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1.
Front Cell Dev Biol ; 11: 1328806, 2023.
Article in English | MEDLINE | ID: mdl-38155837

ABSTRACT

Genomic imprinting is an epigenetic process whereby genes are monoallelically expressed in a parent-of-origin-specific manner. Imprinted genes are frequently found clustered in the genome, likely illustrating their need for both shared regulatory control and functional inter-dependence. The Dlk1-Dio3 domain is one of the largest imprinted clusters. Genes in this region are involved in development, behavior, and postnatal metabolism: failure to correctly regulate the domain leads to Kagami-Ogata or Temple syndromes in humans. The region contains many of the hallmarks of other imprinted domains, such as long non-coding RNAs and parental origin-specific CTCF binding. Recent studies have shown that the Dlk1-Dio3 domain is exquisitely regulated via a bipartite imprinting control region (ICR) which functions differently on the two parental chromosomes to establish monoallelic expression. Furthermore, the Dlk1 gene displays a selective absence of imprinting in the neurogenic niche, illustrating the need for precise dosage modulation of this domain in different tissues. Here, we discuss the following: how differential epigenetic marks laid down in the gametes cause a cascade of events that leads to imprinting in the region, how this mechanism is selectively switched off in the neurogenic niche, and why studying this imprinted region has added a layer of sophistication to how we think about the hierarchical epigenetic control of genome function.

2.
JAMA Pediatr ; 177(6): 644-646, 2023 06 01.
Article in English | MEDLINE | ID: mdl-37093591

ABSTRACT

This diagnostic study describes a dog screening program used to identify COVID-19 infections among schoolchildren.


Subject(s)
COVID-19 , Humans , Dogs , Animals , COVID-19/diagnosis , Schools , California/epidemiology , Pilot Projects
3.
Elife ; 122023 03 14.
Article in English | MEDLINE | ID: mdl-36916665

ABSTRACT

In mouse and human, genes subjected to genomic imprinting have been shown to function in development, behavior, and post-natal adaptations. Failure to correctly imprint genes in human is associated with developmental syndromes, adaptive, and metabolic disorders during life as well as numerous forms of cancer. In recent years researchers have turned to RNA-seq technologies applied to reciprocal hybrid strains of mice to identify novel imprinted genes, causing a threefold increase in genes reported as having a parental origin-specific expression bias. The functional relevance of parental origin-specific expression bias is not fully appreciated especially since many are reported with only minimal parental bias (e.g. 51:49). Here, we present an in-depth meta-analysis of previously generated RNA-seq data and show that the methods used to generate and analyze libraries greatly influence the calling of allele-specific expression. Validation experiments show that most novel genes called with parental-origin-specific allelic bias are artefactual, with the mouse strain contributing a larger effect on expression biases than parental origin. Of the weak novel genes that do validate, most are located at the periphery of known imprinted domains, suggesting they may be affected by local allele- and tissue-specific conformation. Together these findings highlight the need for robust tools, definitions, and validation of putative imprinted genes to provide meaningful information within imprinting databases and to understand the functional and mechanistic implications of the process.


Subject(s)
Gene Expression Profiling , Genomic Imprinting , Humans , Animals , Mice , Gene Expression , Gene Expression Profiling/methods , Alleles , DNA Methylation
4.
Nat Commun ; 13(1): 4391, 2022 07 29.
Article in English | MEDLINE | ID: mdl-35906226

ABSTRACT

Mammalian parental imprinting represents an exquisite form of epigenetic control regulating the parent-specific monoallelic expression of genes in clusters. While imprinting perturbations are widely associated with developmental abnormalities, the intricate regional interplay between imprinted genes makes interpreting the contribution of gene dosage effects to phenotypes a challenging task. Using mouse models with distinct deletions in an intergenic region controlling imprinting across the Dlk1-Dio3 domain, we link changes in genetic and epigenetic states to allelic-expression and phenotypic outcome in vivo. This determined how hierarchical interactions between regulatory elements orchestrate robust parent-specific expression, with implications for non-imprinted gene regulation. Strikingly, flipping imprinting on the parental chromosomes by crossing genotypes of complete and partial intergenic element deletions rescues the lethality of each deletion on its own. Our work indicates that parental origin of an epigenetic state is irrelevant as long as appropriate balanced gene expression is established and maintained at imprinted loci.


