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An analytical method for the determination of zilpaterol in livestock products was developed. The sample was stirred with n-hexane and n-hexane saturated acetonitrile, and zilpaterol in the sample was extracted with acetonitrile. The extract was cleaned up on a ODS cartridge column (1 g) and SCX cartridge column (500 mg). The LC separation was carried out using an Inertsil ODS-4 column and linear gradient elution with 0.1%formic acid and acetonitrile containing 0.1% formic acid as mobile phase. Detection of MS was carried out positive ion electrospray ionization mode. Average recoveries (n=5) of zilpaterol from 6 kinds of livestock products fortified at the MRLs (0.01 mg/kg) were 87.0-99.4%, and the relative standard deviations were 2.4-6.3%. The limits of quantitation were 0.01 mg/kg.
Assuntos
Contaminação de Alimentos/análise , Gado , Carne/análise , Compostos de Trimetilsilil/análise , Animais , Cromatografia Líquida , Análise de Alimentos , Espectrometria de Massas em TandemRESUMO
[Purpose] This study aimed to examine the impact of changing the drop vertical jump stance time on kinematic and kinetic parameters by ordering to high jump or quick jump for consistent stance time and a more accurate assessment of anterior cruciate ligament injury risk. [Participants and Methods] The participants were 20 healthy female students. The drop vertical jump was started by instructing the participants to stand on a 30-cm platform with both legs stationary. The task was performed while the participants were instructed to perform high jump or quick jump. [Results] Stance time was significantly shorter with quick jump than with high jump. Quick jump showed significantly higher knee abduction angles at initial contact and peak vertical ground reaction force, and lower hip flexion, knee flexion, and ankle dorsiflexion angles at the lowest point of the center of mass. Quick jump showed a significantly higher peak vertical ground reaction force. The knee abduction moment at initial contact was not significantly different between the 2 conditions. [Conclusion] Quick jump was better than high jump for making stance time consistent, and the differences in kinematic and kinetic characteristics by oral instructions should be considered when using drop vertical jump.
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Packaging of eukaryotic DNA largely depends on histone modifications that affect the accessibility of DNA to transcriptional regulators, thus controlling gene expression. The Polycomb group (PcG) chromatin remodeling complex deposits a methyl group on lysine 27 of histone 3 leading to repressed gene expression. Plants encode homologs of the Enhancer of zeste (E(z)), a component of the PcG complex from Drosophila, one of which is a SET domain protein designated CURLY LEAF (CLF). Although this SET domain protein exhibits a strong correlation with the presence of the H3K27me3 mark in plants, the methyl-transferase activity and specificity of its SET domain have not been directly tested in-vivo. Using the evolutionary early-diverged land plant model species Physcomitrella patens we show that abolishment of a single copy gene PpCLF, as well as an additional member of the PcG complex, FERTILIZATION-INDEPENDENT ENDOSPERM (PpFIE), results in a specific loss of tri-methylation of H3K27. Using site-directed mutagenesis of key residues, we revealed that H3K27 tri-methylation is mediated by the SET domain of the CLF protein. Moreover, the abolishment of H3K27me3 led to enhanced expression of transcription factor genes. This in turn led to the development of fertilization-independent sporophyte-like structures, as observed in PpCLF and PpFIE null mutants. Overall, our results demonstrate the role of PpCLF as a SET protein in tri-methylation of H3K27 in-vivo and the importance of this modification in regulating the expression of transcription factor genes involved in developmental programs of P. patens.
