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Genética Médica , Pruebas Prenatales no Invasivas , Embarazo , Femenino , Estados Unidos , Humanos , Diagnóstico Prenatal , Aberraciones Cromosómicas , GenómicaRESUMEN
Objective: To evaluate sick leave after meniscal repair vs arthroscopic partial meniscectomy (APM) and, for comparison, vs the general population. Method: Using Swedish register data we included all employed persons aged 19-49 years in the general population of Skåne region and identified those having had meniscus repair or APM in the period of 2005-2012. We retrieved data on sick leave during 1 year before until 2 years after surgery. We used logistic regression to estimate the risk differences of being on sick leave and negative binomial model to analyze differences in the number of days on sick leave. Results: We included 192 persons with meniscus repair, 2481 with APM, and 376 â345 references without meniscus surgery. Of these, 55% of meniscus repair group, 43% of APM group had any sick leave in the 2-year period following the surgery, while 17% of the references were on sick leave in the corresponding period. The mean (SD) number of days of sick leave after meniscus repair was 55 (77) days and for APM 37 (86) days. Meniscus repair was associated with higher probability of sick leave compared to APM with an adjusted risk difference of 0.13 (95% CI 0.07-0.19). Conclusion: Persons undergoing meniscus repair have more frequent and 37% longer periods of sick leave in the short term than persons undergoing APM. However, sick leave in the long-term warrant further attention as successful repair may be associated with less knee osteoarthritis development than APM.
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PURPOSE: Patient-controlled sedation (PCS) allows patients to self-administer sedative drugs during endoscopic retrograde cholangiopancreatography (ERCP). There is a paucity of research on the experiences of patients who used PCS. Therefore the purpose of this study was to describe the perioperative experiences of patients who used PCS during ERCP. DESIGN: Prospective study using semi-structured interviews. METHODS: Qualitative content analysis facilitated a latent understanding of the manifest content. FINDINGS: Eleven interviews revealed three main themes and underlying categories that summarized the patient experience: participation (control and perioperative sedation); communication (personnel, information, safety, insecurity, and concern); and sensation (effects and side effects). CONCLUSIONS: The participatory experience of PCS resulted not from the opportunity for patient involvement but, rather, the establishment of a patient-professional relationship. Specifically, the interactions between patients and health care professionals played a vital role in the patients' overall experience of PCS.
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Sedación Consciente , Propofol , Humanos , Sedación Consciente/efectos adversos , Sedación Consciente/métodos , Estudios Prospectivos , Colangiopancreatografia Retrógrada Endoscópica/efectos adversos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Investigación Cualitativa , Hipnóticos y SedantesRESUMEN
BACKGROUND: There is a significant variability in reported fetal fraction (FF), a common cause for no-calls in cell-free (cf)DNA based non-invasive prenatal screening. We examine the effect of imprecision in FF measurement on the performance of cfDNA screening for Down syndrome, when low FF samples are classified as no-calls. METHODS: A model for the reported FF was constructed from the FF measurement precision and the underlying true FF. The model was used to predict singleton Down syndrome detection rates (DRs) for various FF cut-offs and underlying discriminatory powers of the test. RESULTS: Increasing the FF cut-off led to slightly increased apparent DR, when no-calls are excluded, and an associated larger decrease in effective DR, when no-calls are included. These effects were smaller for tests with higher discriminatory power and larger as maternal weight increased. CONCLUSIONS: Most no-calls due to a low reported FF have a true FF above the cut-off. The discriminatory power of a test limits its effective DR and FF precision determines the tradeoff between apparent and effective DR when low FF is used to discard samples. Tests with high discriminatory power do not benefit from current FF measurements.
