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1.
EMBO J ; 41(8): e110070, 2022 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-35285528

RESUMEN

Transposable elements (TEs) constitute a major threat to genome stability and are therefore typically silenced by epigenetic mechanisms. In response, some TEs have evolved counteracting systems to suppress epigenetic silencing. In the model plant Arabidopsis thaliana, two such anti-silencing systems have been identified and found to be mediated by the VANC DNA-binding proteins encoded by VANDAL transposons. Here, we show that anti-silencing systems have rapidly diversified since their origin in eudicots by gaining and losing VANC-containing domains, such as DUF1985, DUF287, and Ulp1, as well as target sequence motifs. We further demonstrate that these motifs determine anti-silencing specificity by sequence, density, and helical periodicity. Moreover, such rapid diversification yielded at least 10 distinct VANC-induced anti-silencing systems in Arabidopsis. Strikingly, anti-silencing of non-autonomous VANDALs, which can act as reservoirs of 24-nt small RNAs, is critical to prevent the demise of cognate autonomous TEs and to ensure their propagation. Our findings illustrate how complex co-evolutionary dynamics between TEs and host suppression pathways have shaped the emergence of new epigenetic control mechanisms.


Asunto(s)
Arabidopsis , Elementos Transponibles de ADN , Arabidopsis/genética , Arabidopsis/metabolismo , Metilación de ADN , Elementos Transponibles de ADN/genética , Epigénesis Genética , Regulación de la Expresión Génica de las Plantas , Silenciador del Gen , Genoma de Planta , ARN Interferente Pequeño/genética
2.
EMBO Rep ; 24(8): e56678, 2023 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-37272687

RESUMEN

Transposable elements (TEs) are among the most dynamic parts of genomes. Since TEs are potentially deleterious, eukaryotes silence them through epigenetic mechanisms such as repressive histone modifications and DNA methylation. We previously reported that Arabidopsis TEs, called VANDALs, counteract epigenetic silencing through a group of sequence-specific anti-silencing proteins, VANCs. VANC proteins bind to noncoding regions of specific VANDAL copies and induce loss of silent chromatin marks. The VANC-target regions form tandem repeats, which diverge rapidly. Sequence-specific anti-silencing allows these TEs to proliferate with minimum host damage. Here, we show that RNA-directed DNA methylation (RdDM) efficiently targets noncoding regions of VANDAL TEs to silence them de novo. Thus, escape from RdDM could be a primary event leading to the rapid evolution and diversification of sequence-specific anti-silencing systems. We propose that this selfish behavior of TEs paradoxically could make them diverse and less harmful to the host.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Elementos Transponibles de ADN/genética , Silenciador del Gen , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Metilación de ADN , Epigénesis Genética , Arabidopsis/genética , Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas
3.
Diabetes Obes Metab ; 26(7): 2761-2773, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38646845

RESUMEN

AIMS: To evaluate the correlation between C-peptide index (CPI) at 2 h post-meal and endogenous insulin secretory capacity and to develop clinical models to predict the possibility of withdrawal from insulin therapy in patients with type 2 diabetes. METHOD: This was a single-centre retrospective study of patients with type 2 diabetes admitted to our hospital. Patients were divided into a withdrawal group (n = 72) and a non-withdrawal group (n = 75) based on whether they were able to withdraw from insulin therapy at discharge, and the correlation between CPI at 2 h after meal and diabetes-related parameters was evaluated. In addition, we created two clinical models to predict the possibility of withdrawal from insulin therapy using machine learning. RESULTS: The glycated haemoglobin values of the study participants were 87.8 ± 22.6 mmol/mo. The CPI at 2 h post-meal was 1.93 ± 1.28 in the non-withdrawal group and 2.97 ± 2.07 in the withdrawal group (p < 0.001). CPI at 2 h post-meal was an independent predictor of withdrawal from insulin therapy. In addition, CPI at 2 h post-meal was a better predictor than fasting CPI. Six factors associated with insulin therapy withdrawal (age, duration of diabetes, creatinine, alanine aminotransferase, insulin therapy until hospitalization, and CPI at 2 h post-meal) were used to generate two clinical models by machine learning. The accuracy of the generated clinical models ranged from 78.3% to 82.6%. CONCLUSION: The CPI at 2 h post-meal is a clinically useful measure of endogenous insulin secretory capacity under non-fasting conditions.


