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1.
Cell ; 154(6): 1232-45, 2013 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-24034247

RESUMEN

The histone variant H2A.Z is a genome-wide signature of nucleosomes proximal to eukaryotic regulatory DNA. Whereas the multisubunit chromatin remodeler SWR1 is known to catalyze ATP-dependent deposition of H2A.Z, the mechanism of SWR1 recruitment to S. cerevisiae promoters has been unclear. A sensitive assay for competitive binding of dinucleosome substrates revealed that SWR1 preferentially binds long nucleosome-free DNA and the adjoining nucleosome core particle, allowing discrimination of gene promoters over gene bodies. Analysis of mutants indicates that the conserved Swc2/YL1 subunit and the adenosine triphosphatase domain of Swr1 are mainly responsible for binding to substrate. SWR1 binding is enhanced on nucleosomes acetylated by the NuA4 histone acetyltransferase, but recognition of nucleosome-free and nucleosomal DNA is dominant over interaction with acetylated histones. Such hierarchical cooperation between DNA and histone signals expands the dynamic range of genetic switches, unifying classical gene regulation by DNA-binding factors with ATP-dependent nucleosome remodeling and posttranslational histone modifications.


Asunto(s)
Ensamble y Desensamble de Cromatina , Histonas/metabolismo , Complejos Multiproteicos/metabolismo , Nucleosomas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Acetilación , Adenosina Trifosfatasas/metabolismo , Secuencia de Bases , Histona Acetiltransferasas/metabolismo , Datos de Secuencia Molecular , Procesamiento Proteico-Postraduccional , Saccharomyces cerevisiae/genética
2.
Cell ; 143(5): 725-36, 2010 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-21111233

RESUMEN

Histone variant H2A.Z-containing nucleosomes are incorporated at most eukaryotic promoters. This incorporation is mediated by the conserved SWR1 complex, which replaces histone H2A in canonical nucleosomes with H2A.Z in an ATP-dependent manner. Here, we show that promoter-proximal nucleosomes are highly heterogeneous for H2A.Z in Saccharomyces cerevisiae, with substantial representation of nucleosomes containing one, two, or zero H2A.Z molecules. SWR1-catalyzed H2A.Z replacement in vitro occurs in a stepwise and unidirectional fashion, one H2A.Z-H2B dimer at a time, producing heterotypic nucleosomes as intermediates and homotypic H2A.Z nucleosomes as end products. The ATPase activity of SWR1 is specifically stimulated by H2A-containing nucleosomes without ensuing histone H2A eviction. Remarkably, further addition of free H2A.Z-H2B dimer leads to hyperstimulation of ATPase activity, eviction of nucleosomal H2A-H2B, and deposition of H2A.Z-H2B. These results suggest that the combination of H2A-containing nucleosome and free H2A.Z-H2B dimer acting as both effector and substrate for SWR1 governs the specificity and outcome of the replacement reaction.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Ensamble y Desensamble de Cromatina , Histonas/metabolismo , Nucleosomas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Dimerización , Histonas/química , Histonas/genética , Regiones Promotoras Genéticas , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética
3.
Mol Cell Proteomics ; 22(7): 100580, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37211046

RESUMEN

Current proteomic technologies focus on the quantification of protein levels, while little effort is dedicated to the development of system approaches to simultaneously monitor proteome variability and abundance. Protein variants may display different immunogenic epitopes detectable by monoclonal antibodies. Epitope variability results from alternative splicing, posttranslational modifications, processing, degradation, and complex formation and possesses dynamically changing availability of interacting surface structures that frequently serve as reachable epitopes and often carry different functions. Thus, it is highly likely that the presence of some of the accessible epitopes correlates with function under physiological and pathological conditions. To enable the exploration of the impact of protein variation on the immunogenic epitome first, here, we present a robust and analytically validated PEP technology for characterizing immunogenic epitopes of the plasma. To this end, we prepared mAb libraries directed against the normalized human plasma proteome as a complex natural immunogen. Antibody producing hybridomas were selected and cloned. Monoclonal antibodies react with single epitopes, thus profiling with the libraries is expected to profile many epitopes which we define by the mimotopes, as we present here. Screening blood plasma samples from control subjects (n = 558) and cancer patients (n = 598) for merely 69 native epitopes displayed by 20 abundant plasma proteins resulted in distinct cancer-specific epitope panels that showed high accuracy (AUC 0.826-0.966) and specificity for lung, breast, and colon cancer. Deeper profiling (≈290 epitopes of approximately 100 proteins) showed unexpected granularity of the epitope-level expression data and detected neutral and lung cancer-associated epitopes of individual proteins. Biomarker epitope panels selected from a pool of 21 epitopes of 12 proteins were validated in independent clinical cohorts. The results demonstrate the value of PEP as a rich and thus far unexplored source of protein biomarkers with diagnostic potential.


