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1.
Cell ; 186(4): 715-731.e19, 2023 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-36754048

RESUMEN

Transgenerational epigenetic inheritance in mammals remains a debated subject. Here, we demonstrate that DNA methylation of promoter-associated CpG islands (CGIs) can be transmitted from parents to their offspring in mice. We generated DNA methylation-edited mouse embryonic stem cells (ESCs), in which CGIs of two metabolism-related genes, the Ankyrin repeat domain 26 and the low-density lipoprotein receptor, were specifically methylated and silenced. DNA methylation-edited mice generated by microinjection of the methylated ESCs exhibited abnormal metabolic phenotypes. Acquired methylation of the targeted CGI and the phenotypic traits were maintained and transmitted across multiple generations. The heritable CGI methylation was subjected to reprogramming in parental PGCs and subsequently reestablished in the next generation at post-implantation stages. These observations provide a concrete step toward demonstrating transgenerational epigenetic inheritance in mammals, which may have implications in our understanding of evolutionary biology as well as the etiology, diagnosis, and prevention of non-genetically inherited human diseases.


Asunto(s)
Metilación de ADN , Epigénesis Genética , Ratones , Humanos , Animales , Islas de CpG , Patrón de Herencia , Mamíferos/genética
2.
Immunity ; 54(7): 1561-1577.e7, 2021 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-34102100

RESUMEN

A common metabolic alteration in the tumor microenvironment (TME) is lipid accumulation, a feature associated with immune dysfunction. Here, we examined how CD8+ tumor infiltrating lymphocytes (TILs) respond to lipids within the TME. We found elevated concentrations of several classes of lipids in the TME and accumulation of these in CD8+ TILs. Lipid accumulation was associated with increased expression of CD36, a scavenger receptor for oxidized lipids, on CD8+ TILs, which also correlated with progressive T cell dysfunction. Cd36-/- T cells retained effector functions in the TME, as compared to WT counterparts. Mechanistically, CD36 promoted uptake of oxidized low-density lipoproteins (OxLDL) into T cells, and this induced lipid peroxidation and downstream activation of p38 kinase. Inhibition of p38 restored effector T cell functions in vitro, and resolution of lipid peroxidation by overexpression of glutathione peroxidase 4 restored functionalities in CD8+ TILs in vivo. Thus, an oxidized lipid-CD36 axis promotes intratumoral CD8+ T cell dysfunction and serves as a therapeutic avenue for immunotherapies.


Asunto(s)
Antígenos CD36/metabolismo , Linfocitos T CD8-positivos/metabolismo , Peroxidación de Lípido/fisiología , Lipoproteínas LDL/metabolismo , Neoplasias/metabolismo , Receptores Depuradores/metabolismo , Animales , Transporte Biológico/fisiología , Línea Celular Tumoral , Células HEK293 , Humanos , Leucocitos Mononucleares/metabolismo , Linfocitos Infiltrantes de Tumor/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Microambiente Tumoral/fisiología
3.
Nature ; 614(7949): 767-773, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36755096

RESUMEN

Cancers arise through the accumulation of genetic and epigenetic alterations that enable cells to evade telomere-based proliferative barriers and achieve immortality. One such barrier is replicative crisis-an autophagy-dependent program that eliminates checkpoint-deficient cells with unstable telomeres and other cancer-relevant chromosomal aberrations1,2. However, little is known about the molecular events that regulate the onset of this important tumour-suppressive barrier. Here we identified the innate immune sensor Z-DNA binding protein 1 (ZBP1) as a regulator of the crisis program. A crisis-associated isoform of ZBP1 is induced by the cGAS-STING DNA-sensing pathway, but reaches full activation only when associated with telomeric-repeat-containing RNA (TERRA) transcripts that are synthesized from dysfunctional telomeres. TERRA-bound ZBP1 oligomerizes into filaments on the outer mitochondrial membrane of a subset of mitochondria, where it activates the innate immune adapter protein mitochondrial antiviral-signalling protein (MAVS). We propose that these oligomerization properties of ZBP1 serve as a signal amplification mechanism, where few TERRA-ZBP1 interactions are sufficient to launch a detrimental MAVS-dependent interferon response. Our study reveals a mechanism for telomere-mediated tumour suppression, whereby dysfunctional telomeres activate innate immune responses through mitochondrial TERRA-ZBP1 complexes to eliminate cells destined for neoplastic transformation.