Asunto(s)
Péptido C , Diabetes Mellitus Tipo 2 , Hipoglucemiantes , Secreción de Insulina , Insulina , Periodo Posprandial , Humanos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/sangre , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Péptido C/sangre , Insulina/uso terapéutico , Insulina/administración & dosificación , Anciano , Hipoglucemiantes/uso terapéutico , Hemoglobina Glucada/análisis , Hemoglobina Glucada/metabolismo , Privación de Tratamiento/estadística & datos numéricos , Aprendizaje Automático , Comidas
4.
Endocr J ; 71(5): 481-488, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38447977

RESUMEN

Acute necrotizing esophagitis (ANE) is a rare and potentially life-threatening complication of diabetic ketoacidosis (DKA). While its association with DKA is established, specific clinical characteristics that predict ANE in DKA patients remain less understood. This study aimed to identify these characteristics by analyzing data from 30 DKA patients admitted from January 2018 to September 2022. Seven patients in this study presented with ANE, forming the ANE group. The remaining 23 constituted the non-ANE group. We compared the clinical parameters and computed tomography (CT) between the groups. The mean age of participants was 57.7 ± 20.4 years, and their mean HbA1c was 11.1 ± 3.3%. Notably, ethanol intake was significantly higher in the ANE group (44.4 ± 25.4 g/day) compared to the non-ANE group (6.8 ± 14.0 g/day; p = 0.013). Additionally, sodium-glucose transport protein 2 inhibitor use was significantly more prevalent in the ANE group (p = 0.013). Gastrointestinal symptoms were also significantly more pronounced in the ANE group, with vomiting occurring in 85.7% of patients compared to only 13.0% in the non-ANE group. Admission CT scans revealed further distinguishing features, with the ANE group showing significantly higher rates of esophageal wall thickening, intra-esophageal effusion, and calcification of the celiac artery origin (p < 0.0001, 0.0038, 0.0038, respectively). In conclusion, our study suggests that heavy alcohol consumption and strong gastrointestinal symptoms in DKA patients warrant a heightened suspicion of ANE. Early consideration of CT or upper gastrointestinal endoscopy is recommended in such cases.


Asunto(s)
Cetoacidosis Diabética , Esofagitis , Humanos , Cetoacidosis Diabética/complicaciones , Persona de Mediana Edad , Femenino , Masculino , Esofagitis/complicaciones , Esofagitis/patología , Adulto , Anciano , Tomografía Computarizada por Rayos X , Necrosis , Estudios Retrospectivos , Enfermedad Aguda
5.
Hinyokika Kiyo ; 70(1): 21-23, 2024 Jan.
Artículo en Japonés | MEDLINE | ID: mdl-38321746

RESUMEN

We report a case of testicular torsion in an 8-year-old who was referred to our hospital for right groin pain. He was diagnosed with right retractile testis during a 12-month check-up. However, instead of performing orchiopexy, he was placed under observation until the age of 5, after which he did not seek medical attention. Physical examination revealed swelling and tenderness in the right inguinal region and no palpable testis in the right scrotum. Ultrasound and computed tomography revealed right testicular torsion, and emergency surgery was performed. Intraoperative findings revealed a dark and ischemic testis that was twisted at 180°in the right inguinal region. There was no improvement in blood flow even after the testicular torsion was released; therefore, right orchidectomy with left orchiopexy was performed. Although the incidence of testicular torsion is higher in patients with an undescended testis than in those with a normally positioned scrotal position testis, reports of testicular torsion associated with a retractile testis are rare.


Asunto(s)
Criptorquidismo , Torsión del Cordón Espermático , Enfermedades Testiculares , Masculino , Humanos , Niño , Torsión del Cordón Espermático/cirugía , Testículo , Orquiectomía , Enfermedades Testiculares/cirugía , Criptorquidismo/complicaciones , Criptorquidismo/diagnóstico , Criptorquidismo/cirugía
6.
Proc Natl Acad Sci U S A ; 113(43): E6704-E6711, 2016 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-27791039