Asunto(s)
Biomarcadores de Tumor , Neoplasias , Humanos , Proteoma , Proteómica/métodos , Epítopos , Anticuerpos Monoclonales/química
4.
Genes Dev ; 31(19): 1958-1972, 2017 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29074736

RESUMEN

Histone CENP-A-containing nucleosomes play an important role in nucleating kinetochores at centromeres for chromosome segregation. However, the molecular mechanisms by which CENP-A nucleosomes engage with kinetochore proteins are not well understood. Here, we report the finding of a new function for the budding yeast Cse4/CENP-A histone-fold domain interacting with inner kinetochore protein Mif2/CENP-C. Strikingly, we also discovered that AT-rich centromere DNA has an important role for Mif2 recruitment. Mif2 contacts one side of the nucleosome dyad, engaging with both Cse4 residues and AT-rich nucleosomal DNA. Both interactions are directed by a contiguous DNA- and histone-binding domain (DHBD) harboring the conserved CENP-C motif, an AT hook, and RK clusters (clusters enriched for arginine-lysine residues). Human CENP-C has two related DHBDs that bind preferentially to DNA sequences of higher AT content. Our findings suggest that a DNA composition-based mechanism together with residues characteristic for the CENP-A histone variant contribute to the specification of centromere identity.


Asunto(s)
Proteína A Centromérica/metabolismo , Centrómero/metabolismo , Proteínas Cromosómicas no Histona/metabolismo , Modelos Moleculares , Nucleosomas/química , Nucleosomas/metabolismo , Saccharomyces cerevisiae , Secuencia Rica en At , Centrómero/química , Proteína A Centromérica/química , Proteínas Cromosómicas no Histona/química , ADN Satélite/metabolismo , Proteínas de Unión al ADN/metabolismo , Dimerización , Humanos , Unión Proteica , Estructura Terciaria de Proteína , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
5.
Proc Natl Acad Sci U S A ; 117(35): 21628-21636, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32817529

RESUMEN

Transcription is punctuated by RNA polymerase (RNAP) pausing. These pauses provide time for diverse regulatory events that can modulate gene expression. Transcription elongation factors dramatically affect RNAP pausing in vitro, but the genome-wide role of such factors on pausing has not been examined. Using native elongating transcript sequencing followed by RNase digestion (RNET-seq), we analyzed RNAP pausing in Bacillus subtilis genome-wide and identified an extensive role of NusG in pausing. This universally conserved transcription elongation factor is known as Spt5 in archaeal and eukaryotic organisms. B. subtilis NusG shifts RNAP to the posttranslocation register and induces pausing at 1,600 sites containing a consensus TTNTTT motif in the nontemplate DNA strand within the paused transcription bubble. The TTNTTT motif is necessary but not sufficient for NusG-dependent pausing. Approximately one-fourth of these pause sites were localized to untranslated regions and could participate in posttranscription initiation control of gene expression as was previously shown for tlrB and the trpEDCFBA operon. Most of the remaining pause sites were identified in protein-coding sequences. NusG-dependent pausing was confirmed for all 10 pause sites that we tested in vitro. Putative pause hairpins were identified for 225 of the 342 strongest NusG-dependent pause sites, and some of these hairpins were shown to function in vitro. NusG-dependent pausing in the ribD riboswitch provides time for cotranscriptional binding of flavin mononucleotide, which decreases the concentration required for termination upstream of the ribD coding sequence. Our phylogenetic analysis implicates NusG-dependent pausing as a widespread mechanism in bacteria.


Asunto(s)
Bacillus subtilis/genética , Proteínas de Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica/genética , Factores de Elongación de Péptidos/genética , Factores de Transcripción/genética , Proteínas Bacterianas/metabolismo , ARN Polimerasas Dirigidas por ADN/metabolismo , Proteínas de Escherichia coli/metabolismo , Conformación de Ácido Nucleico , Operón/genética , Factores de Elongación de Péptidos/metabolismo , Factores de Transcripción/metabolismo , Transcripción Genética/genética , Factores de Elongación Transcripcional/genética , Factores de Elongación Transcripcional/metabolismo , Translocación Genética/genética
6.
Am J Obstet Gynecol ; 226(2): 222.e1-222.e13, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34534506

RESUMEN

BACKGROUND: A number of retrospective and prospective studies have documented substantial rates of regression in cervical intraepithelial neoplasia grade 2 lesions in young women. Initial observational management of cervical intraepithelial neoplasia grade 2 is increasingly accepted as appropriate for women under 25 years of age with screen-detected abnormalities and is included in a number of clinical guidelines. However, there has been a paucity of large prospective studies on observational management with strict inclusion criteria. A number of important questions remain, specifically regarding the clinical variables that are associated with the risk of progression or persistence of disease. To investigate these factors and to ensure that young women with cervical intraepithelial neoplasia grade 2 undergoing observational management were being managed in a well-monitored and an appropriately informed fashion, we conducted a large, multicenter prospective study on observational management of cervical intraepithelial neoplasia grade 2 in women under 25 years. OBJECTIVE: This study aimed to determine the regression rates and clinical, cytologic, and pathologic predictors of regression of cervical intraepithelial neoplasia grade 2 in women under 25 years undergoing observational management over 24 months. STUDY DESIGN: This study was a multicenter prospective study on observational management of cervical intraepithelial neoplasia grade 2 (ie, repeat colposcopy, cytology, and cervical biopsy every 6 months) for up to 24 months. A total of 615 consenting women under 25 years with newly-diagnosed, biopsy-proven cervical intraepithelial neoplasia grade 2 were recruited (from 2010 to 2016) through 16 hospital-based colposcopy units in New Zealand and Australia. RESULTS: At completion, 326 women had confirmed regression, 156 had persistent high-grade cervical intraepithelial neoplasia grade 2 or 3 or adenocarcinoma in situ, and 24 had unconfirmed regression (ie, first regression at the 24-month follow-up). A total of 109 women did not complete the protocol (41 because of delayed follow-up, 41 lost to follow-up, 22 elected treatment, 4 refused a biopsy, and 1 died of an unrelated cause). Confirmed regression was observed in 53% (326 of 615) of all women enrolled in the study and, when missing data were imputed, it was estimated that 64% of women (95% confidence interval, 60%-68%) would have experienced regression. Similarly, lesions regressed in 64% (326 of 506) of women who completed the observational protocol. Based on a multivariable analysis, detection of human papillomavirus 16 in a liquid-based cytology sample at the time of initial colposcopy decreased the chance of regression by 31% (risk ratio, 0.69; 95% confidence interval, 0.56-0.86; P<.001). In addition, at initial colposcopy, low-grade or normal colposcopic impression, later year of diagnosis, low-grade or normal cytology, and being a nonsmoker were all independently associated with an increased chance of regression. CONCLUSION: More than half of women under 25 years with cervical intraepithelial neoplasia grade 2 will regress to cervical intraepithelial neoplasia grade 1 or normal within 24 months without destructive treatment. The absence of human papillomavirus 16 is the most important predictor of regression.


