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1.
Osteoarthritis Cartilage ; 30(10): 1344-1355, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35843479

RESUMO

OBJECTIVES: Nerve growth factor (NGF) and sensory nerves are key factors in established osteoarthritis (OA) knee pain. We investigated the time course of NGF expression and sensory nerve growth across early and late stages of OA progression in rat knees. DESIGN: Knee OA was induced by medial meniscectomy in rats. OA histopathology, NGF expression, and calcitonin gene-related peptide immunoreactive (CGRP-IR) nerves were quantified pre-surgery and post-surgery at weeks 1, 2, 4 and 6. Pain-related behavior was evaluated using dynamic weight distribution and mechanical sensitivity of the hind paw. RESULTS: NGF expression in chondrocytes increased from week 1 and remained elevated until the advanced stage. In synovium, NGF expression increased only in early stages, whereas in osteochondral channels and bone marrow, NGF expression increased in the later stages of OA progression. CGRP-IR nerve density in suprapatellar pouch peaked at week 4 and decreased at week 6, whereas in osteochondral channels and bone marrow, CGRP-IR innervation increased through week 6. Percent ipsilateral weight-bearing decreased throughout the OA time course, whereas reduced paw withdrawal thresholds were observed only in later stages. CONCLUSION: During progression of knee OA, time-dependent alterations of NGF expression and CGRP-IR sensory innervation are knee tissue specific. NGF expression increased in early stages and decreased in advanced stage in the synovium but continued to increase in osteochondral channels and bone marrow. Increases in CGRP- IR sensory innervation followed increases in NGF expression, implicating that NGF is a key driver of articular nerve growth associated with OA pain.


Assuntos
Osteoartrite do Joelho , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Articulação do Joelho/patologia , Fator de Crescimento Neural/metabolismo , Osteoartrite do Joelho/patologia , Dor/complicações , Ratos
2.
Phys Rev Lett ; 123(18): 185001, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31763903

RESUMO

The isotope effect on energy confinement time and thermal transport has been investigated for plasmas confined by a stellarator-heliotron magnetic field. This is the first detailed assessment of an isotope effect in a stellarator heliotron. Hydrogen and deuterium plasmas heated by neutral beam injection on the Large Helical Device have exhibited no significant dependence on the isotope mass in thermal energy confinement time, which is not consistent with the simple gyro-Bohm model. A comparison of thermal diffusivity for dimensionally similar hydrogen and deuterium plasmas in terms of the gyroradius, collisionality, and thermal pressure has clearly shown robust confinement improvement in deuterium to compensate for the unfavorable mass dependence predicted by the gyro-Bohm model.

3.
Mol Psychiatry ; 21(7): 885-93, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27217147

RESUMO

Although numerous genetic studies have been conducted for bipolar disorder (BD), its genetic architecture remains elusive. Here we perform, to the best of our knowledge, the first trio-based exome sequencing study for BD to investigate potential roles of de novo mutations in the disease etiology. We identified 71 de novo point mutations and one de novo copy-number mutation in 79 BD probands. Among the genes hit by de novo loss-of-function (LOF; nonsense, splice site or frameshift) or protein-altering (LOF, missense and inframe indel) mutations, we found significant enrichment of genes highly intolerant (first percentile of intolerant genes assessed by Residual Variation Intolerance Score) to protein-altering variants in general population, an observation that is also reported in autism and schizophrenia. When we performed a joint analysis using the data of schizoaffective disorder in published studies, we found global enrichment of de novo LOF and protein-altering mutations in the combined group of bipolar I and schizoaffective disorders. Considering relationship between de novo mutations and clinical phenotypes, we observed significantly earlier disease onset among the BD probands with de novo protein-altering mutations when compared with non-carriers. Gene ontology enrichment analysis of genes hit by de novo protein-altering mutations in bipolar I and schizoaffective disorders did not identify any significant enrichment. These results of exploratory analyses collectively point to the roles of de novo LOF and protein-altering mutations in the etiology of bipolar disorder and warrant further large-scale studies.