Subject(s)
Chromosomes , Genomic Imprinting , Alleles , Animals , DNA Methylation/genetics , DNA, Intergenic , Gene Dosage , Genomic Imprinting/genetics , Mammals/genetics , Mice
5.
PLoS Genet ; 18(4): e1010186, 2022 04.
Article in English | MEDLINE | ID: mdl-35482825

ABSTRACT

At interphase, de-condensed chromosomes have a non-random three-dimensional architecture within the nucleus, however, little is known about the extent to which nuclear organisation might influence expression or vice versa. Here, using imprinting as a model, we use 3D RNA- and DNA-fluorescence-in-situ-hybridisation in normal and mutant mouse embryonic stem cell lines to assess the relationship between imprinting control, gene expression and allelic distance from the nuclear periphery. We compared the two parentally inherited imprinted domains at the Dlk1-Dio3 domain and find a small but reproducible trend for the maternally inherited domain to be further away from the periphery however we did not observe an enrichment of inactive alleles in the immediate vicinity of the nuclear envelope. Using Zfp57KO ES cells, which harbour a paternal to maternal epigenotype switch, we observe that expressed alleles are significantly further away from the nuclear periphery. However, within individual nuclei, alleles closer to the periphery are equally likely to be expressed as those further away. In other words, absolute position does not predict expression. Taken together, this suggests that whilst stochastic activation can cause subtle shifts in localisation for this locus, there is no dramatic relocation of alleles upon gene activation. Our results suggest that transcriptional activity, rather than the parent-of-origin, defines subnuclear localisation at an endogenous imprinted domain.


Subject(s)
Calcium-Binding Proteins , Genomic Imprinting , Iodide Peroxidase , Membrane Proteins , Alleles , Animals , Calcium-Binding Proteins/genetics , Calcium-Binding Proteins/metabolism , Cell Nucleus/genetics , Cell Nucleus/metabolism , Embryonic Stem Cells/cytology , Embryonic Stem Cells/metabolism , Gene Expression , Genomic Imprinting/genetics , Iodide Peroxidase/genetics , Iodide Peroxidase/metabolism , Membrane Proteins/genetics , Membrane Proteins/metabolism , Mice , Parents
6.
J Gen Intern Med ; 36(12): 3665-3671, 2021 12.
Article in English | MEDLINE | ID: mdl-34545472

ABSTRACT

BACKGROUND: Prior studies using aggregated data suggest that better care coordination is associated with higher performance on measures of clinical care process; it is unclear whether this relationship reflects care coordination activities of health plans or physician practices. OBJECTIVE: Estimate within-plan relationships between beneficiary-reported care coordination measures and HEDIS measures of clinical process for the same individuals. DESIGN: Mixed-effect regression models in cross-sectional data. PARTICIPANTS: 2013 Medicare Advantage CAHPS respondents (n=152,069) with care coordination items linked to independently collected HEDIS data on clinical processes. MAIN MEASURES: Care coordination measures assessed follow-up, whether doctors had medical records during visits, whether doctors discussed medicines being taken, how informed doctors seemed about specialist care, and help received with managing care among different providers. HEDIS measures included mammography, colorectal cancer screening, cardiovascular LDL-C screening, controlling blood pressure, 5 diabetes care measures (LDL-C screening, retinal eye exam, nephropathy, blood sugar/HbA1c <9%, LCL-C<100 mg/dL), glaucoma screening in older adults, BMI assessment, osteoporosis management for women with a fracture, and rheumatoid arthritis therapy. KEY RESULTS: For 9 of the 13 HEDIS measures, within health plans, beneficiaries who reported better care coordination also received better clinical care (p<0.05) and none of the associations went in the opposite direction; HEDIS differences between those with excellent and poor coordination exceeded 5 percentage points for 7 measures. Nine measures had positive associations (breast cancer screening, colorectal cancer screening, cardiovascular care LDL-C screening, 4 of 5 diabetes care measures, osteoporosis management, and rheumatoid arthritis therapy). CONCLUSIONS: Within health plans, beneficiaries who report better care coordination also received higher-quality clinical care, particularly for care processes that entail organizing patient care activities and sharing information among different healthcare providers. These results extend prior research showing that health plans with better beneficiary-reported care coordination achieved higher HEDIS performance scores.