Assuntos
Bryopsida/crescimento & desenvolvimento , Bryopsida/genética , Histona-Lisina N-Metiltransferase/fisiologia , Histonas/metabolismo , Proteínas do Grupo Polycomb/fisiologia , Sequência de Aminoácidos , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Histona Metiltransferases , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/química , Proteínas de Homeodomínio/fisiologia , Lisina/metabolismo , Metilação , Dados de Sequência Molecular , Folhas de Planta/genética , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas , Homologia de Sequência de AminoácidosRESUMO
Leaf primordia are generated at the periphery of the shoot apex, developing into flat symmetric organs with adaxial-abaxial polarity, in which the indeterminate state is repressed. Despite the crucial role of the ASYMMETRIC LEAVES1 (AS1)-AS2 nuclear-protein complex in leaf adaxial-abaxial polarity specification, information on mechanisms controlling their downstream genes has remained elusive. We systematically analyzed transcripts by microarray and chromatin immunoprecipitation assays and performed genetic rescue of as1 and as2 phenotypic abnormalities, which identified a new target gene, ETTIN (ETT)/AUXIN RESPONSE FACTOR3 (ARF3), which encodes an abaxial factor acting downstream of the AS1-AS2 complex. While the AS1-AS2 complex represses ETT by direct binding of AS1 to the ETT promoter, it also indirectly activates miR390- and RDR6-dependent post-transcriptional gene silencing to negatively regulate both ETT and ARF4 activities. Furthermore, AS1-AS2 maintains the status of DNA methylation in the ETT coding region. In agreement, filamentous leaves formed in as1 and as2 plants treated with a DNA methylation inhibitor were rescued by loss of ETT and ARF4 activities. We suggest that negative transcriptional, post-transcriptional and epigenetic regulation of the ARFs by AS1-AS2 is important for stabilizing early leaf partitioning into abaxial and adaxial domains.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Metilação de DNA , Proteínas de Ligação a DNA/metabolismo , Proteínas Nucleares/metabolismo , Folhas de Planta/fisiologia , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Northern Blotting , Proliferação de Células , Imunoprecipitação da Cromatina , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA de Plantas/genética , DNA de Plantas/metabolismo , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Genes de Plantas , Proteínas Nucleares/genética , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição/genética , Transcrição GênicaRESUMO
In this study, the accuracy of using 3D measurements from a 3D image creation application (3DICA) as a potential tool for measuring hoof dimensions in cattle was determined. Fifty distal limbs of cattle obtained from a slaughterhouse were included after the data was trimmed by the functional hoof trimming method. The lengths of six dimensional variables determined by manual measurements served as the true values. Then, the images of these hooves were captured with the 3DICA, and the same variables were determined by the measurement function in the 3DICA. A strong positive correlation was obtained between the 3D and manual measurements for five of the six points, and the mean difference was within 2â¯mm at all six points. However, the limits of agreement varied at three of the six points. In conclusion, compared with manual measurements, the 3D measurements provided approximately equivalent measurements for the hoof dimensions. However, these findings are preliminary, and further investigations are needed.
Assuntos
Casco e Garras , Imageamento Tridimensional , Animais , Bovinos , Casco e Garras/anatomia & histologia , Imageamento Tridimensional/veterinária , Imageamento Tridimensional/métodos , FemininoRESUMO
The control of digital dermatitis (DD) among cattle is crucial; however, effective and environmentally-sound control measures have yet to be identified. From the monitoring data of DD which were recorded during regular hoof trimmings in a farm in Hokkaido, Japan, we detected a decrease in the DD prevalence in a herd where an anaerobic bacterial fermentation enhancer (ABFE) was distributed. The possible effect of ABFE was analyzed using a retrospective repeated cross-sectional design. The prevalence of DD decreased over time in the ABFE-distributed group. Furthermore, a selected regression model indicated the time-dependent enhancement of the decreasing trend. While potential coincidental factors may influence, this study provides a basis for further research on the preventive effect of ABFE against DD.
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Doenças dos Bovinos , Dermatite Digital , Fermentação , Animais , Bovinos , Estudos Retrospectivos , Dermatite Digital/microbiologia , Dermatite Digital/prevenção & controle , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/prevenção & controle , Japão , Estudos Transversais , Bactérias Anaeróbias , Casco e Garras/microbiologiaRESUMO
BACKGROUND: Constipation is a common adverse effect of antipsychotics, but little investigation has been conducted. We aimed to address the factors associated with the initiation of laxative use in the same patients with schizophrenia over a 20-year period. METHODS: We enrolled patients with schizophrenia attending each hospital (n = 14) from April 1, 2021, and retrospectively examined all prescriptions as of April 1, 2016, 2011, 2006, and 2001, every 5 years starting in 2021, for this population. 716 participants with complete data were included in the analysis. The Cochran Q test followed by Bonferroni correction and the Cochran-Armitage trend test were used to determine the differences and trends of the frequency of each laxative. Multivariate logistic regression analysis was performed to assess the factors on the initiation of laxative use over a 20-year period. RESULTS: Of the patients, 25.1% were treated with laxatives in 2001, and 34.1% were treated in 2021. The numbers of patients treated with any laxatives significantly differed over the 20-year period, with a significant increasing trend. In all laxatives, the numbers of patients treated with magnesium oxide, lubiprostone and elobixibat differed with a significant increasing trend. Female sex, age, the total DZP equivalent dose, and the doses of levomepromazine maleate, olanzapine, quetiapine, zotepine, lithium, and carbamazepine in 2021 were significant factors associated with the initiation of laxative use over the 20-year period. CONCLUSIONS: Careful monitoring is needed for patients treated with levomepromazine maleate, olanzapine, quetiapine and zotepine. Optimizing prescriptions according to treatment guidelines could reduce antipsychotic-induced constipation.