Assuntos
Transtorno Bipolar/genética , Adolescente , Adulto , Exoma/genética , Família , Feminino , Predisposição Genética para Doença/genética , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Mutação/genética , Transtornos Psicóticos/genética , Análise de Sequência de DNA/métodos
5.
Catheter Cardiovasc Interv ; 87(6): 1092-100, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26268482

RESUMO

OBJECTIVE: To demonstrate the safety and efficacy of a new sirolimus eluting stent with bioresorbable polymer, Ultimaster, (BP-SES) compared with everolimus-eluting, permanent polymer, Xience stent (PP-EES) in bifurcation lesions with respect to the freedom from Target Lesion Failure at 1-year. METHODS: Within 1,119 patients enrolled in the CENTURY II randomized controlled multicenter trial, 194 patients were treated for bifurcation lesions and randomized to either BP-SES (n = 95) or PP-EES (n = 99). The primary endpoint was freedom from target lesion failure (TLF) composite endpoint [cardiac death, MI not clearly attributable to a non-target vessel, and clinically driven target lesion revascularization (TLR)] at 1-year. RESULTS: Baseline patient demographic, angiographic, and stenting characteristics were similar in both study arms. A single stent technique with provisional or "cross over" stenting were the most widely used in both arms (93.2% BP-SES vs. 92.4% PP-EES). Freedom from TLF at 1-year was 94.7% for BP-SES and 91.9% for PP-EES (P for noninferiority 0.031). The rate of clinically driven target lesion revascularization (TLR) at 1-year was 3.2% for BP-SES and 3.0% for PP-EES (P = 0.95). There were no significant differences detected in any of the individual clinical endpoints or other secondary clinical endpoints between the study arms at 1-year follow up. CONCLUSIONS: The new bioresorbable polymer sirolimus-eluting stent showed safety and efficacy profiles similar to durable polymer everolimus-eluting in the treatment of patients with bifurcation lesions at 1-year follow up. © 2015 Wiley Periodicals, Inc.


Assuntos
Implantes Absorvíveis , Vasos Coronários/diagnóstico por imagem , Stents Farmacológicos , Everolimo/farmacologia , Intervenção Coronária Percutânea/métodos , Polímeros , Sirolimo/farmacologia , Idoso , Angiografia Coronária , Doença da Artéria Coronariana , Vasos Coronários/cirurgia , Feminino , Seguimentos , Humanos , Imunossupressores/farmacologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Desenho de Prótese , Método Simples-Cego , Fatores de Tempo
7.
Gene Ther ; 22(2): 146-54, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25394252

RESUMO

Reduced expression in immortalized cells/Dickkopf-3 (REIC/Dkk-3) was identified as a gene whose expression is reduced in many human cancers. REIC/Dkk-3 expression is also downregulated in malignant glioma and regulates cell growth through caspase-dependent apoptosis. cRGD (EMD121974), an antagonist of integrins, has demonstrated preclinical efficacy against malignant glioma. In this study, we investigated the antiglioma effect of combination therapy using an adenovirus vector carrying REIC/Dkk-3 (Ad-REIC) and cRGD. Quantitative real-time reverse-transcription PCR revealed the reduction of REIC/Dkk-3 mRNA levels in malignant glioma cell lines. The reduction of REIC/Dkk-3 protein expression in malignant glioma cell lines was also confirmed with western blot analysis. After treatment with Ad-REIC and cRGD, the proliferative rate of malignant glioma cells was significantly reduced in a time-dependent manner. In vivo, there was a statistically significant increase in the survival of mice treated with Ad-REIC and cRGD combination therapy compared with Ad-REIC monotherapy. We identified an apoptotic effect following monotherapy with Ad-REIC. Moreover, cRGD augmented the antiglioma efficacy of Ad-REIC. These results may lead to a promising new approach for the treatment of malignant glioma.