RESUMEN

Hybrid vigor or heterosis refers to the superior performance of F1 hybrid plants over their parents. Heterosis is particularly important in the production systems of major crops. Recent studies have suggested that epigenetic regulation such as DNA methylation is involved in heterosis, but the molecular mechanism of heterosis is still unclear. To address the epigenetic contribution to heterosis in Arabidopsis thaliana, we used mutant genes that have roles in DNA methylation. Hybrids between C24 and Columbia-0 (Col) without RNA polymerase IV (Pol IV) or methyltransferase I (MET1) function did not reduce the level of biomass heterosis (as evaluated by rosette diameter). Hybrids with a mutation in decrease in dna methylation 1 (ddm1) showed a decreased heterosis level. Vegetative heterosis in the ddm1 mutant hybrid was reduced but not eliminated; a complete reduction could result if there was a change in methylation at all loci critical for generating the level of heterosis, whereas if only a proportion of the loci have methylation changes there may only be a partial reduction in heterosis.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Metilación de ADN , Proteínas de Unión al ADN/genética , Epigénesis Genética , Regulación de la Expresión Génica de las Plantas , Genoma de Planta , Factores de Transcripción/genética , Arabidopsis/metabolismo , Biomasa , Cruzamientos Genéticos , ADN (Citosina-5-)-Metiltransferasas/deficiencia , ADN (Citosina-5-)-Metiltransferasas/genética , Proteínas de Unión al ADN/deficiencia , ARN Polimerasas Dirigidas por ADN/deficiencia , ARN Polimerasas Dirigidas por ADN/genética , Vigor Híbrido , Mutación , Factores de Transcripción/deficiencia
7.
Plant Physiol ; 175(4): 1760-1773, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29018096

RESUMEN

Histone acetylation is an essential process in the epigenetic regulation of diverse biological processes, including environmental stress responses in plants. Previously, our research group identified a histone deacetylase (HDAC) inhibitor (HDI) that confers salt tolerance in Arabidopsis (Arabidopsis thaliana). In this study, we demonstrate that class I HDAC (HDA19) and class II HDACs (HDA5/14/15/18) control responses to salt stress through different pathways. The screening of 12 different selective HDIs indicated that seven newly reported HDIs enhance salt tolerance. Genetic analysis, based on a pharmacological study, identified which HDACs function in salinity stress tolerance. In the wild-type Columbia-0 background, hda19 plants exhibit tolerance to high-salinity stress, while hda5/14/15/18 plants exhibit hypersensitivity to salt stress. Transcriptome analysis revealed that the effect of HDA19 deficiency on the response to salinity stress is distinct from that of HDA5/14/15/18 deficiencies. In hda19 plants, the expression levels of stress tolerance-related genes, late embryogenesis abundant proteins that prevent protein aggregation and positive regulators such as ABI5 and NAC019 in abscisic acid signaling, were induced strongly relative to the wild type. Neither of these elements was up-regulated in the hda5/14/15/18 plants. The mutagenesis of HDA19 by genome editing in the hda5/14/15/18 plants enhanced salt tolerance, suggesting that suppression of HDA19 masks the phenotype caused by the suppression of class II HDACs in the salinity stress response. Collectively, our results demonstrate that HDIs that inhibit class I HDACs allow the rescue of plants from salinity stress regardless of their selectivity, and they provide insight into the hierarchal regulation of environmental stress responses through HDAC isoforms.


Asunto(s)
Arabidopsis/efectos de los fármacos , Arabidopsis/fisiología , Histona Desacetilasas/metabolismo , Proteínas de Plantas/metabolismo , Salinidad , Sistemas CRISPR-Cas , Regulación Enzimológica de la Expresión Génica/fisiología , Regulación de la Expresión Génica de las Plantas/fisiología , Histona Desacetilasas/genética , Mutación , Análisis de Secuencia por Matrices de Oligonucleótidos , Proteínas de Plantas/genética , Cloruro de Sodio/toxicidad , Estrés Fisiológico
8.
Plant J ; 79(1): 127-38, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24798377

RESUMEN

Short interfering RNAs (siRNAs) homologous to transcriptional regulatory regions can induce RNA-directed DNA methylation (RdDM) and transcriptional gene silencing (TGS) of target genes. In our system, siRNAs are produced by transcribing an inverted DNA repeat (IR) of enhancer sequences, yielding a hairpin RNA that is processed by several Dicer activities into siRNAs of 21-24 nt. Primarily 24-nt siRNAs trigger RdDM of the target enhancer in trans and TGS of a downstream GFP reporter gene. We analyzed siRNA accumulation from two different structural forms of a trans-silencer locus in which tandem repeats are embedded in the enhancer IR and distinguished distinct RNA polymerase II (Pol II)- and Pol IV-dependent pathways of siRNA biogenesis. At the original silencer locus, Pol-II transcription of the IR from a 35S promoter produces a hairpin RNA that is diced into abundant siRNAs of 21-24 nt. A silencer variant lacking the 35S promoter revealed a normally masked Pol IV-dependent pathway that produces low levels of 24-nt siRNAs from the tandem repeats. Both pathways operate concurrently at the original silencer locus. siRNAs accrue only from specific regions of the enhancer and embedded tandem repeat. Analysis of these sequences and endogenous tandem repeats producing siRNAs revealed the preferential accumulation of siRNAs at GC-rich regions containing methylated CG dinucleotides. In addition to supporting a correlation between base composition, DNA methylation and siRNA accumulation, our results highlight the complexity of siRNA biogenesis at repetitive loci and show that Pol II and Pol IV use different promoters to transcribe the same template.