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Antipsicóticos , Dibenzotiepinas , Metotrimeprazina/análogos & derivados , Esquizofrenia , Humanos , Feminino , Laxantes/efeitos adversos , Esquizofrenia/tratamento farmacológico , Olanzapina/uso terapêutico , Estudos Retrospectivos , Fumarato de Quetiapina/uso terapêutico , Antipsicóticos/efeitos adversos , Constipação Intestinal/induzido quimicamente , Constipação Intestinal/tratamento farmacológicoRESUMO
Background: Recent pharmacoepidemiology data show an increase in the proportion of patients receiving second-generation antipsychotic (SGA) monotherapy, but no studies have analyzed the same patients over a long period of time. Therefore, in this study, we retrospectively evaluated schizophrenia patients with available data for 20 years to determine whether the drug treatments in the same patients have changed in the past 20 years. Methods: The study began in April 2021 and was conducted in 15 psychiatric hospitals in Japan. Schizophrenia patients treated in the same hospital for 20 years were retrospectively examined for all prescriptions in 2016, 2011, 2006, and 2001 (ie, every 5 years). Results: The mean age of the 716 patients surveyed in 2021 was 61.7 years, with 49.0% being female. The rate of antipsychotic monotherapy use showed a slight increasing trend over the past 20 years; the rate of SGA use showed a marked increasing trend from 28.9% to 70.3% over the past 20 years, while the rate of SGA monotherapy use showed a gradual increasing trend over the past 20 years. The rates of concomitant use of anticholinergics, antidepressants, anxiolytics/sleep medications, and mood stabilizers showed decreasing, flat, flat, and flat trends over the past 20 years, respectively. Conclusion: The results of this study showed a slow but steady substitution of SGAs for first-generation antipsychotics (FGAs) over time, even in the same patients.
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Land plants have distinct developmental programs in haploid (gametophyte) and diploid (sporophyte) generations. Although usually the two programs strictly alternate at fertilization and meiosis, one program can be induced during the other program. In a process called apogamy, cells of the gametophyte other than the egg cell initiate sporophyte development. Here, we report for the moss Physcomitrella patens that apogamy resulted from deletion of the gene orthologous to the Arabidopsis thaliana CURLY LEAF (PpCLF), which encodes a component of polycomb repressive complex 2 (PRC2). In the deletion lines, a gametophytic vegetative cell frequently gave rise to a sporophyte-like body. This body grew indeterminately from an apical cell with the character of a sporophytic pluripotent stem cell but did not form a sporangium. Furthermore, with continued culture, the sporophyte-like body branched. Sporophyte branching is almost unknown among extant bryophytes. When PpCLF was expressed in the deletion lines once the sporophyte-like bodies had formed, pluripotent stem cell activity was arrested and a sporangium-like organ formed. Supported by the observed pattern of PpCLF expression, these results demonstrate that, in the gametophyte, PpCLF represses initiation of a sporophytic pluripotent stem cell and, in the sporophyte, represses that stem cell activity and induces reproductive organ development. In land plants, branching, along with indeterminate apical growth and delayed initiation of spore-bearing reproductive organs, were conspicuous innovations for the evolution of a dominant sporophyte plant body. Our study provides insights into the role of PRC2 gene regulation for sustaining evolutionary innovation in land plants.
