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A widely distributed metalloenzyme class enables gut microbial metabolism of host- and diet-derived catechols.
Catechol dehydroxylation is a central chemical transformation in the gut microbial metabolism of plant- and host-derived small molecules. However, the molecular basis for this transformation and its distribution among gut microorganisms are poorly understood. Here, we characterize a molybdenum-dependent enzyme from the human gut bacterium Eggerthella lenta that dehydroxylates catecholamine neurotransmitters. Our findings suggest that this activity enables E. lenta to use dopamine as an electron acceptor. We also identify candidate dehydroxylases that metabolize additional host- and plant-derived catechols. These dehydroxylases belong to a distinct group of largely uncharacterized molybdenum-dependent enzymes that likely mediate primary and secondary metabolism in multiple environments. Finally, we observe catechol dehydroxylation in the gut microbiotas of diverse mammals, confirming the presence of this chemistry in habitats beyond the human gut. These results suggest that the chemical strategies that mediate metabolism and interactions in the human gut are relevant to a broad range of species and habitats
Le Forum, Vol. 44 #1
https://digitalcommons.library.umaine.edu/francoamericain_forum/1103/thumbnail.jp
Le Forum, Vol. 45 #1 & #2
https://digitalcommons.library.umaine.edu/francoamericain_forum/1107/thumbnail.jp
Hematopoietic Cell Transplantation Cures Adenosine Deaminase 2 Deficiency : Report on 30 Patients
Correction; Early Access: ' DOI: 10.1007/s10875-022-01280-y Early Access: APR 2022Purpose Deficiency of adenosine deaminase 2 (DADA2) is an inherited inborn error of immunity, characterized by autoinflammation (recurrent fever), vasculopathy (livedo racemosa, polyarteritis nodosa, lacunar ischemic strokes, and intracranial hemorrhages), immunodeficiency, lymphoproliferation, immune cytopenias, and bone marrow failure (BMF). Tumor necrosis factor (TNF-alpha) blockade is the treatment of choice for the vasculopathy, but often fails to reverse refractory cytopenia. We aimed to study the outcome of hematopoietic cell transplantation (HCT) in patients with DADA2. Methods We conducted a retrospective study on the outcome of HCT in patients with DADA2. The primary outcome was overall survival (OS). Results Thirty DADA2 patients from 12 countries received a total of 38 HCTs. The indications for HCT were BMF, immune cytopenia, malignancy, or immunodeficiency. Median age at HCT was 9 years (range: 2-28 years). The conditioning regimens for the final transplants were myeloablative (n = 20), reduced intensity (n = 8), or non-myeloablative (n = 2). Donors were HLA-matched related (n = 4), HLA-matched unrelated (n = 16), HLA-haploidentical (n = 2), or HLA-mismatched unrelated (n = 8). After a median follow-up of 2 years (range: 0.5-16 years), 2-year OS was 97%, and 2-year GvHD-free relapse-free survival was 73%. The hematological and immunological phenotypes resolved, and there were no new vascular events. Plasma ADA2 enzyme activity normalized in 16/17 patients tested. Six patients required more than one HCT. Conclusion HCT was an effective treatment for DADA2, successfully reversing the refractory cytopenia, as well as the vasculopathy and immunodeficiency. Clinical Implications HCT is a definitive cure for DADA2 with > 95% survival.Peer reviewe
Integrated genomic characterization of oesophageal carcinoma
Oesophageal cancers are prominent worldwide; however, there are few targeted therapies and survival rates for these cancers remain dismal. Here we performed a comprehensive molecular analysis of 164 carcinomas of the oesophagus derived from Western and Eastern populations. Beyond known histopathological and epidemiologic distinctions, molecular features differentiated oesophageal squamous cell carcinomas from oesophageal adenocarcinomas. Oesophageal squamous cell carcinomas resembled squamous carcinomas of other organs more than they did oesophageal adenocarcinomas. Our analyses identified three molecular subclasses of oesophageal squamous cell carcinomas, but none showed evidence for an aetiological role of human papillomavirus. Squamous cell carcinomas showed frequent genomic amplifications of CCND1 and SOX2 and/or TP63, whereas ERBB2, VEGFA and GATA4 and GATA6 were more commonly amplified in adenocarcinomas. Oesophageal adenocarcinomas strongly resembled the chromosomally unstable variant of gastric adenocarcinoma, suggesting that these cancers could be considered a single disease entity. However, some molecular features, including DNA hypermethylation, occurred disproportionally in oesophageal adenocarcinomas. These data provide a framework to facilitate more rational categorization of these tumours and a foundation for new therapies
Correction to: Hematopoietic cell transplantation cures adenosine deaminase 2 deficiency: report on 30 patients
Correction to: Journal of Clinical Immunology (2021) 41:1633–164
Retrospective evaluation of whole exome and genome mutation calls in 746 cancer samples
Funder: NCI U24CA211006Abstract: The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) curated consensus somatic mutation calls using whole exome sequencing (WES) and whole genome sequencing (WGS), respectively. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, which aggregated whole genome sequencing data from 2,658 cancers across 38 tumour types, we compare WES and WGS side-by-side from 746 TCGA samples, finding that ~80% of mutations overlap in covered exonic regions. We estimate that low variant allele fraction (VAF < 15%) and clonal heterogeneity contribute up to 68% of private WGS mutations and 71% of private WES mutations. We observe that ~30% of private WGS mutations trace to mutations identified by a single variant caller in WES consensus efforts. WGS captures both ~50% more variation in exonic regions and un-observed mutations in loci with variable GC-content. Together, our analysis highlights technological divergences between two reproducible somatic variant detection efforts
A Low-Power Hybrid RO PUF With Improved Thermal Stability for Lightweight Applications
Ring oscillator (RO) based physical unclonable
function (PUF) is resilient against noise impacts, but its response
is susceptible to temperature variations. This paper presents
a low-power and small footprint hybrid RO PUF with a very
high temperature stability, which makes it an ideal candidate
for lightweight applications. The negative temperature coefficient
of the low-power subthreshold operation of current starved
inverters is exploited to mitigate the variations of differential
RO frequencies with temperature. The new architecture uses
conspicuously simplified circuitries to generate and compare
a large number of pairs of RO frequencies. The proposed 9-
stage hybrid RO PUF was fabricated using GF 65 nm CMOS
technology. The PUF occupies only 250 m2 of chip area and
consumes only 32.3 W per CRP at 1.2 V and 230 MHz. The
measured average and worst-case reliability of its responses
are 99.84% and 97.28%, respectively over a wide range of
temperature from 40 to 120 ◦C.MOE (Min. of Education, S’pore)Accepted versio
Fragment Couplings via CO<sub>2</sub> Extrusion–Recombination: Expansion of a Classic Bond-Forming Strategy via Metallaphotoredox
In this study we demonstrate that
molecular fragments, which can
be readily coupled via a simple, in situ ROCOR bond-forming
reaction, can subsequently undergo metal insertion–decarboxylation–recombination
to generate C<sub>sp<sup>2</sup></sub>–C<sub>sp<sup>3</sup></sub> bonds when subjected to metallaphotoredox catalysis.
In this embodiment the conversion of a wide variety of mixed anhydrides
(formed in situ from carboxylic acids and acyl chlorides) to fragment-coupled
ketones is accomplished in good to high yield. A three-step synthesis
of the medicinal agent edivoxetine is also described using this new
decarboxylation–recombination protocol
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