Asunto(s)
Regresión Neoplásica Espontánea/patología , Displasia del Cuello del Útero/patología , Neoplasias del Cuello Uterino/patología , Adolescente , Australia , Femenino , Humanos , Clasificación del Tumor , Nueva Zelanda , Infecciones por Papillomavirus/patología , Adulto Joven
7.
BMC Nephrol ; 22(1): 406, 2021 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-34876054

RESUMEN

BACKGROUND: Increased perioperative pro-inflammatory biomarkers, renal hypoperfusion and ischemia reperfusion injury (IRI) heighten cardiac surgery acute kidney injury (CS-AKI) risk. Increased urinary anti-inflammatory cytokines attenuate risk. We evaluated whether blood and urinary anti-inflammatory biomarkers, when expressed as ratios with biomarkers of inflammation, hypoperfusion and IRI are increased in CS-AKI patients. METHODS: Preoperative and 24-h postoperative blood and urinary pro-inflammatory and anti-inflammatory cytokines, blood VEGF and H-FABP (hypoperfusion biomarkers), and MK, a biomarker for IRI, were measured in 401 cardiac surgery patients. Pre- and postoperative concentrations of biomarkers and selected ratios thereof, were compared between non-CS-AKI and CS-AKI patients. RESULTS: Compared with non-CS-AKI, blood pro-inflammatory (pre- and post-op TNFα, IP-10, IL-12p40, MIP-1α, NGAL; pre-op IL-6; post-op IL-8, MK) and anti-inflammatory (pre- and post-op sTNFsr1, sTNFsr2, IL-1RA) biomarkers together with urinary pro-inflammatory (pre- and post-op uIL-12p40; post-op uIP-10, uNGAL) and anti-inflammatory (pre- and post-op usTNFsr1, usTNFsr2, uIL-1RA) biomarkers, were significantly higher in CS-AKI patients. Urinary anti-inflammatory biomarkers, when expressed as ratios with biomarkers of inflammation (blood and urine), hypoperfusion (blood H-FABP and VEGF) and IRI (blood MK) were decreased in CS-AKI. In contrast, blood anti-inflammatory biomarkers expressed as similar ratios with blood biomarkers were increased in CS-AKI. CONCLUSIONS: The urinary anti-inflammatory response may protect against the injurious effects of perioperative inflammation, hypoperfusion and IRI. These finding may have clinical utility in bioprediction and earlier diagnosis of CS-AKI and informing future therapeutic strategies for CS-AKI patients.


Asunto(s)
Lesión Renal Aguda/sangre , Lesión Renal Aguda/orina , Procedimientos Quirúrgicos Cardíacos , Citocinas/sangre , Citocinas/orina , Complicaciones Posoperatorias/sangre , Complicaciones Posoperatorias/orina , Anciano , Biomarcadores/sangre , Biomarcadores/orina , Femenino , Humanos , Masculino , Persona de Mediana Edad
8.
Am J Obstet Gynecol ; 223(3): 408.e1-408.e11, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32109465