Assuntos
Adenoviridae/genética , Antineoplásicos/farmacologia , Neoplasias Encefálicas/terapia , Glioma/terapia , Integrinas/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos Cíclicos/farmacologia , Proteínas Adaptadoras de Transdução de Sinal , Animais , Antineoplásicos/uso terapêutico , Apoptose , Astrócitos/metabolismo , Caspase 8/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Quimiocinas , Terapia Combinada , Feminino , Técnicas de Silenciamento de Genes , Terapia Genética , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Venenos de Serpentes , Transdução Genética , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Phys Rev Lett ; 113(12): 121301, 2014 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-25279618

RESUMO

Bosonic superweakly interacting massive particles (super-WIMPs) are a candidate for warm dark matter. With the absorption of such a boson by a xenon atom, these dark matter candidates would deposit an energy equivalent to their rest mass in the detector. This is the first direct detection experiment exploring the vector super-WIMPs in the mass range between 40 and 120 keV. With the use of 165.9 day of data, no significant excess above background was observed in the fiducial mass of 41 kg. The present limit for the vector super-WIMPs excludes the possibility that such particles constitute all of dark matter. The absence of a signal also provides the most stringent direct constraint on the coupling constant of pseudoscalar super-WIMPs to electrons. The unprecedented sensitivity was achieved exploiting the low background at a level 10(-4) kg-1 keVee-1 day-1 in the detector.

9.
Water Sci Technol ; 69(7): 1573-80, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24718353

RESUMO

Three large wastewater treatment plants in Sweden participate in a project evaluating different types of ammonium feedback controllers in full-scale operation. The goal is to improve process monitoring, maintain effluent water quality and save energy. The paper presents the outcome of the long-term evaluation of controllers. Based on the experiences gained from the full-scale implementations, a discussion is provided about energy assessment for the purpose of comparing control strategies. The most important conclusions are the importance of long-term experiments and the difficulty of comparing energy consumption based on air flow rate measurements.


Assuntos
Compostos de Amônio/química , Conservação de Recursos Energéticos , Retroalimentação , Gerenciamento de Resíduos , Suécia
10.
Rev Sci Instrum ; 95(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39037297

RESUMO

The cross-field transport in the scrape-off-layers (SOLs) and divertors in tokamaks is of a similar size to the poloidal component of the parallel flow, thereby significantly impacting the plasma transport there. However, its direct observation has been challenging because the drift velocity (102-103 m/s) is significantly below the detection limit of conventional diagnostics. To realize cross-field ion flow measurement, a variety of systematic uncertainties in the system must be narrowed down. Here, we develop a conceptual design of the Doppler spectrometry that enables us to measure the impurity flows with 102-m/s accuracy based on an in situ wavelength-calibration technique developed in the astrophysics field, the iodine-cell method. We discuss its properties and applicability. In particular, the scaling relation between wavelength accuracy and various spectroscopic parameters is newly presented, which suggests the high importance of the wavelength resolution of the system. Based on transport simulations for the JT-60SA divertor, the feasibility of the system is assessed.

11.
Pharmacogenomics J ; 13(2): 110-20, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22231567

RESUMO

Human organic cation transporter 3 (OCT3 and SLC22A3) mediates the uptake of many important endogenous amines and basic drugs in a variety of tissues. OCT3 is identified as one of the important risk loci for prostate cancer, and is markedly underexpressed in aggressive prostate cancers. The goal of this study was to identify genetic and epigenetic factors in the promoter region that influence the expression level of OCT3. Haplotypes that contained the common variants, g.-81G>delGA (rs60515630) (minor allele frequency 11.5% in African American) and g.-2G>A (rs555754) (minor allele frequency>30% in all ethnic groups) showed significant increases in luciferase reporter activities and exhibited stronger transcription factor-binding affinity than the haplotypes that contained the major alleles. Consistent with the reporter assays, OCT3 messenger RNA expression levels were significantly higher in Asian (P<0.001) and Caucasian (P<0.05) liver samples from individuals who were homozygous for g.-2A/A in comparison with those homozygous for the g.-2G/G allele. Studies revealed that the methylation level in the basal promoter region of OCT3 was associated with OCT3 expression level and tumorigenesis capability in various prostate cancer cell lines. The methylation level of the OCT3 promoter was higher in 62% of prostate tumor samples compared with matched normal samples. Our studies demonstrate that genetic polymorphisms in the proximal promoter region of OCT3 alter the transcription rate of the gene and may be associated with altered expression levels of OCT3 in human liver. Aberrant methylation contributes to the reduced expression of OCT3 in prostate cancer.