Asunto(s)
Replicación del ADN , Mitocondrias , Transducción de Señal , Telómero , Humanos , ADN/biosíntesis , ADN/genética , ADN/metabolismo , Mitocondrias/genética , Mitocondrias/metabolismo , Neoplasias/genética , Neoplasias/patología , ARN Largo no Codificante/biosíntesis , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Telómero/genética , Telómero/metabolismo , Interferones , Inmunidad Innata , Autofagia
4.
PLoS Genet ; 18(5): e1010234, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35639796

RESUMEN

Sprague Dawley (SD) rats are among the most widely used outbred laboratory rat populations. Despite this, the genetic characteristics of SD rats have not been clearly described, and SD rats are rarely used for experiments aimed at exploring genotype-phenotype relationships. In order to use SD rats to perform a genome-wide association study (GWAS), we collected behavioral data from 4,625 SD rats that were predominantly obtained from two commercial vendors, Charles River Laboratories and Harlan Sprague Dawley Inc. Using double-digest genotyping-by-sequencing (ddGBS), we obtained dense, high-quality genotypes at 291,438 SNPs across 4,061 rats. This genetic data allowed us to characterize the variation present in Charles River vs. Harlan SD rats. We found that the two populations are highly diverged (FST > 0.4). Furthermore, even for rats obtained from the same vendor, there was strong population structure across breeding facilities and even between rooms at the same facility. We performed multiple separate GWAS by fitting a linear mixed model that accounted for population structure and using meta-analysis to jointly analyze all cohorts. Our study examined Pavlovian conditioned approach (PavCA) behavior, which assesses the propensity for rats to attribute incentive salience to reward-associated cues. We identified 46 significant associations for the various metrics used to define PavCA. The surprising degree of population structure among SD rats from different sources has important implications for their use in both genetic and non-genetic studies.


Asunto(s)
Estudio de Asociación del Genoma Completo , Recompensa , Animales , Condicionamiento Clásico , Motivación , Ratas , Ratas Sprague-Dawley
5.
J Gen Intern Med ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38965201

RESUMEN

BACKGROUND: Women are the fastest growing veteran group in the US and the number of women veterans (WVs) with cancer is rising; however, little is known about this population. Cancer care for WVs is complex and it is essential to understand their unique needs and care coordination challenges to provide evidence-based care. The purpose of this review is to map the quantity, distribution, and characteristics of literature describing cancer and its treatment among WVs. METHODS: We searched MEDLINE (via PubMed), Embase (Elsevier), and Web of Science Core Collection (Clarivate) from inception through January, 2024. Publications were eligible that reported gender-specific data on any aspect of cancer care among WVs. Data was abstracted by a single investigator with over-reading. RESULTS: Forty-six reports were included; 44 were observational and 19 had a women-only sample. There were no interventional reports and no qualitative reports had a patient sample. Breast cancer was the most commonly addressed (n = 19). There were six additional reports on sex-specific cancers. Many reports used large VA databases or previous trial data, creating the potential for patient overlap between reports. Among VA-specific areas of interest, only three reports evaluated the potential implications of racial differences and only two included a transgender population. No reports examined the effects of toxic exposures on cancer. Within the NCI Cancer Control Continuum, crosscutting areas were more commonly represented; over half (25) of the reports addressed epidemiology. There were few reports on focus areas and little overlap between focus and crosscutting areas. DISCUSSION: Existing literature provides an inadequate understanding of the population of WVs with cancer. There is scant information regarding the population of WVs with cancer, their care preferences or experiences, or how to best identify and address unmet healthcare needs. It is imperative to expand research to provide evidence-based care for this population.

6.
Pancreatology ; 23(2): 187-191, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36585282

RESUMEN

Using the ongoing NIDDK-funded multicenter randomized clinical trial, Sphincterotomy for Acute Recurrent Pancreatitis (SHARP) as an example, this article discusses the rationale and key aspects of study design that need to be considered when conducting a clinical trial of endoscopic therapy in acute pancreatitis. SHARP, the first trial using a sham ERCP in the placebo group, is designed to address a decades long controversy in clinical pancreatology, i.e. whether minor papilla sphincterotomy benefits patients with idiopathic acute recurrent pancreatitis who also have pancreas divisum. Although the trial has already enrolled and randomized over 5 times the number of subjects enrolled in the only randomized trial in this area published in 1992 (107 vs. 19), recruitment has been challenging and we are at ∼46% of target recruitment. The review discusses the challenges in the execution of the trial and strategies the SHARP team has used to address these, which investigators planning or considering treatment trials in pancreatitis may find helpful. It will also inform the general gastroenterologists the importance of discussing and referring potentially eligible subjects to centers participating in clinical trials. Developing evidence-based treatment will provide a solid scientific basis for physicians to recommend evidence-based treatments for pancreatitis.


