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OBJECTIVE: The aim of this study was to assess the outcomes and complications, such as tibiofemoral instability and recurrence of valgus deformity, of total knee arthroplasty for valgus knees with a new technique preserving the deep layer of the medial collateral ligament. METHODS: In this study 33 (4 male and 29 female) patients, and a total of 36 (26 knees with osteoarthritis and 10 with rheumatoid arthritis) knees with a standing femorotibial angle (FTA) of <170° were included. Posterior Stabilized (PS) implants were used in 34 knees, rotating hinged knee implants were used in 2 knees. The procedures were carried out by a single surgeon protecting the deep layer of the medial collateral ligament. The patients' average age at the time of the operation was 67.6 ± 12 years, and the average follow-up period was 9.0 ± 3 years (range, 4-15 years). The Japanese Orthopaedic Association (JOA) knee score, range of motion (ROM) (extension/flexion; measured in degrees), FTA (measured in degrees) and complications were investigated. RESULTS: The Japanese Orthopaedic Association knee score significantly improved from an average of 51 ± 12 points before the operation to 86 ± 9 points after the operation (P <0.001). The extension ROM and flexion ROM improved from, -13 ± 13° to a postoperative average of -2 ± 4°, and 115 ± 25° to a postoperative average of 125 ± 18° respectively (P <0.001). The standing FTA significantly improved from 158 ± 9° to an average of 173 ± 2° after the operation (P <0.001). Thirty-four knees with severe valgus deformity were operated on using pos- terior stabilised implants, while only two knees required constrained implants. During follow-up, no complications, such as tibiofemoral instability, recurrence of valgus deformity, patellar necrosis, deep infection, wound problems, or peroneal nerve paralysis were observed. CONCLUSION: This study has shown us that after performing TKA while preserving the d-MCL for valgus knee deformity good clinical results were obtained and no complications were observed. LEVEL OF EVIDENCE: Level IV, Therapeutic Study.
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Artroplastia do Joelho , Ligamentos Colaterais , Prótese do Joelho , Ligamento Colateral Médio do Joelho , Osteoartrite do Joelho , Artroplastia do Joelho/métodos , Ligamentos Colaterais/cirurgia , Feminino , Humanos , Articulação do Joelho/cirurgia , Masculino , Ligamento Colateral Médio do Joelho/cirurgia , Osteoartrite do Joelho/complicações , Osteoartrite do Joelho/cirurgia , Amplitude de Movimento ArticularRESUMO
Observing chromosomes is a time-consuming and labor-intensive process, and chromosomes have been analyzed manually for many years. In the last decade, automated acquisition systems for microscopic images have advanced dramatically due to advances in their controlling computer systems, and nowadays, it is possible to automatically acquire sets of tiling-images consisting of large number, more than 1000, of images from large areas of specimens. However, there has been no simple and inexpensive system to efficiently select images containing mitotic cells among these images. In this paper, a classification system of chromosomal images by deep learning artificial intelligence (AI) that can be easily handled by non-data scientists was applied. With this system, models suitable for our own samples could be easily built on a Macintosh computer with Create ML. As examples, models constructed by learning using chromosome images derived from various plant species were able to classify images containing mitotic cells among samples from plant species not used for learning in addition to samples from the species used. The system also worked for cells in tissue sections and tetrads. Since this system is inexpensive and can be easily trained via deep learning using scientists' own samples, it can be used not only for chromosomal image analysis but also for analysis of other biology-related images.
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Aprendizado Profundo , Inteligência Artificial , Processamento de Imagem Assistida por Computador , MicroscopiaRESUMO
BACKGROUND: Achieving a favorable pacing threshold with a Micra transcatheter pacing system (Micra-TPS) is needed to reduce battery depletion. In some cases, the threshold increases shortly after the device is implanted, and a higher pacing threshold may be required. This study aims to identify the causes and predictors of the increase in pacing threshold observed shortly after Micra-TPS implantation. METHODS: The study included 64 consecutive patients who underwent Micra-TPS implantation between 2017 and 2020. The patients were divided into two groups depending on their pacing threshold: the increased pacing threshold (IPT) group (threshold increased by ≥0.5 V/0.24 ms within 1 month of implantation) and the stable pacing threshold (SPT) group. RESULTS: Excluding four patients who could not be followed up, of the 60 remaining patients, nine (15%) were in the IPT group and 51 (85%) were in the SPT group. The IPT group had significantly lower implant impedance values and higher implant thresholds than the SPT group (582 ± 59 vs 755 ± 167 Ω [P < .001] and 1.29 ± 0.87 vs 0.71 ± 0.40 V/0.24 ms [P = .014]). Implant impedance and threshold may serve as predictors of a threshold increase after implantation (area under the curve: 0.737-0.943 and 0.586-0.926, respectively). CONCLUSIONS: An IPT was noted shortly after Micra-TPS implantation owing to micro-dislodgement because of insufficient anchoring of the device to the myocardium. Impedance >660 Ω and threshold <1.0 V/0.24 ms may predict an increase in pacing threshold.