Subject(s)
Medicare Part C , Aged , Cross-Sectional Studies , Female , Humans , Patient Care , Patient Reported Outcome Measures , Quality of Health Care , United States/epidemiology
7.
Womens Health Issues ; 30(6): 477-483, 2020.
Article in English | MEDLINE | ID: mdl-32994130

ABSTRACT

BACKGROUND: Medicare beneficiaries annually select fee-for-service Medicare or a private Medicare insurance (managed care) plan; information about plan performance on quality measures can inform their decisions. Although there is drill-down information available regarding quality variation by race and ethnicity, there remains a dearth of evidence regarding the extent to which care varies by other key beneficiary characteristics, such as gender. We measured gender differences for six patient experience measures and how gender gaps differ across Medicare plans. METHODS: We used data from 300,979 respondents to the 2015-2016 Medicare Advantage Consumer Assessment of Healthcare Providers and Systems surveys. We fit case mix-adjusted linear mixed-effects models to estimate gender differences and evaluate heterogeneity in differences across health plans. RESULTS: Nationally, women's experiences were better than men's (p < .05) by 1 percentage point on measures involving interactions with administrative staff (+1.6 percentage point for customer service) and timely access to care (+1.1 percentage point for getting care quickly), but worse on a measure that may involve negotiation with physicians (getting needed care). Gender gaps varied across plans, particularly for getting care quickly and getting needed care, where plan-level differences of up to 5 to 6 percentage points were observed. CONCLUSIONS: Although the average national differences in patient experience by gender were generally small, gender gaps were larger in some health plans and for specific measures. This finding indicates opportunities for health plans with larger gender gaps to implement quality improvement efforts.


Subject(s)
Medicare Part C , Aged , Female , Humans , Male , Managed Care Programs , Patient Outcome Assessment , Sex Characteristics , Sex Factors , United States
8.
Reprod Fertil Dev ; 31(7): 1203-1218, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30615843

ABSTRACT

Genomic imprinting is a process that causes genes to be expressed according to their parental origin. Imprinting appears to have evolved gradually in two of the three mammalian subclasses, with no imprinted genes yet identified in prototheria and only six found to be imprinted in marsupials to date. By interrogating the genomes of eutherian suborders, we determine that imprinting evolved at the majority of eutherian specific genes before the eutherian radiation. Theories considering the evolution of imprinting often relate to resource allocation and recently consider maternal-offspring interactions more generally, which, in marsupials, places a greater emphasis on lactation. In eutherians, the imprint memory is retained at least in part by zinc finger protein 57 (ZFP57), a Kruppel associated box (KRAB) zinc finger protein that binds specifically to methylated imprinting control regions. Some imprints are less dependent on ZFP57invivo and it may be no coincidence that these are the imprints that are found in marsupials. Because marsupials lack ZFP57, this suggests another more ancestral protein evolved to regulate imprints in non-eutherian subclasses, and contributes to imprinting control in eutherians. Hence, understanding the mechanisms acting at imprinting control regions across mammals has the potential to provide valuable insights into our understanding of the origins and evolution of genomic imprinting.


Subject(s)
DNA Methylation , Genomic Imprinting , Mammals/genetics , Animals , Evolution, Molecular , Marsupialia/genetics
9.
Health Serv Res ; 54(1): 5-12, 2019 02.
Article in English | MEDLINE | ID: mdl-30467826