RESUMEN

BACKGROUND: A high rate of regression in young women with cervical intraepithelial neoplasia grade 2 has been recorded. However, there are few prospective data by which to evaluate management guidelines. OBJECTIVE: This study evaluates the American Society for Colposcopy and Cervical Pathology recommendations for follow-up of young women with cervical intraepithelial neoplasia 2 using data created by a large prospective multicenter study of observational management. MATERIALS AND METHODS: Participants were 616 women under 25 years with biopsy-diagnosed cervical intraepithelial neoplasia 2 following a referral to colposcopy for an abnormal smear with no previous high-grade abnormality. The protocol included colposcopy, cytology, and colposcopically directed biopsy at the initial visit and at 6- and 12-month follow-ups visits, and these data were analyzed. Histology from the corresponding cervical biopsy was treated as the reference diagnostic test. For young women with cervical intraepithelial neoplasia 2, we aimed to determine the following: (1) the ability of colposcopy to identify women with cervical intraepithelial neoplasia 3 or worse at 6 months; and (2) the ability of colposcopy, cytology, and a combination of cytology and colposcopy to identify residual high-grade abnormalities at 12 months. In addition, although not specified in the guidelines, we investigated the ability of high-risk human papillomavirus positivity alone or with cytology as a co-test to identify residual high-grade abnormalities at 12 months. RESULTS: At 6 months, cervical intraepithelial neoplasia 3+ colposcopic appearance identified only 28% (95% confidence interval, 18-40%) of women diagnosed with cervical intraepithelial neoplasia 3. At 12 months, a high-grade colposcopic appearance identified only 58% (95% confidence interval, 48-68%) of women with residual histological cervical intraepithelial neoplasia 2 or 3. At 12 months, high-grade cytology identified only 58% (95% confidence interval, 48-68%) of women with cervical intraepithelial neoplasia 2 or 3. However, the combination of either high-grade cytology or colposcopic appearance proved substantially more sensitive (81%; 95% confidence interval, 72-88%). High-risk human papillomavirus positivity at 12 months was a sensitive (96%; 95% confidence interval, 89-99%) indicator of persisting high-grade histology. However, this sensitivity came at the expense of specificity (52%; 95% confidence interval, 45-58%). A co-test of high-risk human papillomavirus positivity or high-grade cytology at 12 months provided a high sensitivity (97%; 95% confidence interval, 90-99%) but low specificity (51%; 95% confidence interval, 45%-58%). CONCLUSION: Colposcopy and cytology are limited in their ability to exclude persistent high-grade abnormality for young women undergoing observational management for cervical intraepithelial neoplasia 2. We recommend biopsy for all women at 12 months. High-risk human papillomavirus positivity is a sensitive indicator of persistent abnormality and should be considered in those not having a biopsy.


Asunto(s)
Colposcopía/normas , Recurrencia Local de Neoplasia/prevención & control , Guías de Práctica Clínica como Asunto , Pautas de la Práctica en Medicina/normas , Displasia del Cuello del Útero/prevención & control , Neoplasias del Cuello Uterino/prevención & control , Adolescente , Femenino , Humanos , Clasificación del Tumor , Recurrencia Local de Neoplasia/patología , Estudios Prospectivos , Sociedades Médicas , Estados Unidos , Neoplasias del Cuello Uterino/patología , Adulto Joven , Displasia del Cuello del Útero/patología
9.
Nature ; 516(7531): 432-435, 2014 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-25307058

RESUMEN

Eukaryotic genomes are folded into three-dimensional structures, such as self-associating topological domains, the borders of which are enriched in cohesin and CCCTC-binding factor (CTCF) required for long-range interactions. How local chromatin interactions govern higher-order folding of chromatin fibres and the function of cohesin in this process remain poorly understood. Here we perform genome-wide chromatin conformation capture (Hi-C) analysis to explore the high-resolution organization of the Schizosaccharomyces pombe genome, which despite its small size exhibits fundamental features found in other eukaryotes. Our analyses of wild-type and mutant strains reveal key elements of chromosome architecture and genome organization. On chromosome arms, small regions of chromatin locally interact to form 'globules'. This feature requires a function of cohesin distinct from its role in sister chromatid cohesion. Cohesin is enriched at globule boundaries and its loss causes disruption of local globule structures and global chromosome territories. By contrast, heterochromatin, which loads cohesin at specific sites including pericentromeric and subtelomeric domains, is dispensable for globule formation but nevertheless affects genome organization. We show that heterochromatin mediates chromatin fibre compaction at centromeres and promotes prominent inter-arm interactions within centromere-proximal regions, providing structural constraints crucial for proper genome organization. Loss of heterochromatin relaxes constraints on chromosomes, causing an increase in intra- and inter-chromosomal interactions. Together, our analyses uncover fundamental genome folding principles that drive higher-order chromosome organization crucial for coordinating nuclear functions.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Proteínas Cromosómicas no Histona/metabolismo , Genoma Fúngico , Heterocromatina/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Schizosaccharomyces/fisiología , Conformación Molecular , Schizosaccharomyces/genética , Cohesinas
10.
Nutr Metab Cardiovasc Dis ; 30(7): 1169-1178, 2020 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-32448720

RESUMEN

BACKGROUND AND AIMS: This study aimed to assess possible association of detailed abdominal fat profiles with coronary plaque characteristics in patients with acute coronary syndrome (ACS). METHODS AND RESULTS: In 60 patients with ACS, culprit arteries were evaluated at 1-mm intervals (length analyzed: 66 ± 28 mm) by grayscale and integrated backscatter intravascular ultrasound (IB-IVUS) before percutaneous coronary intervention. Standard IVUS indexes (as a volume index: volume/length), plaque components (as percent tissue volume) and fibrous cap thickness (FCT) were assessed by IB-IVUS. Plain abdominal computed tomography was performed to evaluate subcutaneous adipose tissue (SAT) area, visceral adipose tissue (VAT) area, and VAT/SAT ratio. While SAT area only correlated with vessel volume (r = 0.27, p = 0.04), VAT area correlated positively with vessel (r = 0.30, p = 0.02) and plaque (r = 0.33, p = 0.01) volumes and negatively with FCT (r = -0.26, p = 0.049), but not with percent plaque volume and plaque tissue components. In contrast, higher VAT/SAT ratio significantly correlated with higher percent lipid (r = 0.34, p = 0.008) and lower percent fibrous (r = -0.34, p = 0.007) volumes with a trend toward larger percent plaque volume (r = 0.19, p = 0.15), as well as thinner FCT (r = -0.53, p < 0.0001). In the multiple regression analysis, higher VAT/SAT ratio was independently associated with higher percent lipid with lower percent fibrous volumes (p = 0.03 for both) and thinner fibrous cap thickness (p = 0.0001). CONCLUSION: Coronary plaque vulnerability, defined as increased lipid content with thinner fibrous cap thickness, appears to be more related to abnormal abdominal fat distribution, or so-called hidden obesity, compared with visceral or subcutaneous fat amount alone in patients with ACS.


