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Frederick Epstein opublikował 1 rok, 3 miesiące temu
Each 20% lower clearance of isovalerylglycine and xanthosine were associated with a 16 mL/min lower (95% CI, 5-26 mL/min lower) and 19 mL/min lower (95% CI, 7-31 mL/min lower) insulin clearance, respectively. Neither estimated GFR nor secretory solute clearances were associated with insulin sensitivity after adjustment.
These results highlight the importance of tubular secretory pathways to insulin elimination but suggest that kidney functions in aggregate contribute only modestly to systemic insulin clearance.
These results highlight the importance of tubular secretory pathways to insulin elimination but suggest that kidney functions in aggregate contribute only modestly to systemic insulin clearance.
Testosterone treatment of hypogonadal men improves their hemoglobin, but the mechanism is not understood.
To investigate possible mechanisms by which testosterone stimulates erythropoiesis in hypogonadal older men with unexplained or iron-deficiency anemia.
The Anemia Trial of The Testosterone Trials, a placebo-controlled study in older, hypogonadal men.
Twelve academic medical centers.
A total of 95 hypogonadal men (testosterone < 275 ng/mL) ≥65 years with anemia (hemoglobin < 12.7 g/dL). They were classified as having unexplained (n = 58) or iron deficiency anemia (n = 37).
Testosterone or placebo gel for 1 year.
Markers of iron metabolism during the first 3 months of treatment.
Testosterone replacement significantly (P < 0.001) increased hemoglobin in the 58 men who had unexplained anemia (adjusted mean difference 0.58 g/dL; 95% confidence interval, 0.31-0.85). Testosterone replacement tended to increase hemoglobin in the 37 men who had iron deficiency (0.38 g/dL; -0.19, 0.95), but the response was more variable and not statistically significant (P = 0.19). In men with unexplained anemia, testosterone replacement suppressed hepcidin (-8.2 ng/mL; -13.7, -2.7; P = 0.004) and ferritin (-19.6 µg/L; -32.8, -6.3; P = 0.004), but in men with iron deficiency, testosterone replacement did not. The decrease in hepcidin was moderately correlated with the increase in hemoglobin in the men with unexplained anemia (correlation coefficient -0.35, P = 0.01) but not in those with iron deficiency anemia (correlation coefficient -0.07, P = 0.73).
Testosterone replacement of older hypogonadal men with unexplained anemia stimulates erythropoiesis associated with increased iron mobilization. This effect appears to be attenuated by iron deficiency.
Testosterone replacement of older hypogonadal men with unexplained anemia stimulates erythropoiesis associated with increased iron mobilization. This effect appears to be attenuated by iron deficiency.Divergence of gene function and expression during development can give rise to phenotypic differences at the level of cells, tissues, organs, and ultimately whole organisms. To gain insights into the evolution of gene expression and novel genes at spatial resolution, we compared the spatially resolved transcriptomes of two distantly related nematodes, Caenorhabditis elegans and Pristionchus pacificus, that diverged 60-90 Ma. The spatial transcriptomes of adult worms show little evidence for strong conservation at the level of single genes. Instead, regional expression is largely driven by recent duplication and emergence of novel genes. Estimation of gene ages across anatomical structures revealed an enrichment of novel genes in sperm-related regions. This provides first evidence in nematodes for the „out of testis” hypothesis that has been previously postulated based on studies in Drosophila and mammals. „Out of testis” genes represent a mix of products of pervasive transcription as well as fast evolving members of ancient gene families. Strikingly, numerous novel genes have known functions during meiosis in Caenorhabditis elegans indicating that even universal processes such as meiosis may be targets of rapid evolution. Our study highlights the importance of novel genes in generating phenotypic diversity and explicitly characterizes gene origination in sperm-related regions. Furthermore, it proposes new functions for previously uncharacterized genes and establishes the spatial transcriptome of Pristionchus pacificus as a catalog for future studies on the evolution of gene expression and function.With the rapid global spread of SARS-CoV-2, we have become acutely aware of the inadequacies of our ability to respond to viral epidemics. Although disrupting the viral life cycle is critical for limiting viral spread and disease, it has proven challenging to develop targeted and selective therapeutics. Synthetic lethality offers a promising but largely unexploited strategy against infectious viral disease; as viruses infect cells, they abnormally alter the cell state, unwittingly exposing new vulnerabilities in the infected cell. Therefore, we propose that effective therapies can be developed to selectively target the virally reconfigured host cell networks that accompany altered cellular states to cripple the host cell that has been converted into a virus factory, thus disrupting the viral life cycle.Gene tree discordance in large genomic data sets can be caused by evolutionary processes such as incomplete lineage sorting and hybridization, as well as model violation, and errors in data processing, orthology inference, and gene tree estimation. Species tree methods that identify and accommodate all sources of conflict are not available, but a combination of multiple approaches can help tease apart alternative sources of conflict. Here, using a phylotranscriptomic analysis in combination with reference genomes, we test a hypothesis of ancient hybridization events within the plant family Amaranthaceae s.l. that was previously supported by morphological, ecological, and Sanger-based molecular data. The data set included seven genomes and 88 transcriptomes, 17 generated for this study. We examined gene-tree discordance using coalescent-based species trees and network inference, gene tree discordance analyses, site pattern tests of introgression, topology tests, synteny analyses, and simulations. We found that a combination of processes might have generated the high levels of gene tree discordance in the backbone of Amaranthaceae s.l. Furthermore, we found evidence that three consecutive short internal branches produce anomalous trees contributing to the discordance. Overall, our results suggest that Amaranthaceae s.l. might be a product of an ancient and rapid lineage diversification, and remains, and probably will remain, unresolved. This work highlights the potential problems of identifiability associated with the sources of gene tree discordance including, in particular, phylogenetic network methods. Our results also demonstrate the importance of thoroughly testing for multiple sources of conflict in phylogenomic analyses, especially in the context of ancient, rapid radiations. We provide several recommendations for exploring conflicting signals in such situations. [Amaranthaceae; gene tree discordance; hybridization; incomplete lineage sorting; phylogenomics; species network; species tree; transcriptomics.].