Assuntos
Bryopsida/genética , Evolução Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/fisiologia , Bryopsida/citologia , Bryopsida/fisiologia , Clonagem Molecular , Diploide , Deleção de Genes , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Haploidia , Temperatura Alta , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/classificação , Plantas Geneticamente Modificadas , Reprodução/genética , Reprodução/fisiologiaRESUMO
Background: Intraosseous schwannomas are extremely rare and they have not yet been reported to occur in the clivus. We report a schwannoma in the clivus mimicking chordoma and review intraosseous schwannomas of the skull. Case Description: A 62-year-old man presented with gradually worsening hoarseness with dysphagia and atrophy of the left tongue, trapezius muscle, and sternocleidomastoid muscle. Magnetic resonance imaging showed that the tumor was mainly located in the clivus, and a computed tomography (CT) scan revealed an osteolytic lesion with expansion of the clivus and preservation of the bony cortex. Endoscopic endonasal surgery was performed to diagnose and treat symptoms. The tumor was subtotally removed without any complications. The histopathological findings revealed typical schwannoma, which showed Antoni A and Antoni B patterns positive for S100 protein. Based on the preoperative imaging, intraoperative and histopathological findings, the tumor was considered to be an intraosseous schwannoma in the clivus, and no recurrence was observed after 1 year of postoperative follow-up. Conclusion: Even though the intraosseous schwannoma in the clivus is uncommon, it should be considered as a differential diagnosis if an expansive lesion without destruction of the cortical bone is shown on CT as well as iso-hyperintensity on T2-weighted magnetic resonance imaging.
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We investigated the appropriate D-dimer cutoff value for each brain tumor type for acute or subacute deep vein thrombosis (DVT) following transcranial brain tumor surgery.In this single-center retrospective study, a cumulative total of 128 patients who underwent transcranial brain tumor surgery were enrolled and classified into the glioma group, the other intracranial malignant tumor group, and the intracranial benign tumor group. Venous ultrasonography was performed if the D-dimer plasma levels were positive (≥1 µg/mL) before surgery and on postoperative day (POD) 3 or 7.Of the 128 cases, DVT developed in 32 (25.0%). Among those, acute or subacute DVT was diagnosed in 22 cases on POD 3 and in 8 cases on POD 7. Compared with DVT-negative cases on POD 3, acute or subacute DVT-positive cases on POD 3 revealed a significant increase in the D-dimer level in all groups combined and in the benign tumor group but not in the glioma group. With regard to DVT on POD 3 in all groups, the receiver operating characteristic curve for the D-dimer level on POD 3 demonstrated a cutoff value of 3.3 µg/mL (sensitivity [0.636] and specificity [0.750]). However, if this cutoff value was used in practice, eight cases would be false-negative with a minimum D-dimer level of 1.5 µg/mL.The D-dimer cutoff value for acute or subacute DVT on POD 3 could be set to 3.3 µg/mL; however, the setting resulted in several false-negative cases. Practically, 1.5 µg/mL of the D-dimer cutoff value on POD 3 might be appropriate to avoid false-negative results.
Assuntos
Neoplasias Encefálicas , Glioma , Trombose Venosa , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/cirurgia , Produtos de Degradação da Fibrina e do Fibrinogênio , Humanos , Valor Preditivo dos Testes , Estudos Retrospectivos , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/etiologiaRESUMO
Here we describe a case of recurrent ischemic strokes due to fragile innominate artery plaque successfully treated using endovascular stent grafting. An 80-year-old man presented with a history of recurrent strokes that were refractory to medical treatment. Computed tomography and magnetic resonance images of the thorax revealed a gross intramural plaque in the innominate artery. He was successfully treated using endovascular stent grafting. An AFX stent graft device was used to prevent further embolic strokes. The AFX stent graft has a unique endoskeleton design with a thin-walled expanded polytetrafluoroethylene fabric-known as active sealing structure-attached to the implant. Postoperatively, the patient has experienced no recurrent strokes in over 2 years of follow-up. The stent grafting procedure could be an optimal treatment option for treating fragile innominate artery plaques.
