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1.
Contemp Clin Trials ; 133: 107323, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37661005

RESUMEN

BACKGROUND: Genetic counseling and testing have an important role in the care of patients at elevated risk for breast cancer. However, conventional pre- and post-test genetic counseling is labor and time intensive, less accessible for patients living outside major urban centers, and impractical on a large scale. A patient-driven approach to genetic counseling and testing may increase access, improve patients' experiences, affect efficiency of clinical practice, and help meet workforce demand. The objective of this 2-arm randomized controlled trial is to determine the efficacy of Know Your Risk (KYR), a genetic counseling patient preference intervention. METHODS: Females (n = 1000) at elevated risk (>20% lifetime) for breast cancer will be randomized to the KYR intervention or conventional genetic counseling. The study will provide comprehensive assessment of breast cancer risk by multigene panel testing and validated polygenic risk score. Primary outcome is adherence to National Comprehensive Cancer Network guidelines for a clinical encounter every 6-12 months and an annual mammogram (breast MRI if recommended) determined by medical record review. Secondary outcomes include adherence to other recommended cancer screening tests determined by medical record review and changes in breast cancer knowledge, perception of risk, post-test/counseling distress, and satisfaction with counseling by completion of three surveys during the study. Study aims will be evaluated for non-inferiority of the KYR intervention compared to conventional genetic counseling. CONCLUSION: If efficacious, the KYR intervention has the potential to improve patients' experience and may change how genetic counseling is delivered, inform best practices, and reduce workforce burden. TRIAL REGISTRATION: ClinicalTrials.govNCT05325151.


Asunto(s)
Neoplasias de la Mama , Asesoramiento Genético , Humanos , Femenino , Asesoramiento Genético/métodos , Asesoramiento Genético/psicología , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Neoplasias de la Mama/psicología , Consejo , Factores de Riesgo , Pruebas Genéticas/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto
2.
Gynecol Oncol ; 172: 106-114, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37004303

RESUMEN

OBJECTIVE: A quality improvement initiative (QII) was conducted with five community-based health systems' oncology care centers (sites A-E). The QII aimed to increase referrals, genetic counseling (GC), and germline genetic testing (GT) for patients with ovarian cancer (OC) and triple-negative breast cancer (TNBC). METHODS: QII activities occurred at sites over several years, all concluding by December 2020. Medical records of patients with OC and TNBC were reviewed, and rates of referral, GC, and GT of patients diagnosed during the 2 years before the QII were compared to those diagnosed during the QII. Outcomes were analyzed using descriptive statistics, two-sample t-test, chi-squared/Fisher's exact test, and logistic regression. RESULTS: For patients with OC, improvement was observed in the rate of referral (from 70% to 79%), GC (from 44% to 61%), GT (from 54% to 62%) and decreased time from diagnosis to GC and GT. For patients with TNBC, increased rates of referral (from 90% to 92%), GC (from 68% to 72%) and GT (81% to 86%) were observed. Effective interventions streamlined GC scheduling and standardized referral processes. CONCLUSION: A multi-year QII increased patient referral and uptake of recommended genetics services across five unique community-based oncology care settings.


Asunto(s)
Neoplasias Ováricas , Neoplasias de la Mama Triple Negativas , Femenino , Humanos , Mejoramiento de la Calidad , Neoplasias de la Mama Triple Negativas/genética , Pruebas Genéticas , Neoplasias Ováricas/genética , Neoplasias Ováricas/terapia , Asesoramiento Genético
3.
FP Essent ; 511: 29-35, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34855339

RESUMEN

Nonalcoholic fatty liver disease (NAFLD) describes a spectrum of fatty infiltration, inflammation, and fibrosis of the liver caused by metabolic factors. It is projected to become the leading cause of cirrhosis and need for liver transplantation in the United States. Guidelines from the American Association for the Study of Liver Diseases (AASLD) do not recommend routine screening of patients at high risk of NAFLD. European guidelines recommend testing for certain high-risk patients. Hepatic steatosis and nonalcoholic steatohepatitis (NASH) are difficult to diagnose and often go unrecognized until patients have advanced fibrosis or cirrhosis. Noninvasive methods are used to assess fibrosis, such as fibrosis scores and vibration-controlled transient elastography. Liver biopsy remains the reference standard for NASH diagnosis and fibrosis staging. The mainstays of treatment for NAFLD, NASH, and fibrosis are weight loss and a healthy diet. Currently, no drugs have been approved by the Food and Drug Administration (FDA) for management of these conditions. Drugs for diabetes management (eg, glucagon-like peptide 1 receptor agonists, pioglitazone) can be useful in patients with diabetes and NASH. Among patients with NAFLD, cardiovascular disease is a common cause of mortality. Thus, the AASLD guidelines recommend consideration of omega-3 fatty acids for hypertriglyceridemia management in patients with NAFLD, and statins for hyperlipidemia management in most patients with NAFLD and NASH.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Humanos , Hígado/patología , Cirrosis Hepática , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Enfermedad del Hígado Graso no Alcohólico/terapia
4.
FP Essent ; 511: 23-28, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34855338