Assuntos
Metilação de DNA/genética , Epigenômica , Proteínas de Transporte de Cátions Orgânicos/genética , Neoplasias da Próstata/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Farmacológicos/metabolismo , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Etnicidade/genética , Feminino , Regulação da Expressão Gênica , Frequência do Gene , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Regiões Promotoras Genéticas , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia
12.
J Appl Microbiol ; 115(3): 718-26, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23782224

RESUMO

AIMS: Digested sludge (DS) is a major waste product of anaerobic digestion of sewage sludge and is resistant to biodegradation. In this study, we isolated and characterized DS-assimilating fungi from soil. METHODS AND RESULTS: We tried to isolate DS-assimilating strains by enrichment culture using DS as the nutrient source, but microbial growth was not observed in any culture. To eliminate the inhibitory effect of metals in DS on microbial growth, acid-treated DS was subsequently used for enrichment, and eight fungal strains were isolated from the subcultures. At least 10-30% reduction in sludge was observed after 1-week cultivation, and prolonged cultivation led to further sludge reduction. All isolates produced xylanase, chitinase and keratinase. Phylogenetic analysis revealed that the isolates were Penicillium, Fusarium, Chaetomium, Cunninghamella, Neosartorya and Umbelopsis. Some isolates were suggested novel species. CONCLUSIONS: To the best of our knowledge, our study is the first to report the isolation of DS-assimilating strains. SIGNIFICANCE AND IMPACT OF THE STUDY: These isolates may be useful for commercial production of microbial enzymes using DS as the substrate. Because xylan, chitin and keratin in sludge-hyphae complexes are considered to be partially depolymerized, this material could also be utilized as a readily available fertilizer.


Assuntos
Fungos/enzimologia , Fungos/isolamento & purificação , Esgotos/microbiologia , Biodegradação Ambiental , Quitinases/metabolismo , Fertilizantes , Fungos/classificação , Peptídeo Hidrolases/metabolismo , Filogenia , Esgotos/química , Microbiologia do Solo , Xilosidases/metabolismo
15.
Phys Rev Lett ; 109(21): 213001, 2012 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-23215591

RESUMO

The mechanism of DNA modification induced by K-shell photoabsorption of nitrogen and oxygen atoms was investigated by electron paramagnetic resonance and x-ray absorption near edge structure measurements of calf thymus DNA. A g factor of 2.000 for the unpaired electron species, which only arises during irradiation, was measured. The EPR intensities for DNA zwere twofold times larger than those estimated based on the photoabsorption cross section. This suggests that the DNA film itself forms unpaired electron species through the excitation of enhanced electron recapturing, known as the postcollision interaction process.


Assuntos
DNA/química , Elétrons , Nitrogênio/química , Oxigênio/química , Absorção , Animais , Bovinos , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Processos Fotoquímicos
16.
Br J Dermatol ; 167(2): 252-61, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22404487