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Arritmias Cardíacas/terapia , Estimulação Cardíaca Artificial/métodos , Marca-Passo Artificial , Idoso , Cateterismo Cardíaco , Fontes de Energia Elétrica , Desenho de Equipamento , Análise de Falha de Equipamento , Feminino , Humanos , Masculino , MiniaturizaçãoRESUMO
BACKGROUND: Although exercise is a standard treatment for postoperative osteoarthritis, interindividual differences have been reported. Epigenetic modification (DNA methylation), a factor causing interindividual differences, is altered by the environment and may affect all tissues. Performing a tissue biopsy to investigate methylation of skeletal muscle fat metabolism genes is invasive, and less invasive and convenient alternatives such as blood testing are desired. However, the relationship between tissue and blood is still unclear. Here, we examined the relationship between DNA methylation of the PDK4 gene in skeletal muscle and peripheral blood. PATIENTS AND METHODS: Five patients who underwent artificial knee arthroplasty between April 2017 and June 2018 at Kansai Medical University Hospital were included (2 men and 3 women; average age, 75.2 years; body mass index, 26.1 kg/m2). We measured the body composition of the patients using dual-energy X-ray absorptiometry. Peripheral blood was collected at the time of hospitalization and 5 months after surgery; skeletal muscles were collected at the time of surgery and 5 months after surgery. Rehabilitation was performed according to the clinical procedure for 3 months after surgery. Patients performed resistance training and aerobic exercise using an ergometer for 20 min twice a week. Biopsy samples were treated with bisulfite after DNA extraction, and the methylation rate was calculated at different CpG islands downstream from the transcription initiation codon of the PDK4 gene. RESULTS: No significant change in body composition was observed before and after postoperative exercise therapy, and no significant change was noted in the methylation at each position in the promoter region of PDK4 in the skeletal muscle and peripheral blood. However, changes in the methylation rate at CpG1 in peripheral blood significantly correlated with those in skeletal muscle (P = 0.037). Furthermore, the amount of change in the methylation rate of CpG1 in the skeletal muscle was significantly correlated (P = 0.037) with the average methylation rate at the promoter region in peripheral blood. CONCLUSIONS: Methylation rates at CpG1 in the skeletal muscle and peripheral blood were significantly correlated, suggesting that skeletal muscle methylation could be analyzed via peripheral blood rather than skeletal muscle biopsy.
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Artroplastia do Joelho/estatística & dados numéricos , Metilação de DNA , Epigênese Genética , Terapia por Exercício/estatística & dados numéricos , Músculo Esquelético/metabolismo , Piruvato Desidrogenase Quinase de Transferência de Acetil/genética , Idoso , Feminino , Humanos , Japão , Masculino , Piruvato Desidrogenase Quinase de Transferência de Acetil/sangue , Piruvato Desidrogenase Quinase de Transferência de Acetil/metabolismoRESUMO
In Mongolia, cardiovascular disease is the leading cause of death, and prevalence of hypertension is very high. The aim of this study was to investigate the association between hypertension and sociodemographic factors and health-related behaviors among men in Darkhan-Uul Province, Mongolia. This cross-sectional study was conducted between November 2015 and January 2016. Men whose wives were pregnant with ≤ 20 weeks gestation and had attended antenatal health checkups at public health facilities were recruited in this study. The data were collected as part of a survey of pregnant women and their partners. Data were collected using self-administered questionnaires, anthropometry, and spot urine samples. A total of 224 men participated in the survey, and data from 209 participants were included in the analysis. Multiple logistic regression analysis showed that men with higher BMI had higher odds of hypertension than those with lower BMI (adjusted odds ratio [AOR]: 1.14, 95% CI: 1.03-1.26). Those with urinary cotinine > 100 ng/ml (smokers) had a lower risk of hypertension (AOR: 0.24, 95% CI: 0.09-0.67) compared to participants with urinary cotinine/ml (nonsmokers). This is the first study to investigate the association between hypertension and sociodemographic factors and health-related behaviors among men in Mongolia. Based on the findings of this study, clinicians responsible for public health in Mongolia should provide health education regarding the importance of weight control in preventing hypertension.