ABSTRACT

OBJECTIVE: Spanish-preferring Medicare beneficiaries are underrepresented in national patient experience surveys. We test a method for improving their representation via higher response rates. DATA SOURCES/STUDY SETTING: 2009-2010 Medicare CAHPS surveys; Medicare population. STUDY DESIGN: We used surname and address to predict Spanish-language preference for a national sample of 177 139 beneficiaries. We randomized half of the 10 000 non-Puerto Rico beneficiaries with the highest predicted probabilities of Spanish preference (>10 percent) to bilingual mailings (intervention) and half to standard English-only mailings (control). DATA COLLECTION: Medicare CAHPS Survey data were collected through mail surveys with telephone follow-up of nonrespondents. PRINCIPAL FINDINGS: Mail response rate was higher for intervention (28.7 percent) than control (23.9 percent) (P < 0.0001); phone response rates among mail nonrespondents were similar in intervention and control arms (15.8 percent vs 15.7 percent, P = 0.90). Targeted bilingual mailings induced 6.5 percent of those who would not have responded to respond by mail and 54.0 percent of those who would have responded in English to respond in Spanish. Beneficiaries with greater Spanish probabilities showed greater increases in response rates, a higher proportion of responses in Spanish, and lower control response rates among. CONCLUSIONS: Targeted bilingual mailing of mixed-mode surveys using commonly available surname and address information can efficiently increase representation of this underrepresented group.


Subject(s)
Health Care Surveys/statistics & numerical data , Hispanic or Latino/statistics & numerical data , Medicare/organization & administration , Postal Service/statistics & numerical data , Female , Healthcare Disparities/organization & administration , Humans , Male , United States
10.
Genome Res ; 2018 01 24.
Article in English | MEDLINE | ID: mdl-29367313

ABSTRACT

Approximately half the mammalian genome is composed of repetitive sequences, and accumulating evidence suggests that some may have an impact on genome function. Here, we characterized a large array class of repeats of long-interspersed elements (LINE-1). Although widely distributed in mammals, locations of such arrays are species specific. Using targeted deletion, we asked whether a 170-kb LINE-1 array located at a mouse imprinted domain might function as a modulator of local transcriptional control. The LINE-1 array is lamina associated in differentiated ES cells consistent with its AT-richness, and although imprinting occurs both proximally and distally to the array, active LINE-1 transcripts within the tract are biallelically expressed. Upon deletion of the array, no perturbation of imprinting was observed, and abnormal phenotypes were not detected in maternal or paternal heterozygous or homozygous mutant mice. The array does not shield nonimprinted genes in the vicinity from local imprinting control. Reduced neural expression of protein-coding genes observed upon paternal transmission of the deletion is likely due to the removal of a brain-specific enhancer embedded within the LINE array. Our findings suggest that presence of a 170-kb LINE-1 array reflects the tolerance of the site for repeat insertion rather than an important genomic function in normal development.

11.
Health Aff (Millwood) ; 35(3): 456-63, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26953300

ABSTRACT

Since 2006, Medicare beneficiaries have been able to obtain prescription drug coverage through standalone prescription drug plans or their Medicare Advantage (MA) health plan, options exercised in 2015 by 72 percent of beneficiaries. Using data from community-dwelling Medicare beneficiaries older than age sixty-four in 700 plans surveyed from 2007 to 2014, we compared beneficiaries' assessments of Medicare prescription drug coverage when provided by standalone plans or integrated into an MA plan. Beneficiaries in standalone plans consistently reported less positive experiences with prescription drug plans (ease of getting medications, getting coverage information, and getting cost information) than their MA counterparts. Because MA plans are responsible for overall health care costs, they might have more integrated systems and greater incentives than standalone prescription drug plans to provide enrollees medications and information effectively, including, since 2010, quality bonus payments to these MA plans under provisions of the Affordable Care Act.


Subject(s)
Drug Prescriptions/economics , Insurance, Pharmaceutical Services/economics , Medicare Part C/economics , Medicare Part D/economics , Surveys and Questionnaires , Age Factors , Aged , Aged, 80 and over , Databases, Factual , Drug Prescriptions/statistics & numerical data , Female , Health Expenditures , Humans , Insurance Coverage/economics , Male , Managed Care Programs/economics , Managed Care Programs/statistics & numerical data , Patient Satisfaction/statistics & numerical data , Retrospective Studies , Sex Factors , United States
12.
Chem Biol Interact ; 259(Pt B): 327-331, 2016 Nov 25.
Article in English | MEDLINE | ID: mdl-26892220