Asunto(s)
Grasa Abdominal/diagnóstico por imagen , Síndrome Coronario Agudo/diagnóstico por imagen , Adiposidad , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Vasos Coronarios/diagnóstico por imagen , Placa Aterosclerótica , Tomografía Computarizada por Rayos X , Ultrasonografía Intervencional , Grasa Abdominal/fisiopatología , Síndrome Coronario Agudo/fisiopatología , Anciano , Enfermedad de la Arteria Coronaria/fisiopatología , Femenino , Fibrosis , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Rotura Espontánea
11.
Proc Natl Acad Sci U S A ; 114(21): 5479-5484, 2017 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-28490498

RESUMEN

The dynamic nature of genome organization impacts critical nuclear functions including the regulation of gene expression, replication, and DNA damage repair. Despite significant progress, the mechanisms responsible for reorganization of the genome in response to cellular stress, such as aberrant DNA replication, are poorly understood. Here, we show that fission yeast cells carrying a mutation in the DNA-binding protein Sap1 show defects in DNA replication progression and genome stability and display extensive changes in genome organization. Chromosomal regions such as subtelomeres that show defects in replication progression associate with the nuclear envelope in sap1 mutant cells. Moreover, high-resolution, genome-wide chromosome conformation capture (Hi-C) analysis revealed prominent contacts between telomeres and chromosomal arm regions containing replication origins proximal to binding sites for Taz1, a component of the Shelterin telomere protection complex. Strikingly, we find that Shelterin components are required for interactions between Taz1-associated chromosomal arm regions and telomeres. These analyses reveal an unexpected role for Shelterin components in genome reorganization in cells experiencing replication stress, with important implications for understanding the mechanisms governing replication and genome stability.


Asunto(s)
Daño del ADN , Replicación del ADN , Proteínas de Unión al ADN/fisiología , Genoma Fúngico , Inestabilidad Genómica , Proteínas de Schizosaccharomyces pombe/fisiología , ADN de Cadena Simple/metabolismo , Reordenamiento Génico , Mutación , Origen de Réplica , Schizosaccharomyces
12.
Aust N Z J Obstet Gynaecol ; 60(3): 444-448, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32080827

RESUMEN

BACKGROUND: Cervical screening programs have had an important effect on the reduction of cervical cancer rates. Comprehensive programs require access to pathological review to improve the sensitivity of screening cytology and the specificity of diagnostic histology. AIMS: To determine the number of cases where cervical cytology or histology was amended at cytopathological review; whether amendments were 'upgrades' or 'downgrades', and how amendments aligned with follow-up results for these patients. MATERIALS AND METHODS: A retrospective cohort study was performed of all patients reviewed from January 2016 to December 2017 (n = 287 cases, from 254 patients) at colposcopy multidisciplinary meetings at Wellington Hospital, a tertiary referral hospital. Where amendments to cytology or histology were made, follow-up results were retrieved where available (85.7% and 84.2% respectively). RESULTS: Cytology or histology was amended in 24.7% of cases. Smear cytology was amended in 16.7%. Where cytology was upgraded (n = 9), 44% had subsequent results of equal or higher grade including one case of adenocarcinoma. Where cytology was downgraded (n = 19), 93.8% (81.9-100%) had follow-up studies showing equal or lower results. Cervical biopsy histology was amended in 12.2% of cases (upgraded n = 19, downgraded n = 6). Large loop excision of the transformation zone or cone biopsy histology was amended in three cases (7.9%). CONCLUSIONS: Cytopathological review appears to improve the specificity of the comprehensive cervical screening program, leading to a reduction in unnecessary treatment. Additionally, a small number of cases of malignant or premalignant disease were detected.


