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1.
Ergonomics ; : 1-19, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39086270

RESUMO

Automated vehicles could increase the risk of motion sickness because occupants are not involved in driving and do not watch the road. This paper aimed to investigate the influence of motion predictability on motion sickness in automated vehicles, as better motion anticipation is believed to mitigate motion sickness. In a simulator-based study, twenty participants experienced two driving conditions differing only in turn directions. The repetitive condition featured a repeating turn direction pattern. The non-repetitive condition contained pseudo-randomly ordered turn directions. To mimic an 'eyes-off-the-road' setting and prevent visual motion anticipation, road visuals were omitted. No significant differences in sickness or head motion, a metric for motion anticipation, were found between the conditions. No participant recognised the repeating turn pattern. This suggests no increased motion anticipation in the repetitive condition, possibly due to a reduced ability to recognise a repeating motion pattern in one degree of freedom within more complex motion.


Motion anticipation is believed to mitigate motion sickness. However, in this simulator-based study on automated vehicles, no significant differences in motion anticipation or sickness were observed between repetitive and non-repetitive turn directions. Recognition of a repeating motion pattern in one degree of freedom might be diminished when it is part of more complex motion.

2.
J Exp Bot ; 75(19): 6142-6158, 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-38721634

RESUMO

As sessile organisms, plants enter periods of dormancy in response to environmental stresses to ensure continued growth and reproduction in the future. During dormancy, plant growth is suppressed, adaptive/survival mechanisms are exerted, and stress tolerance increases over a prolonged period until the plants resume their development or reproduction under favorable conditions. In this review, we focus on seed dormancy and bud dormancy, which are critical for adaptation to fluctuating environmental conditions. We provide an overview of the physiological characteristics of both types of dormancy as well as the importance of the phytohormones abscisic acid and gibberellin for establishing and releasing dormancy, respectively. Additionally, recent epigenetic analyses have revealed that dormancy establishment and release are associated with the removal and deposition of histone modifications at the loci of key regulatory genes influencing phytohormone metabolism and signaling, including DELAY OF GERMINATION 1 and DORMANCY-ASSOCIATED MADS-box genes. We discuss our current understanding of the physiological and molecular mechanisms required to establish and release seed dormancy and bud dormancy, while also describing how environmental conditions control dormancy depth, with a focus on the effects of histone modifications.


Assuntos
Código das Histonas , Dormência de Plantas , Reguladores de Crescimento de Plantas , Dormência de Plantas/genética , Dormência de Plantas/fisiologia , Reguladores de Crescimento de Plantas/metabolismo , Giberelinas/metabolismo , Ácido Abscísico/metabolismo , Histonas/metabolismo , Regulação da Expressão Gênica de Plantas
3.
Sensors (Basel) ; 24(7)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38610231

RESUMO

The purpose of this study was to investigate the relationship between clinical outcomes and lateral thrust before and after unicompartmental knee arthroplasty (UKA) using inertial measurement sensor units. Eleven knees were evaluated with gait analysis. The varus angular velocity was used to evaluate lateral thrust. The femorotibial angle (FTA) and hip-knee-ankle angle (HKA) were used to evaluate lower-limb alignment, and the Oxford Knee Score (OKS) and Japanese Orthopaedic Association Score (JOA) were used to evaluate clinical outcomes. The mean pre-UKA peak varus velocity was 37.1 ± 9.8°/s, and that for post-UKA was 28.8 ± 9.1°/s (p = 0.00003), such that instabilities clearly improved. Assuming the definition of lateral thrust is when the varus angular velocity is more than 28.1°/s, 81.8% of patients had lateral thrust preoperatively, but this decreased to 55.6% postoperatively, such that the symptoms and objective findings improved. Both OKS and JOA improved after surgery. In addition, HKA was -7.9° preoperatively and -5.8° postoperatively (p = 0.024), and FTA was 181.4° preoperatively and 178.4° postoperatively (p = 0.012). There was a positive correlation between postoperative JOA and FTA, indicating that changes in postoperative alignment affected clinical outcomes. This study quantitatively evaluated the disappearance of lateral thrust by UKA, and it found that the stability can be achieved by UKA for unstable knees with lateral thrust.