Asunto(s)
Pancreatitis Crónica , Esfinterotomía , Humanos , Páncreas , Colangiopancreatografia Retrógrada Endoscópica , Enfermedad Aguda , Esfinterotomía Endoscópica , Recurrencia , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto
7.
BMC Med Inform Decis Mak ; 23(1): 208, 2023 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-37814248

RESUMEN

BACKGROUND: Clinical events suggestive of nutrition care found in electronic health records (EHRs) are rarely explored for their associations with hypertension outcomes. METHODS: Longitudinal analysis using structured EHR data from primary care visits at a health system in the US from December 2017-December 2020 of adult patients with hypertension (n = 4,237) tested for associations between last visit blood pressure (BP) control (≤ 140 Systolic BP and ≤ 90 Diastolic BP) and ≥ 1 nutrition care clinical event operationalized as (overweight or obesity (BMI > 25 or 30, respectively) diagnoses, preventive care visits, or provision of patient education materials (PEM)). Descriptive statistics and longitudinal targeted maximum likelihood estimation (LTMLE) models were conducted to explore average treatment effects (ATE) of timing and dose response from these clinical events on blood pressure control overall and by race. RESULTS: The median age was 62 years, 29% were male, 52% were Black, 25% were from rural areas and 50% had controlled BP at baseline. Annual documentation of overweight/obesity diagnoses ranged 3.0-7.8%, preventive care visits ranged 6.2-15.7%, and PEM with dietary and hypertension content were distributed to 8.5-28.8% patients. LTMLE models stratified by race showed differences in timing, dose, and type of nutrition care. Black patients who had nutrition care in Year 3 only compared to none had lower odds for BP control (ATE -0.23, 95% CI: -0.38,-0.08, p = 0.003), preventive visits in the last 2 years high higher odds for BP control (ATE 0.31, 95% CI: 0.07,0.54, p = 0.01), and early or late PEMs had lower odds for BP control (ATE -0.08, 95% CI: -0.15,-0.01, p = 0.03 and ATE -0.23, 95% CI: -0.41,-0.05, p = 0.01, respectively). CONCLUSIONS: In this study, clinical events suggestive of nutrition care are significantly associated with BP control, but are infrequent and effects differ by type, timing, and patient race. Preventive visits appear to have the most effect; additional research should include examining clinical notes for evidence of nutrition care among different populations, which may uncover areas for improving nutrition care for patients with chronic disease.


Asunto(s)
Registros Electrónicos de Salud , Hipertensión , Adulto , Humanos , Masculino , Persona de Mediana Edad , Femenino , Presión Sanguínea , Sobrepeso/epidemiología , Hipertensión/complicaciones , Obesidad/epidemiología
8.
Nature ; 529(7584): 92-6, 2016 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-26675724

RESUMEN

Insulin/insulin-like growth factor signalling (IIS) is a critical regulator of an organism's most important biological decisions from growth, development, and metabolism to reproduction and longevity. It primarily does so through the activity of the DAF-16 transcription factor (forkhead box O (FOXO) homologue), whose global targets were identified in Caenorhabditis elegans using whole-worm transcriptional analyses more than a decade ago. IIS and FOXO also regulate important neuronal and adult behavioural phenotypes, such as the maintenance of memory and axon regeneration with age, in both mammals and C. elegans, but the neuron-specific IIS/FOXO targets that regulate these functions are still unknown. By isolating adult C. elegans neurons for transcriptional profiling, we identified both the wild-type and IIS/FOXO mutant adult neuronal transcriptomes for the first time. IIS/FOXO neuron-specific targets are distinct from canonical IIS/FOXO-regulated longevity and metabolism targets, and are required for extended memory in IIS daf-2 mutants. The activity of the forkhead transcription factor FKH-9 in neurons is required for the ability of daf-2 mutants to regenerate axons with age, and its activity in non-neuronal tissues is required for the long lifespan of daf-2 mutants. Together, neuron-specific and canonical IIS/FOXO-regulated targets enable the coordinated extension of neuronal activities, metabolism, and longevity under low-insulin signalling conditions.


Asunto(s)
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Factores de Transcripción Forkhead/metabolismo , Insulina/metabolismo , Neuronas/metabolismo , Fenotipo , Transducción de Señal , Somatomedinas/metabolismo , Transcriptoma , Envejecimiento/genética , Animales , Axones/fisiología , Caenorhabditis elegans/citología , Caenorhabditis elegans/fisiología , Proteínas de Caenorhabditis elegans/genética , Separación Celular , Factores de Transcripción Forkhead/genética , Longevidad/genética , Mecanotransducción Celular , Memoria/fisiología , Mutación/genética , Neuronas/citología , Regeneración/genética
9.
Fam Pract ; 39(5): 860-867, 2022 09 24.
Artículo en Inglés | MEDLINE | ID: mdl-35325099