ABSTRACT

Carboxylesterases (CE) are members of the esterase family of enzymes, and as their name suggests, they are responsible for the hydrolysis of carboxylesters into the corresponding alcohol and carboxylic acid. To date, no endogenous CE substrates have been identified and as such, these proteins are thought to act as a mechanism to detoxify ester-containing xenobiotics. As a consequence, they are expressed in tissues that might be exposed to such agents (lung and gut epithelia, liver, kidney, etc.). CEs demonstrate very broad substrate specificities and can hydrolyze compounds as diverse as cocaine, oseltamivir (Tamiflu), permethrin and irinotecan. In addition, these enzymes are irreversibly inhibited by organophosphates such as Sarin and Tabun. In this overview, we will compare and contrast the two human enzymes that have been characterized, and evaluate the biology of the interaction of these proteins with organophosphates (principally nerve agents).


Subject(s)
Carboxylic Ester Hydrolases/metabolism , Animals , Carboxylic Ester Hydrolases/chemistry , Humans , Inactivation, Metabolic , Models, Molecular , Organophosphates/metabolism , Substrate Specificity
13.
Development ; 142(14): 2425-30, 2015 Jul 15.
Article in English | MEDLINE | ID: mdl-26138477

ABSTRACT

The paternally expressed imprinted retrotransposon-like 1 (Rtl1) is a retrotransposon-derived gene that has evolved a function in eutherian placentation. Seven miRNAs, including miR-127, are processed from a maternally expressed antisense Rtl1 transcript (Rtl1as) and regulate Rtl1 levels through RNAi-mediated post-transcriptional degradation. To determine the relative functional role of Rtl1as miRNAs in Rtl1 dosage, we generated a mouse specifically deleted for miR-127. The miR-127 knockout mice exhibit placentomegaly with specific defects within the labyrinthine zone involved in maternal-fetal nutrient transfer. Although fetal weight is unaltered, specific Rtl1 transcripts and protein levels are increased in both the fetus and placenta. Phenotypic analysis of single (ΔmiR-127/Rtl1 or miR-127/ΔRtl1) and double (ΔmiR-127/ΔRtl1) heterozygous miR-127- and Rtl1-deficient mice indicate that Rtl1 is the main target gene of miR-127 in placental development. Our results demonstrate that miR-127 is an essential regulator of Rtl1, mediated by a trans-homologue interaction between reciprocally imprinted genes on the maternally and paternally inherited chromosomes.


Subject(s)
Gene Expression Regulation, Developmental , MicroRNAs/metabolism , Placenta/physiology , Pregnancy Proteins/metabolism , Animals , Chromosomes/metabolism , Chromosomes/ultrastructure , Crosses, Genetic , Exons , Female , Gene Deletion , Genomic Imprinting , Heterozygote , Mice , Mice, Inbred C57BL , Mice, Knockout , Multigene Family , Phenotype , Placenta/metabolism , Placentation/genetics , Pregnancy , RNA Interference
14.
Health Serv Res ; 50(6): 1829-49, 2015 Dec.
Article in English | MEDLINE | ID: mdl-25757356

ABSTRACT

OBJECTIVE: To examine how similar racial/ethnic disparities in clinical quality (Healthcare Effectiveness Data and Information Set [HEDIS]) and patient experience (Consumer Assessment of Healthcare Providers and Systems [CAHPS]) measures are for different measures within Medicare Advantage (MA) plans. DATA SOURCES/STUDY SETTING: 5.7 million/492,495 MA beneficiaries with 2008-2009 HEDIS/CAHPS data. STUDY DESIGN: Binomial (HEDIS) and linear (CAHPS) hierarchical mixed models generated contract estimates for HEDIS/CAHPS measures for Hispanics, blacks, Asian-Pacific Islanders, and whites. We examine the correlation of within-plan disparities for HEDIS and CAHPS measures across measures. PRINCIPAL FINDINGS: Plans with disparities for a given minority group (vs. whites) for a particular measure have a moderate tendency for similar disparities for other measures of the same type (mean r = 0.51/.21 and 53/34 percent positive and statistically significant for CAHPS/HEDIS). This pattern holds to a lesser extent for correlations of CAHPS disparities and HEDIS disparities (mean r = 0.05/0.14/0.23 and 4.4/5.6/4.4 percent) positive and statistically significant for blacks/Hispanics/API. CONCLUSIONS: Similarities in CAHPS and HEDIS disparities across measures might reflect common structural factors, such as language services or provider incentives, affecting several measures simultaneously. Health plan structural changes might reduce disparities across multiple measures.