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We identified an embryo yellow (eye) mutation in Arabidopsis that leads to the abnormal coloration and morphology of embryos. The eye mutant formed bushy plants, with aberrant organization of the shoot apical meristem (SAM) and unexpanded leaves with irregular phyllotaxy. The epidermal cells of the eye mutant were much smaller than that of the wild-type. Thus, EYE is required for expansion of cells and organs, and for formation of the organized SAM. Hydrophobic layers of epidermal cells were also disrupted, suggesting that EYE might be involved in the generation of the extra-cellular matrix. The mutated gene encoded a protein that is homologous to Cog7, a subunit of the conserved oligomeric Golgi (COG) complex, which is required for the normal morphology and function of the Golgi appratus. The eye mutation caused mislocalization of a Golgi protein. In addition, the size of the Golgi apparatus was also altered. Thus, EYE might be involved in transport or retention of Golgi-localized proteins and in maintenance of Golgi morphology. We propose that some Golgi-localized proteins, distributions of which are controlled by EYE, play important roles in expansion of cells and organs, and in formation of the properly organized SAM in plants.
Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/citologia , Arabidopsis/embriologia , Complexo de Golgi/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/química , Sequência de Aminoácidos , Animais , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Complexo de Golgi/química , Humanos , Meristema , Dados de Sequência Molecular , Mutação , Folhas de Planta/citologia , Alinhamento de SequênciaRESUMO
BACKGROUND: Schwannoma originating from the greater superficial petrosal nerve is an extremely rare type of facial nerve schwannoma located in the middle cranial fossa around the midportion of the petrous bone. Here, we provide the first report of greater superficial petrosal nerve schwannoma presenting with contralateral facial palsy and hemiparesis due to compression of the pyramidal tract by associated intradural peritumoral cyst. CASE DESCRIPTION: A 69-year-old woman presented with a 6-month history of gradually worsening gait unsteadiness. Magnetic resonance imaging demonstrated a well-defined tumor occupying the right middle cranial fossa and extending into the tympanic cavity. Notably, the tumor accompanied a large cyst in the intradural space, resulting in a leftward midline shift. Extradural exploration through thinned periosteal dura mater revealed the tumor within the interdural space. After debulking of most of the tumor in a pull-out, piecemeal fashion, intradural exploration revealed the peritumoral cyst located between the meningeal dura mater and brain parenchyma. Following the disappearance of the mass effect from the tumor, fenestration of the peritumoral cyst, which had been deeper-seated than the tumor, was easily achieved while avoiding excessive retraction of the temporal lobe. Postoperatively, mild left hemiparesis involving the face resolved completely and no new symptoms such as right facial palsy, hearing disturbance, or xerophthalmia developed as postoperative complications. CONCLUSION: The combination of extradural and intradural approaches in the appropriate order is essential for fenestration of an intradural peritumoral cyst along with removal of an interdural tumor.
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Neoplasias dos Nervos Cranianos/cirurgia , Cistos/cirurgia , Gânglio Geniculado , Neurilemoma/cirurgia , Idoso , Neoplasias dos Nervos Cranianos/complicações , Neoplasias dos Nervos Cranianos/diagnóstico por imagem , Cistos/complicações , Cistos/diagnóstico por imagem , Dura-Máter , Feminino , Humanos , Neurilemoma/complicações , Neurilemoma/diagnóstico por imagemRESUMO
Epigenetic modifications, including histone modifications, stabilize cell-specific gene expression programmes to maintain cell identities in both metazoans and land plants1-3. Notwithstanding the existence of these stable cell states, in land plants, stem cells are formed from differentiated cells during post-embryonic development and regeneration4-6, indicating that land plants have an intrinsic ability to regulate epigenetic memory to initiate a new gene regulatory network. However, it is less well understood how epigenetic modifications are locally regulated to influence the specific genes necessary for cellular changes without affecting other genes in a genome. In this study, we found that ectopic induction of the AP2/ERF transcription factor STEMIN1 in leaf cells of the moss Physcomitrella patens decreases a repressive chromatin mark, histone H3 lysine 27 trimethylation (H3K27me3), on its direct target genes before cell division, resulting in the conversion of leaf cells to chloronema apical stem cells. STEMIN1 and its homologues positively regulate the formation of secondary chloronema apical stem cells from chloronema cells during development. Our results suggest that STEMIN1 functions within an intrinsic mechanism underlying local H3K27me3 reprogramming to initiate stem cell formation.