RESUMEN

BACKGROUND: Screening for food insecurity (FI) and providing nutrition care are important management strategies for chronic diseases, but rates are low. Aspects of team-based care and providers' nutrition competence may help inform interventions to improve these services. The objectives of this study were to describe US primary care providers' FI screening and nutrition care practices (counselling, referrals, and time spent counselling) and test for associations with scored measures of their perceptions of team-based care (care continuity, patient-centredness, coordination with external providers and resources) and nutrition competence (confidence counselling and attitudes towards nutrition). METHODS: Cross-sectional online survey data of primary care providers were described and analysed for associations using Wilcoxon rank sum tests. RESULTS: Of provider respondents (N = 92), 35% (n = 32) worked in clinics that screen for FI and had higher team perceptions (P = 0.006) versus those who do not. Those who reported counselling >30% patients about nutrition (57%, n = 52) and referring >10% patients to nutrition professionals (24%, n = 22) had significantly better attitudes towards nutrition (P = 0.013 and P = 0.04, respectively) compared with those with lower counselling and referral rates. Half (n = 46) of the providers reported spending >3-min counselling each patient about nutrition and had higher patient-centred care (P = 0.004) and nutrition competence (P < 0.001) compared with those who spent less time counselling. CONCLUSION: Providers in clinics that screen for FI had higher overall perceptions of team-based care, but their nutrition competence was not significantly different. Meanwhile, reported more time counselling was associated with a culture of patient-centredness. Promoting team-based care may be a mechanism for improving FI screening and nutrition care.


Asunto(s)
Tamizaje Masivo , Derivación y Consulta , Estudios Transversales , Inseguridad Alimentaria , Humanos , Atención Primaria de Salud
10.
Prev Med ; 145: 106426, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33450214

RESUMEN

Clinicians supporting patients in lifestyle behavior change is an important strategy to help reduce chronic disease burden. Using National Health and Nutrition Examination Survey (NHANES) data from 2015 to 2018, this study assessed rates of and associations between patient-reported receipt of lifestyle behavior change advice and corresponding self-reported behavior change for four different lifestyle behaviors: 1) weight loss, 2) increase physical activity, 3) reduce sodium, and 4) reduce fat and calories. Adult survey respondents with hypertension and/or diabetes (n = 4716) who received lifestyle advice ranged from 43% to 58%, with the most common recommendation being to increase physical activity. Between 61% and 73% of respondents reported currently modifying health behaviors, with the greatest number reporting weight loss. Multiple logistic regression models were used to test associations for each lifestyle behavior advice-behavior change pair, adjusting for demographic characteristics. Compared to those who received no advice, respondents who received advice had significantly higher odds of reporting losing weight (aOR: 1.93; 95% CI: 1.51, 2.48); increasing physical activity (aOR 2.02; 95% CI: 1.73, 2.37); reducing dietary sodium (aOR 4.95; 95% CI: 3.93, 6.25); and reducing intake of fat/cal (aOR 3.57; 95% CI: 2.86, 4.45). This study utilized population level data to lend further evidence that provider advice about lifestyle behaviors for patients who have hypertension or diabetes may influence patient behavior. However, prevalence of advice is low, and differences in rates of behavior change exist across socioeconomic status and race/ethnicity, indicating a need to further research how providers might better support patients with varying social needs.


Asunto(s)
Diabetes Mellitus , Hipertensión , Adulto , Estudios Transversales , Conductas Relacionadas con la Salud , Humanos , Estilo de Vida , Encuestas Nutricionales
11.
PLoS Genet ; 14(8): e1007559, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30096138

RESUMEN

The biology and behavior of adults differ substantially from those of developing animals, and cell-specific information is critical for deciphering the biology of multicellular animals. Thus, adult tissue-specific transcriptomic data are critical for understanding molecular mechanisms that control their phenotypes. We used adult cell-specific isolation to identify the transcriptomes of C. elegans' four major tissues (or "tissue-ome"), identifying ubiquitously expressed and tissue-specific "enriched" genes. These data newly reveal the hypodermis' metabolic character, suggest potential worm-human tissue orthologies, and identify tissue-specific changes in the Insulin/IGF-1 signaling pathway. Tissue-specific alternative splicing analysis identified a large set of collagen isoforms. Finally, we developed a machine learning-based prediction tool for 76 sub-tissue cell types, which we used to predict cellular expression differences in IIS/FOXO signaling, stage-specific TGF-ß activity, and basal vs. memory-induced CREB transcription. Together, these data provide a rich resource for understanding the biology governing multicellular adult animals.