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Ácidos Nucleicos Libres de Células , Síndrome de Down , Síndrome de Down/diagnóstico , Femenino , Feto , Humanos , Embarazo , Atención Prenatal , Diagnóstico PrenatalRESUMEN
A surveillance strategy of the heritable TP53-related cancer syndrome (hTP53rc), commonly referred to as the Li-Fraumeni syndrome (LFS), is studied in a prospective observational nationwide multi-centre study in Sweden (SWEP53). The aim of this sub-study is to evaluate whole-body MRI (WB-MRI) regarding the rate of malignant, indeterminate, and benign imaging findings and the associated further workup generated by the baseline examination. Individuals with hTP53rc were enrolled in a surveillance program including annual whole-body MRI (WB-MRI), brain-MRI, and in female carriers, dedicated breast MRI. A total of 68 adults ≥18 years old have been enrolled to date. Of these, 61 fulfilled the inclusion criteria for the baseline MRI scan. In total, 42 showed a normal scan, while 19 (31%) needed further workup, of whom three individuals (3/19 = 16%) were diagnosed with asymptomatic malignant tumours (thyroid cancer, disseminated upper GI cancer, and liver metastasis from a previous breast cancer). Forty-three participants were women, of whom 21 had performed risk-reducing mastectomy prior to inclusion. The remaining were monitored with breast MRI, and no breast tumours were detected on baseline MRI. WB-MRI has the potential to identify asymptomatic tumours in individuals with hTP53rc syndrome. The challenge is to adequately and efficiently investigate all indeterminate findings. Thus, a multidisciplinary team should be considered in surveillance programs for individuals with hTP53rc syndrome.
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BACKGROUND: Noninvasive prenatal genetic testing (NIPT) has been adopted as the first choice for aneuploidy screening. The purposes of this study were to investigate the accuracy of Vanadis® NIPT (hereafter CRITO-NIPT) in order to gain a deeper insight into the reasons for discrepancies, as well as to discuss the role of fetal ultrasound. METHODS: Between 2019 and 2020, CRITO-NIPT was performed in 1218 cases of patients who underwent CVS or amniocentesis after a detailed fetal ultrasound exam and genetic counseling. The CRITO-NIPT results were compared with the genetic results. In cases of test discrepancies, the placentae were collected for detailed genetic research, and the pre-procedure fetal ultrasound findings were referred to. RESULTS: The positive predictive value of T21, T18, and T13 was 93.55%, 88.46%, and 100%, respectively. In 90% of the of false positive (FP) cases, the placentae were examined. In 75% of the CRITO FP-T21 cases, placental mosaicism, or a demised twin's T21, were confirmed. There were complicated mosaic cases, including tetrasomy 21/trisomy7 and monosomy 21/trisomy21 cases. In one of three no-call cases, an intermediate deletion of chromosome 13 was detected. CONCLUSIONS: The CRITO study investigated the mechanism of false positives, and the detailed mechanisms in mosaic and no-call cases. There have hitherto been no reports that have provided insight by partitioning the placenta to compare the NIPT and invasive test results, nor that have provided detailed ultrasound findings in the cases of discordant results, revealing the demonstrated importance of, and necessity for, detailed ultrasonography. This article describes the potential of rolling-circle replication as a powerful biosensing platform, as well as the importance of examining the fetus in detail with ultrasound. However, we should remember that the potential applications raise ethical and social concerns that go beyond aneuploidy and its methodology.