RESUMO

BACKGROUND: Antidesmoglein (anti-Dsg) 3 serum antibody titres are usually correlated with the disease activity of pemphigus vulgaris (PV), but some patients retain high titres even in remission. OBJECTIVES: The aim of our study was to determine whether anti-Dsg3 antibodies in PV sera recognized calcium (Ca(2+) )-dependent or non-Ca(2+) -dependent epitopes, and to evaluate their pathogenicity. METHODS: Dsg3 baculoprotein-coated enzyme-linked immunosorbent assay (ELISA) plates were treated with 0.5 mmol L(-1) ethylenediaminetetraacetic acid (EDTA). The binding ability of anti-Dsg3 monoclonal antibodies (mAbs) was analysed. Eight of the 83 patients with PV who were screened had elevated Dsg3 ELISA index values > 00 in remission. The binding ability of these PV sera was analysed. We evaluated the pathogenicity of anti-Dsg3 serum antibodies against the non-Ca(2+) -dependent epitopes using a dissociation assay. RESULTS: The reactivity of pathogenic anti-Dsg3 mAbs against the Ca(2+) -dependent epitopes diminished markedly in the EDTA-treated ELISA, whereas no such reduction was observed in mAbs against the non-Ca(2+) -dependent epitopes. The sera of all the patients contained antibodies against both Ca(2+) -dependent and non-Ca(2+) -dependent epitopes. In six out of the eight patients, the ratio of antibodies against Ca(2+) -dependent to non-Ca(2+) -dependent epitopes decreased in remission. EDTA-treated Dsg3 baculoproteins adsorbed anti-Dsg3 serum antibodies against the non-Ca(2+) -dependent epitopes, but the remnant PV antibodies retained the ability to induce acantholysis in the dissociation assay. CONCLUSIONS: We have established an assay to measure indirectly the titres of anti-Dsg3 serum antibodies against the Ca(2+) -dependent epitopes, based on the differences between EDTA-untreated and EDTA-treated ELISA index values, as a routine laboratory test to reflect the pathogenic anti-Dsg3 serum antibody titres more accurately.


Assuntos
Anticorpos Monoclonais/metabolismo , Cálcio/imunologia , Desmogleína 3/imunologia , Epitopos/imunologia , Pênfigo/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Autoanticorpos/imunologia , Relação Dose-Resposta Imunológica , Ácido Edético/farmacologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/farmacologia , Estudos Retrospectivos
17.
Pharmacopsychiatry ; 45(7): 279-83, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22592502

RESUMO

An increased incidence of sudden death has been observed among patients treated with antidepressants. A prolonged QTc interval is a known prognostic factor for fatal arrhythmia, and several studies have shown that the use of antidepressants can cause a prolonged QTc interval. However, few studies, especially in Japan, have compared the effects of multiple drugs on QTc interval or examined dose relationships in a clinical setting.We compared the effects of antidepressants on QT interval, corrected to QTc by Bazett's formula, in 729 Japanese patients who were diagnosed with mood disorder.Using stepwise multiple linear regression analysis, we found that the use of tricyclic antidepressants (P<0.01) and concomitant use of antipsychotics (P<0.05), as well as advanced age and being female (known factors for prolonged QTc interval; both P<0.01), significantly prolonged the QTc interval. Analysis of individual antidepressants also revealed that the use of clomipramine (P<0.01) and amitriptyline (P<0.05) significantly prolonged the QTc interval.Our results reveal that tricyclic antidepressants, especially clomipramine and amitriptyline, confer a risk of prolonged QTc interval in a dose-dependent manner. The selective serotonin reuptake inhibitors investigated (fluvoxamine, paroxetine, sertraline) were not indicated as risk factors for QTc prolongation.


Assuntos
Antidepressivos Tricíclicos/efeitos adversos , Antipsicóticos/efeitos adversos , Povo Asiático/psicologia , Síndrome do QT Longo/induzido quimicamente , Transtornos do Humor/fisiopatologia , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos , Fatores Etários , Antidepressivos Tricíclicos/administração & dosagem , Antipsicóticos/administração & dosagem , Relação Dose-Resposta a Droga , Quimioterapia Combinada/efeitos adversos , Eletrocardiografia/psicologia , Eletrocardiografia/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos do Humor/tratamento farmacológico , Análise de Regressão , Inibidores Seletivos de Recaptação de Serotonina/administração & dosagem , Caracteres Sexuais
18.
Eur Rev Med Pharmacol Sci ; 26(7): 2422-2430, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35442497