Subject(s)
Ethnicity/statistics & numerical data , Healthcare Disparities/statistics & numerical data , Medicare Part C/statistics & numerical data , Quality of Health Care/statistics & numerical data , Racial Groups/statistics & numerical data , Adolescent , Adult , Black or African American , Age Factors , Aged , Aged, 80 and over , Asian , Benchmarking/statistics & numerical data , Educational Status , Female , Health Services Accessibility/statistics & numerical data , Health Status , Hispanic or Latino , Humans , Male , Mental Health , Middle Aged , Patient Satisfaction , Sex Factors , Time Factors , United States , Young Adult
15.
Annu Rev Genomics Hum Genet ; 15: 93-126, 2014.
Article in English | MEDLINE | ID: mdl-24898037

ABSTRACT

Genomic imprinting is an epigenetic process causing expression of a subset of genes in a parent-of-origin-specific manner. Among vertebrates, only therian mammals have been demonstrated to imprint, indicating that placentation and imprinting arose at similar time points in evolution and that imprinting may be involved in key mammal-specific processes. However, although several theories have been posited to explain the evolution of imprinting, each has shortcomings and none fully explains the wide variety of genes regulated by imprinting. In this review, we catalog the phenotypes associated with genetic mutation and overexpression at particular imprinted loci in order to consider the wide impact of imprinted genes on development. In addition to the well-described roles of imprinted genes in prenatal growth and placentation, more recent data emphasize that imprinted genes are critical for specific aspects of postnatal mammalian development involving adaptive processes, metabolism, and behavior.


Subject(s)
Genome , Genomic Imprinting/genetics , Mutation/genetics , Animals , Chromosomes/genetics , Gene Expression Regulation, Developmental , Humans , Mice , Models, Animal , Phenotype
16.
J Clin Invest ; 123(5): 2169-82, 2013 May.
Article in English | MEDLINE | ID: mdl-23543057

ABSTRACT

Large regions of recurrent genomic loss are common in cancers; however, with a few well-characterized exceptions, how they contribute to tumor pathogenesis remains largely obscure. Here we identified primate-restricted imprinting of a gene cluster on chromosome 20 in the region commonly deleted in chronic myeloid malignancies. We showed that a single heterozygous 20q deletion consistently resulted in the complete loss of expression of the imprinted genes L3MBTL1 and SGK2, indicative of a pathogenetic role for loss of the active paternally inherited locus. Concomitant loss of both L3MBTL1 and SGK2 dysregulated erythropoiesis and megakaryopoiesis, 2 lineages commonly affected in chronic myeloid malignancies, with distinct consequences in each lineage. We demonstrated that L3MBTL1 and SGK2 collaborated in the transcriptional regulation of MYC by influencing different aspects of chromatin structure. L3MBTL1 is known to regulate nucleosomal compaction, and we here showed that SGK2 inactivated BRG1, a key ATP-dependent helicase within the SWI/SNF complex that regulates nucleosomal positioning. These results demonstrate a link between an imprinted gene cluster and malignancy, reveal a new pathogenetic mechanism associated with acquired regions of genomic loss, and underline the complex molecular and cellular consequences of "simple" cancer-associated chromosome deletions.