Asunto(s)
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Perfilación de la Expresión Génica , Empalme Alternativo , Animales , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo , Regulación de la Expresión Génica , Biblioteca de Genes , Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Modelos Moleculares , Fenotipo , Isoformas de Proteínas , Análisis de Secuencia de ARN , Transducción de Señal , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo
12.
Nature ; 507(7491): 253-257, 2014 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-24572359

RESUMEN

Commitment to and completion of sexual development are essential for malaria parasites (protists of the genus Plasmodium) to be transmitted through mosquitoes. The molecular mechanism(s) responsible for commitment have been hitherto unknown. Here we show that PbAP2-G, a conserved member of the apicomplexan AP2 (ApiAP2) family of DNA-binding proteins, is essential for the commitment of asexually replicating forms to sexual development in Plasmodium berghei, a malaria parasite of rodents. PbAP2-G was identified from mutations in its encoding gene, PBANKA_143750, which account for the loss of sexual development frequently observed in parasites transmitted artificially by blood passage. Systematic gene deletion of conserved ApiAP2 genes in Plasmodium confirmed the role of PbAP2-G and revealed a second ApiAP2 member (PBANKA_103430, here termed PbAP2-G2) that significantly modulates but does not abolish gametocytogenesis, indicating that a cascade of ApiAP2 proteins are involved in commitment to the production and maturation of gametocytes. The data suggest a mechanism of commitment to gametocytogenesis in Plasmodium consistent with a positive feedback loop involving PbAP2-G that could be exploited to prevent the transmission of this pernicious parasite.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Células Germinativas/crecimiento & desarrollo , Malaria/parasitología , Plasmodium berghei/genética , Plasmodium berghei/fisiología , Proteínas Protozoarias/metabolismo , Desarrollo Sexual/genética , Animales , Culicidae/parasitología , Proteínas de Unión al ADN/deficiencia , Proteínas de Unión al ADN/genética , Retroalimentación Fisiológica , Femenino , Regulación de la Expresión Génica , Células Germinativas/citología , Células Germinativas/metabolismo , Masculino , Mutación/genética , Plasmodium berghei/citología , Transporte de Proteínas , Proteínas Protozoarias/genética , Reproducción Asexuada , Transcripción Genética
13.
Nature ; 507(7491): 248-52, 2014 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-24572369

RESUMEN

The life cycles of many parasites involve transitions between disparate host species, requiring these parasites to go through multiple developmental stages adapted to each of these specialized niches. Transmission of malaria parasites (Plasmodium spp.) from humans to the mosquito vector requires differentiation from asexual stages replicating within red blood cells into non-dividing male and female gametocytes. Although gametocytes were first described in 1880, our understanding of the molecular mechanisms involved in commitment to gametocyte formation is extremely limited, and disrupting this critical developmental transition remains a long-standing goal. Here we show that expression levels of the DNA-binding protein PfAP2-G correlate strongly with levels of gametocyte formation. Using independent forward and reverse genetics approaches, we demonstrate that PfAP2-G function is essential for parasite sexual differentiation. By combining genome-wide PfAP2-G cognate motif occurrence with global transcriptional changes resulting from PfAP2-G ablation, we identify early gametocyte genes as probable targets of PfAP2-G and show that their regulation by PfAP2-G is critical for their wild-type level expression. In the asexual blood-stage parasites pfap2-g appears to be among a set of epigenetically silenced loci prone to spontaneous activation. Stochastic activation presents a simple mechanism for a low baseline of gametocyte production. Overall, these findings identify PfAP2-G as a master regulator of sexual-stage development in malaria parasites and mark the first discovery of a transcriptional switch controlling a differentiation decision in protozoan parasites.


Asunto(s)
Regulación de la Expresión Génica/genética , Células Germinativas/crecimiento & desarrollo , Malaria/parasitología , Parásitos/fisiología , Plasmodium falciparum/genética , Desarrollo Sexual/genética , Transcripción Genética/genética , Animales , Proteínas de Unión al ADN/deficiencia , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Femenino , Silenciador del Gen , Genes Protozoarios/genética , Genoma de Protozoos/genética , Células Germinativas/citología , Células Germinativas/metabolismo , Masculino , Parásitos/citología , Parásitos/genética , Plasmodium falciparum/citología , Plasmodium falciparum/fisiología , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Reproducción Asexuada , Diferenciación Sexual/genética
14.
RNA ; 23(8): 1200-1208, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28450531

RESUMEN

The ciliate Oxytricha trifallax maintains two genomes: a germline genome that is active only during sexual conjugation and a transcriptionally active, somatic genome that derives from the germline via extensive sequence reduction and rearrangement. Previously, we found that long noncoding (lnc) RNA "templates"-telomere-containing, RNA-cached copies of mature chromosomes-provide the information to program the rearrangement process. Here we used a modified RNA-seq approach to conduct the first genome-wide search for endogenous, telomere-to-telomere RNA transcripts. We find that during development, Oxytricha produces long noncoding RNA copies for over 10,000 of its 16,000 somatic chromosomes, consistent with a model in which Oxytricha transmits an RNA-cached copy of its somatic genome to the sexual progeny. Both the primary sequence and expression profile of a somatic chromosome influence the temporal distribution and abundance of individual template RNAs. This suggests that Oxytricha may undergo multiple rounds of DNA rearrangement during development. These observations implicate a complex set of thousands of long RNA molecules in the wiring and maintenance of a highly elaborate somatic genome architecture.