Assuntos
Artroplastia do Joelho , Osteoartrite , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Extremidade Inferior , Articulação do Tornozelo
4.
Nat Commun ; 15(1): 2472, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38503742

RESUMO

Protein arginine methyltransferase 5 (PRMT5) is a well-known epigenetic regulatory enzyme. However, the role of PRMT5-mediated arginine methylation in gene transcription related to cardiac fibrosis is unknown. Here we show that fibroblast-specific deletion of PRMT5 significantly reduces pressure overload-induced cardiac fibrosis and improves cardiac dysfunction in male mice. Both the PRMT5-selective inhibitor EPZ015666 and knockdown of PRMT5 suppress α-smooth muscle actin (α-SMA) expression induced by transforming growth factor-ß (TGF-ß) in cultured cardiac fibroblasts. TGF-ß stimulation promotes the recruitment of the PRMT5/Smad3 complex to the promoter site of α-SMA. It also increases PRMT5-mediated H3R2 symmetric dimethylation, and this increase is inhibited by Smad3 knockdown. TGF-ß stimulation increases H3K4 tri-methylation mediated by the WDR5/MLL1 methyltransferase complex, which recognizes H3R2 dimethylation. Finally, treatment with EPZ015666 significantly improves pressure overload-induced cardiac fibrosis and dysfunction. These findings suggest that PRMT5 regulates TGF-ß/Smad3-dependent fibrotic gene transcription, possibly through histone methylation crosstalk, and plays a critical role in cardiac fibrosis and dysfunction.


Assuntos
Fibroblastos , Disfunção Ventricular Esquerda , Animais , Masculino , Camundongos , Fibroblastos/metabolismo , Fibrose , Coração , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Disfunção Ventricular Esquerda/genética
5.
iScience ; 27(2): 108855, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38318384

RESUMO

The subnuclear distribution of centromeres is cooperatively regulated by condensin II and the linker of nucleoskeleton and cytoskeleton (LINC) complex. However, other nuclear membrane structures and nuclear proteins are probably involved in centromere dynamics and distribution. Here, we focused on the nuclear pore complex (NPC), which is known to regulate gene expression, transcription memory, and chromatin structure in addition to transport between the cytoplasm and nucleoplasm. We report here that some nucleoporins (Nups), including Nup85, Nup133, CG1, Nup93b, and NUA, are involved in centromere scattering in Arabidopsis thaliana. In addition, the centromere dynamics after metaphase in nup mutants were found to be similar to that of the condensin II mutant. Furthermore, both biochemical and genetic approaches showed that the Nups interact with the LINC complex. These results suggest that Nups regulate centromere scattering cooperatively with condensin II and the LINC complex.

6.
Plant J ; 117(6): 1873-1892, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38168757

RESUMO

Global climate change is predicted to result in increased yield losses of agricultural crops caused by environmental conditions. In particular, heat and drought stress are major factors that negatively affect plant development and reproduction, and previous studies have revealed how these stresses induce plant responses at physiological and molecular levels. Here, we provide a comprehensive overview of current knowledge concerning how drought, heat, and combinations of these stress conditions affect the status of plants, including crops, by affecting factors such as stomatal conductance, photosynthetic activity, cellular oxidative conditions, metabolomic profiles, and molecular signaling mechanisms. We further discuss stress-responsive regulatory factors such as transcription factors and signaling factors, which play critical roles in adaptation to both drought and heat stress conditions and potentially function as 'hubs' in drought and/or heat stress responses. Additionally, we present recent findings based on forward genetic approaches that reveal natural variations in agricultural crops that play critical roles in agricultural traits under drought and/or heat conditions. Finally, we provide an overview of the application of decades of study results to actual agricultural fields as a strategy to increase drought and/or heat stress tolerance. This review summarizes our current understanding of plant responses to drought, heat, and combinations of these stress conditions.


