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"Ward, Patrick"
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A & R pioneers : architects of American roots music on record
\"A&R Pioneers offers the first comprehensive account of the diverse group of men and women who pioneered artists-and-repertoire (A&R) work in the early US recording industry. In the process, they helped create much of what we now think of as American roots music. Resourceful, innovative, and, at times, shockingly unscrupulous, they scouted and signed many of the singers and musicians who came to define American roots music between the two world wars. They also shaped the repertoires and musical styles of their discoveries, supervised recording sessions, and then devised marketing campaigns to sell the resulting records. By World War II, they had helped redefine the canons of American popular music and established the basic structure and practices of the modern recording industry. Moreover, though their musical interests, talents, and sensibilities varied enormously, these A&R pioneers created the template for the job that would subsequently become known as \"record producer.\" Without Ralph Peer, Art Satherley, Frank Walker, Polk C. Brockman, Eli Oberstein, Don Law, Lester Melrose, J. Mayo Williams, John Hammond, Helen Oakley Dance, and a whole army of lesser known but often hugely influential A&R representatives, the music of Bessie Smith and Bob Wills, of the Carter Family and Count Basie, of Robert Johnson and Jimmie Rodgers may never have found its way onto commercial records and into the heart of America's musical heritage. This is their story\" -- Book jacket.
Experimental evidence on cooperation and coordination in forest and endangered species conservation in China
2022
The growing prevalence of livestock as an alternative or complementary livelihood strategy has become a growing threat to wildlife and forest ecosystems in China. To achieve the dual objectives of biodiversity conservation and rural development requires cooperation and coordination from local communities. However, relatively little is known about the prevalence of these social attitudes in rural China, nor the extent to which cooperation and coordination could be leveraged for the enhanced natural resource management. In this study, we used a series of experimental games to study the propensity for cooperation in the management of common property resources among rural communities in national panda nature reserves in Gansu and Sichuan provinces. We also explored how variations in socioeconomic factors may explain differences in participants' voluntary contribution patterns. Our results show that expected cooperation among peers was a major determinant of voluntary cooperation under the provision point mechanism but not the voluntary contribution mechanism. The risk in the collective returns reduced the chance for voluntary cooperation while the private risk did not show a significant effect. Other socioeconomic factors contributed little to the voluntary cooperation behaviors. Our study suggests that alleviating uncertainty of rural resident's income could enhance collective action in endangered species conservation. A cooperative with support from the government to lower the potential risk in returns could be effective in managing the livestock number and promote sustainable livelihoods around protected areas.
Journal Article
Disparities in Opioid Overdose Death Trends by Race/Ethnicity, 2018–2019, From the HEALing Communities Study
2021
Objectives. To examine trends in opioid overdose deaths by race/ethnicity from 2018 to 2019 across 67 HEALing Communities Study (HCS) communities in Kentucky, New York, Massachusetts, and Ohio.
Methods. We used state death certificate records to calculate opioid overdose death rates per 100 000 adult residents of the 67 HCS communities for 2018 and 2019. We used Poisson regression to calculate the ratio of 2019 to 2018 rates. We compared changes by race/ethnicity by calculating a ratio of rate ratios (RRR) for each racial/ethnic group compared with non-Hispanic White individuals.
Results. Opioid overdose death rates were 38.3 and 39.5 per 100 000 for 2018 and 2019, respectively, without a significant change from 2018 to 2019 (rate ratio = 1.03; 95% confidence interval [CI] = 0.98, 1.08). We estimated a 40% increase in opioid overdose death rate for non-Hispanic Black individuals (RRR = 1.40; 95% CI = 1.22, 1.62) relative to non-Hispanic White individuals but no change among other race/ethnicities.
Conclusions. Overall opioid overdose death rates have leveled off but have increased among non-Hispanic Black individuals.
Public Health Implications. An antiracist public health approach is needed to address the crisis of opioid-related harms. (Am J Public Health. 2021;111(10):1851–1854. https://doi.org/10.2105/AJPH.2021.306431 )
Journal Article
Pyruvate kinase M2 promotes de novo serine synthesis to sustain mTORC1 activity and cell proliferation
by
Tong, Xuemei
,
Ye, Jiangbin
,
Thompson, Craig B
in
Activating Transcription Factor 4
,
Activating Transcription Factor 4 - metabolism
,
Amino acids
2012
Despite the fact that most cancer cells display high glycolytic activity, cancer cells selectively express the less active M2 isoform of pyruvate kinase (PKM2). Here we demonstrate that PKM2 expression makes a critical regulatory contribution to the serine synthetic pathway. In the absence of serine, an allosteric activator of PKM2, glycolytic efflux to lactate is significantly reduced in PKM2-expressing cells. This inhibition of PKM2 results in the accumulation of glycolytic intermediates that feed into serine synthesis. As a consequence, PKM2-expressing cells can maintain mammalian target of rapamycin complex 1 activity and proliferate in serine-depleted medium, but PKM1-expressing cells cannot. Cellular detection of serine depletion depends on general control nonderepressible 2 kinase-activating transcription factor 4 (GCN2-ATF4) pathway activation and results in increased expression of enzymes required for serine synthesis from the accumulating glycolytic precursors. These findings suggest that tumor cells use serine-dependent regulation of PKM2 and GCN2 to modulate the flux of glycolytic intermediates in support of cell proliferation.