Asunto(s)
Cuello del Útero/patología , Displasia del Cuello del Útero/diagnóstico , Neoplasias del Cuello Uterino/diagnóstico , Colposcopía , Detección Precoz del Cáncer , Femenino , Estudios de Seguimiento , Humanos , Tamizaje Masivo , Grupo de Atención al Paciente , Estudios Retrospectivos , Sensibilidad y Especificidad , Neoplasias del Cuello Uterino/patología , Frotis Vaginal , Displasia del Cuello del Útero/patología
13.
Mol Ther ; 26(2): 379-389, 2018 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-29174843

RESUMEN

The adoptive transfer of neoantigen-reactive tumor-infiltrating lymphocytes (TILs) can result in tumor regression in patients with metastatic cancer. To improve the efficacy of adoptive T cell therapy targeting these tumor-specific mutations, we have proposed a new therapeutic strategy, which involves the genetic modification of autologous T cells with neoantigen-specific T cell receptors (TCRs) and the transfer of these modified T cells back to cancer patients. However, the current techniques to isolate neoantigen-specific TCRs are labor intensive, time consuming, and technically challenging, not suitable for clinical applications. To facilitate this process, a new approach was developed, which included the co-culture of TILs with tandem minigene (TMG)-transfected or peptide-pulsed autologous antigen-presenting cells (APCs) and the single-cell RNA sequencing (RNA-seq) analysis of T cells to identify paired TCR sequences associated with cells expressing high levels of interferon-γ (IFN-γ) and interleukin-2 (IL-2). Following this new approach, multiple TCRs were identified, synthesized, cloned into a retroviral vector, and then transduced into donor T cells. These transduced T cells were shown to specifically recognize the neoantigens presented by autologous APCs. In conclusion, this approach provides an efficient procedure to isolate neoantigen-specific TCRs for clinical applications, as well as for basic and translational research.


Asunto(s)
Antígenos de Neoplasias/inmunología , Secuenciación de Nucleótidos de Alto Rendimiento , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/metabolismo , Análisis de la Célula Individual , Linfocitos T/inmunología , Linfocitos T/metabolismo , Línea Celular Tumoral , Humanos , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/metabolismo , Mutación , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/inmunología , Especificidad del Receptor de Antígeno de Linfocitos T/genética , Especificidad del Receptor de Antígeno de Linfocitos T/inmunología
14.
Heart Vessels ; 34(6): 926-935, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30535756

RESUMEN

Anatomical measurements obtained by intracoronary imaging devices are reported to correlate significantly with fractional flow reserve (FFR). Instantaneous wave-free ratio (iFR) is a nonhyperemic index of stenosis severity with discordant reports regarding its accuracy in relation to FFR. There is no information on the correlation of iFR with measurements derived from intracoronary imaging devices. The purpose of this study was to assess the relationship among iFR, intravascular ultrasound (IVUS), and optical frequency domain imaging (OFDI) parameters. Eighty lesions in 72 patients who underwent elective angiography and had intermediate lesions were enrolled. All lesions were assessed by iFR, FFR, IVUS, and OFDI. iFR was ≤ 0.89 in 21 (26%) lesions and FFR was ≤ 0.80 in 41 (51%) lesions. iFR correlated significantly with both IVUS-derived minimum lumen area (MLA) (r = 0.375, p = 0.003) and OFDI-derived MLA (r = 0.357, p = 0.005). FFR also correlated significantly with both IVUS-derived MLA (r = 0.472, p < 0.001) and OFDI-derived MLA (r = 0.445, p < 0.001). Among the lesions with FFR ≤ 0.80, iFR > 0.89 (mismatch) was observed in 20 lesions. There was no lesion with iFR ≤ 0.89 (reverse mismatch) among the lesions with FFR > 0.80. The lesion location among three major coronary vessels was related with the discrepancy between iFR and FFR (p = 0.007). In conclusion, iFR and FFR showed a significant correlation with IVUS and OFDI measurements. The discrepancy of iFR and FFR was associated with the lesion locations.


Asunto(s)
Cateterismo Cardíaco/instrumentación , Estenosis Coronaria/diagnóstico por imagen , Vasos Coronarios/diagnóstico por imagen , Reserva del Flujo Fraccional Miocárdico , Anciano , Angiografía Coronaria/métodos , Estenosis Coronaria/fisiopatología , Vasos Coronarios/fisiopatología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Modelos Lineales , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Curva ROC , Tomografía de Coherencia Óptica/métodos , Ultrasonografía Intervencional/métodos
15.
PLoS Genet ; 12(2): e1005874, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26910538

RESUMEN

Vascular endothelial growth factor (VEGF) is an angiogenic and neurotrophic factor, secreted by endothelial cells, known to impact various physiological and disease processes from cancer to cardiovascular disease and to be pharmacologically modifiable. We sought to identify novel loci associated with circulating VEGF levels through a genome-wide association meta-analysis combining data from European-ancestry individuals and using a dense variant map from 1000 genomes imputation panel. Six discovery cohorts including 13,312 samples were analyzed, followed by in-silico and de-novo replication studies including an additional 2,800 individuals. A total of 10 genome-wide significant variants were identified at 7 loci. Four were novel loci (5q14.3, 10q21.3, 16q24.2 and 18q22.3) and the leading variants at these loci were rs114694170 (MEF2C, P = 6.79 x 10(-13)), rs74506613 (JMJD1C, P = 1.17 x 10(-19)), rs4782371 (ZFPM1, P = 1.59 x 10(-9)) and rs2639990 (ZADH2, P = 1.72 x 10(-8)), respectively. We also identified two new independent variants (rs34528081, VEGFA, P = 1.52 x 10(-18); rs7043199, VLDLR-AS1, P = 5.12 x 10(-14)) at the 3 previously identified loci and strengthened the evidence for the four previously identified SNPs (rs6921438, LOC100132354, P = 7.39 x 10(-1467); rs1740073, C6orf223, P = 2.34 x 10(-17); rs6993770, ZFPM2, P = 2.44 x 10(-60); rs2375981, KCNV2, P = 1.48 x 10(-100)). These variants collectively explained up to 52% of the VEGF phenotypic variance. We explored biological links between genes in the associated loci using Ingenuity Pathway Analysis that emphasized their roles in embryonic development and function. Gene set enrichment analysis identified the ERK5 pathway as enriched in genes containing VEGF associated variants. eQTL analysis showed, in three of the identified regions, variants acting as both cis and trans eQTLs for multiple genes. Most of these genes, as well as some of those in the associated loci, were involved in platelet biogenesis and functionality, suggesting the importance of this process in regulation of VEGF levels. This work also provided new insights into the involvement of genes implicated in various angiogenesis related pathologies in determining circulating VEGF levels. The understanding of the molecular mechanisms by which the identified genes affect circulating VEGF levels could be important in the development of novel VEGF-related therapies for such diseases.