Asunto(s)
Arabidopsis/genética , ARN Polimerasas Dirigidas por ADN/genética , Regulación de la Expresión Génica de las Plantas , ARN Polimerasa II/genética , ARN Interferente Pequeño/genética , Secuencias Repetidas en Tándem/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Secuencia de Bases , Metilación de ADN , ARN Polimerasas Dirigidas por ADN/metabolismo , Silenciador del Gen , Genes Reporteros , Secuenciación de Nucleótidos de Alto Rendimiento , Meristema/genética , Meristema/metabolismo , Modelos Biológicos , Datos de Secuencia Molecular , Mutación , Brotes de la Planta/genética , Brotes de la Planta/metabolismo , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas/genética , ARN Polimerasa II/metabolismo , ARN de Planta/genética , ARN de Planta/metabolismo , ARN Interferente Pequeño/metabolismo , Análisis de Secuencia
9.
PLoS One ; 19(7): e0304281, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39038056

RESUMEN

BACKGROUND: The purpose of this study was to develop a model that can predict the postoperative visual acuity in eyes that had undergone vitrectomy for an epiretinal membrane (ERM). The Light Gradient Boosting Machine (LightGBM) was used to evaluate the accuracy of the prediction and the contribution of the explanatory variables. Two models were designed to predict the postoperative visual acuity in 67 ERM patients. Model 1 used the age, sex, affected eye, axial length, preoperative visual acuity, Govetto's classification stage, and OCT-derived vector information as features to predict the visual acuity at 1, 3, and 6 months postoperatively. Model 2 incorporated the early postoperative visual acuity as an additional variable to predict the visual acuity at 3, and 6 months postoperatively. LightGBM with 100 iterations of 5-fold cross-validation was used to tune the hyperparameters and train the model. This involved addressing multicollinearity and selecting the explanatory variables. The generalized performance of these models was evaluated using the root mean squared error (RMSE) in a 5-fold cross-validation, and the contributions of the explanatory variables were visualized using the average Shapley Additive exPlanations (SHAP) values. RESULTS: The RMSEs for the predicted visual acuity of Model 1 were 0.14 ± 0.02 logMAR units at 1 month, 0.12 ± 0.03 logMAR units at 3 months, and 0.13 ± 0.04 logMAR units at 6 months. High SHAP values were observed for the preoperative visual acuity and the ectopic inner foveal layer (EIFL) area with significant and positive correlations across all models. Model 2 that incorporated the postoperative visual acuity was used to predict the visual acuity at 3 and 6 months, and it had superior accuracy with RMSEs of 0.10 ± 0.02 logMAR units at 3 months and 0.10 ± 0.04 logMAR units at 6 months. High SHAP values were observed for the postoperative visual acuity in Model 2. CONCLUSION: Predicting the postoperative visual acuity in ERM patients is possible using the preoperative clinical data and OCT images with LightGBM. The contribution of the explanatory variables can be visualized using the SHAP values, and the accuracy of the prediction models improved when the postoperative visual acuity is included as an explanatory variable. Our data-driven machine learning models reveal that preoperative visual acuity and the size of the EIFL significantly influence postoperative visual acuity. Early intervention may be crucial for achieving favorable visual outcomes in eyes with an ERM.