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More than half of women are reported to be overweight or obese in Mongolia, thus becoming a big health issue. Though maternal obesity is a known risk factor for cesarean section (CS), it remains unclear how much a high maternal body mass index (BMI) would influence the risk of CS among pregnant women in Mongolia. This study aimed to investigate whether a higher maternal BMI is related to CS delivery in Darkhan-Uul Province, Mongolia. Pregnant women at 20 weeks' gestation or less who visited public health facilities for antenatal health checkups between November 2015 and January 2016 were recruited. Data were collected using self-administered questionnaires, body weight measurement, and medical records. In total, 508 pregnant women participated, and data from 336 women were analyzed. Multiple logistic regression analysis showed that higher maternal BMI at first antenatal care visit (adjusted odds ratio [AOR] = 1.102, p = .033), higher gestational weight gain (AOR = 1.111, p = .001), older maternal age (AOR = 1.076, p = .030), and gestational age at delivery (AOR = 0.765, p = .005) were associated with CS delivery. This study is the first to demonstrate that higher maternal BMI and higher gestational weight gain are associated with CS delivery in Mongolia. Moreover, older maternal age and lower gestational age at delivery were found to be associated with CS delivery. Preventing obesity among women is important not only from the viewpoint of prevention of lifestyle diseases but also from the obstetric point of view; it is important for medical personnel to communicate the importance of preventing obesity to all women in Mongolia.
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PURPOSE: DNA methylation is thought to play a role in exercise-induced gene expression. We aimed to examine changes in muscular strength and body composition in elderly patients with end-stage knee osteoarthritis before and after artificial knee arthroplasty and exercise therapy. We aimed to confirm the relationship between DNA methylation and body composition, using the methylation rate of the pyruvate dehydrogenase kinase 4 (PDK4) gene that regulates skeletal muscle and fat metabolism. PATIENTS AND METHODS: Patients underwent artificial knee arthroplasty between April 2017 and June 2017 at Kansai Medical University Hospital. Six patients (seven knees) were included in the analysis (four males/two females; average age, 75.7 years; body mass index, 25.1 kg/m2). Body composition and knee extension muscle strength were measured before surgery and 5 months after surgery. Rehabilitation was performed for 3 months after surgery. In the remaining 2 months, patients performed resistance training and aerobic exercise using an ergometer for 20 mins, twice a week. A biopsy of the vastus medialis was taken during surgery and 5 months post-surgery. Biopsy samples were treated with bisulfite after DNA extraction, and DNA methylation rate was calculated. RESULTS: Body weight (P=0.046), total weight (P=0.027), and total fat mass (P=0.028) were significantly lower 5 months postoperatively than preoperatively. Five months post-surgery, the PDK4 gene was significantly more hypomethylated at eight sites in the CpG island, compared to pre-surgery. There was a significant correlation (r=0.88, P=0.02) between promoter region hypomethylation and weight loss. Total methylation rate and weight loss were significantly correlated (r=0.829, P=0.042). Total methylation rate and decrease in total fat mass showed a positive trending relationship (r=0.812, P=0.05). CONCLUSION: Rehabilitative exercise resulted in significant decreases in weight and body fat. Hypomethylation of the PDK4 gene promoter region signified the effect of postoperative management focus on exercise therapy on weight and fat loss.