Journal Article
IDH mutation impairs histone demethylation and results in a block to cell differentiation
by
Kapoor, Gurpreet S.
,
Chan, Timothy A.
,
Abdel-Wahab, Omar
in
3T3-L1 Cells
,
631/208/737
,
631/337/100/2285
2012
Cancer-associated IDH mutants that produce 2-hydroxyglutarate are shown to prevent the histone demethylation that is required for lineage-specific progenitor cells to differentiate into terminally differentiated cells.
Cancer induction by isocitrate dehydrogenase mutation
Mutations in the isocitrate dehydrogenase genes
IDH1
and
IDH2
have been identified in gliomas, the most common form of brain tumour, and in other cancers including leukaemias. The mutated enzymes produce 2-hydroxyglutarate (2HG), which is a potential oncometabolite. Three papers in this issue of
Nature
examine the mechanisms through which IDH mutations promote cancers. Lu
et al
. show that 2HG-producing IDH mutants can prevent the histone demethylation that is required for progenitor cells to differentiate, potentially contributing to tumour-cell accumulation. Turcan
et al
. show that
IDH1
mutation in primary human astrocytes induces DNA hypermethylation and reshapes the methylome to resemble that of the CIMP phenotype, a common feature of gliomas and other solid tumours. Koivunen
et al
. show that the (
R
)-enantiomer of 2HG (but not the (
S
)-enantiomer) can stimulate the activity of the EGLN prolyl 4-hydroxylases, leading to diminished levels of hypoxia-inducible factor (HIF), which in turn can enhance cell proliferation. These papers establish a framework for understanding gliomagenesis and highlight the interplay between genomic and epigenomic changes in human cancers.
Recurrent mutations in isocitrate dehydrogenase 1 (IDH1) and IDH2 have been identified in gliomas, acute myeloid leukaemias (AML) and chondrosarcomas, and share a novel enzymatic property of producing 2-hydroxyglutarate (2HG) from α-ketoglutarate
1
,
2
,
3
,
4
,
5
,
6
. Here we report that 2HG-producing IDH mutants can prevent the histone demethylation that is required for lineage-specific progenitor cells to differentiate into terminally differentiated cells. In tumour samples from glioma patients, IDH mutations were associated with a distinct gene expression profile enriched for genes expressed in neural progenitor cells, and this was associated with increased histone methylation. To test whether the ability of IDH mutants to promote histone methylation contributes to a block in cell differentiation in non-transformed cells, we tested the effect of neomorphic IDH mutants on adipocyte differentiation
in vitro
. Introduction of either mutant IDH or cell-permeable 2HG was associated with repression of the inducible expression of lineage-specific differentiation genes and a block to differentiation. This correlated with a significant increase in repressive histone methylation marks without observable changes in promoter DNA methylation. Gliomas were found to have elevated levels of similar histone repressive marks. Stable transfection of a 2HG-producing mutant IDH into immortalized astrocytes resulted in progressive accumulation of histone methylation. Of the marks examined, increased H3K9 methylation reproducibly preceded a rise in DNA methylation as cells were passaged in culture. Furthermore, we found that the 2HG-inhibitable H3K9 demethylase KDM4C was induced during adipocyte differentiation, and that RNA-interference suppression of KDM4C was sufficient to block differentiation. Together these data demonstrate that 2HG can inhibit histone demethylation and that inhibition of histone demethylation can be sufficient to block the differentiation of non-transformed cells.