Asunto(s)
Membrana Epirretinal , Aprendizaje Automático , Agudeza Visual , Vitrectomía , Humanos , Membrana Epirretinal/cirugía , Membrana Epirretinal/diagnóstico por imagen , Membrana Epirretinal/fisiopatología , Agudeza Visual/fisiología , Masculino , Femenino , Anciano , Persona de Mediana Edad , Periodo Posoperatorio , Tomografía de Coherencia Óptica/métodos
10.
Plant J ; 70(5): 750-8, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22269081

RESUMEN

Methylation of histone H3 lysine 9 (H3K9me) and small RNAs are associated with constitutively silent chromatin in diverse eukaryotes including plants. In plants, silent transposons are also marked by cytosine methylation, especially at non-CpG sites. Transposon-specific non-CpG methylation in plants is controlled by small RNAs and H3K9me. Although it is often assumed that small RNA directs H3K9me, interaction between small RNA and H3K9me has not been directly demonstrated in plants. We have previously shown that a mutation in the chromatin remodeling gene DDM1 (DECREASE IN DNA METHYLATION 1) induces a global decrease but a local increase of cytosine methylation and accumulation of small RNA at a locus called BONSAI. Here we show that de novo BONSAI methylation does not depend on RNAi but does depend on H3K9me. In mutants of H3K9 methyltransferase gene KRYPTONITE or the H3K9me-dependent DNA methyltransferase gene CHROMOMETHYALSE3, the ddm1-induced de novo cytosine methylation was abolished for all three contexts (CpG, CpHpG and CpHpH). Furthermore, RNAi mutants showed strong developmental defects when combined with the ddm1 mutation. Our results revealed unexpected interactions of epigenetic modifications that may be conserved among diverse eukaryotes.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Ensamble y Desensamble de Cromatina , Metilación de ADN , Proteínas de Unión al ADN/metabolismo , Factores de Transcripción/metabolismo , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/genética , Cromatina/genética , Cromatina/metabolismo , ADN de Plantas/genética , ADN de Plantas/metabolismo , Proteínas de Unión al ADN/genética , ADN-Citosina Metilasas/genética , ADN-Citosina Metilasas/metabolismo , Epigénesis Genética , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Sitios Genéticos , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Histonas/genética , Histonas/metabolismo , Mutación , Polinización , Interferencia de ARN , Autofecundación , Factores de Transcripción/genética
11.
Artículo en Inglés | MEDLINE | ID: mdl-24050070

RESUMEN

We conducted this study to determine the use of Japanese municipal information sources about the 2009 H1N1 influenza pandemic among 109 pregnant Japanese women during October and November 2009 and to determine their attitudes regarding the pandemic. During November 2009, the number of municipality information users increased significantly, however, the percentage of public magazine users remained under 40% and the percentage of municipality website users remained significantly lower than other website users. The accession of municipality information did not alleviate the anxiety of subjects caused by inaccurate information, such as mortality due to the virus infection and the safety of oseltamivir use. Those who obtained information about the pandemic from the municipality were more willing to receive the influenza vaccine than non-users. The results show the municipality information system needs to be improved to ameliorate anxiety and more effectively convey health information for future pandemics. Other Japanese public health service information systems shoud be assessed as well to determine their efficacy in delivering information regarding the 2009 H1N1 influenza pandemic.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Subtipo H1N1 del Virus de la Influenza A , Gripe Humana/epidemiología , Adulto , Ansiedad/epidemiología , Comportamiento del Consumidor , Información de Salud al Consumidor/métodos , Femenino , Conductas Relacionadas con la Salud , Educación en Salud/organización & administración , Humanos , Gripe Humana/prevención & control , Gripe Humana/virología , Japón/epidemiología , Pandemias/prevención & control , Percepción , Embarazo , Prevención Primaria/métodos
12.
J Clin Med ; 12(12)2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37373702

RESUMEN

Epiretinal membrane (ERM) foveoschisis is a recently proposed clinical entity. The purpose of this study was to compare the clinical characteristics and surgical outcomes of eyes with ERM foveoschisis to those of typical ERM. The medical records of all patients with ERM-related disorders examined between 2011 and 2020 were reviewed. ERM foveoschisis was defined by the clinical criteria proposed by an international panel of experts on ERMs. The background factors, clinical characteristics, and surgical outcomes of ERM foveoschisis were compared to those of typical ERM. Forty eyes with ERM foveoschisis were compared to 333 eyes with typical ERM. The percentage of women was significantly higher in the ERM foveoschisis group (92.5%) than in the typical ERM group (48.9%, p < 0.001). The central macular thickness (CMT) was significantly thinner in the ERM foveoschisis group (340 ± 110 µm) than in the typical ERM groups (476 ± 111 µm, p < 0.01). The degree of improvement in the best-corrected visual acuity (BCVA) three months after the surgery did not differ between the two groups (p = 0.59). These results suggest that the ERM foveoschisis is more likely to occur in women and that the prognosis after surgery is comparable to typical ERM.