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Bryopsida/crescimento & desenvolvimento , Bryopsida/metabolismo , Proteínas de Plantas/metabolismo , Células-Tronco/metabolismo , Fatores de Transcrição/metabolismo , Bryopsida/genética , Reprogramação Celular , Epigênese Genética , Regulação da Expressão Gênica de Plantas , Histonas/genética , Histonas/metabolismo , Metilação , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Células-Tronco/citologia , Fatores de Transcrição/genéticaRESUMO
We examined mechanoradical formation in the grinding process of commercial tablets using electron spin resonance (ESR). Mechanoradicals were detected in all tested samples (23 types of commercial tablets) when the ball-milling of tablets was conducted under anaerobic conditions and some were fairly stable even in air. Thus the grinding may cause changes in the physicochemical properties of ingredients included in commercial tablets. Because high quality is demanded in pharmaceuticals, these results suggest more caution should be taken in the grinding of commercial tablets in hospitals and pharmacies.
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Química Farmacêutica , Composição de Medicamentos , Prescrições de Medicamentos , Estabilidade de Medicamentos , Radicais Livres/análise , Mecânica , Comprimidos/química , Adjuvantes Farmacêuticos , Fenômenos Químicos , Físico-Química , Espectroscopia de Ressonância de Spin Eletrônica , Tamanho da PartículaRESUMO
The purpose of this study was to identify the roles of non-homologous end-joining (NHEJ) or homologous recombination (HR) pathways in repairing DNA double-strand breaks (DSBs) induced by exposure to high-energy protons and carbon ions (C ions) versus gamma rays in Chinese hamster cells. Two Chinese hamster cell lines, ovary AA8 and lung fibroblast V79, as well as various mutant sublines lacking DNA-PKcs (V3), X-ray repair cross-complementing protein-4 [XRCC4 (XR1), XRCC3 (irs1SF) and XRCC2 (irs1)] were exposed to gamma rays ((137)Cs), protons (200 MeV; 2.2 keV/µm) and C ions (290 MeV; 50 keV/µm). V3 and XR1 cells lack the NHEJ pathway, whereas irs1 and irs1SF cells lack the HR pathway. After each exposure, survival was measured using a clonogenic survival assay, in situ DSB induction was evaluated by immunocytochemical analysis of histone H2AX phosphorylation at serine 139 (γ-H2AX foci) and chromosome aberrations were examined using solid staining. The findings from this study showed that clonogenic survival clearly depended on the NHEJ and HR pathway statuses, and that the DNA-PKcs(-/-) cells (V3) were the most sensitive to all radiation types. While protons and γ rays yielded almost the same biological effects, C-ion exposure greatly enhanced the sensitivity of wild-type and HR-deficient cells. However, no significant enhancement of sensitivity in cell killing was seen after C-ion irradiation of NHEJ deficient cells. Decreases in the number of γ-H2AX foci after irradiation occurred more slowly in the NHEJ deficient cells. In particular, V3 cells had the highest number of residual γ-H2AX foci at 24 h after C-ion irradiation. Chromosomal aberrations were significantly higher in both the NHEJ- and HR-deficient cell lines than in wild-type cell lines in response to all radiation types. Protons and gamma rays induced the same aberration levels in each cell line, whereas C ions introduced higher but not significantly different aberration levels. Our results suggest that the NHEJ pathway plays an important role in repairing DSBs induced by both clinical proton and C-ion beams. Furthermore, in C ions the HR pathway appears to be involved in the repair of DSBs to a greater extent compared to gamma rays and protons.