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Background: Rolling-circle replication (RCR) is a novel technology that has not been applied to cell-free DNA (cfDNA) testing until recently. Given the cost and simplicity advantages of this technology compared to other platforms currently used in cfDNA analysis, an assessment of RCR in clinical laboratories was performed. Here, we present the first validation study from clinical laboratories utilizing RCR technology. Methods: 831 samples from spontaneously pregnant women carrying a singleton fetus, and 25 synthetic samples, were analyzed for the fetal risk of trisomy 21 (T21), trisomy 18 (T18) and trisomy 13 (T13), by three laboratories on three continents. All the screen-positive pregnancies were provided post-test genetic counseling and confirmatory diagnostic invasive testing (e.g., amniocentesis). The screen-negative pregnancies were routinely evaluated at birth for fetal aneuploidies, using newborn examinations, and any suspected aneuploidies would have been offered diagnostic testing or confirmed with karyotyping. Results: The study found rolling-circle replication to be a highly viable technology for the clinical assessment of fetal aneuploidies, with 100% sensitivity for T21 (95% CI: 82.35-100.00%); 100.00% sensitivity for T18 (71.51-100.00%); and 100.00% sensitivity for T13 analyses (66.37-100.00%). The specificities were >99% for each trisomy (99.7% (99.01-99.97%) for T21; 99.5% (98.62-99.85%) for T18; 99.7% (99.03-99.97%) for T13), along with a first-pass no-call rate of 0.93%. Conclusions: The study showed that using a rolling-circle replication-based cfDNA system for the evaluation of the common aneuploidies would provide greater accuracy and clinical utility compared to conventional biochemical screening, and it would provide comparable results to other reported cfDNA methodologies.
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Aneuploidia , Ácidos Nucleicos Libres de Células/sangre , Síndrome de Down/diagnóstico , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Pruebas Prenatales no Invasivas/métodos , Síndrome de la Trisomía 13/diagnóstico , Síndrome de la Trisomía 18/diagnóstico , Adulto , Ácidos Nucleicos Libres de Células/genética , Síndrome de Down/genética , Femenino , Humanos , Persona de Mediana Edad , Embarazo , Síndrome de la Trisomía 13/genética , Síndrome de la Trisomía 18/genética , Adulto JovenRESUMEN
BACKGROUND: Fetal fraction is often used to designate no-calls in noninvasive prenatal screening (NIPS). We wished to compare the variability in determining fetal fraction to gold standard methods. METHODS: We identified 6 publications with datasets consisting of methods capable of measuring fetal fraction for all samples that also had comparison data from gold standard methods. Examples of gold standard methods included relative Y-chromosome quantification in cases of male fetus pregnancies or relative quantification of the relevant chromosome for pregnancies affected by one of the 3 major trisomies. RESULTS: The studies showed that the differences of the various fetal fraction measurement assays as compared to a gold standard measurement displayed a standard deviation (SD) in the range of 1.3-3.4% fetal fraction (FF). The 4 studies that measured FF from fragment size and genomic coordinates or single nucleotide polymorphisms had a lower variability, with a median SD of about 1.6%, whereas 2 other studies using different methods displayed significantly higher variability. CONCLUSION: When deciding whether to use the reported FF as a reason to discard samples as no-calls or not, we recommend taking the variability of the FF measurement into consideration.
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Ácidos Nucleicos Libres de Células , Pruebas Prenatales no Invasivas , Femenino , Feto , Genoma , Humanos , Masculino , Embarazo , Atención PrenatalRESUMEN
OBJECTIVE: To evaluate clinical performance of a new automated cell-free (cf)DNA assay in maternal plasma screening for trisomies 21, 18, and 13, and to determine fetal sex. METHOD: Maternal plasma samples from 1200 singleton pregnancies were analyzed with a new non-sequencing cfDNA method, which is based on imaging and counting specific chromosome targets. Reference outcomes were determined by either cytogenetic testing, of amniotic fluid or chorionic villi, or clinical examination of neonates. RESULTS: The samples examined included 158 fetal aneuploidies. Sensitivity was 100% (112/112) for trisomy 21, 89% (32/36) for trisomy 18, and 100% (10/10) for trisomy 13. The respective specificities were 100%, 99.5%, and 99.9%. There were five first pass failures (0.4%), all in unaffected pregnancies. Sex classification was performed on 979 of the samples and 99.6% (975/979) provided a concordant result. CONCLUSION: The new automated cfDNA assay has high sensitivity and specificity for trisomies 21, 18, and 13 and accurate classification of fetal sex, while maintaining a low failure rate. The study demonstrated that cfDNA testing can be simplified and automated to reduce cost and thereby enabling wider population-based screening.
