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Importance: Despite the expansion of SARS-CoV-2 testing, available tests have not received Emergency Use Authorization for performance with self-collected anterior nares (nasal) swabs from children younger than 14 years because the effect of pediatric self-swabbing on SARS-CoV-2 test sensitivity is unknown. Objective: To characterize the ability of school-aged children to self-collect nasal swabs for SARS-CoV-2 testing compared with collection by health care workers. Design, Setting, and Participants: Cross-sectional study of 197 symptomatic children and adolescents aged 4 to 14 years old. Individuals were recruited based on results of testing in the Children's Healthcare of Atlanta system from July to August 2021. Exposures: Children and adolescents were given instructional material consisting of a short instructional video and a handout with written and visual steps for self-swab collection. Participants first provided a self-collected nasal swab. Health care workers then collected a second specimen. Main Outcomes and Measures: The primary outcome was SARS-CoV-2 detection and relative quantitation by cycle threshold (Ct) in self- vs health care worker-collected nasal swabs when tested with a real-time reverse transcriptase-polymerase chain reaction test with Emergency Use Authorization. Results: Among the study participants, 108 of 194 (55.7%) were male and the median age was 9 years (IQR, 6-11). Of the 196 participants, 87 (44.4%) tested positive for SARS-CoV-2 and 105 (53.6%) tested negative by both self- and health care worker-collected swabs. Two children tested positive by self- or health care worker-collected swab alone; 1 child had an invalid health care worker swab. Compared with health care worker-collected swabs, self-collected swabs had 97.8% (95% CI, 94.7%-100.0%) and 98.1% (95% CI, 95.6%-100.0%) positive and negative percent agreement, respectively, and SARS-CoV-2 Ct values did not differ significantly between groups (mean [SD] Ct, self-swab: 26.7 [5.4] vs health care worker swab: 26.3 [6.0]; P = .65). Conclusions and Relevance: After hearing and seeing simple instructional materials, children and adolescents aged 4 to 14 years self-collected nasal swabs that closely agreed on SARS-CoV-2 detection with swabs collected by health care workers.
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COVID-19 , SARS-CoV-2 , Adolescente , COVID-19/diagnóstico , Prueba de COVID-19 , Niño , Preescolar , Estudios Transversales , Femenino , Personal de Salud , Humanos , Masculino , Manejo de Especímenes/métodosRESUMEN
PURPOSE: The goal is to determine if variations exist between male and female blastocysts in preimplantation measurements of quality and ploidy and in vitro fertilization elective single-embryo transfer (eSET) outcomes. METHODS: A retrospective chart review was conducted from a private fertility center's database of blastocysts undergoing preimplantation genetic testing for aneuploidy, along with details of eSET from this screened cohort. Main outcomes included preimplantation embryo quality and sex-specific eSET outcomes. RESULTS: A total of 3708 embryos from 578 women were evaluated, with 45.9% male and 54.1% female. The majority were High grade. No difference existed between embryo sex and overall morphological grade, inner cell mass or trophectoderm grade, or blastocyst transformation day. Female blastocysts had a higher aneuploidy rate than male blastocysts (P < 0.001). Five hundred thirty-nine eSETs from 392 women were evaluated, with High grade embryos more likely to have implantation (P < 0.001), clinical pregnancy (P < 0.001), and ongoing pregnancy (P = 0.018) than Mid or Low grade embryos. Day 5 blastocysts were more likely to have implantation (P = 0.018), clinical pregnancy (P = 0.005), and ongoing pregnancy (P = 0.018) than day 6 blastocysts. Male and female embryos had similar transfer outcomes, although female day 5 blastocysts were more likely to result in clinical pregnancy (P = 0.012), but not ongoing pregnancy, than female day 6 blastocysts. Male eSET outcomes did not differ by blastocyst transformation day. CONCLUSION: Male and female embryos have comparable grade and quality; however, female embryos were more likely to be aneuploid. Ongoing pregnancy rates did not differ by embryo sex. Day 5 embryos had more favorable transfer outcomes than day 6 embryos.