RESUMEN

Approximately 4.1 million individuals in the United States have a history of hepatitis C virus (HCV) exposure, including 2.5 million with chronic infection. Screening guidelines recommend one-time, routine, opt out HCV screening for all individuals 18 years or older. Risk-based testing is recommended for specific individuals. Although many patients with chronic hepatitis C may progress to cirrhosis, end-stage liver disease, and hepatocellular carcinoma, early treatment can prevent development of these sequelae. Management of hepatitis C has simplified significantly, and primary care physicians now can monitor and provide treatment for most patients. Adults with chronic hepatitis C who do not have cirrhosis and have not received hepatitis C treatment previously are eligible for primary care-based treatment. These patients should undergo a comprehensive pretreatment evaluation to guide treatment planning. Patients typically are treated with one of two pangenotypic regimens: glecaprevir-pibrentasvir for 8 weeks or sofosbuvir-velpatasvir for 12 weeks. Virologic cure, defined as sustained virologic response (SVR) at 12 weeks after treatment completion, should be confirmed by an undetectable quantitative HCV RNA via polymerase chain reaction test performed 12 weeks or later after treatment completion. Management results in rates of virologic cure of greater than 95% across genotypes. Patients who do not achieve SVR at 12 weeks should be referred to a subspecialist experienced in management of treatment failure.


Asunto(s)
Hepatitis C Crónica , Hepatitis C , Antivirales/uso terapéutico , Combinación de Medicamentos , Hepacivirus/genética , Hepatitis C/tratamiento farmacológico , Hepatitis C Crónica/diagnóstico , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Cirrosis Hepática/diagnóstico , Infección Persistente , Resultado del Tratamiento
5.
FP Essent ; 511: 36-43, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34855340

RESUMEN

Cirrhosis is pathologic scarring of liver tissue that leads to impaired liver function. It can result from any etiology of chronic liver inflammation and causes significant disease burden. Cirrhosis potentially is reversible through management of the cause, such as nonalcoholic fatty liver disease, viral hepatitis, or alcohol use. As liver disease progresses, compensated (ie, asymptomatic) cirrhosis may decompensate, causing ascites, hepatic encephalopathy, or variceal bleeding. Cirrhosis typically is diagnosed with a history, physical examination, and noninvasive testing, which includes laboratory tests, combination scoring indices, and imaging (eg, ultrasonography, transient elastography). Liver biopsy remains the reference standard for diagnosis. It should be used when results of noninvasive evaluation are indeterminate, when the etiology of liver disease remains unknown, or when the result may alter management. Clinicians should counsel patients about alcohol use, obesity management, and prevention of infection. Drugs with potential for hepatotoxicity should be avoided. Clinical assessment with laboratory tests and calculation of the Child-Pugh and Model for End-stage Liver Disease (MELD) scores should occur every 6 months. Clinicians should evaluate for and manage cirrhosis-related complications, including hepatocellular carcinoma, ascites, spontaneous bacterial peritonitis, hepatic encephalopathy, esophageal varices, and other complications. Evaluation for liver transplantation is indicated for patients with a MELD score of 15 or greater, complications of cirrhosis, or hepatocellular carcinoma.