Assuntos
Mudança Climática , Secas , Resposta ao Choque Térmico , Produtos Agrícolas/genética , Desenvolvimento Vegetal , Estresse Fisiológico/genética
7.
J Dent Anesth Pain Med ; 23(4): 221-228, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37559665

RESUMO

Background: We assessed the relationship between patient age and remifentanil dosing rate in patients managed under general anesthesia with spontaneous breathing using low-dose remifentanil in sevoflurane. Methods: The participants were patients with an American Society of Anesthesiologists Physical Status of 1 or 2 maintained under general anesthesia with low-dose remifentanil in 1.5-2.0% sevoflurane. The infusion rate of remifentanil was adjusted so that the spontaneous respiratory rate was half the rate prior to the induction of anesthesia, and γH (µg/kg/min) was defined as the infusion rate of remifentanil under stable conditions where the respiratory rate was half the rate prior to the induction of anesthesia for ≥ 15 minutes. The relationship between γH and patient age was analyzed statistically by Spearman's correlation analysis. Results: During dental treatment under general anesthesia using low-dose remifentanil in sevoflurane, a significant correlation was detected between γH and patient age. The regression line of y = -0.00079 x + 0.066 (y-axis; γH, x-axis; patient's age) was provided. The values of γH provide 0.064 µg/kg/min at 2 years and 0.0186 µg/kg/min at 60 years. Therefore, as age increases, the dosing rate exhibits a declining trend. Furthermore, in the dosing rate of remifentanil when the patient's respiratory rate was reduced by half from the preanesthetic respiratory rate, the dosing rate provided was around 0.88 mL/h in all ages if the remifentanil was diluted as 0.1 mg/mL. EtCO2 showed 51.0 ± 5.7 mmHg, and SpO2 was controlled within the normal range by this method. In addition, all dental treatments were performed without major problems, such as awakening and body movement during general anesthesia, and the post-anesthetic recovery process was stable. Conclusion: General anesthesia with spontaneous breathing provides various advantages, and the present method is appropriate for minimally invasive procedures.

8.
Sci Total Environ ; 891: 164384, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37271398

RESUMO

Concentration-discharge relationships are widely used to understand the hydrological processes controlling river water chemistry. This study investigates how hydrological processes affect radionuclide (137Cs and 90Sr) concentrations in surface water in headwater catchments within the Chornobyl Exclusion Zone (ChEZ) in Ukraine. In the flat wetland catchments, the depth of the saturated soil layer changes little throughout the year, but changes in the saturated soil surface area during snowmelt and immediately after rainfall affect water chemistry by changing the opportunities for contact between the surface water and the soil surface. On the other hand, in the slope catchments where there are few wetlands, the water chemistry of river water is governed by changes in the relative contributions of "shallow water" and "deep water" due to changes in the catchment water supply pathways feeding the rivers. In this study, no correlations were observed between dissolved or suspended 137Cs concentrations and either discharge rates or competitive cations, but the solid-liquid ratio of 137Cs was found to be significantly and negatively correlated with water temperature. However, 90Sr concentrations in surface water were found to be strongly related to the water pathways for each of the catchments. Moreover, contact between the surface water and the soil surface and changes in the relative contributions of shallow and deep waters to stream water were correlated with changes in 90Sr concentrations in surface water in wetland and slope catchments, respectively. The study concludes that 90Sr in rivers inside the ChEZ are strongly affected by the water pathways in headwater catchments. Additional studies will be necessary to clarify the details of sorption/desorption reactions.

9.
Sci Total Environ ; 872: 161997, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36739017

RESUMO

In the vicinity of the Chornobyl Nuclear Power Plant (ChNPP), the cooling pond (CP) was an artificially maintained reservoir with water levels regulated to 7 m above the Pripyat River until May 2014, when its pumps stopped operating, resulting in a natural drawdown. To investigate the surface-groundwater system before and after the drawdown, we evaluated the spatial and temporal changes in 90Sr and 137Cs radionuclide concentrations and groundwater levels in the shallow unconfined aquifer near the ChNPP from 2010 to 2019. Additionally, we compared water levels and 90Sr concentrations in Azbuchin Lake, wetlands inside the CP, and the Pripyat River. Using three-year averages before (2011-2013) and after (2017-2019) the drawdown period, we found that 90Sr concentrations significantly increased up to 102 kBq/m3 in the Pripyat River floodplain, north of ChNPP, exceeding the WHO drinking water guideline of 10 kBq/m3. In contrast 137Cs concentrations ranged consistently between 10 and 100 Bq/m3. The groundwater levels decreased over 50 cm at approximately 65 % of shallow monitoring wells and up to 6 m near the CP. The 90Sr concentration increases in some wells at the Pripyat River floodplain were associated with decreased dilution rates from the CP due to the reduced CP leakage, causing changes in groundwater flow direction and decreases in groundwater velocity. From the new finding of this study that the drawdown increased 90Sr concentrations near the floodplain, we estimated the 90Sr flux and contribution to the Pripyat River and the 90Sr contribution did not change significantly after the drawdown. However, radionuclides may accumulate more at the floodplain in the future; therefore, additional monitoring is required to verify 90Sr transport from areas of elevated concentrations and its impact on groundwater in the aquifer.