13.
Sci Rep ; 13(1): 15542, 2023 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-37731007

RESUMEN

Most primary hypothyroidism in adults is caused by chronic thyroiditis. Autoantibodies such as anti-thyroglobulin antibody (TgAb) and anti-thyroid peroxidase antibody (TPOAb) are involved in the pathogenesis of chronic thyroiditis. On the other hand, the clinical features of antibody-negative hypothyroidism are not clear. In this study, we aimed to determine the prevalence of thyroid-related autoantibodies in patients with primary hypothyroidism and to evaluate the differences in thyroid structure between antibody-positive and antibody-negative hypothyroidism. Among 804 patients who attended Kawasaki Medical School Hospital for thyroid hormone abnormalities or thyroid gland enlargement between January 1, 2010 and December 31, 2021, 237 patients with primary hypothyroidism who underwent thyroid antibody measurement and thyroid ultrasound examination were included. Participants were divided into groups according to antibody positivity/negativity, and differences in antibody positivity and thyroid structure were evaluated. In this study, 34.6% of patients had antibody-negative hypothyroidism. The positive rate of each antibody was 62.0% for TgAb and 49.4% for TPOAb. The participants with antibody-positive hypothyroidism had significantly larger thyroid gland on thyroid ultrasound examination (p < 0.05). Thyroid-stimulating hormone was significantly higher in participants with antibody-positive compared to antibody-negative hypothyroidism. The present study reveals a positive rate of thyroid-related autoantibodies in patients with hypothyroidism and the differences in thyroid structure between patients with and without antibodies. This study clearly show that the prevalence of antibody-negative chronic thyroiditis is quite high among hypothyroid patients, although this point needs confirmation by further investigations. The data in this study would be useful for the treatment of antibody-negative hypothyroid patients.


Asunto(s)
Bocio , Enfermedad de Hashimoto , Hipotiroidismo , Adulto , Humanos , Hipotiroidismo/epidemiología , Autoanticuerpos
14.
Plant J ; 66(5): 831-43, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21457364

RESUMEN

fwa is a late flowering epi-mutant in Arabidopsis thaliana. FWA is silenced by DNA methylation in vegetative tissue but is demethylated in the central cell of the female ovule and continues to be expressed in the endosperm from the maternal copy. FWA is stably silenced in A. thaliana, but in related Arabidopsis species, FWA expression and DNA methylation levels vary in vegetative tissue. In this study, we show that variation in FWA expression in field isolates having identical DNA sequences is associated with changes in DNA methylation and may change over time. Vegetative FWA expression is correlated with decreased methylation at non-CG sites in the region upstream of the transcription start site in species related to A. thaliana and we conclude that methylation of this region is critical for FWA silencing in these species. In A. thaliana, FWA expression is affected by methylation in regions both upstream and downstream of the transcription start site. Ectopic A. thaliana FWA expression causes a late flowering phenotype, but over-expression of Arabidopsis lyrata FWA does not. In A. thaliana, stable silencing of FWA to prevent late flowering may have evolved through the selection of large tandem repeats and spread of the critical methylated region to include these repeats.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Epigénesis Genética , Proteínas de Homeodominio/genética , Factores de Transcripción/genética , Arabidopsis/fisiología , Proteínas de Arabidopsis/metabolismo , Cruzamientos Genéticos , Metilación de ADN , ADN de Plantas/genética , Flores/fisiología , Regulación de la Expresión Génica de las Plantas , Silenciador del Gen , Variación Genética , Proteínas de Homeodominio/metabolismo , Secuencias Repetidas en Tándem , Factores de Transcripción/metabolismo , Sitio de Iniciación de la Transcripción , Transgenes
15.
Int J Mol Sci ; 13(8): 9900-9922, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22949838

RESUMEN

Natural variation is defined as the phenotypic variation caused by spontaneous mutations. In general, mutations are associated with changes of nucleotide sequence, and many mutations in genes that can cause changes in plant development have been identified. Epigenetic change, which does not involve alteration to the nucleotide sequence, can also cause changes in gene activity by changing the structure of chromatin through DNA methylation or histone modifications. Now there is evidence based on induced or spontaneous mutants that epigenetic changes can cause altering plant phenotypes. Epigenetic changes have occurred frequently in plants, and some are heritable or metastable causing variation in epigenetic status within or between species. Therefore, heritable epigenetic variation as well as genetic variation has the potential to drive natural variation.