Assuntos
Dano ao DNA/efeitos da radiação , Reparo do DNA por Junção de Extremidades/efeitos da radiação , Reparo do DNA/efeitos da radiação , Recombinação Genética/efeitos da radiação , Animais , Ciclo Celular/efeitos da radiação , Cricetinae , Cricetulus , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Reparo do DNA por Junção de Extremidades/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Radioterapia com Íons Pesados/efeitos adversos , Humanos , Raios XRESUMO
We show that two Arabidopsis thaliana genes for histone deacetylases (HDACs), HDT1/HD2A and HDT2/HD2B, are required to establish leaf polarity in the presence of mutant ASYMMETRIC LEAVES2 (AS2) or AS1. Treatment of as1 or as2 plants with inhibitors of HDACs resulted in abaxialized filamentous leaves and aberrant distribution of microRNA165 and/or microRNA166 (miR165/166) in leaves. Knockdown mutations of these two HDACs by RNA interference resulted in phenotypes like those observed in the as2 background. Nuclear localization of overproduced AS2 resulted in decreased levels of mature miR165/166 in leaves. This abnormality was abolished by HDAC inhibitors, suggesting that HDACs are required for AS2 action. A loss-of-function mutation in HASTY, encoding a positive regulator of miRNA levels, and a gain-of-function mutation in PHABULOSA, encoding a determinant of adaxialization, suppressed the generation of abaxialized filamentous leaves by inhibition of HDACs in the as1 or as2 background. AS2 and AS1 were colocalized in subnuclear bodies adjacent to the nucleolus where HDT1/HD2A and HDT2/HD2B were also found. Our results suggest that these HDACs and both AS2 and AS1 act independently to control levels and/or patterns of miR165/166 distribution and the development of adaxial-abaxial leaf polarity and that there may be interactions between HDACs and AS2 (AS1) in the generation of those miRNAs.
Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis , Histona Desacetilases/metabolismo , Folhas de Planta , Fatores de Transcrição/metabolismo , Arabidopsis/anatomia & histologia , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Sequência de Bases , Núcleo Celular/metabolismo , Histona Desacetilases/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Dados de Sequência Molecular , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologia , Plantas Geneticamente Modificadas , Interferência de RNA , Fatores de Transcrição/genéticaRESUMO
BACKGROUND: Lung regeneration is an innovative strategy that may cure pulmonary emphysema. The bone marrow (BM) harbors pulmonary stem cells. Hematopoietic cytokine-driven mobilization of BM cells may thus support lung regeneration. OBJECTIVES: The aim of this study was to determine whether systemic administration of macrophage colony-stimulating factor (M-CSF) leads to the regeneration of lungs in a murine model of elastase-induced emphysema. METHODS: C57BL/6J mice were administered elastase intratracheally. Four weeks later, in the absence or presence of elastase treatment, mice were intraperitoneally given either M-CSF or saline on days 1-5 each week for 3 weeks. Lung tissue was harvested 24 h after the last injection. RESULTS: M-CSF administration without prior elastase did not affect the mean linear intercept, surface area, or surface area/lung volume. In contrast, M-CSF administration following elastase injury caused a greater increase in the mean linear intercept and greater decreases in surface area and surface area/lung volume than saline administration following elastase, indicating that M-CSF aggravated emphysema. This aggravation of emphysema was accompanied by accumulation of pulmonary alveolar macrophages (AMs) expressing metalloproteinase (MMP)-9 and MMP-12. M-CSF stimulated AMs to express MMPs in vitro. CONCLUSIONS: These results suggest that M-CSF administration does not support lung regeneration but rather aggravates the lung destruction associated with elastase injury.
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Enfisema/metabolismo , Enfisema/fisiopatologia , Fator Estimulador de Colônias de Macrófagos/farmacologia , Regeneração/fisiologia , Animais , Modelos Animais de Doenças , Enfisema/induzido quimicamente , Enfisema/patologia , Formaldeído , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Elastase Pancreática/farmacologia , Regeneração/efeitos dos fármacos , SuínosRESUMO
We identified a mutation in Arabidopsis that resulted in defective embryos, and we designated this mutation globular arrest1 (gla1). The predicted amino acid sequence encoded by the GLA1 gene is homologous to the amino acid sequences of folylpolyglutamate synthetase (FPGS) and dihydrofolate synthetase (DHFS), which participate in folate biosynthesis. The defect of gla1 in the formation of calli was rescued by the supplement of 5-formyl tetrahydrofolate. These results indicated that GLA1 is involved in the biosynthesis of tetrahydrofolate. The gla1 embryos developed normally in the early stage of development but did not undergo the transition to the heart stage. Thus, the function of the GLA1 gene in embryogenesis appears to be required after the globular stage. However, when the levels of GLA1 transcripts in transgenic plants were increased by introduction of several copies of a GLA1 transgene (GLA6.8), the gla1 embryos that grew on gla1/gla1 GLA6.8/- plants developed as far as the heart to bent-cotyledon stage. This result suggests that the GLA1 function is provided to embryos by maternal tissues until embryos reach the globular stage.