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Blastocisto/citología , Transferencia de Embrión , Embrión de Mamíferos/citología , Fertilización In Vitro/métodos , Ploidias , Índice de Embarazo/tendencias , Diagnóstico Preimplantación/métodos , Adulto , Embrión de Mamíferos/metabolismo , Femenino , Pruebas Genéticas , Humanos , Masculino , Embarazo , Estudios RetrospectivosRESUMEN
Patients with systemic mastocytosis have an increased risk of osteoporosis, however, the risk of osteoporotic fractures among the classic chronic myeloproliferative neoplasms (CMPN), including essential thrombocythaemia (ET), polycythaemia vera (PV) and chronic myeloid leukaemia (CML), is unknown. We conducted a population-based cohort study to determine the risk of osteoporotic fractures among three cohorts of patients with newly diagnosed ET, PV, and CML. Patients were identified in medical registers including all Danish hospitals during 1980-2010 and were followed until first osteoporotic fracture. Fracture risk was compared to cohorts from the general population matched on age, sex and calendar year. We followed 7595 CMPN patients and 338 974 comparison cohort members. We found that the risk of femoral fracture after 5 years was consistently higher than the general population, being 3·01% (95% confidence interval (CI): 2·20-4·10), 4·74% (95%CI: 4·06-5·52) and 4·64% (95%CI: 3·29-6·53) among ET, PV, and CML patients respectively. Adjusted hazard ratio for femoral fracture was increased 1·19-fold (95% CI: 0·94-1·51) for ET patients, 1·82-fold (95% CI: 1·62-2·04) for PV patients, and 2·67-fold (95% CI: 1·97-3·62) for CML patients. We conclude that CMPN patients are at higher risk of osteoporotic fractures than the general population.
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Fracturas Espontáneas/etiología , Leucemia Mielógena Crónica BCR-ABL Positiva/complicaciones , Osteoporosis/etiología , Policitemia Vera/complicaciones , Trombocitemia Esencial/complicaciones , Adulto , Anciano , Trastornos Relacionados con Alcohol/epidemiología , Comorbilidad , Dinamarca/epidemiología , Femenino , Estudios de Seguimiento , Fracturas Espontáneas/epidemiología , Fracturas de Cadera/epidemiología , Fracturas de Cadera/etiología , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Riesgo , Fumar/epidemiología , Adulto JovenRESUMEN
DNA double-strand breaks (DSB) can arise during DNA replication, or after exposure to DNA-damaging agents, and their correct repair is fundamental for cell survival and genomic stability. Here, we show that the Smc5-Smc6 complex is recruited to DSBs de novo to support their repair by homologous recombination between sister chromatids. In addition, we demonstrate that Smc5-Smc6 is necessary to suppress gross chromosomal rearrangements. Our findings show that the Smc5-Smc6 complex is essential for genome stability as it promotes repair of DSBs by error-free sister-chromatid recombination (SCR), thereby suppressing inappropriate non-sister recombination events.
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Proteínas de Ciclo Celular/fisiología , Daño del ADN , Proteínas de Saccharomyces cerevisiae/fisiología , Saccharomyces cerevisiae/fisiología , Intercambio de Cromátides Hermanas , ADN/metabolismo , Desoxirribonucleasas de Localización Especificada Tipo II/metabolismo , Inestabilidad Genómica , Saccharomyces cerevisiae/genéticaRESUMEN
Background: Increased patient utilization of cannabidiol (CBD) leads to potential drug interactions with various medications and questions posed to pharmacists. Objective: To quantify the knowledge gap of pharmacists on CBD and CBD-containing products and assess the degree a continuing pharmacy education (CPE) program alters pharmacist confidence and competency on CBD knowledge. Methods: A 1-h CPE activity was offered as a home study from May 9, 2022, through September 30, 2022. Subjects were practicing pharmacy preceptors in Alabama who completed the pre-survey and post-survey for inclusion in matched-pair analyses. The primary outcome measure was participant score improvement between the pre-post surveys. Secondary measures involved pre-post comparisons on self-rated Likert questions concerning participant confidence in counseling, answering drug information questions, and ensuring patient safety regarding CBD. Results: A total of 124 participants completed the course. After matched pairing, 64 and 56 individuals were included in the knowledge-based and confidence ranking analyses, respectively. Participant scoring improved on the knowledge-based questions between the pre-post surveys (50.0% vs 87.8%, P < .001). There was a significant confidence improvement of participants from baseline on counseling patients about prescription or over-the-counter CBD products, answering questions from other healthcare professionals about these products, and ensuring patient safety while using these products (Average 5-level Likert scale increases of 1.75, 1.73, 1.70, respectively; all P < .001). Conclusion: Implementation of a CPE program improved practicing pharmacists' knowledge on information about CBD, which lead to increased competency on counseling patients, answering drug information questions, and promoting patient safety.