Journal Article
Hypoxia promotes isocitrate dehydrogenase-dependent carboxylation of α-ketoglutarate to citrate to support cell growth and viability
by
Shay, Jessica E. S
,
Platt, Jesse M
,
Thompson, Craig B
in
acetyl coenzyme A
,
Anaerobic conditions
,
Biological Sciences
2011
Citrate is a critical metabolite required to support both mitochondrial bioenergetics and cytosolic macromolecular synthesis. When cells proliferate under normoxic conditions, glucose provides the acetyl-CoA that condenses with oxaloacetate to support citrate production. Tricarboxylic acid (TCA) cycle anaplerosis is maintained primarily by glutamine. Here we report that some hypoxic cells are able to maintain cell proliferation despite a profound reduction in glucose-dependent citrate production. In these hypoxic cells, glutamine becomes a major source of citrate. Glutamine-derived α-ketoglutarate is reductively carboxylated by the NADPH-linked mitochondrial isocitrate dehydrogenase (IDH2) to form isocitrate, which can then be isomerized to citrate. The increased IDH2-dependent carboxylation of glutamine-derived α-ketoglutarate in hypoxia is associated with a concomitant increased synthesis of 2-hydroxyglutarate (2HG) in cells with wild-type IDH1 and IDH2. When either starved of glutamine or rendered IDH2-deficient by RNAi, hypoxic cells are unable to proliferate. The reductive carboxylation of glutamine is part of the metabolic reprogramming associated with hypoxia-inducible factor 1 (HIF1), as constitutive activation of HIF1 recapitulates the preferential reductive metabolism of glutamine-derived α-ketoglutarate even in normoxic conditions. These data support a role for glutamine carboxylation in maintaining citrate synthesis and cell growth under hypoxic conditions.
Journal Article
IDH1 mutation is sufficient to establish the glioma hypermethylator phenotype
2012
Mutation of isocitrate dehydrogenase 1 (IDH1) is shown to induce DNA hypermethylation and to remodel the epigenome to resemble that of gliomas with the CpG island methylator phenotype.
Cancer induction by isocitrate dehydrogenase mutation
Mutations in the isocitrate dehydrogenase genes
IDH1
and
IDH2
have been identified in gliomas, the most common form of brain tumour, and in other cancers including leukaemias. The mutated enzymes produce 2-hydroxyglutarate (2HG), which is a potential oncometabolite. Three papers in this issue of
Nature
examine the mechanisms through which IDH mutations promote cancers. Lu
et al
. show that 2HG-producing IDH mutants can prevent the histone demethylation that is required for progenitor cells to differentiate, potentially contributing to tumour-cell accumulation. Turcan
et al
. show that
IDH1
mutation in primary human astrocytes induces DNA hypermethylation and reshapes the methylome to resemble that of the CIMP phenotype, a common feature of gliomas and other solid tumours. Koivunen
et al
. show that the (
R
)-enantiomer of 2HG (but not the (
S
)-enantiomer) can stimulate the activity of the EGLN prolyl 4-hydroxylases, leading to diminished levels of hypoxia-inducible factor (HIF), which in turn can enhance cell proliferation. These papers establish a framework for understanding gliomagenesis and highlight the interplay between genomic and epigenomic changes in human cancers.
Both genome-wide genetic and epigenetic alterations are fundamentally important for the development of cancers, but the interdependence of these aberrations is poorly understood. Glioblastomas and other cancers with the CpG island methylator phenotype (CIMP) constitute a subset of tumours with extensive epigenomic aberrations and a distinct biology
1
,
2
,
3
. Glioma CIMP (G-CIMP) is a powerful determinant of tumour pathogenicity, but the molecular basis of G-CIMP remains unresolved. Here we show that mutation of a single gene, isocitrate dehydrogenase 1 (
IDH1
), establishes G-CIMP by remodelling the methylome. This remodelling results in reorganization of the methylome and transcriptome. Examination of the epigenome of a large set of intermediate-grade gliomas demonstrates a distinct G-CIMP phenotype that is highly dependent on the presence of
IDH
mutation. Introduction of mutant IDH1 into primary human astrocytes alters specific histone marks, induces extensive DNA hypermethylation, and reshapes the methylome in a fashion that mirrors the changes observed in G-CIMP-positive lower-grade gliomas. Furthermore, the epigenomic alterations resulting from mutant IDH1 activate key gene expression programs, characterize G-CIMP-positive proneural glioblastomas but not other glioblastomas, and are predictive of improved survival. Our findings demonstrate that IDH mutation is the molecular basis of CIMP in gliomas, provide a framework for understanding oncogenesis in these gliomas, and highlight the interplay between genomic and epigenomic changes in human cancers.
Journal Article
Enhancing timeliness of drug overdose mortality surveillance: A machine learning approach
by
Rock, Peter J.
,
Bunn, Terry L.
,
Kavuluru, Ramakanth
in
Artificial intelligence
,
Cause of Death
,
Certificates
2019
Timely data is key to effective public health responses to epidemics. Drug overdose deaths are identified in surveillance systems through ICD-10 codes present on death certificates. ICD-10 coding takes time, but free-text information is available on death certificates prior to ICD-10 coding. The objective of this study was to develop a machine learning method to classify free-text death certificates as drug overdoses to provide faster drug overdose mortality surveillance.