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Pruebas Prenatales no Invasivas/métodos , Trisomía/diagnóstico , Cromosomas Humanos Par 13 , Cromosomas Humanos Par 18 , Cromosomas Humanos Par 21 , Femenino , Humanos , EmbarazoRESUMEN
Cell-free DNA analysis is becoming adopted for first line aneuploidy screening, however for most healthcare programs, cost and workflow complexity is limiting adoption of the test. We report a novel cost effective method, the Vanadis NIPT assay, designed for high precision digitally-enabled measurement of chromosomal aneuploidies in maternal plasma. Reducing NIPT assay complexity is achieved by using novel molecular probe technology that specifically label target chromosomes combined with a new readout format using a nanofilter to enrich single molecules for imaging and counting without DNA amplification, microarrays or sequencing. The primary objective of this study was to assess the Vanadis NIPT assay with respect to analytical precision and clinical feasibility. Analysis of reference DNA samples indicate that samples which are challenging to analyze with low fetal-fraction can be readily detected with a limit of detection determined at <2% fetal-fraction. In total of 286 clinical samples were analysed and 30 out of 30 pregnancies affected by trisomy 21 were classified correctly. This method has the potential to make cost effective NIPT more widely available with more women benefiting from superior detection and false positive rates.
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Ácidos Nucleicos Libres de Células/sangre , Síndrome de Down/diagnóstico , Diagnóstico Prenatal/métodos , Imagen Individual de Molécula/métodos , Aneuploidia , Estudios de Casos y Controles , Análisis Costo-Beneficio , Femenino , Humanos , Embarazo , Diagnóstico Prenatal/economía , Estudios Prospectivos , Imagen Individual de Molécula/economíaRESUMEN
Stretching of DNA in nanoscale confinement allows for several important studies. The genetic contents of the DNA can be visualized on the single DNA molecule level and both the polymer physics of confined DNA and also DNA/protein and other DNA/DNA-binding molecule interactions can be explored. This chapter describes the basic steps to fabricate the nanostructures, perform the experiments and analyze the data.
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ADN/química , Microscopía Fluorescente/métodos , Nanoestructuras/química , Nanotecnología/métodosRESUMEN
The number of patients with multiple primary malignancies has been increasing steadily in recent years. In the present study, we describe a unique case of an 81-year-old woman with 5 metachronous and synchronous primary malignant neoplasms. The patient was first diagnosed with an endometrium adenocarcinoma in 1997 and a colon adenocarcinoma in 2002. Eleven years after her colon surgery, in 2013, the patient presented with 3 other primary malignancies within a 4-month time span: an invasive malignant melanoma on the lower leg, an invasive mucinous breast carcinoma in the right breast, and a pleomorphic spindle cell sarcoma on the left upper arm. Subsequent routine medical checkups in 2013-2017 revealed no metastases of the primary malignancies. The patient mentioned a familial aggregation of malignant tumors, including 2 sisters with breast cancer and a brother with lung cancer. Interestingly, next-generation sequencing analysis of the patient's blood sample detected no mutations in the BRCA1, BRCA2, TP53, PTEN, CDH1, PALB2, RAD51C, RAD51D, MLH1, MSH2, MSH6, PMS2, EPCAM, APC, MUTYH, STK11, BMPR1A, SMAD4, PTEN, POLE, POLD1, GREM1, and GALNT12 genes. Therefore, whole genome sequencing is warranted to identify cancer-related genetic alterations in this patient with quintuple primary malignancies.