Asunto(s)
Epigénesis Genética/genética , Regulación de la Expresión Génica de las Plantas , Variación Genética , Plantas/genética , Genoma de Planta , Fenómenos Fisiológicos de las Plantas
16.
Int J Mol Sci ; 13(7): 8696-8721, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22942729

RESUMEN

An allopolyploid is an individual having two or more complete sets of chromosomes derived from different species. Generation of allopolyploids might be rare because of the need to overcome limitations such as co-existing populations of parental lines, overcoming hybrid incompatibility, gametic non-reduction, and the requirement for chromosome doubling. However, allopolyploids are widely observed among plant species, so allopolyploids have succeeded in overcoming these limitations and may have a selective advantage. As techniques for making allopolyploids are developed, we can compare transcription, genome organization, and epigenetic modifications between synthesized allopolyploids and their direct parental lines or between several generations of allopolyploids. It has been suggested that divergence of transcription caused either genetically or epigenetically, which can contribute to plant phenotype, is important for the adaptation of allopolyploids.


Asunto(s)
Epigénesis Genética/fisiología , Regulación de la Expresión Génica de las Plantas/fisiología , Plantas/genética , Plantas/metabolismo , Ploidias , Transcripción Genética/fisiología
17.
Sci Rep ; 12(1): 17680, 2022 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-36271288

RESUMEN

Cushing's syndrome and subclinical Cushing's syndrome (SCS) are conditions of increased cortisol secretion from the adrenal glands. Cushing's syndrome includes adrenocorticotropic hormone (ACTH)-dependent Cushing's syndrome (Cushing's disease) and ACTH-independent Cushing's syndrome (AICS). The purpose of this study was to investigate the diagnostic potential of the cortisol / adrenocorticotropic hormone (ACTH) ratio (CAR) for diagnosis of Cushing's syndrome or SCS in adult subjects. This was a single-center, retrospective, observational study. This study enrolled 44 subjects with SCS, 14 AICS, 10 CD, and 248 non-Cushing's syndrome subjects who had undergone a 1 mg dexamethasone suppression test (1 mg DST). Definition of SCS was as follows: no physical signs characteristic of Cushing syndrome and cortisol was ≥ 83 nmol/L in 1 mg DST. The diagnostic potential of CAR for diagnosis of Cushing's syndrome was evaluated by comparing the correlation between CAR and after-load cortisol level in 1 mg DST. As the results, there was a strong positive correlation between CAR and after-load cortisol level in subjects with AICS (r = 0.800, p < 0.005). CAR was 10,040 ± 4170 nmol/pmol in subjects with NCS, 17,535 ± 10,246 nmol/pmol in SCS, 101,221 ± 18,009 nmol/pmol in AICS, and 4324 ± 2051 nmol/pmol in CD, all of which were significantly higher compared to those with AICS (p < 0.0005). The cutoff values of CAR for screening at our institution were 11,849.6 nmol/pmol for AICS (AUC 0.935, p < 0.005, sensitivity 92.3%, specificity 83.5%) and 7006.1 nmol/pmol for CD (AUC 0.714, p < 0.05, sensitivity 100.0%, specificity 46.8%). There was a positive correlation between CAR and adrenal adenoma diameter in subjects with AICS (r = 0.508, p < 0.05), but there was no correlation between tumor diameter and CAR in subjects with SCS and CD. In conclusion, high CAR indicates increased cortisol secretion from the adrenal glands. Since CAR is a simple indicator that can be easily evaluated by general practitioners as well as endocrinologists, we think CAR would be useful for the early detection of Cushing's syndrome.


Asunto(s)
Síndrome de Cushing , Adulto , Humanos , Síndrome de Cushing/diagnóstico , Hormona Adrenocorticotrópica , Hidrocortisona , Estudios Retrospectivos , Dexametasona
18.
Plant Mol Biol ; 77(4-5): 419-31, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21882042

RESUMEN

The merging of two different genomes occurs during the formation of amphidiploids, and the merged regulatory networks have the potential to generate a new gene expression pattern. We examined the genome-wide gene expression of two newly synthesized amphidiploids between Arabidopsis thaliana and the related species Arabidopsis lyrata subsp. lyrata and Arabidopsis halleri subsp. gemmifera. 1,137 (4.7%) and 1,316 (5.4%) of probesets showed differential gene expression in A. thaliana-A. halleri and A. thaliana-A. lyrata hybrids respectively, compared to the mid parent value and of these, 489 were in common. Genes that differed in expression between the parental lines tended to have an expression level in both hybrids differing from the mid parent value. In contrast to protein coding genes, there is little differential expression of transposons. Genes in the categories of chloroplast-targeted and response to stress were overrepresented in the non-additively expressed genes in both amphidiploids. As these genes have the potential to contribute directly to the plant phenotype, we suggest that rapid changes of gene expression in amphidiploids might be important for producing greater biomass.


