 0·70–2·96).
Interpretation Global CRKP epidemics have important regional differences in patients’ baseline characteristics and
clinical outcomes, and in bacterial characteristics. Research findings from one region might not be generalisable to
other regions.Revista Internacional - IndexadaN
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Clinical outcomes and bacterial characteristics of carbapenem-resistant Klebsiella pneumoniae complex among patients from different global regions (CRACKLE-2): a prospective, multicentre, cohort study
BackgroundCarbapenem-resistant Klebsiella pneumoniae (CRKP) is a global threat. We therefore analysed the bacterial characteristics of CRKP infections and the clinical outcomes of patients with CRKP infections across different countries.MethodsIn this prospective, multicentre, cohort study (CRACKLE-2), hospitalised patients with cultures positive for CRKP were recruited from 71 hospitals in Argentina, Australia, Chile, China, Colombia, Lebanon, Singapore, and the USA. The first culture positive for CRKP was included for each unique patient. Clinical data on post-hospitalisation death and readmission were collected from health records, and whole genome sequencing was done on all isolates. The primary outcome was a desirability of outcome ranking at 30 days after the index culture, and, along with bacterial characteristics and 30-day all-cause mortality (a key secondary outcome), was compared between patients from China, South America, and the USA. The desirability of outcome ranking was adjusted for location before admission, Charlson comorbidity index, age at culture, Pitt bacteremia score, and anatomical culture source through inverse probability weighting; mortality was adjusted for the same confounders, plus region where relevant, through multivariable logistic regression. This study is registered at ClinicalTrials.gov, NCT03646227, and is complete.FindingsBetween June 13, 2017, and Nov 30, 2018, 991 patients were enrolled, of whom 502 (51%) met the criteria for CRKP infection and 489 (49%) had positive cultures that were considered colonisation. We observed little intra-country genetic variation in CRKP. Infected patients from the USA were more acutely ill than were patients from China or South America (median Pitt bacteremia score 3 [IQR 2-6] vs 2 [0-4] vs 2 [0-4]) and had more comorbidities (median Charlson comorbidity index 3 [IQR 2-5] vs 1 [0-3] vs 1 [0-2]). Adjusted desirability of outcome ranking outcomes were similar in infected patients from China (n=246), South America (n=109), and the USA (n=130); the estimates were 53% (95% CI 42-65) for China versus South America, 50% (41-61) for the USA versus China, and 53% (41-66) for the USA versus South America. In patients with CRKP infections, unadjusted 30-day mortality was lower in China (12%, 95% CI 8-16; 29 of 246) than in the USA (23%, 16-30; 30 of 130) and South America (28%, 20-37; 31 of 109). Adjusted 30-day all-cause mortality was higher in South America than in China (adjusted odds ratio [aOR] 4·82, 95% CI 2·22-10·50) and the USA (aOR 3·34, 1·50-7·47), with the mortality difference between the USA and China no longer being significant (aOR 1·44, 0·70-2·96).InterpretationGlobal CRKP epidemics have important regional differences in patients' baseline characteristics and clinical outcomes, and in bacterial characteristics. Research findings from one region might not be generalisable to other regions.FundingThe National Institutes of Health
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Increased mortality in hospital- compared to community-onset carbapenem-resistant enterobacterales infections
Abstract Background The CDC reported a 35% increase in hospital-onset (HO) carbapenem-resistant Enterobacterales (CRE) infections during the COVID-19 pandemic. We evaluated patient outcomes following HO and community-onset (CO) CRE bloodstream infections (BSI). Methods Patients prospectively enrolled in CRACKLE-2 from 56 hospitals in 10 countries between 30 April 2016 and 30 November 2019 with a CRE BSI were eligible. Infections were defined as CO or HO by CDC guidelines, and clinical characteristics and outcomes were compared. The primary outcome was desirability of outcome ranking (DOOR) 30 days after index culture. Difference in 30-day mortality was calculated with 95% CI. Results Among 891 patients with CRE BSI, 65% were HO (582/891). Compared to those with CO CRE, patients with HO CRE were younger [median 60 (Q1 42, Q3 70) years versus 65 (52, 74); P < 0.001], had fewer comorbidities [median Charlson comorbidity index 2 (1, 4) versus 3 (1, 5); P = 0.002] and were more acutely ill (Pitt bacteraemia score ≥4: 47% versus 32%; P < 0.001). The probability of a better DOOR outcome in a randomly selected patient with CO BSI compared to a patient with HO BSI was 60.6% (95% CI: 56.8%–64.3%). Mortality at 30-days was 12% higher in HO BSI (192/582; 33%) than CO BSI [66/309 (21%); P < 0.001]. Conclusion We found a disproportionately greater impact on patient outcomes with HO compared to CO CRE BSIs; thus, the recently reported increases in HO CRE infections by CDC requires rigorous surveillance and infection prevention methods to prevent added mortality
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Clinical Outcomes and Bacterial Characteristics of Carbapenem-Resistant Acinetobacter baumannii Among Patients from Different Global Regions
Abstract Background Carbapenem-resistant Acinetobacter baumannii (CRAb) is one of the most problematic antimicrobial-resistant bacteria. We sought to elucidate the international epidemiology and clinical impact of CRAb. Methods In a prospective observational cohort study, 842 hospitalized patients with a clinical CRAb culture were enrolled at 46 hospitals in five global regions between 2017 and 2019. The primary outcome was all-cause mortality at 30 days from the index culture. The strains underwent whole-genome analysis. Results Of 842 cases, 536 (64%) represented infection. By 30 days, 128 (24%) of the infected patients died, ranging from 1 (6%) of 18 in Australia-Singapore to 54 (25%) of 216 in the United States and 24 (49%) of 49 in South-Central America, whereas 42 (14%) of non-infected patients died. Bacteremia was associated with a higher risk of death compared with other types of infection (40 [42%] of 96 vs. 88 [20%] of 440). In a multivariable logistic regression analysis, bloodstream infection and higher age-adjusted Charlson comorbidity index were independently associated with 30-day mortality. Clonal group 2 (CG2) strains predominated except in South-Central America, ranging from 216 (59%) of 369 in the United States to 282 (97%) of 291 in China. Acquired carbapenemase genes were carried by 769 (91%) of the 842 isolates. CG2 strains were significantly associated with higher levels of meropenem resistance, yet non-CG2 cases were over-represented among the deaths compared with CG2 cases. Conclusions CRAb infection types and clinical outcomes differed significantly across regions. While CG2 strains remained predominant, non-CG2 strains were associated with higher mortality. ClinicalTrials.gov #NCT0364622