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Artroplastia do Joelho , Metilação de DNA/genética , Epigênese Genética/genética , Terapia por Exercício/métodos , Proteínas Quinases/metabolismo , Tecido Adiposo , Idoso , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular/fisiologia , Ativação Transcricional , Redução de PesoRESUMO
This study aimed to compare knowledge about smoking, including passive smoking, and urinary cotinine (UC) levels in pregnant women and their partners in Mongolia. The study was conducted between November 2015 and January 2016 in Darkhan-Uul Province, Mongolia. Pregnant women with less than 20 weeks' gestation were recruited, and their partners were also invited to participate. Self-administered questionnaires and urine samples were used to collect data. Knowledge about smoking including passive smoking was measured using 14 questions. Data were analyzed using a Student's t-test, a chi-squared test, a one-way analysis of variance, and the Tukey-Kramer method for post-hoc analysis. Correlations were measured by computing Pearson's r or Spearman's ρ. A total of 508 pregnant women and 227 partners participated in this study; of these, 221 couples' data were analyzed. Pregnant women's scores on knowledge about smoking and passive smoking were significantly higher than those of their partners (9.4 ± 2.9 and 8.7 ± 3.1, respectively; p = 0.017). Pregnant women's and their partners' scores were slightly correlated (r = 0.163, p = 0.015). Pregnant women's and their partners' UC levels were significantly correlated (ρ = 0.250, p < 0.001). This study is the first to examine knowledge about smoking and passive smoking and UC levels among pregnant women and their partners in Mongolia. Because pregnant women's and their partners' scores and UC levels were positively correlated, health education on the harm caused by smoking and passive smoking should be provided to both pregnant women and their partners.
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Three transgenic HOSUT lines of winter wheat, HOSUT12, HOSUT20, and HOSUT24, each harbor a single copy of the cDNA for the barley sucrose transporter gene HvSUT1 (SUT), which was fused to the barley endosperm-specific Hordein B1 promoter (HO; the HOSUT transgene). Previously, flow cytometry combined with PCR analysis demonstrated that the HOSUT transgene had been integrated into different wheat chromosomes: 7A, 5D, and 4A in HOSUT12, HOSUT20, and HOSUT24, respectively. In order to confirm the chromosomal location of the HOSUT transgene by a cytological approach using wheat aneuploid stocks, we crossed corresponding nullisomic-tetrasomic lines with the three HOSUT lines, namely nullisomic 7A-tetrasomic 7B with HOSUT12, nullisomic 5D-tetrasomic 5B with HOSUT20, and nullisomic 4A-tetrasomic 4B with HOSUT24. We examined the resulting chromosomal constitutions and the presence of the HOSUT transgene in the F2 progeny by means of chromosome banding and PCR. The chromosome banding patterns of the critical chromosomes in the original HOSUT lines showed no difference from those of the corresponding wild type chromosomes. The presence or absence of the critical chromosomes completely corresponded to the presence or absence of the HOSUT transgene in the F2 plants. Investigating telocentric chromosomes occurred in the F2 progeny, which were derived from the respective critical HOSUT chromosomes, we found that the HOSUT transgene was individually integrated on the long arms of chromosomes 4A, 7A, and 5D in the three HOSUT lines. Thus, in this study we verified the chromosomal locations of the transgene, which had previously been determined by flow cytometry, and moreover revealed the chromosome-arm locations of the HOSUT transgene in the HOSUT lines.
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This cross-sectional study investigated the prevalence of smoking and secondhand smoking (SHS) among pregnant women in Darkhan-Uul Province, Mongolia, using urinary cotinine (UC) levels, and clarified the factors related to SHS exposure. It targeted pregnant women who underwent antenatal health check-ups from November 2015 to January 2016. Self-administered questionnaires and urine samples were used to collect data. Using UC levels as the criterion, it was found that the prevalence of smokers (>100 ng/ml) among 493 pregnant women was 11.8%, while SHS exposure (≥5 ng/ml) among nonsmokers was 44.8%. Older and highly educated women had lower odds of SHS exposure (p = 0.006 and 0.002, respectively). Furthermore, nonsmoking pregnant women from homes where smoking was permitted had higher odds of SHS exposure compared to women from homes where smoking was not permitted. These results suggest that community guidance programs, such as home smoking cessation that include families, are necessary.