Assuntos
Acidente Nuclear de Chernobyl , Água Subterrânea , Lagoas , Centrais Nucleares , Radioisótopos de Césio/análise , Água
10.
PNAS Nexus ; 2(2): pgad002, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36845349

RESUMO

During de novo plant organ regeneration, auxin induction mediates the formation of a pluripotent cell mass called callus, which regenerates shoots upon cytokinin induction. However, molecular mechanisms underlying transdifferentiation remain unknown. Here, we showed that the loss of HDA19, a histone deacetylase (HDAC) family gene, suppresses shoot regeneration. Treatment with an HDAC inhibitor revealed that the activity of this gene is essential for shoot regeneration. Further, we identified target genes whose expression was regulated through HDA19-mediated histone deacetylation during shoot induction and found that ENHANCER OF SHOOT REGENERATION 1 and CUP-SHAPED COTYLEDON 2 play important roles in shoot apical meristem formation. Histones at the loci of these genes were hyperacetylated and markedly upregulated in hda19. Transient ESR1 or CUC2 overexpression impaired shoot regeneration, as observed in hda19. Therefore, HDA19 mediates direct histone deacetylation of CUC2 and ESR1 loci to prevent their overexpression at the early stages of shoot regeneration.

11.
Plant Cell ; 35(2): 874-888, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36427255

RESUMO

The endosperm is a nutritive tissue supporting embryo growth in flowering plants. Most commonly, the endosperm initially develops as a coenocyte (multinucleate cell) and then cellularizes. This process of cellularization is frequently disrupted in hybrid seeds generated by crosses between different flowering plant species or plants that differ in ploidy, resulting in embryo arrest and seed lethality. The reason for embryo arrest upon cellularization failure remains unclear. In this study, we show that triploid Arabidopsis thaliana embryos surrounded by uncellularized endosperm mount an osmotic stress response that is connected to increased levels of abscisic acid (ABA) and enhanced ABA responses. Impairing ABA biosynthesis and signaling aggravated triploid seed abortion, while increasing endogenous ABA levels as well as the exogenous application of ABA-induced endosperm cellularization and suppressed embryo growth arrest. Taking these results together, we propose that endosperm cellularization is required to establish dehydration tolerance in the developing embryo, ensuring its survival during seed maturation.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Endosperma/genética , Endosperma/metabolismo , Proteínas de Arabidopsis/metabolismo , Triploidia , Desidratação , Arabidopsis/metabolismo , Sementes/metabolismo , Regulação da Expressão Gênica de Plantas/genética
12.
Curr Opin Plant Biol ; 69: 102264, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35872392

RESUMO

Seed dormancy enables plant seeds to time germination until environmental conditions become favorable for seedling survival. This trait has high adaptive value and is of great agricultural relevance. The endosperm is a reproductive tissue formed after fertilization that in addition to support embryo growth has major roles in establishing seed dormancy. Many genes adopt parent-of-origin specific expression patterns in the endosperm, a phenomenon that has been termed genomic imprinting. Imprinted genes are targeted by epigenetic mechanisms acting before and after fertilization. Recent studies revealed that imprinted genes are involved in establishing seed dormancy, highlighting a new mechanism of parental control over this adaptive trait. Here, we review the regulatory mechanisms establishing genomic imprinting and their effect on seed dormancy.