Asunto(s)
Cromosomas/genética , Genoma de Protozoos/genética , Oxytricha/genética , ARN Largo no Codificante/genética , ARN Protozoario/genética , Animales , Variaciones en el Número de Copia de ADN , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Oxytricha/crecimiento & desarrollo , Telómero/genética
15.
Gastrointest Endosc ; 87(1): 205-210, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28455162

RESUMEN

BACKGROUND AND AIMS: The EPISOD (Evaluating Predictors and Interventions in Sphincter of Oddi Dysfunction) study randomized patients with post-cholecystectomy pain, and little or no objective evidence for biliary obstruction, to sphincterotomy or sham intervention. Results at 1 year showed no benefit for the active treatment. We now report the outcomes at up to 5 years. METHODS: One hundred three patients completing 1 year, and still blinded to treatment allocation, were enrolled and followed by phone every 6 months for a median of 58 months (range, 17-71 months). Their success was assessed at the final visit by 2 criteria: (1) a low pain score (Recurrent Abdominal Pain and Disability instrument [RAPID] <6) and (2) much or very much improved on the Patients' Global Impression of Change (PGIC) questionnaire (both with no repeat intervention and not taking narcotics). RESULTS: By the RAPID criteria, success rates for the patients in the sphincterotomy and sham arms were similar: 26/65 (40%) versus 16/38 (42%), respectively. However, by the PGIC criteria, actively treated patients fared worse: 16/43 (37%) versus 16/22 (73%). A total of 75 patients underwent active treatment during the entire study. Their success rate by the RAPID criteria was 31 (41%) compared with 16 (62%) who had no active treatment at any time. CONCLUSIONS: These data confirm our initial report that endoscopic sphincterotomy is no better than sham intervention in these patients (and, by some criteria, worse), and that ERCP can no longer be recommended. The patients have genuine and often severe symptoms, and further research is needed to establish effective management. (Clinical trial registration number: 00688662 05/3/2008.).


Asunto(s)
Dolor Abdominal/cirugía , Colangiopancreatografia Retrógrada Endoscópica/métodos , Colecistectomía , Dolor Postoperatorio/cirugía , Disfunción del Esfínter de la Ampolla Hepatopancreática/cirugía , Esfínter de la Ampolla Hepatopancreática/cirugía , Esfinterotomía Endoscópica/métodos , Adulto , Humanos
16.
Nat Methods ; 9(10): 993-8, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22922501

RESUMEN

Malaria afflicts over 200 million people worldwide, and its most lethal etiologic agent, Plasmodium falciparum, is evolving to resist even the latest-generation therapeutics. Efficient tools for genome-directed investigations of P. falciparum-induced pathogenesis, including drug-resistance mechanisms, are clearly required. Here we report rapid and targeted genetic engineering of this parasite using zinc-finger nucleases (ZFNs) that produce a double-strand break in a user-defined locus and trigger homology-directed repair. Targeting an integrated egfp locus, we obtained gene-deletion parasites with unprecedented speed (2 weeks), both with and without direct selection. ZFNs engineered against the parasite gene pfcrt, responsible for escape under chloroquine treatment, rapidly produced parasites that carried either an allelic replacement or a panel of specified point mutations. This method will enable a diverse array of genome-editing approaches to interrogate this human pathogen.


Asunto(s)
Endonucleasas/fisiología , Genoma de Protozoos , Plasmodium falciparum/genética , Ingeniería de Proteínas/métodos , Dedos de Zinc/fisiología , Alelos , Secuencia de Bases , Cloroquina/farmacología , Resistencia a Medicamentos/genética , Endonucleasas/genética , Datos de Secuencia Molecular , Plasmodium falciparum/efectos de los fármacos , Dedos de Zinc/genética
17.
Endoscopy ; 47(10): 884-90, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26165739