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Exposição Ambiental/análise , Gestantes , Poluição por Fumaça de Tabaco/estatística & dados numéricos , Adulto , Cotinina/urina , Feminino , Humanos , Mongólia/epidemiologia , Análise Multivariada , Gravidez , Prevalência , Fatores de Risco , AutorrelatoRESUMO
Investigations into the epigenetic status of individual cells within tissues can produce both epigenetic data for different cell types and positional information of the cells. Thus, these investigations are important for understanding the intra- and inter-cellular control systems of developmental and environmental responses in plants. However, a simple method to detect epigenetic modifications of individual cells in plant tissues is not yet available because detection of the modifications requires immunohistochemistry using specific antibodies. In this study, we developed a simple immunohistochemical method that does not require sectioning to investigate epigenetic modifications. This method uses a clearing system to detect methylated histones, acetylated histones, methylated DNA and/or centromeric histone H3 variants. Analyses of four dicots and five monocots indicated that this method provides a universal technique to investigate epigenetic modifications in diverse plant species.
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Epigênese Genética , Imuno-Histoquímica/métodos , Proteínas de Plantas/genética , Ureia/química , Xilitol/química , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteína Centromérica A/genética , Proteína Centromérica A/metabolismo , Alho/genética , Alho/crescimento & desenvolvimento , Alho/metabolismo , Helianthus/genética , Helianthus/crescimento & desenvolvimento , Helianthus/metabolismo , Histonas/genética , Histonas/metabolismo , Hordeum/genética , Hordeum/crescimento & desenvolvimento , Hordeum/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Nicotiana/genética , Nicotiana/crescimento & desenvolvimento , Nicotiana/metabolismo , Triticum/genética , Triticum/crescimento & desenvolvimento , Triticum/metabolismo , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , Zea mays/genética , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismoRESUMO
OBJECTIVE: To evaluate the clinical outcomes after total knee arthroplasty (TKA) using the Genesis II posterior stabilized prosthesis with a high-flex insert during the mid-term follow-up and to assess its effect on the Japanese lifestyle. MATERIALS AND METHODS: Fifty-three consecutive patients (8 men and 45 women) underwent primary TKA. The mean follow-up time was 76 months (5-9 years). Clinical results were assessed with the Japanese Orthopedic Association osteoarthritis knee rating score (JOA knee score), range of motion, and lifestyle changes. RESULTS: The postoperative JOA knee score improved significantly compared to the preoperative JOA knee score. The mean preoperative flexion range improved from 112° to 123° postoperatively (p < 0.05). Additionally, our findings showed that 39% of patients enjoyed a floor-sitting life preoperatively, but only 30% of patients enjoyed floor-sitting life postoperatively. CONCLUSION: The postoperative range of knee motion and JOA knee score improved after TKA using the Genesis II posterior stabilized prosthesis with a high-flex insert, but the number of patients who enjoyed floor-sitting life decreased from 39% to 30% because of feelings of fear and discomfort. LEVEL OF EVIDENCE: Level IV, Therapeutic study.
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Artroplastia do Joelho/reabilitação , Articulação do Joelho/cirurgia , Prótese do Joelho/efeitos adversos , Estilo de Vida , Amplitude de Movimento Articular , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Prospectivos , Desenho de Prótese , Recuperação de Função Fisiológica , Índice de Gravidade de Doença , Resultado do TratamentoRESUMO
The combination of the DNA sequence-specific recombination system Cre/LoxP and the DNA transposon system Activator (Ac)/Dissociation (Ds) has been used for insertional and deletional mutagenesis, as well as for the generation of artificial ring chromosomes in model plants such as Arabidopsis and tobacco. However, it takes a long time to complete this process, even in Arabidopsis. To overcome this issue, a new binary vector, pDLHC, has been developed to induce chromosomal rearrangements for a short time in rice. pDLHC has been found to be effective in the induction of deletions between two LoxPs in the T2 generation of "Nihon bare" expressing Ac TPase. pDLHC has potential for the efficient generation of various types of chromosomal rearrangements including deletions, inversions, translocations and artificial ring chromosomes in plants, and the detailed protocol for rice is described here.
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Cromossomos de Plantas , Técnicas Genéticas , Vetores Genéticos/genética , Oryza/genética , Agrobacterium/genética , Inversão Cromossômica , DNA Bacteriano , Integrases/genética , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase , Regiões Promotoras GenéticasRESUMO
Insertion mutagenesis using known DNA sequences such as T-DNA and transposons is an important tool for studies on gene function in plant sciences. The transposons Activator (Ac)/Dissociation (Ds) have been systematically used to manipulate plant chromosomes. For both of these applications, the recovery of genomic DNA sequences flanking the insertions is required to estimate the sizes and/or scales of the reconstituted chromosomes. In this chapter, we describe the protocols for thermal asymmetric interlaced PCR (TAIL-PCR) for isolation of genomic sequences flanking DNA inserts in plant genomes.