Subject(s)
Chromosome Deletion , Chromosomes, Human, Pair 20 , Gene Expression Regulation , Genomic Imprinting , Alleles , Animals , Cell Lineage , Chromosomal Proteins, Non-Histone/genetics , Female , Gene Silencing , Heterozygote , Humans , Immediate-Early Proteins/genetics , Macaca , Macropodidae , Male , Models, Genetic , Multigene Family , Myeloproliferative Disorders/genetics , Neoplasms/genetics , Protein Serine-Threonine Kinases/genetics , Repressor Proteins , Transcription, Genetic , Tumor Suppressor Proteins
17.
J Am Geriatr Soc ; 61(3): 407-12, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23379270

ABSTRACT

OBJECTIVES: To compare reports about care experiences of individuals who died within 1 year of survey with reports of those who did not. DESIGN: Medicare Advantage (MA) Consumer Assessment of Healthcare Providers and Systems (CAHPS) surveys asked about care experiences. Survey completion dates were linked to Social Security Administration death records to identify enrollees dying within 1 year of survey completion. Propensity-score weighting combined with regression-based case-mix adjustment was used to compare these individuals' experiences with experiences of those who were alive 1 year later. SETTING: Nationally representative sample of MA enrollees. PARTICIPANTS: Four hundred two thousand five hundred ninety-three MA enrollees responding to 2008 and 2009 CAHPS Surveys. MEASUREMENTS: Outcomes were five care ratings (plan, prescription drug coverage, doctor, specialists, care) and five composite measures of care (getting needed care, getting care quickly, doctor communication, getting drugs, getting drug information). Analyses were adjusted for age, sex, race and ethnicity, education, Medicaid status, geographic region, and several health status measures. RESULTS: Twelve thousand one hundred two enrollees (3%) died within 1 year of survey completion (near-end-of-life group). Those enrollees reported slightly better experiences than other enrollees with respect to getting care quickly (+2%, P < .001) and gave slightly higher ratings for their plans (+1%, P = .02) and prescription drug coverage (+1%, P < .001). There were no measures of participant experience for which the near-end-of-life group reported worse experiences than other enrollees. CONCLUSION: Contrary to analyses based on retrospective reports from surviving relatives after an individual's death, MA enrollees' reports about care within 1 year of death were as good as or better than reports of other MA enrollees. Future research might investigate whether results are similar in other Medicare populations.


Subject(s)
Chronic Disease/therapy , Managed Care Programs , Medicare Part C , Patient Satisfaction , Terminal Care , Adolescent , Adult , Aged , Aged, 80 and over , Diagnosis-Related Groups , Female , Health Care Surveys , Humans , Linear Models , Male , Propensity Score , United States
18.
J Nat Prod ; 76(1): 36-44, 2013 Jan 25.
Article in English | MEDLINE | ID: mdl-23286284

ABSTRACT

The roots of Salvia miltiorrhiza ("Danshen") are used in traditional Chinese medicine for the treatment of numerous ailments including cardiovascular disease, hypertension, and ischemic stroke. Extracts of S. miltiorrhiza roots in the formulation "Compound Danshen Dripping Pill" are undergoing clinical trials in the United States. To date, the active components of this material have not been conclusively identified. We have determined that S. miltiorrhiza roots contain potent human carboxylesterase (CE) inhibitors, due to the presence of tanshinones. K(i) values in the nM range were determined for inhibition of both the liver and intestinal CEs. As CEs hydrolyze clinically used drugs, the ability of tanshinones and S. miltiorrhiza root extracts to modulate the metabolism of the anticancer prodrug irinotecan (CPT-11) was assessed. Our results indicate that marked inhibition of human CEs occurs following incubation with both pure compounds and crude material and that drug hydrolysis is significantly reduced. Consequently, a reduction in the cytotoxicity of irinotecan is observed following dosing with either purified tanshinones or S. miltiorrhiza root extracts. It is concluded that remedies containing tanshinones should be avoided when individuals are taking esterified agents and that patients should be warned of the potential drug-drug interaction that may occur with this material.