Asunto(s)
Enfermedad Hepática en Estado Terminal , Várices Esofágicas y Gástricas , Várices Esofágicas y Gástricas/diagnóstico , Várices Esofágicas y Gástricas/etiología , Várices Esofágicas y Gástricas/terapia , Hemorragia Gastrointestinal , Humanos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/terapia , Índice de Severidad de la Enfermedad
6.
Nature ; 591(7851): 671-676, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33658710

RESUMEN

Meiotic processes are potentially dangerous to genome stability and could be disastrous if activated in proliferative cells. Here we show that two key meiosis-defining proteins, the topoisomerase Spo11 (which forms double-strand breaks) and the meiotic cohesin Rec8, can dismantle centromeres. This dismantlement is normally observable only in mutant cells that lack the telomere bouquet, which provides a nuclear microdomain conducive to centromere reassembly1; however, overexpression of Spo11 or Rec8 leads to levels of centromere dismantlement that cannot be countered by the bouquet. Specific nucleosome remodelling factors mediate centromere dismantlement by Spo11 and Rec8. Ectopic expression of either protein in proliferating cells leads to the loss of mitotic kinetochores in both fission yeast and human cells. Hence, while centromeric chromatin has been characterized as extraordinarily stable, Spo11 and Rec8 challenge this stability and may jeopardize kinetochores in cancers that express meiotic proteins.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Centrómero/química , Centrómero/metabolismo , Endodesoxirribonucleasas/metabolismo , Meiosis , Fosfoproteínas/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Línea Celular , Proliferación Celular , Cromatina/química , Cromatina/metabolismo , Humanos , Cinetocoros/metabolismo , Schizosaccharomyces
8.
J Genet Couns ; 2018 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-29770910

RESUMEN

An environmental scan (ES) is an efficient mixed-methods approach to collect and interpret relevant data for strategic planning and project design. To date, the ES has not been used nor evaluated in the clinical cancer genetics setting. We created and implemented an ES to inform the design of a quality improvement (QI) project to increase the rates of adherence to national guidelines for cancer genetic counseling and genetic testing at three unique oncology care settings (OCS). The ES collected qualitative and quantitative data from reviews of internal processes, past QI efforts, the literature, and each OCS. The ES used a data collection form and semi-structured interviews to aid in data collection. The ES was completed within 6 months, and sufficient data were captured to identify opportunities and threats to the QI project's success, as well as potential barriers to, and facilitators of guideline-based cancer genetics services at each OCS. Previously unreported barriers were identified, including inefficient genetic counseling appointment scheduling processes and the inability to track referrals, genetics appointments, and genetic test results within electronic medical record systems. The ES was a valuable process for QI project planning at three OCS and may be used to evaluate genetics services in other settings.

9.
Genes Dev ; 32(7-8): 537-554, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-29654060

RESUMEN

The identification of telomerase-negative HAATI (heterochromatin amplification-mediated and telomerase-independent) cells, in which telomeres are superseded by nontelomeric heterochromatin tracts, challenged the idea that canonical telomeres are essential for chromosome linearity and raised crucial questions as to how such tracts translocate to eroding chromosome ends and confer end protection. Here we show that HAATI arises when telomere loss triggers a newly recognized illegitimate translocation pathway that requires RNAi factors. While RNAi is necessary for the translocation events that mobilize ribosomal DNA (rDNA) tracts to all chromosome ends (forming "HAATIrDNA" chromosomes), it is dispensable for HAATIrDNA maintenance. Surprisingly, Dicer (Dcr1) plays a separate, RNAi-independent role in preventing formation of the rare HAATI subtype in which a different repetitive element (the subtelomeric element) replaces telomeres. Using genetics and fusions between shelterin components and rDNA-binding proteins, we mapped the mechanism by which rDNA loci engage crucial end protection factors-despite the absence of telomere repeats-and secure end protection. Sequence analysis of HAATIrDNA genomes allowed us to propose RNA and DNA polymerase template-switching models for the mechanism of RNAi-triggered rDNA translocations. Collectively, our results reveal unforeseen roles for noncoding RNAs (ncRNAs) in assembling a telomere-free chromosome end protection device.


Asunto(s)
ADN Ribosómico , Heterocromatina , Interferencia de ARN , Translocación Genética , Reparación del ADN , Proteínas de Unión al ADN/fisiología , Recombinasa Rad51/fisiología , Ribonucleasa III/metabolismo , Ribonucleasa III/fisiología , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Proteínas de Schizosaccharomyces pombe/fisiología , Complejo Shelterina , Telómero , Proteínas de Unión a Telómeros/metabolismo , Secuencias Repetidas Terminales
10.
Crit Rev Biochem Mol Biol ; 52(1): 57-73, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27892716