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Mapeamento Cromossômico/métodos , Cromossomos de Plantas , Elementos de DNA Transponíveis , DNA Bacteriano , Reação em Cadeia da Polimerase/métodos , Genoma de PlantaRESUMO
In Arabidopsis thaliana, various attempts have been made to create artificial chromosomes as a new tool for cytological and genetic analyses. However, most of the efforts have been unsuccessful until recently. Most eukaryotic chromosomes are linear, and therefore the Arabidopsis artificial chromosomes have also been designed to be linear and to carry the telomere structure at both ends. In contrast, circular artificial chromosomes were successfully created by the Cre/LoxP system combined with Ac/Ds transposon system, on the basis of the discovery that ring minichromosomes are relatively stable and transmissible to the next generations in A. thaliana. Because ring minichromosomes â¼1 to 6 Mb in size have been generated, in this article, the protocol for inducing large chromosomal rearrangements resulting in ring chromosome formation is described. © 2016 by John Wiley & Sons, Inc.
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The kinetochore is a protein complex including kinetochore-specific proteins that plays a role in chromatid segregation during mitosis and meiosis. The complex associates with centromeric DNA sequences that are usually species-specific. In plant species, tandem repeats including satellite DNA sequences and retrotransposons have been reported as centromeric DNA sequences. In this study on sunflowers, a cDNA-encoding centromere-specific histone H3 (CENH3) was isolated from a cDNA pool from a seedling, and an antibody was raised against a peptide synthesized from the deduced cDNA. The antibody specifically recognized the sunflower CENH3 (HaCENH3) and showed centromeric signals by immunostaining and immunohistochemical staining analysis. The antibody was also applied in chromatin immunoprecipitation (ChIP)-Seq to isolate centromeric DNA sequences and two different types of repetitive DNA sequences were identified. One was a long interspersed nuclear element (LINE)-like sequence, which showed centromere-specific signals on almost all chromosomes in sunflowers. This is the first report of a centromeric LINE sequence, suggesting possible centromere targeting ability. Another type of identified repetitive DNA was a tandem repeat sequence with a 187-bp unit that was found only on a pair of chromosomes. The HaCENH3 content of the tandem repeats was estimated to be much higher than that of the LINE, which implies centromere evolution from LINE-based centromeres to more stable tandem-repeat-based centromeres. In addition, the epigenetic status of the sunflower centromeres was investigated by immunohistochemical staining and ChIP, and it was found that centromeres were heterochromatic.
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Minichromosomes have been extensively used as tools for revealing the functional structures of eukaryotic chromosomes. However, the definition of a minichromosome is still ambiguous. Based on previous reports on various eukaryotes, minichromosomes are defined here to be chromosomes that are smaller than one third the size of the smallest chromosome in the given species. In Arabidopsis thaliana, therefore, chromosomes <8.5 Mb in length are classified as minichromosomes, although to date only six different minichromosomes have been found or created, probably due to their extremely small sizes that limit detection. Minichromosomes vary from 1.7 to 8.4 Mb in length and are much shorter than authentic chromosomes (25.3 to 38.0 Mb). Linear and circular minichromosomes have been identified, and both types are maintained as experimental lines. Most of the circular, ring-shaped minichromosomes in Arabidopsis are relatively stable at mitosis and transmissible to the next generation, regardless of the centromere form (dicentric or monocentric). Recently, a ring minichromosome was artificially generated by a combination of the Cre/LoxP and Ac/Ds systems. This artificial ring chromosome, AtARC1, has several advantages over the previously reported minichromosomes as a chromosome vector; therefore, this method of generating artificial ring chromosomes is expected to be improved for application to other plant species including important crops.