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The incidence of synchronous bilateral breast carcinomas (BBCs) has increased with a more frequent use of magnetic resonance imaging screening of the contralateral breast in women with newly diagnosed breast cancer. A total of 30% of all BBCs occur synchronously. In the present study, we describe a unique case of synchronous BBC in a 59-year-old previously healthy woman with no known family history of breast or ovarian cancer. At the time of diagnosis the patient had an invasive lobular carcinoma (ILC) in the right breast and an adenoid cystic carcinoma (ACC) in the left breast. To the best of our knowledge, this is the first published case of bilateral, simultaneously occurring ACC and ILC of the breast. Genome-wide genomic profiling of the tumors revealed that they had distinctly different genomic imbalances. The ACC had a 5.7 Mb interstitial 6q deletion with a breakpoint located in the 3'-part of MYB, resulting in loss of the last coding exon of MYB and its 3'-UTR. RT-PCR analysis confirmed that the tumor expressed an ACC-specific MYB-NFIB fusion transcript. In contrast, the ILC had no rearrangements of 6q or MYB-NFIB gene fusion but showed instead gain of 1q21.1-qter, loss of 16q11.2-qter, and 22q12.2-q12.3 as the sole genomic imbalances. Notably, concurrent gains of 1q and losses of 16q are characteristic features of ILC. Collectively, our findings indicate that the ACC and ILC had originated independently of each other and that the MYB-NFIB fusion is a specific biomarker for breast ACC.
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RAD51 is the key component of the homologous recombination pathway in eukaryotic cells and performs its task by forming filaments on DNA. In this study we investigate the physical properties of RAD51 filaments formed on DNA using nanofluidic channels and fluorescence microscopy. Contrary to the bacterial ortholog RecA, RAD51 forms inhomogeneous filaments on long DNA in vitro, consisting of several protein patches. We demonstrate that a permanent "kink" in the filament is formed where two patches meet if the stretch of naked DNA between the patches is short. The kinks are readily seen in the present microscopy approach but would be hard to identify using conventional single DNA molecule techniques where the DNA is more stretched. We also demonstrate that protein patches separated by longer stretches of bare DNA roll up on each other and this is visualized as transiently overlapping filaments. RAD51 filaments can be formed at several different conditions, varying the cation (Mg(2+) or Ca(2+)), the DNA substrate (single-stranded or double-stranded), and the RAD51 concentration during filament nucleation, and we compare the properties of the different filaments formed. The results provide important information regarding the physical properties of RAD51 filaments but also demonstrate that nanofluidic channels are perfectly suited to study protein-DNA complexes.
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The REvolutionary Approaches and Devices for Nucleic Acid analysis (READNA) project received funding from the European Commission for 41/2 years. The objectives of the project revolved around technological developments in nucleic acid analysis. The project partners have discovered, created and developed a huge body of insights into nucleic acid analysis, ranging from improvements and implementation of current technologies to the most promising sequencing technologies that constitute a 3(rd) and 4(th) generation of sequencing methods with nanopores and in situ sequencing, respectively.
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Biotecnología/métodos , ADN/análisis , ADN/genética , Animales , Química Clic , Exoma/genética , Humanos , Espectrometría de Masas , Análisis de Secuencia de ADNRESUMEN
Biochemical and genetic data show that ribosomes closely follow RNA polymerases that are transcribing protein-coding genes in bacteria. At the same time, electron and fluorescence microscopy have revealed that ribosomes are excluded from the Escherichia coli nucleoid, which seems to be inconsistent with fast translation initiation on nascent mRNA transcripts. The apparent paradox can be reconciled if translation of nascent mRNAs can start throughout the nucleoid before they relocate to the periphery. However, this mechanism requires that free ribosomal subunits are not excluded from the nucleoid. Here, we use single-particle tracking in living E. coli cells to determine the fractions of free ribosomal subunits, classify individual subunits as free or mRNA-bound, and quantify the degree of exclusion of bound and free subunits separately. We show that free subunits are not excluded from the nucleoid. This finding strongly suggests that translation of nascent mRNAs can start throughout the nucleoid, which reconciles the spatial separation of DNA and ribosomes with cotranscriptional translation. We also show that, after translation inhibition, free subunit precursors are partially excluded from the compacted nucleoid. This finding indicates that it is active translation that normally allows ribosomal subunits to assemble on nascent mRNAs throughout the nucleoid and that the effects of translation inhibitors are enhanced by the limited access of ribosomal subunits to nascent mRNAs in the compacted nucleoid.