RESUMEN

BACKGROUND AND STUDY AIM: Pancreatitis following endoscopic retrograde cholangiopancreatography (ERCP) is a significant and potentially life-threatening adverse event and is common in patients with suspected sphincter of Oddi dysfunction (SOD). Here we aimed to identify predictors of the risk in this population. PATIENTS AND METHODS: The Evaluating Predictors and Interventions in SOD (EPISOD) study prospectively enrolled 214 post-cholecystectomy patients with SOD type III in seven US centers. Patients were randomized, using a 2:1 allocation, to sphincterotomy or sham procedure, irrespective of the results of sphincter of Oddi manometry. Patients in the sphincterotomy arm who had elevated pancreatic sphincter pressure were randomized to biliary only or to dual (biliary and pancreatic) sphincterotomy. All but one patient received prophylactic pancreatic stents, but none received pharmacological prophylaxis. Post ERCP pancreatitis (PEP) was defined as acute pancreatitis within the subsequent 7 days. Blinded research coordinators at each site called patients at 1 week post-procedure. RESULTS: PEP occurred in 26 patients, in 10.6 % (15/141) in the sphincterotomy arm and 15.1 % (11/73) in the sham arm; unadjusted relative risk 0.71 (95 % confidence interval [95 %CI] 0.34 - 1.46). PEP rate was not significantly different in patients who received sphincterotomy compared with those undergoing sham treatment. In addition, the proportion was not statistically different in those who received biliary sphincterotomy alone (12/94; 12.8 % [95 %CI 6.0 % - 19.5 %]) compared with dual sphincterotomy (3/47; 6.4 % [95 %CI 0.0 % - 13.4 %]). Multivariate analysis identified an interaction between duration of ERCP and sedation type (P < 0.02). CONCLUSION: The performance of biliary or dual sphincterotomy does not increase the risk of PEP in patients suspected of SOD. However, the high rate of PEP in patients with suspected SOD, despite pancreatic stenting in expert centers, is confirmed in this prospective study. The combined effect of duration of ERCP and sedation type on the development of PEP should be further explored.Clinicaltrials.gov registration: NCT00688662.


Asunto(s)
Colangiopancreatografia Retrógrada Endoscópica/efectos adversos , Enfermedades del Conducto Colédoco/cirugía , Pancreatitis/epidemiología , Complicaciones Posoperatorias/epidemiología , Disfunción del Esfínter de la Ampolla Hepatopancreática/cirugía , Esfínter de la Ampolla Hepatopancreática/fisiopatología , Esfinterotomía Endoscópica/efectos adversos , Adulto , Enfermedades del Conducto Colédoco/fisiopatología , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Manometría , Persona de Mediana Edad , Pancreatitis/diagnóstico , Pancreatitis/etiología , Complicaciones Posoperatorias/diagnóstico , Presión , Pronóstico , Estudios Prospectivos , Esfínter de la Ampolla Hepatopancreática/cirugía , Disfunción del Esfínter de la Ampolla Hepatopancreática/diagnóstico , Disfunción del Esfínter de la Ampolla Hepatopancreática/fisiopatología , Stents , Estados Unidos/epidemiología , Adulto Joven
18.
Gastrointest Endosc ; 79(5): 765-72, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24472759

RESUMEN

BACKGROUND: Biliopancreatic-type postcholecystectomy pain, without significant abnormalities on imaging and laboratory test results, has been categorized as "suspected" sphincter of Oddi dysfunction (SOD) type III. Clinical predictors of "manometric" SOD are important to avoid unnecessary ERCP, but are unknown. OBJECTIVE: To assess which clinical factors are associated with abnormal sphincter of Oddi manometry (SOM). DESIGN: Prospective, cross-sectional. SETTING: Tertiary. PATIENTS: A total of 214 patients with suspected SOD type III underwent ERCP and pancreatic SOM (pSOM; 85% dual SOM), at 7 U.S. centers (from August 2008 to March 2012) as part of a randomized trial. INTERVENTIONS: Pain and gallbladder descriptors, psychosocial/functional disorder questionnaires. MAIN OUTCOME MEASUREMENTS: Abnormal SOM findings. Univariate and multivariate analyses assessed associations between clinical characteristics and outcome. RESULTS: The cohort was 92% female with a mean age of 38 years. Baseline pancreatic enzymes were increased in 5%; 9% had minor liver enzyme abnormalities. Pain was in the right upper quadrant (RUQ) in 90% (48% also epigastric); 51% reported daily abdominal discomfort. Fifty-six took narcotics an average of 33 days (of the past 90 days). Less than 10% experienced depression or anxiety. Functional disorders were common. At ERCP, 64% had abnormal pSOM findings (34% both sphincters, 21% biliary normal), 36% had normal pSOM findings, and 75% had at least abnormal 1 sphincter. Demographic factors, gallbladder pathology, increased pancreatobiliary enzymes, functional disorders, and pain patterns did not predict abnormal SOM findings. Anxiety, depression, and poorer coping were more common in patients with normal SOM findings (not significant on multivariate analysis). LIMITATIONS: Generalizability. CONCLUSIONS: Patient and pain factors and psychological comorbidity do not predict SOM results at ERCP in suspected type III SOD. ( CLINICAL TRIAL REGISTRATION NUMBER: NCT00688662.).