RESUMEN

While most cancer cells rely on telomerase expression/re-activation for linear chromosome maintenance and sustained proliferation, a significant population of cancers (10-15%) employs telomerase-independent strategies, collectively dubbed Alternative Lengthening of Telomeres (ALT). Most ALT cells relax the usual role of telomeres as inhibitors of local homologous recombination while maintaining the ability of telomeres to prohibit local non-homologous end joining reactions. Here we review current concepts surrounding how ALT telomeres achieve this new balance via alterations in chromatin landscape, DNA damage repair processes and handling of telomeric transcription. We also discuss telomerase independent end maintenance strategies utilized by other organisms, including fruitflies and yeasts, to draw parallels and contrasts and highlight additional modes, beyond ALT, that may be available to telomerase-minus cancers. We conclude by commenting on promises and challenges in the development of effective anti-ALT cancer therapies.


Asunto(s)
Reparación del ADN , Telomerasa/metabolismo , Homeostasis del Telómero , Telómero/metabolismo , Animales , Cromatina/genética , Cromatina/metabolismo , Daño del ADN , Evolución Molecular , Inestabilidad Genómica , Heterocromatina/genética , Heterocromatina/metabolismo , Recombinación Homóloga , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/terapia , Telomerasa/genética , Telómero/genética , Transcripción Genética
11.
J Cell Biol ; 208(4): 415-28, 2015 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-25688135

RESUMEN

Telomeres and centromeres have traditionally been considered to perform distinct roles. During meiotic prophase, in a conserved chromosomal configuration called the bouquet, telomeres gather to the nuclear membrane (NM), often near centrosomes. We found previously that upon disruption of the fission yeast bouquet, centrosomes failed to insert into the NM at meiosis I and nucleate bipolar spindles. Hence, the trans-NM association of telomeres with centrosomes during prophase is crucial for efficient spindle formation. Nonetheless, in approximately half of bouquet-deficient meiocytes, spindles form properly. Here, we show that bouquet-deficient cells can successfully undergo meiosis using centromere-centrosome contact instead of telomere-centrosome contact to generate spindle formation. Accordingly, forced association between centromeres and centrosomes fully rescued the spindle defects incurred by bouquet disruption. Telomeres and centromeres both stimulate focal accumulation of the SUN domain protein Sad1 beneath the centrosome, suggesting a molecular underpinning for their shared spindle-generating ability. Our observations demonstrate an unanticipated level of interchangeability between the two most prominent chromosomal landmarks.


Asunto(s)
Centrómero/genética , Centrosoma/metabolismo , Meiosis , Schizosaccharomyces/genética , Huso Acromático/genética , Telómero/genética , Proteínas de Ciclo Celular/biosíntesis , Proteínas de Ciclo Celular/genética , Cromatina/genética , Cromosomas Fúngicos/genética , Dineínas/genética , Endorribonucleasas/genética , Proteínas Fluorescentes Verdes/biosíntesis , Proteínas Fluorescentes Verdes/genética , Membrana Nuclear/metabolismo , Proteínas Nucleares/genética , Schizosaccharomyces/citología , Proteínas de Schizosaccharomyces pombe/biosíntesis , Proteínas de Schizosaccharomyces pombe/genética , Proteínas de Schizosaccharomyces pombe/metabolismo , Proteínas de Unión a Telómeros/biosíntesis , Proteínas de Unión a Telómeros/genética
12.
Nature ; 467(7312): 223-7, 2010 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-20829796

RESUMEN

The notion that telomeres are essential for chromosome linearity stems from the existence of two chief dangers: inappropriate DNA damage response (DDR) reactions that mistake natural chromosome ends for double-strand DNA breaks (DSBs), and the progressive loss of DNA from chromosomal termini due to the end replication problem. Telomeres avert the former peril by binding sequence-specific end-protection factors that control the access of DDR activities. The latter threat is tackled by recruiting telomerase, a reverse transcriptase that uses an integral RNA subunit to template the addition of telomere repeats to chromosome ends. Here we describe an alternative mode of linear chromosome maintenance in which canonical telomeres are superseded by blocks of heterochromatin. We show that in the absence of telomerase, Schizosaccharomyces pombe cells can survive telomere sequence loss by continually amplifying and rearranging heterochromatic sequences. Because the heterochromatin assembly machinery is required for this survival mode, we have termed it 'HAATI' (heterochromatin amplification-mediated and telomerase-independent). HAATI uses the canonical end-protection protein Pot1 (ref. 4) and its interacting partner Ccq1 (ref. 5) to preserve chromosome linearity. The data suggest a model in which Ccq1 is recruited by the amplified heterochromatin and provides an anchor for Pot1, which accomplishes its end-protection function in the absence of its cognate DNA-binding sequence. HAATI resembles the chromosome end-maintenance strategy found in Drosophila melanogaster, which lacks specific telomere sequences but nonetheless assembles terminal heterochromatin structures that recruit end-protection factors. These findings reveal a previously unrecognized mode by which cancer cells might escape the requirement for telomerase activation, and offer a tool for studying genomes that sustain unusually high levels of heterochromatinization.