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Rastreo Celular/métodos , ADN Bacteriano/metabolismo , Escherichia coli/citología , Escherichia coli/metabolismo , Subunidades Ribosómicas/metabolismo , Eritromicina/farmacología , Escherichia coli/efectos de los fármacos , Proteínas de Escherichia coli/metabolismo , Viabilidad Microbiana/efectos de los fármacos , Microfluídica , Biosíntesis de Proteínas/efectos de los fármacos , ARN Mensajero/metabolismoRESUMEN
Salivary gland carcinomas (SGCs) are uncommon tumors, constituting approximately 5% of all cancers of the head and neck. They are a heterogeneous group of diseases that pose significant diagnostic and therapeutic challenges. The treatment of patients with SGCs is mainly restricted to surgery and/or radiation therapy and there is only limited data available on the role of conventional systemic and targeted therapies in the management of patients with advanced disease. There is thus a great need to develop new molecular biomarkers to improve the diagnosis, prognostication, and therapeutic options for these patients. In this review, we will discuss the most recent developments in this field, with focus on pathognomonic gene fusions and other driver mutations of clinical significance. Comprehensive cytogenetic and molecular genetic analyses of SGCs have revealed a translocation-generated network of fusion oncogenes. The molecular targets of these fusions are transcription factors, transcriptional coactivators, and tyrosine kinase receptors. Prominent examples of clinically significant fusions are the MYB-NFIB fusion in adenoid cystic carcinoma and the CRTC1-MAML2 fusion in mucoepidermoid carcinoma. The fusions are key events in the molecular pathogenesis of these tumor types and contribute as new diagnostic, prognostic, and therapeutic biomarkers. Moreover, next-generation sequencing analysis of SGCs have revealed new druggable driver mutations, pinpointing alternative therapeutic options for subsets of patients. Continued molecular characterization of these fusions and their down-stream targets will ultimately lead to the identification of novel driver genes in SGCs and will form the basis for development of new therapeutic strategies for these patients.
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Biomarcadores/metabolismo , Neoplasias de las Glándulas Salivales/metabolismo , Humanos , Neoplasias de las Glándulas Salivales/patologíaRESUMEN
Transcription factors mediate gene regulation by site-specific binding to chromosomal operators. It is commonly assumed that the level of repression is determined solely by the equilibrium binding of a repressor to its operator. However, this assumption has not been possible to test in living cells. Here we have developed a single-molecule chase assay to measure how long an individual transcription factor molecule remains bound at a specific chromosomal operator site. We find that the lac repressor dimer stays bound on average 5 min at the native lac operator in Escherichia coli and that a stronger operator results in a slower dissociation rate but a similar association rate. Our findings do not support the simple equilibrium model. The discrepancy with this model can, for example, be accounted for by considering that transcription initiation drives the system out of equilibrium. Such effects need to be considered when predicting gene activity from transcription factor binding strengths.
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Regulación de la Expresión Génica/fisiología , Modelos Genéticos , Factores de Transcripción/metabolismo , Escherichia coli , Regulación de la Expresión Génica/genética , Cinética , Represoras Lac/genética , Represoras Lac/metabolismo , Microfluídica , Microscopía Fluorescente , Regiones Operadoras Genéticas/genética , Unión Proteica , Factores de Tiempo , Factores de Transcripción/genéticaRESUMEN
A method to investigate physical properties of a DNA-protein complex in solution is demonstrated. By using tapered nanochannels and lipid passivation the persistence length of a RecA filament formed on double-stranded DNA is determined to 1.15 µm, in agreement with the literature, without attaching protein or DNA to any handles or surfaces.