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Engineering plays a critical role in the development of medical devices, and this has been magnified since 2020 as severe acute respiratory syndrome coronavirus 2 swept over the globe. In response to the coronavirus disease 2019, the National Institutes of Health launched the Rapid Acceleration of Diagnostics (RADx) initiative to help meet the testing needs of the United States and effectively manage the pandemic. As the Engineering and Human Factors team for the RADx Tech Test Verification Core, we directly assessed more than 30 technologies that ultimately contributed to an increase of the country's total testing capacity by 1.7 billion tests to date. In this review, we present central lessons learned from this "apples-to-apples" comparison of novel, rapidly developed diagnostic devices. Overall, the evaluation framework and lessons learned presented in this review may serve as a blueprint for engineers developing point-of-care diagnostics, leaving us better prepared to respond to the next global public health crisis rapidly and effectively.
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COVID-19 , Humanos , Estados Unidos , COVID-19/diagnóstico , COVID-19/epidemiología , Técnicas de Laboratorio Clínico , SARS-CoV-2 , Prueba de COVID-19 , Pruebas en el Punto de AtenciónRESUMEN
Structure chromosome (SMC) proteins organize the core of cohesin, condensin and Smc5-Smc6 complexes. The Smc5-Smc6 complex is required for DNA repair, as well as having another essential but enigmatic function. Here, we generated conditional mutants of SMC5 and SMC6 in budding yeast, in which the essential function was affected. We show that mutant smc5-6 and smc6-9 cells undergo an aberrant mitosis in which chromosome segregation of repetitive regions is impaired; this leads to DNA damage and RAD9-dependent activation of the Rad53 protein kinase. Consistent with a requirement for the segregation of repetitive regions, Smc5 and Smc6 proteins are enriched at ribosomal DNA (rDNA) and at some telomeres. We show that, following Smc5-Smc6 inactivation, metaphase-arrested cells show increased levels of X-shaped DNA (Holliday junctions) at the rDNA locus. Furthermore, deletion of RAD52 partially suppresses the temperature sensitivity of smc5-6 and smc6-9 mutants. We also present evidence showing that the rDNA segregation defects of smc5/smc6 mutants are mechanistically different from those previously observed for condensin mutants. These results point towards a role for the Smc5-Smc6 complex in preventing the formation of sister chromatid junctions, thereby ensuring the correct partitioning of chromosomes during anaphase.
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Proteínas de Ciclo Celular/fisiología , Segregación Cromosómica/fisiología , Secuencias Repetitivas de Ácidos Nucleicos/fisiología , Proteínas de Saccharomyces cerevisiae/fisiología , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Cromatina/genética , Cromatina/fisiología , Proteínas Cromosómicas no Histona , Segregación Cromosómica/genética , Cromosomas/genética , Reparación del ADN/genética , Reparación del ADN/fisiología , ADN Ribosómico/genética , ADN Ribosómico/fisiología , Proteínas Fúngicas , Mutación , Proteínas Nucleares/genética , Proteínas Nucleares/fisiología , Secuencias Repetitivas de Ácidos Nucleicos/genética , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Factores de Tiempo , CohesinasRESUMEN
Among the mutations arising in the DMD gene and causing Duchenne Muscular Dystrophy (DMD), 10-15% are multi-exon duplications. There are no current therapeutic approaches with the ability to excise large multi-exon duplications, leaving this patient cohort without mutation-specific treatment. Using CRISPR/Cas9 could provide a valid alternative to achieve targeted excision of genomic duplications of any size. Here we show that the expression of a single CRISPR/Cas9 nuclease targeting a genomic region within a DMD duplication can restore the production of wild-type dystrophin in vitro. We assessed the extent of dystrophin repair following both constitutive and transient nuclease expression by either transducing DMD patient-derived myoblasts with integrating lentiviral vectors or electroporating them with CRISPR/Cas9 expressing plasmids. Comparing genomic, transcript and protein data, we observed that both continuous and transient nuclease expression resulted in approximately 50% dystrophin protein restoration in treated myoblasts. Our data demonstrate that a high transient expression profile of Cas9 circumvents its requirement of continuous expression within the cell for targeting DMD duplications. This proof-of-concept study therefore helps progress towards a clinically relevant gene editing strategy for in vivo dystrophin restoration, by highlighting important considerations for optimizing future therapeutic approaches.