Using 2017-2018 Kentucky death certificate data, free-text fields were tokenized and features were created from these tokens using natural language processing (NLP). Word, bigram, and trigram features were created as well as features indicating the part-of-speech of each word. These features were then used to train machine learning classifiers on 2017 data. The resulting models were tested on 2018 Kentucky data and compared to a simple rule-based classification approach. Documented code for this method is available for reuse and extensions: https://github.com/pjward5656/dcnlp.
The top scoring machine learning model achieved 0.96 positive predictive value (PPV) and 0.98 sensitivity for an F-score of 0.97 in identification of fatal drug overdoses on test data. This machine learning model achieved significantly higher performance for sensitivity (p<0.001) than the rule-based approach. Additional feature engineering may improve the model's prediction. This model can be deployed on death certificates as soon as the free-text is available, eliminating the time needed to code the death certificates.
Machine learning using natural language processing is a relatively new approach in the context of surveillance of health conditions. This method presents an accessible application of machine learning that improves the timeliness of drug overdose mortality surveillance. As such, it can be employed to inform public health responses to the drug overdose epidemic in near-real time as opposed to several weeks following events.
Journal Article
Testing for Multisided Platform Effects in Antitrust Market Definition
2017
Given myriad business practices and conditions, establishing certain antitrust harms requires context. This context often comes from framing the effects of the challenged conduct against the backdrop of some relevant market. In particular, a challenged practice's anticompetitive impact may be outsized in a smaller market but insignificant in a larger one. For instance, the impact of a merger of two firms might be major if their combination captures 80 percent of a smaller market but relatively minor if that same combination represents only 10 percent of a larger market. In the latter, the combination is a drop in the bucket, while in the former it is a tidal wave. Plaintiffs thus have incentives to plead narrower relevant markets while defendants prefer broader ones. Yet this process of defining the relevant market can be highly technical, thrusting on judges the task of reining in increasingly complex economic and statistical analyses.
Journal Article
Cancer-associated IDH1 mutations produce 2-hydroxyglutarate
by
Gross, Stefan
,
Driggers, Edward M.
,
Prins, Robert M.
in
Alpha hydroxy acids
,
AMINO ACIDS
,
ARGININE
2009
Mutations in the enzyme cytosolic isocitrate dehydrogenase 1 (IDH1) are a common feature of a major subset of primary human brain cancers. These mutations occur at a single amino acid residue of the IDH1 active site, resulting in loss of the enzyme’s ability to catalyse conversion of isocitrate to α-ketoglutarate. However, only a single copy of the gene is mutated in tumours, raising the possibility that the mutations do not result in a simple loss of function. Here we show that cancer-associated IDH1 mutations result in a new ability of the enzyme to catalyse the NADPH-dependent reduction of α-ketoglutarate to
R
(-)-2-hydroxyglutarate (2HG). Structural studies demonstrate that when arginine 132 is mutated to histidine, residues in the active site are shifted to produce structural changes consistent with reduced oxidative decarboxylation of isocitrate and acquisition of the ability to convert α-ketoglutarate to 2HG. Excess accumulation of 2HG has been shown to lead to an elevated risk of malignant brain tumours in patients with inborn errors of 2HG metabolism. Similarly, in human malignant gliomas harbouring IDH1 mutations, we find markedly elevated levels of 2HG. These data demonstrate that the IDH1 mutations result in production of the onco-metabolite 2HG, and indicate that the excess 2HG which accumulates
in vivo
contributes to the formation and malignant progression of gliomas.
Role of 2-hydroxyglutarate in cancer
A high percentage of human glioblastomas has been found to harbour mutations in the metabolic enzyme cytosolic isocitrate dehydrogenase 1 (IDH1). The predominant R132H mutation is now shown to act as a gain-of-function mutation, enabling IDH1 to convert α-ketoglutarate to 2-hydroxyglutarate (2-HG). Human glioblastoma samples with
IDH1
mutations indeed contain elevated levels of 2-HG. Future work will be directed at understanding the mechanisms by which 2-HG can contribute to tumorigenesis.
Mutations in the enzyme cytosolic isocitrate dehydrogenase 1 (IDH1) are commonly found in glioblastomas, a major subset of primary human brain cancers. However, only a single copy of the gene is mutated, suggesting that the mutation does not result in a simple loss of function. Here, IDH1 mutations are shown to act in a gain-of-function manner, resulting in a new ability of the enzyme to catalyse α-ketoglutarate to
R
(-)-2-hydroxyglutarate, an onco-metabolite.
Journal Article