Asunto(s)
Sitios Genéticos , Factor A de Crecimiento Endotelial Vascular/sangre , Factor A de Crecimiento Endotelial Vascular/genética , Cromosomas Humanos , Expresión Génica , Estudio de Asociación del Genoma Completo , Humanos , Polimorfismo de Nucleótido Simple , Factor A de Crecimiento Endotelial Vascular/metabolismo , Población Blanca/genética
16.
Int J Mol Sci ; 20(5)2019 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-30813608

RESUMEN

Epigenome-Wide Association Studies (EWAS) are furthering our knowledge of epigenetic modifications involved in the regulation of lipids' metabolism. Furthermore, epigenetic patterns associated with lipid levels may play an important role in predicting the occurrence of cardiovascular events. To further investigate the relationship between methylation status and lipids, we performed an EWAS in 211 individuals from the STANISLAS Family study (SFS). Methylation at two CpG sites (PRKAG2; p = 1.39 × 10-8; KREMEN2; p = 5.75 × 10-9) were significantly associated with lipidomic profiles. Replication was sought in adipose tissue where one probe, cg08897188, was found to be nominally significant (KREMEN2; p = 0.0196). These results could provide new insight in the mechanisms underlying cardiovascular diseases and contribute to new therapeutic interventions.


Asunto(s)
Epigénesis Genética , Estudio de Asociación del Genoma Completo , Lípidos/sangre , Tejido Adiposo/metabolismo , Biología Computacional , Islas de CpG/genética , Metilación de ADN/genética , Familia , Variación Genética , Humanos , Regiones Promotoras Genéticas/genética , Reproducibilidad de los Resultados
17.
Transfusion ; 58 Suppl 3: 3065-3071, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30536437

RESUMEN

BACKGROUND: To ensure that immunoglobulin (Ig) products have adequate functional antibody, the US Food and Drug Administration (FDA) requires that Ig lots contain minimum levels of measles neutralizing antibody; the current minimum is 0.48 x US Reference Ig 176. STUDY DESIGN AND METHODS: In the first part of the study, measles antibody titers were measured in donor plasma samples collected in 2007, 2011, and 2017. In the second part, trough or steady-state serum levels of measles neutralizing antibody were measured in two studies of patients with primary immunodeficiency (PID) who were treated with intravenous (Study 1; N = 46) or subcutaneous (Study 2; N = 18) Ig replacement therapy, meeting previous requirements for lot potency (≥0.6 x US Reference Ig 176). Serum measles neutralizing antibody titers were then estimated for conditions in which the potency of the Ig replacement product was 0.48 or 0.30 x US Reference Ig 176. RESULTS: Measles antibody titers in donated plasma samples declined in donors born after 1963. In the two studies of patients with PID who were treated with intravenous or subcutaneous Ig replacement therapy, all patients exhibited trough (intravenous Ig) or steady-state (subcutaneous Ig) measles neutralizing antibody titers above 0.12 IU/mL, which has been shown to protect against clinical measles in the general population. Estimates suggest that all patients except one would have continued to meet this standard if the Ig lot potency had been 0.48 or 0.30 x US Reference Ig 176. CONCLUSION: These studies provide supporting evidence that the lot release specification can be safely lowered from 0.48 to 0.30 x US Reference Ig 176, which will accommodate declining measles neutralizing antibody levels in donor plasma.


Asunto(s)
Anticuerpos Antivirales/sangre , Donantes de Sangre , Inmunoglobulinas/administración & dosificación , Síndromes de Inmunodeficiencia/terapia , Vacuna Antisarampión , Sarampión/prevención & control , Adolescente , Adulto , Anciano , Anticuerpos Neutralizantes/análisis , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/administración & dosificación , Anticuerpos Antivirales/análisis , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunoglobulinas/sangre , Inmunoglobulinas Intravenosas/administración & dosificación , Inmunoglobulinas Intravenosas/sangre , Síndromes de Inmunodeficiencia/inmunología , Estudios Longitudinales , Masculino , Sarampión/inmunología , Vacuna Antisarampión/administración & dosificación , Vacuna Antisarampión/sangre , Vacuna Antisarampión/inmunología , Persona de Mediana Edad , Pruebas Serológicas , Volumetría , Vacunación , Potencia de la Vacuna , Adulto Joven
18.
Catheter Cardiovasc Interv ; 91(5): 874-883, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-28707349