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Sistemas CRISPR-Cas , Distrofia Muscular de Duchenne , Sistemas CRISPR-Cas/genética , Distrofina/genética , Distrofina/metabolismo , Endonucleasas/genética , Edición Génica/métodos , Terapia Genética/métodos , Humanos , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/metabolismo , Distrofia Muscular de Duchenne/terapia , Mioblastos/metabolismoRESUMEN
During the COVID-19 pandemic, the development of point-of-care (POC) diagnostic testing accelerated in an unparalleled fashion. As a result, there has been an increased need for accurate, robust, and easy-to-use POC testing in a variety of non-traditional settings (i.e., pharmacies, drive-thru sites, schools). While stakeholders often express the desire for POC technologies that are "as simple as digital pregnancy tests," there is little discussion of what this means in regards to device design, development, and assessment. The design of POC technologies and systems should take into account the capabilities and limitations of the users and their environments. Such "human factors" are important tenets that can help technology developers create POC technologies that are effective for end-users in a multitude of settings. Here, we review the core principles of human factors and discuss lessons learned during the evaluation process of SARS-CoV-2 POC testing.
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COVID-19 , Femenino , Humanos , COVID-19/diagnóstico , Pandemias , SARS-CoV-2/genética , Pruebas en el Punto de Atención , Sistemas de Atención de PuntoRESUMEN
Faced with the COVID-19 pandemic, the US system for developing and testing technologies was challenged in unparalleled ways. This article describes the multi-institutional, transdisciplinary team of the "RADxSM Tech Test Verification Core" and its role in expediting evaluations of COVID-19 testing devices. Expertise related to aspects of diagnostic testing was coordinated to evaluate testing devices with the goal of significantly expanding the ability to mass screen Americans to preserve lives and facilitate the safe return to work and school. Focal points included: laboratory and clinical device evaluation of the limit of viral detection, sensitivity, and specificity of devices in controlled and community settings; regulatory expertise to provide focused attention to barriers to device approval and distribution; usability testing from the perspective of patients and those using the tests to identify and overcome device limitations, and engineering assessment to evaluate robustness of design including human factors, manufacturability, and scalability.
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While there has been significant progress in the development of rapid COVID-19 diagnostics, as the pandemic unfolds, new challenges have emerged, including whether these technologies can reliably detect the more infectious variants of concern and be viably deployed in non-clinical settings as "self-tests". Multidisciplinary evaluation of the Abbott BinaxNOW COVID-19 Ag Card (BinaxNOW, a widely used rapid antigen test, included limit of detection, variant detection, test performance across different age-groups, and usability with self/caregiver-administration. While BinaxNOW detected the highly infectious variants, B.1.1.7 (Alpha) first identified in the UK, B.1.351 (Beta) first identified in South Africa, P.1 (Gamma) first identified in Brazil, B.1.617.2 (Delta) first identified in India and B.1.2, a non-VOC, test sensitivity decreased with decreasing viral loads. Moreover, BinaxNOW sensitivity trended lower when devices were performed by patients/caregivers themselves compared to trained clinical staff, despite universally high usability assessments following self/caregiver-administration among different age groups. Overall, these data indicate that while BinaxNOW accurately detects the new viral variants, as rapid COVID-19 tests enter the home, their already lower sensitivities compared to RT-PCR may decrease even more due to user error.
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Prueba Serológica para COVID-19 , COVID-19/diagnóstico , Sistemas de Atención de Punto , Autoevaluación , Humanos , Límite de Detección , SARS-CoV-2 , Sensibilidad y EspecificidadRESUMEN
Patients with no history of melanoma occasionally present with apparently metastatic melanoma in the lungs, but have no evidence of a primary melanoma. The aims of this study were to investigate the role of surgical resection in the treatment of such patients, and to examine the evidence for a diagnosis of primary pulmonary melanoma in each case. Patients with an unknown primary melanoma who presented with pulmonary disease and subsequently underwent surgical resection were identified from the Sydney Melanoma Unit database. Fifteen patients fulfilled the study criteria. Multiple lesions were present in four. Eight wedge resections and 10 lobectomies were performed. The patients' median survival was 32 months and the 5-year actuarial survival was 42%. This compares with the overall Sydney Melanoma Unit experience of lung resection for melanoma in 83 patients, where the median survival was 19 months and the 5-year survival was 22%. Resection of pulmonary disease in melanoma patients with an unknown primary lesion can result in long-term survival, and even apparent cure. It is possible that some of the patients in this series had primary melanoma of the lung, but this is impossible to prove.