In the wake of the US opioid epidemic, there have been efforts to curb opioid prescribing. However, it is unknown whether these efforts have affected prescribing among oncologists, whose patients often require opioids for symptom management. We investigated temporal patterns in opioid prescribing for Medicare beneficiaries among oncologists and nononcologists.
We queried the Centers for Medicare and Medicaid Services Part D prescriber dataset for all physicians between January 1, 2013, and December 31, 2017. We used population-averaged multivariable negative binomial regression to estimate the association between time and per-provider opioid and gabapentinoid prescribing rate, defined as the annual number of drug claims (original prescriptions and refills) per beneficiary, among oncologists and nononcologists on a national and state level.
From 2013 to 2017, the national opioid-prescribing rate declined by 20.7% (P < .001) among oncologists and 22.8% (P < .001) among non oncologists. During this tes in opioid prescribing among oncologists and nononcologists, there is concern that opioid-prescribing guidelines intended for the noncancer population are being applied inappropriately to patients with cancer and cancer survivors.Sickle cell disease (SCD) is the most common inherited blood disorder in the United States. It is a medically and socially complex, multisystem illness that affects individuals throughout the lifespan. Given improvements in care, most children with SCD survive into adulthood. However, access to adult sickle cell care is poor in many parts of the United States, resulting in increased acute care utilization, disjointed care delivery, and early mortality for patients. A dearth of nonmalignant hematology providers, the lack of a national SCD registry, and the absence of a centralized infrastructure to facilitate comparative quality assessment compounds these issues. As part of a workshop designed to train health care professionals in the skills necessary to establish clinical centers focused on the management of adults living with SCD, we defined an SCD center, elucidated required elements of a comprehensive adult SCD center, and discussed different models of care. There are also important economic impacts of these centers at an institutional and health system level. As more clinicians are trained in providing adult-focused SCD care, center designation will enhance the ability to undertake quality improvement and compare outcomes between SCD centers. Activities will include an assessment of the clinical effectiveness of expanded access to care, the implementation of SCD guidelines, and the efficacy of newly approved targeted medications. Details of this effort are provided.
The Diamond Princess cruise ship was the site of a large outbreak of coronavirus disease 2019 (COVID-19). Of 437 Americans and their travel companions on the ship, 114 (26%) tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).
We interviewed 229 American passengers and crew after disembarkation following a ship-based quarantine to identify risk factors for infection and characterize transmission onboard the ship.
The attack rate for passengers in single-person cabins or without infected cabinmates was 18% (58/329), compared with 63% (27/43) for those sharing a cabin with an asymptomatic infected cabinmate, and 81% (25/31) for those with a symptomatic infected cabinmate. Whole genome sequences from specimens from passengers who shared cabins clustered together. Of 66 SARS-CoV-2-positive American travelers with complete symptom information, 14 (21%) were asymptomatic while on the ship. Among SARS-CoV-2-positive Americans, 10 (9%) required intensive care, of whom 7 were ≥70 yea of future cruise travel during the pandemic, given typical cruise passenger demographics. The magnitude and severe outcomes of this outbreak were major factors contributing to the Centers for Disease Control and Prevention’s decision to halt cruise ship travel in U.S. waters in March 2020.The ribosome’s common core, comprised of ribosomal RNA (rRNA) and universal ribosomal proteins, connects all life back to a common ancestor and serves as a window to relationships among organisms. The rRNA of the common core is similar to rRNA of extant bacteria. In eukaryotes, the rRNA of the common core is decorated by expansion segments (ESs) that vastly increase its size. Supersized ESs have not been observed previously in Archaea, and the origin of eukaryotic ESs remains enigmatic. We discovered that the large ribosomal subunit (LSU) rRNA of two Asgard phyla, Lokiarchaeota and Heimdallarchaeota, considered to be the closest modern archaeal cell lineages to Eukarya, bridge the gap in size between prokaryotic and eukaryotic LSU rRNAs. The elongated LSU rRNAs in Lokiarchaeota and Heimdallarchaeota stem from two supersized ESs, called ES9 and ES39. We applied chemical footprinting experiments to study the structure of Lokiarchaeota ES39. Furthermore, we used covariation and sequence analysis to study the evolution of Asgard ES39s and ES9s.