Asunto(s)
Dolor Abdominal/etiología , Disfunción del Esfínter de la Ampolla Hepatopancreática/diagnóstico , Disfunción del Esfínter de la Ampolla Hepatopancreática/fisiopatología , Adulto , Analgésicos Opioides/uso terapéutico , Ansiedad/psicología , Colangiopancreatografia Retrógrada Endoscópica , Colecistectomía , Estudios Transversales , Depresión/psicología , Femenino , Humanos , Masculino , Manometría , Persona de Mediana Edad , Periodo Posoperatorio , Valor Predictivo de las Pruebas , Estudios Prospectivos , Escalas de Valoración Psiquiátrica , Disfunción del Esfínter de la Ampolla Hepatopancreática/psicología
19.
JAMA ; 311(20): 2101-9, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24867013

RESUMEN

IMPORTANCE: Abdominal pain after cholecystectomy is common and may be attributed to sphincter of Oddi dysfunction. Management often involves endoscopic retrograde cholangiopancreatography (ERCP) with manometry and sphincterotomy. OBJECTIVE: To determine whether endoscopic sphincterotomy reduces pain and whether sphincter manometric pressure is predictive of pain relief. DESIGN, SETTING, AND PATIENTS: Multicenter, sham-controlled, randomized trial involving 214 patients with pain after cholecystectomy without significant abnormalities on imaging or laboratory studies, and no prior sphincter treatment or pancreatitis randomly assigned (August 6, 2008-March 23, 2012) to undergo sphincterotomy or sham therapy at 7 referral medical centers. One-year follow-up was blinded. The final follow-up visit was March 21, 2013. INTERVENTIONS: After ERCP, patients were randomized 2:1 to sphincterotomy (n = 141) or sham (n = 73) irrespective of manometry findings. Those randomized to sphincterotomy with elevated pancreatic sphincter pressures were randomized again (1:1) to biliary or to both biliary and pancreatic sphincterotomies. Seventy-two were entered into an observational study with conventional ERCP managemeny. MAIN OUTCOMES AND MEASURES: Success of treatment was defined as less than 6 days of disability due to pain in the prior 90 days both at months 9 and 12 after randomization, with no narcotic use and no further sphincter intervention. RESULTS: Twenty-seven patients (37%; 95% CI, 25.9%-48.1%) in the sham treatment group vs 32 (23%; 95% CI, 15.8%-29.6%) in the sphincterotomy group experienced successful treatment (adjusted risk difference, -15.6%; 95% CI, -28.0% to -3.3%; P = .01). Of the patients with pancreatic sphincter hypertension, 14 (30%; 95% CI, 16.7%-42.9%) who underwent dual sphincterotomy and 10 (20%; 95% CI, 8.7%-30.5%) who underwent biliary sphincterotomy alone experienced successful treatment. Thirty-seven treated patients (26%; 95% CI,19%-34%) and 25 patients (34%; 95% CI, 23%-45%) in the sham group underwent repeat ERCP interventions (P = .22). Manometry results were not associated with the outcome. No clinical subgroups appeared to benefit from sphincterotomy more than others. Pancreatitis occurred in 15 patients (11%) after primary sphincterotomies and in 11 patients (15%) in the sham group. Of the nonrandomized patients in the observational study group, 5 (24%; 95% CI, 6%-42%) who underwent biliary sphincterotomy, 12 (31%; 95% CI, 16%-45%) who underwent dual sphincterotomy, and 2 (17%; 95% CI, 0%-38%) who did not undergo sphincterotomy had successful treatment. CONCLUSIONS AND RELEVANCE: In patients with abdominal pain after cholecystectomy undergoing ERCP with manometry, sphincterotomy vs sham did not reduce disability due to pain. These findings do not support ERCP and sphincterotomy for these patients. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00688662.


Asunto(s)
Dolor Abdominal/fisiopatología , Colecistectomía/efectos adversos , Disfunción del Esfínter de la Ampolla Hepatopancreática/etiología , Disfunción del Esfínter de la Ampolla Hepatopancreática/cirugía , Esfinterotomía Endoscópica/métodos , Dolor Abdominal/etiología , Adulto , Colangiopancreatografia Retrógrada Endoscópica/métodos , Femenino , Estado de Salud , Humanos , Masculino , Manometría , Persona de Mediana Edad , Narcóticos/uso terapéutico , Pancreatitis , Esfinterotomía Endoscópica/efectos adversos , Resultado del Tratamiento , Adulto Joven
20.
bioRxiv ; 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38854090

RESUMEN

Motivation: Whole-genome bisulfite sequencing is a powerful tool for analyzing chromatin methylation genome-wide, but analysis of whole-genome bisulfite data is hampered by slow, inaccurate, and inflexible pipelines. Results: We developed PCBS, a computationally efficient R package for Whole Genome Bisulfite Sequencing analysis that demonstrates remarkable accuracy and flexibility compared to current tools. PCBS identifies differentially methylated loci and differentially methylated regions and offers novel functionality that allows for more targeted methylation analyses. PCBS uses minimal computational resources; a complete pipeline in mouse can run on a local RStudio instance in a matter of minutes. Availability and Implementation: PCBS is an R package available under a GNU GPLv3 license at: https://github.com/katlande/PCBS and from CRAN: https://CRAN.R-project.org/package=PCBS. Instructions for use are available at: https://katlande.github.io/PCBS/.

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