RESUMEN

BACKGROUND: In vivo assessment of bioresorbable scaffold (BRS) is of growing clinical interest. The novel 60MHz high-definition intravascular ultrasound (HD-IVUS) has been developed to overcome the limitations of conventional 40 MHz IVUS. This study aimed to evaluate the performance and limitations of 60 MHz HD-IVUS compared with 40 MHz IVUS with respect to polymeric-strut visualization, quantitative and qualitative analysis, and feasibility of high-speed pullback in the assessment of BRS. METHODS AND RESULTS: In a bench-test model, 361 struts were analyzed to evaluate the influence of ultrasound-beam angles and proximity of adjacent struts on IVUS visualization of BRS struts. Various settings were created by deforming the BRS and positioning the transducer offcenter. In an in vivo swine coronary model, scaffold and lumen areas, degree of visible external elastic membrane, incomplete strut apposition, and strut fracture were evaluated in 59 matched cross-sections obtained at conventional (0.5 mm/sec) and high speed (10 mm/sec) pullbacks. Both studies utilized optical coherence tomography (OCT) as reference. Overall, 60 MHz HD-IVUS demonstrated significantly improved visualization of polymeric struts compared with 40 MHz IVUS (well-visualized: 84.5% vs 62.3%, not visible: 4.4% vs 13.9%, respectively. P < 0.001), which was less affected by the beam angle and adjacent strut proximity. In the in vivo model, 60-MHz HD-IVUS showed better agreement of area measurements and strut abnormalities with OCT than 40 MHz IVUS. These findings were also confirmed on high-speed pullback images of 60 MHz HD-IVUS. CONCLUSION: As referenced to OCT, this study showed superiority of 60 MHz HD-IVUS over 40 MHz IVUS in the assessment of BRS with feasibility of high-speed pullback imaging.


Asunto(s)
Implantes Absorbibles , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/cirugía , Intervención Coronaria Percutánea/instrumentación , Tomografía de Coherencia Óptica , Ultrasonografía Intervencional , Animales , Estudios de Factibilidad , Femenino , Ensayo de Materiales , Modelos Anatómicos , Modelos Animales , Valor Predictivo de las Pruebas , Diseño de Prótesis , Sus scrofa
19.
J Infect Dis ; 216(8): 977-980, 2017 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-28968738

RESUMEN

We report a screen of plasma donors confirming that widespread use of childhood measles vaccination since 1963 resulted in a decrease in average measles virus antibody titers among plasma donors, which is reflected in intravenous immunoglobulins (IVIGs). The measles virus antibody titer, however, is a potency requirement for IVIGs, as defined in a Food and Drug Administration regulation. To mitigate the decline in measles virus antibody titers in IVIGs and to ensure consistent product release, revaccination of plasma donors was investigated as a means to boost titers. However, revaccination-induced titer increases were only about 2-fold and short-lived.


Asunto(s)
Anticuerpos Antivirales/sangre , Donantes de Sangre , Inmunoglobulinas Intravenosas/administración & dosificación , Vacuna Antisarampión/inmunología , Virus del Sarampión/inmunología , Sarampión/prevención & control , Vacunación , Anticuerpos Neutralizantes , Humanos , Inmunización Secundaria , Masculino , Sarampión/inmunología , Sarampión/virología , Vacuna Antisarampión/administración & dosificación
20.
Genome Res ; 24(7): 1209-23, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24985915

RESUMEN

Accurate gene model annotation of reference genomes is critical for making them useful. The modENCODE project has improved the D. melanogaster genome annotation by using deep and diverse high-throughput data. Since transcriptional activity that has been evolutionarily conserved is likely to have an advantageous function, we have performed large-scale interspecific comparisons to increase confidence in predicted annotations. To support comparative genomics, we filled in divergence gaps in the Drosophila phylogeny by generating draft genomes for eight new species. For comparative transcriptome analysis, we generated mRNA expression profiles on 81 samples from multiple tissues and developmental stages of 15 Drosophila species, and we performed cap analysis of gene expression in D. melanogaster and D. pseudoobscura. We also describe conservation of four distinct core promoter structures composed of combinations of elements at three positions. Overall, each type of genomic feature shows a characteristic divergence rate relative to neutral models, highlighting the value of multispecies alignment in annotating a target genome that should prove useful in the annotation of other high priority genomes, especially human and other mammalian genomes that are rich in noncoding sequences. We report that the vast majority of elements in the annotation are evolutionarily conserved, indicating that the annotation will be an important springboard for functional genetic testing by the Drosophila community.


Asunto(s)
Biología Computacional/métodos , Drosophila melanogaster/genética , Perfilación de la Expresión Génica , Anotación de Secuencia Molecular , Transcriptoma , Animales , Análisis por Conglomerados , Drosophila melanogaster/clasificación , Evolución Molecular , Exones , Femenino , Genoma de los Insectos , Humanos , Masculino , Motivos de Nucleótidos , Filogenia , Posición Específica de Matrices de Puntuación , Regiones Promotoras Genéticas , Edición de ARN , Sitios de Empalme de ARN , Empalme del ARN , Reproducibilidad de los Resultados , Sitio de Iniciación de la Transcripción
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