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Neoplasias Pulmonares/secundario , Neoplasias Pulmonares/cirugía , Melanoma/secundario , Melanoma/cirugía , Neoplasias Primarias Desconocidas/patología , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Resultado del TratamientoAsunto(s)
Quistes/complicaciones , Trastornos de Deglución/etiología , Enfermedades Faríngeas/complicaciones , Faringe/diagnóstico por imagen , Anciano , Quistes/diagnóstico , Trastornos de Deglución/diagnóstico , Femenino , Humanos , Imagen por Resonancia Magnética , Enfermedades Faríngeas/diagnóstico , Tomografía Computarizada por Rayos XRESUMEN
Patients with the classical Philadelphia chromosome-negative chronic myeloproliferative neoplasms including essential thrombocythemia, polycythemia vera and primary myelofibrosis often suffer from comorbidities, in particular, cardiovascular diseases and thrombotic events. Apparently, there is also an increased risk of osteoporotic fractures among these patients. However, the true prevalence, mechanisms involved and therapeutic implications are not well described. In this review, we summarize what is currently known about possible associations between bone disease and chronic myeloproliferative neoplasms. Chronic inflammation has been suggested to explain the initiation of clonal development and progression in chronic myeloproliferative neoplasms. Decreased bone mineral density and enhanced fracture risk are well-known manifestations of many chronic systemic inflammatory diseases. As opposed to systemic mastocytosis (SM) where pathogenic mechanisms for bone manifestations probably involve effects of mast cell mediators on bone metabolism, the mechanisms responsible for increased fracture risk in other chronic myeloproliferative neoplasms are not known.
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Enfermedades Óseas/complicaciones , Trastornos Mieloproliferativos/complicaciones , Densidad Ósea , Enfermedades Óseas/diagnóstico , Enfermedades Óseas/terapia , Enfermedad Crónica , Humanos , Trastornos Mieloproliferativos/diagnóstico , Trastornos Mieloproliferativos/terapia , Resultado del TratamientoRESUMEN
Primary myelofibrosis (MF) is a severe chronic myeloproliferative neoplasm, progressing towards a terminal stage with insufficient haematopoiesis and osteosclerotic manifestations. Whilst densitometry studies have showed MF patients to have elevated bone mineral density, data on bone geometry and micro-structure assessed with non-invasive methods are lacking. We measured areal bone mineral density (aBMD) using dual-energy X-ray absorptiometry (DXA). Bone geometry, volumetric BMD, and micro-architecture were measured using high-resolution peripheral quantitative computed tomography (HR-pQCT). We compared the structural parameters of bones by comparing 18 patients with MF and healthy controls matched for age, sex, and height. Blood was analysed for biochemical markers of bone turnover in patients with MF. There were no significant differences in measurements of bone geometry, volumetric bone mineral density, and micro-structure between MF patients and matched controls. Estimated bone stiffness and bone strength were similar between MF patients and controls. The level of pro-collagen type 1 N-terminal pro-peptide (P1NP) was significantly increased in MF, which may indicate extensive collagen synthesis, one of the major diagnostic criteria in MF. We conclude that bone mineral density, geometry, and micro-architecture in this cohort of MF patients are comparable with those in healthy individuals.
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Densidad Ósea , Remodelación Ósea , Huesos/metabolismo , Huesos/patología , Mielofibrosis Primaria/metabolismo , Mielofibrosis Primaria/patología , Absorciometría de Fotón , Anciano , Biomarcadores , Médula Ósea/patología , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mielofibrosis Primaria/diagnóstico , Reproducibilidad de los Resultados , Tomografía Computarizada por Rayos XRESUMEN
Polycythaemia vera, essential thrombocytosis and primary myelofibrosis are closely related, clonal myeloproliferative neoplasms. Our knowledge of the underlying molecular mechanisms driving these diseases has increased dramatically during the latest ten years. Traditionally, treatment of these malignancies has focused on lowering their inherent thromboembolic risk but with the discovery of the JAK2-V617F mutation and most recently the calreticulin mutations new therapeutic options such as interferon-alpha, JAK2-inhibitors and statins are being contemplated. This article reviews these new treatment options.