Subject(s)
Abietanes/isolation & purification , Abietanes/pharmacology , Camptothecin/analogs & derivatives , Carboxylesterase/antagonists & inhibitors , Drugs, Chinese Herbal/pharmacology , Phenanthrolines/pharmacology , Salvia miltiorrhiza/chemistry , Abietanes/chemistry , Abietanes/pharmacokinetics , Algorithms , Camptothecin/chemistry , Camptothecin/pharmacology , Clinical Trials, Phase I as Topic , Herb-Drug Interactions , Humans , Irinotecan , Medicine, Chinese Traditional , Molecular Structure , Plant Roots/chemistry
19.
Chem Biol Interact ; 203(1): 226-30, 2013 Mar 25.
Article in English | MEDLINE | ID: mdl-23123248

ABSTRACT

Carboxylesterases (CEs) are ubiquitously expressed proteins that are responsible for the detoxification of xenobiotics. They tend to be expressed in tissues likely to be exposed to such agents (e.g., lung and gut epithelia, liver) and can hydrolyze numerous agents, including many clinically used drugs. Due to the considerable structural similarity between cholinesterases (ChE) and CEs, we have assessed the ability of a series of ChE inhibitors to modulate the activity of the human liver (hCE1) and the human intestinal CE (hiCE) isoforms. We observed inhibition of hCE1 and hiCE by carbamate-containing small molecules, including those used for the treatment of Alzheimer's disease. For example, rivastigmine resulted in greater than 95% inhibition of hiCE that was irreversible under the conditions used. Hence, the administration of esterified drugs, in combination with these carbamates, may inadvertently result in decreased hydrolysis of the former, thereby limiting their efficacy. Therefore drug:drug interactions should be carefully evaluated in individuals receiving ChE inhibitors.


Subject(s)
Carboxylesterase/antagonists & inhibitors , Carboxylic Ester Hydrolases/antagonists & inhibitors , Cholinesterase Inhibitors/pharmacology , Carboxylesterase/chemistry , Carboxylesterase/genetics , Carboxylic Ester Hydrolases/chemistry , Carboxylic Ester Hydrolases/genetics , Drug Interactions , Humans , Intestines/enzymology , Kinetics , Liver/enzymology , Models, Molecular , Phenylcarbamates/pharmacology , Physostigmine/analogs & derivatives , Physostigmine/pharmacology , Recombinant Proteins/antagonists & inhibitors , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Rivastigmine
20.
Bioorg Med Chem ; 19(15): 4635-43, 2011 Aug 01.
Article in English | MEDLINE | ID: mdl-21733699

ABSTRACT

Carboxylesterases (CE) are ubiquitous enzymes found in both human and animal tissues and are responsible for the metabolism of xenobiotics. This includes numerous natural products, as well as a many clinically used drugs. Hence, the activity of these agents is likely dependent upon the levels and location of CE expression. We have recently identified benzil is a potent inhibitor of mammalian CEs, and in this study, we have assessed the ability of analogues of this compound to inhibit these enzymes. Three different classes of molecules were assayed: one containing different atoms vicinal to the carbonyl carbon atom and the benzene ring [PhXC(O)C(O)XPh, where X=CH2, CHBr, N, S, or O]; a second containing a panel of alkyl 1,2-diones demonstrating increasing alkyl chain length; and a third consisting of a series of 1-phenyl-2-alkyl-1,2-diones. In general, with the former series of molecules, heteroatoms resulted in either loss of inhibitory potency (when X=N), or conversion of the compounds into substrates for the enzymes (when X=S or O). However, the inclusion of a brominated methylene atom resulted in potent CE inhibition. Subsequent analysis with the alkyl diones [RC(O)C(O)R, where R ranged from CH3 to C8H17] and 1-phenyl-2-alkyl-1,2-diones [PhC(O)C(O)R where R ranged from CH3 to C6H13], demonstrated that the potency of enzyme inhibition directly correlated with the hydrophobicity (clogP) of the molecules. We conclude from these studies that that the inhibitory power of these 1,2-dione derivatives depends primarily upon the hydrophobicity of the R group, but also on the electrophilicity of the carbonyl group.


Subject(s)
Carboxylesterase/antagonists & inhibitors , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Animals , Carboxylesterase/metabolism , Cell Line , Cell Proliferation/drug effects , Enzyme Inhibitors/chemical synthesis , Ethane/chemical synthesis , Ethane/chemistry , Ethane/pharmacology , Humans , Inhibitory Concentration 50 , Molecular Dynamics Simulation
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