Asunto(s)
Cromosomas Fúngicos/metabolismo , Heterocromatina , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Telómero/metabolismo , Animales , Proteínas de Ciclo Celular/metabolismo , Drosophila melanogaster/metabolismo , N-Metiltransferasa de Histona-Lisina , Humanos , Metiltransferasas/metabolismo , Recombinasa Rad51/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Telomerasa/metabolismo
14.
Nature ; 440(7085): 824-8, 2006 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-16598261

RESUMEN

Telomere replication is achieved through the combined action of the conventional DNA replication machinery and the reverse transcriptase, telomerase. Telomere-binding proteins have crucial roles in controlling telomerase activity; however, little is known about their role in controlling semi-conservative replication, which synthesizes the bulk of telomeric DNA. Telomere repeats in the fission yeast Schizosaccharomyces pombe are bound by Taz1, a regulator of diverse telomere functions. It is generally assumed that telomere-binding proteins impede replication fork progression. Here we show that, on the contrary, Taz1 is crucial for efficient replication fork progression through the telomere. Using two-dimensional gel electrophoresis, we find that loss of Taz1 leads to stalled replication forks at telomeres and internally placed telomere sequences, regardless of whether the telomeric G-rich strand is replicated by leading- or lagging-strand synthesis. In contrast, the Taz1-interacting protein Rap1 is dispensable for efficient telomeric fork progression. Upon loss of telomerase, taz1Delta telomeres are lost precipitously, suggesting that maintenance of taz1Delta telomere repeats cannot be sustained through semi-conservative replication. As the human telomere proteins TRF1 and TRF2 are Taz1 orthologues, we predict that one or both of the human TRFs may orchestrate fork passage through human telomeres. Stalled forks at dysfunctional human telomeres are likely to accelerate the genomic instability that drives tumorigenesis.


Asunto(s)
Replicación del ADN , Proteínas de Schizosaccharomyces pombe/metabolismo , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Proteínas de Unión a Telómeros/metabolismo , Telómero/metabolismo , Proteínas de Unión al ADN/deficiencia , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Cinética , Proteínas de Schizosaccharomyces pombe/genética , Complejo Shelterina , Telomerasa/deficiencia , Telomerasa/genética , Telomerasa/metabolismo , Telómero/genética , Proteínas de Unión a Telómeros/deficiencia , Proteínas de Unión a Telómeros/genética , Moldes Genéticos
15.
Anal Chem ; 75(10): 2243-50, 2003 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-12918962

RESUMEN

A new approach for the analysis of particulate matter by radio frequency glow discharge optical emission spectrometry (rf-GD-OES) is described. Dispersion of the particles in a sol-gel sample matrix provides a convenient means of generating a thin film suitable for sputter-sampling into the discharge. Acid-catalyzed sol-gel glasses synthesized from tetramethyl orthosilicate were prepared and spun-cast on glass substrates. The resultant thin films on glass substrates were analyzed to determine the discharge operating conditions and resultant sputtering characteristics while a number of optical emission lines of the film components were monitored. Slurries of powdered standard reference materials NIST SRM 1884a (Portland Cement) and NIST SRM 2690 (Coal Fly Ash) dispersed in the sols were cast into films in the same manner. Use of the sol-gels as sample matrixes allows for background subtraction through the use of analytical blanks and may facilitate the generation of calibration curves via readily synthesized, matrix-matched analytical standards in solids analysis. Detection limits were determined for minor elements via the RSDB method to be in the range of 1-10 microg/g in Portland Cement and Coal Fly Ash samples for the elements Al, Fe, Mg, S, and Si. Values for Ca were in the range of 15-35 microg/g. This preliminary study demonstrates the possibility of incorporating various insoluble species, including ceramics and geological specimens in powder form, into a solid matrix for further analysis by either rf-GD-OES or MS.

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