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Trastornos Mieloproliferativos/tratamiento farmacológico , Algoritmos , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Interferón-alfa/uso terapéutico , Janus Quinasa 2/antagonistas & inhibidores , Policitemia Vera/tratamiento farmacológico , Mielofibrosis Primaria/tratamiento farmacológico , Trombocitosis/tratamiento farmacológicoRESUMEN
This case report is about severe osteoporosis in a woman known with polycythaemia vera (PV). A 51-year-old woman with hereditary predisposition to osteoporosis had a dual X-ray absorptiometry scan without osteoporosis. Only one year later she was diagnosed with PV. Re-scan eight years later showed progression to severe osteoporosis. Whether this is secondary osteoporosis, initiated or accelerated by the presence of PV is not known. A recent Danish registry study has shown that PV patients have an increased incidence of fractures compared with the general population.
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Osteoporosis/complicaciones , Policitemia Vera/complicaciones , Femenino , Fracturas por Compresión/diagnóstico , Fracturas por Compresión/etiología , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Osteoporosis/diagnóstico , Osteoporosis/tratamiento farmacológico , Fracturas Osteoporóticas/diagnóstico , Fracturas Osteoporóticas/etiología , Policitemia Vera/diagnóstico , Policitemia Vera/tratamiento farmacológico , Fracturas de la Columna Vertebral/diagnóstico , Fracturas de la Columna Vertebral/etiologíaRESUMEN
G1-S transcriptional control involves the coordination of the expression of a large set of co-regulated genes as a function of cell cycle progression (Bertoli et al., Nat Rev Mol Cell Biol 14:518-528, 2013). Confining transcription to the G1 phase of the cell cycle requires the regulation of specific transcription factor activity through either co-factors or regulation of promoter DNA binding. Therefore, the analysis of G1-S transcriptional control involves cell cycle synchronization and monitoring cell cycle synchrony, in order to establish DNA binding of G1-S transcription factors to G1-S promoters and to investigate changes in gene expression during the different phases of the cell cycle. Here, we describe a cell cycle synchrony method and ways to monitor synchrony. We also describe a chromatin immunoprecipitation (ChIP) method to locate G1-S transcription factor components to promoters and a quantitative PCR (qPCR) protocol to determine gene expression. Defining the binding dynamics of G1-S transcription factors and changes in gene expression during the cell cycle should provide new insights into the mechanism that control G1-S transcription and will allow for investigation of the biological relevance of confining gene expression to G1.
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Fase G1 , Fase S , Saccharomycetales/citología , Activación Transcripcional , Técnicas de Cultivo de Célula/métodos , Inmunoprecipitación de Cromatina/métodos , Citometría de Flujo/métodos , Regulación Fúngica de la Expresión Génica , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Saccharomycetales/genéticaRESUMEN
PURPOSE: This study's purpose was to evaluate microleakage of two types of glass ionomer (GI) and composite restorations with saliva contamination at different stages of restorative procedures. METHODS: Extracted teeth with Class V cavities were restored with a conventional GI, nanofilled RMGI, or total-etched composite. The preparations were contaminated with saliva before the adhesive/primer application or before the restoration placement (N=10). The restored teeth were thermocycled (1000X), stained (basic fuchsin), and sectioned. Microleakage distance was measured and subjected to analysis of variance and Duncan's post-hoc test (P=.05). RESULTS: For the enamel margin, no significant difference was found between the conventional GI and composite restoration, with or without saliva contamination (P>.05). The nanofilled RMGI with contamination before restoration had the highest microleakage. For the cementum margin, composite had significantly more microleakage than both types of GI restorations, regardless of saliva contamination. CONCLUSIONS: Conventional and resin-modified glass ionomer restorations had less cementum microleakage, while the composite had less enamel microleakage. Saliva contamination did not affect microleakage of the conventional GI at either enamel or cementum margins. The nanofilled RMGI system was not sensitive to saliva contamination at the gingival margin, but had increased microleakage at the enamel margin, especially after the primer application.