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Arabidopsis/genética , Cromossomos Artificiais/genética , Cromossomos de Plantas/genética , Genes de Plantas , Proteínas de Plantas/genética , Arabidopsis/química , Centrômero/química , Centrômero/genética , Cromossomos Artificiais/química , Cromossomos de Plantas/química , DNA de Plantas/genética , Mitose , Proteínas de Plantas/química , Cromossomos em Anel , Análise de Sequência de DNA , Telômero/química , Telômero/genéticaRESUMO
The centromere is a structurally and functionally specialized region present on every eukaryotic chromosome. Lotus japonicus is a model legume species for which there is very limited information on the centromere structure. Here we cloned and characterized the L. japonicus homolog of the centromere-specific histone H3 gene (LjCenH3) encoding a 159-amino acid protein. Using an Agrobacterium-based transformation system, LjCenH3 tagged with a green fluorescent protein was transferred into L. japonicus cells. The centromeric position of LjCENH3 protein was revealed on L. japonicus metaphase chromosomes by an immunofluorescence assay. The identification of LjCenH3 as a critical centromere landmark could pave the way for a better understanding of centromere structure in this model and other agriculturally important legume species.
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Centrômero/metabolismo , Histonas/genética , Lotus/genética , Proteínas de Plantas/genética , Sequência de Aminoácidos , Sequência de Bases , Centrômero/química , Histonas/química , Histonas/metabolismo , Lotus/química , Lotus/metabolismo , Dados de Sequência Molecular , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Ligação ProteicaRESUMO
A 30-year-old woman with a more than 6-month history of fever, weight loss, general fatigue and dysesthesia of lower extremities was admitted to our hospital with a diagnosis of infective endocarditis. Blood cultures revealed Staphylococcus oralis. Echocardiography revealed severe mitral and moderate tricuspid regurgitation, as well as massive vegetations and aneurysms on the mitral valve. Computed tomography revealed an abdominal aortic aneurysm, left common and external iliac arterial aneurysms, and occlusion of the left common iliac, the deep femoral arteries and the bilateral tibioperoneal trunk. The ankle brachial pressure indices (ABI) were 0.94 (right) and 0.61 (left). She initially underwent mitral valve replacement and tricuspid annuloplasty. On postoperative day 24, the affected segments of the arteries were replaced with a woven Dacron bifurcated graft after resection of the mycotic abdominal and the iliac arterial aneurysms. We could not obtain a sufficient amount of omental pedicle to wrap the prosthesis. Her postoperative course was uneventful and mycotic arterial embolism and aneurysm did not recur.
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Aneurisma Infectado/etiologia , Aneurisma da Aorta Abdominal/etiologia , Arteriopatias Oclusivas/etiologia , Endocardite/complicações , Aneurisma Cardíaco/etiologia , Aneurisma Ilíaco/etiologia , Insuficiência da Valva Mitral/complicações , Valva Mitral , Adulto , Aneurisma Infectado/cirurgia , Aneurisma da Aorta Abdominal/cirurgia , Arteriopatias Oclusivas/cirurgia , Implante de Prótese Vascular , Endocardite/diagnóstico , Feminino , Aneurisma Cardíaco/cirurgia , Implante de Prótese de Valva Cardíaca , Humanos , Aneurisma Ilíaco/cirurgia , Valva Mitral/cirurgia , Insuficiência da Valva Mitral/diagnóstico , Insuficiência da Valva Mitral/cirurgia , Resultado do TratamentoRESUMO
In higher eukaryotes, centromeres are typically composed of megabase-sized arrays of satellite repeats that evolve rapidly and homogenize within a species' genome. Despite the importance of centromeres, our knowledge is limited to a few model species. We conducted a comprehensive analysis of common bean (Phaseolus vulgaris) centromeric satellite DNA using genomic data, fluorescence in situ hybridization (FISH), immunofluorescence and chromatin immunoprecipitation (ChIP). Two unrelated centromere-specific satellite repeats, CentPv1 and CentPv2, and the common bean centromere-specific histone H3 (PvCENH3) were identified. FISH showed that CentPv1 and CentPv2 are predominantly located at subsets of eight and three centromeres, respectively. Immunofluorescence- and ChIP-based assays demonstrated the functional significance of CentPv1 and CentPv2 at centromeres. Genomic analysis revealed several interesting features of CentPv1 and CentPv2: (i) CentPv1 is organized into an higher-order repeat structure, named Nazca, of 528 bp, whereas CentPv2 is composed of tandemly organized monomers; (ii) CentPv1 and CentPv2 have undergone chromosome-specific homogenization; and (iii) CentPv1 and CentPv2 are not likely to be commingled in the genome. These findings suggest that two distinct sets of centromere sequences have evolved independently within the common bean genome, and provide insight into centromere satellite evolution.