RESUMO

OBJECTIVE: Essence of chicken (EOC), a hot water extract of chicken, is widely consumed in Southeast Asia as a beverage. EOC has an inhibitory effect on the elevation of blood glucose levels and a secretagogue effect on insulin. However, the mechanism by which EOC promotes insulin secretion is unknown. We aimed to verify the postprandial hyperglycemic inhibitory effect and the insulin secretory effect of EOC in healthy adults under appropriate placebo settings. In addition, we aimed to understand the mechanism underlying the insulin secretory effect of EOC. PATIENTS AND METHODS: Thirty-four healthy Japanese adults were fed 68 mL of EOC or control food, followed by 200 g of cooked rice. Blood glucose and plasma insulin levels were measured at 30, 45, 60, 90, and 120 min after the participants ate cooked rice. The trial had a randomized, double-blind, crossover, placebo-controlled design. RESULTS: The ingestion of EOC induced an increase in the maximum blood concentration (Cmax) of insulin and shortened the time required to reach the maximum blood concentration following rice consumption. Ingestion of the test beverage resulted in a significantly higher insulinogenic index than that obtained after ingestion of the control beverage. No side effects were observed in this study. Mechanistic experiments revealed that EOC stimulated significant (p < 0.05) secretion of GLP-1 from NCI-H716 human intestinal L cells at 0.1, 1, and 10 mg/mL. CONCLUSIONS: Consuming EOC when eating rice supports pancreatic function. Daily consumption of EOC could elevate the early-phase insulin response; therefore, it could prevent diabetes in Asians with low insulin secretion.


Assuntos
Glicemia , Galinhas , Animais , Glicemia/análise , Glicemia/metabolismo , Galinhas/metabolismo , Estudos Cross-Over , Método Duplo-Cego , Humanos , Insulina , Secreção de Insulina , Período Pós-Prandial/fisiologia , Água
19.
Phys Rev Lett ; 106(3): 030801, 2011 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-21405263

RESUMO

The Avogadro constant links the atomic and the macroscopic properties of matter. Since the molar Planck constant is well known via the measurement of the Rydberg constant, it is also closely related to the Planck constant. In addition, its accurate determination is of paramount importance for a definition of the kilogram in terms of a fundamental constant. We describe a new approach for its determination by counting the atoms in 1 kg single-crystal spheres, which are highly enriched with the 28Si isotope. It enabled isotope dilution mass spectroscopy to determine the molar mass of the silicon crystal with unprecedented accuracy. The value obtained, NA = 6.022,140,78(18) × 10(23) mol(-1), is the most accurate input datum for a new definition of the kilogram.

20.
Theor Appl Genet ; 123(8): 1433-43, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21861174

RESUMO

Resynthesized Brassica napus cv. Hanakkori (AACC, 2n = 38) was produced by cross-hybridization between B. rapa (AA, 2n = 20) and B. oleracea (CC, 2n = 18) as a new vegetative crop. Many studies have provided evidences for the instability and close relationship between A and C genome in the resynthesized B. napus cultivars. In fact, seed produced to obtain progeny in Hanakkori had unstable morphological characters and generated many off-type plants. In this study, we investigated the pollen fertility, chromosome number, structure, and behavior linked to various Hanakkori phenotypes to define factors of unstable phenotypic expression in the progeny. Hanakkori phenotypes were categorized into five types. The results of pollen fertility, chromosome number, and fluorescence in situ hybridization analysis for somatic mitosis cells indicated that the off-type plants had lower pollen fertility, aberrant chromosome number, and structures with small chromosome fragments. Observation of chromosomes at meiosis showed that the meiotic division in off-type plants led to appreciably higher abnormalities than in on-type plants. However, polyvalent chromosomes were observed frequently in both on- and off-type plants in diplotene stage of meiosis. We assume that the unstable morphological characters in resynthesized progeny were the result of abnormal division in meiosis. It results as important that the plants of normal phenotype, chromosome structure and minimized abnormal meiosis are selected to stabilize progeny.


Assuntos
Brassica napus/crescimento & desenvolvimento , Brassica napus/genética , Cruzamento , Diploide , Verduras/genética , Brassica napus/citologia , Cromossomos de Plantas/genética , Fertilidade/genética , Hibridização in Situ Fluorescente , Meiose/genética , Metáfase/genética , Fenótipo , Pólen/genética
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