Asunto(s)
Arabidopsis/genética , Genoma de Planta , Elementos Transponibles de ADN/genética , Diploidia , Dosificación de Gen , Duplicación de Gen , Perfilación de la Expresión Génica , Hibridación Genética , Fenotipo , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
19.
Plant Cell Rep ; 30(1): 81-8, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21072521

RESUMEN

DNA methylation is an important epigenetic modification regulating gene expression and transposon silencing. Although epigenetic regulation is involved in some agricultural traits, there has been relatively little research on epigenetic modifications of genes in Brassica rapa, which includes many important vegetables. In B. rapa, orthologs of DDM1, a chromatin remodeling factor required for maintenance of DNA methylation, have been characterized and DNA hypomethylated knock-down plants by RNAi (ddm1-RNAi plants) have been generated. In this study, we investigated differences of DNA methylation status at the genome-wide level between a wild-type (WT) plant and a ddm1-RNAi plant by methylation-sensitive amplification polymorphism (MSAP) analysis. MSAP analysis detected changes of DNA methylation of many repetitive sequences in the ddm1-RNAi plant. Search for body methylated regions in the WT plant revealed no difference in gene body methylation levels between the WT plant and the ddm1-RNAi plant. These results indicate that repetitive sequences are preferentially methylated by DDM1 genes in B. rapa.


Asunto(s)
Brassica rapa/genética , Metilación de ADN/genética , Proteínas de Plantas/metabolismo , Reacción en Cadena de la Polimerasa/métodos , Polimorfismo Genético , Análisis de Secuencia de ADN/métodos , Secuencia de Bases , Southern Blotting , Sistemas de Lectura Abierta/genética , Interferencia de ARN
20.
J Clin Med ; 9(9)2020 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-32887464

RESUMEN

BACKGROUND: To compare the effectiveness of intravitreal ranibizumab (IVR) and intravitreal aflibercept (IVA) performed with the treat-and-extend (TAE) regimen on eyes with diabetic macular edema (DME). PATIENTS AND METHODS: This is a retrospective study of 125 eyes of 125 treatment-naïve DME patients who received anti-VEGF injections at three consecutive monthly intervals as the loading phase. The changes in the best-corrected visual acuity (BCVA), central retinal thickness (CRT), diabetic retinopathy severity scale (DRSS), and total injection numbers were compared between the two anti-VEGF agents. RESULTS: Among 125 eyes, 26 eyes completed the treatment with the TAE regimen for 24 months (20.8%). Thirteen eyes of 13 patients (mean age, 70.9 ± 6.0 years) received intravitreal injections of 0.5 mg ranibizumab, and 13 eyes of 13 patients (65.9 ± 8.6 years) received 2 mg aflibercept. No significant differences were detected in the baseline demographics. At 24 months, BCVA was significantly improved in both groups; from 0.31 ± 0.19 to 0.10 ± 0.12 logMAR units for IVR and 0.41 ± 0.19 to 0.16 ± 0.28 logMAR units for IVA (p = 1.29 × 10-9). CRT was significantly reduced in both groups; 440.9 ± 69.3 to 307.5 ± 66.4 µm for IVR and 473.9 ± 71.5 to 317.8 ± 71.2 µm for IVA (p = 3.55 × 10-9). No significant differences were detected in the improvements of BCVA, CRT in both groups, and the total injection numbers for 24 months (11.0 ± 1.2 for the IVA group and 12.0 ± 1.0 the IVR group). DRSS was significantly improved in both groups (p = 0.0004 for IVR and p = 0.009 for IVA). CONCLUSION: No significant differences were detected in the improvements of BCVA or CRT and injection numbers between the IVR and IVA groups treated with the TAE regimen. These results indicate that the results of the treatment with both agents with the TAE regimen were equally effective, but only 20.8% of patients completed 24 months of continuous treatment with the TAE regimen. Synopsis: There are no significant differences regarding effectiveness between the IVR and IVA groups treated with the TAE regimen for DME eyes.

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