Assuntos
Impressão Genômica , Dormência de Plantas , Endosperma/genética , Regulação da Expressão Gênica de Plantas/genética , Impressão Genômica/genética , Germinação , Dormência de Plantas/genética , Sementes
13.
J Microsc ; 288(2): 117-129, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-34028848

RESUMO

We improved the three-dimensional spatial resolution of laser scanning transmission microscopy by exploiting the saturated absorption of dye molecules. The saturated absorption is induced by the high-intensity light irradiation and localises the signal within the centre of the focal spot. Our numerical calculation indicates that the spatial resolution in transmission imaging is significantly improved for both lateral and axial directions using nonlinear transmitted signals induced by saturated absorption. We experimentally demonstrated the improvement of the three-dimensional resolution by observing fine structures of stained rat kidney tissues, which were not able to be visualised by conventional laser scanning transmission microscopy.


Confocal laser scanning microscopy is a powerful technique for three-dimensional imaging to study structures in a specimen. The use of confocal pinhole provides three-dimensional spatial resolution in various types of optical microscopes, such as fluorescence, reflection and scattering. However, in transmission microscopy, the confocal pinhole cannot provide the same effect because the spatial information on the optical axial is not transferred in the imaging system. Therefore, the three-dimensional distribution of light absorbers cannot be observed by laser scanning transmission microscopy. In this paper, we propose the use of saturated absorption to image the three-dimensional distribution of light absorbers in a sample by laser scanning transmission microscopy. The saturated absorption is induced by the high-intensity light irradiation and occurs prominently at the centre of a focal spot. The information of the saturated absorption signal within the focal spot is transferred to the transmitted light, providing the capability of optical sectioning in transmission imaging. In our research, we theoretically and experimentally confirmed that light absorption by dye molecules is saturable at the high illumination intensity, and the saturated absorption signal can be extracted by harmonic demodulation. We obtained the images of a stained rat kidney tissue by selectively detecting the nonlinear transmission signals induced by saturable absorption of the dye molecules. We confirmed the high depth discrimination capability of our technique clearly visualised the fine structures in the specimen that cannot be observed by a conventional laser scanning absorption microscope.


Assuntos
Lasers , Animais , Ratos , Fenômenos Químicos , Microscopia Confocal
15.
Int Heart J ; 62(6): 1379-1386, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34853228

RESUMO

Clinical studies have indicated that 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, also known as statins, can potentially inhibit chronic heart failure. In the Stat-LVDF study, a difference was noted in terms of the effect of lipophilic pitavastatin (PTV) and hydrophilic rosuvastatin (RSV) on plasma BNP, suggesting that statin lipophilicity and pharmacokinetics change the pleiotropic effect on heart failure in humans. Therefore, we assessed the beneficial effects of PTV on hypertrophy in cardiac myocytes compared with RSV at clinically used doses. Cultured cardiomyocytes were stimulated with 30 µM phenylephrine (PE) in the presence of PTV (250 nM) or RSV (50 nM). These doses were calculated based on the maximum blood concentration of statins used in clinical situations in Japan. The results showed that PTV, but not RSV, significantly inhibits the PE-induced increase in cell size and leucine incorporation without causing cell toxicity. In addition, PTV significantly suppressed PE-induced mRNA expression of hypertrophic response genes. PE-induced ERK phosphorylation was inhibited by PTV, but not by RSV. Furthermore, PTV significantly suppressed the angiotensin-II-induced proline incorporation in primary cultured cardiac fibroblasts. In conclusion, a clinical dose of PTV was noted to directly inhibit cardiomyocyte hypertrophy and cardiac fibrosis, suggesting that lipophilic PTV can be a potential drug candidate against chronic heart failure.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Miócitos Cardíacos/efeitos dos fármacos , Quinolinas/administração & dosagem , Rosuvastatina Cálcica/administração & dosagem , Actinas/genética , Actinas/metabolismo , Animais , Fator Natriurético Atrial/genética , Fator Natriurético Atrial/metabolismo , Células Cultivadas , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Expressão Gênica , Hipertrofia , Leucina/metabolismo , Peptídeo Natriurético Encefálico/genética , Peptídeo Natriurético Encefálico/metabolismo , Fosforilação/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley
16.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 6086-6089, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34892505

RESUMO

In the study of an electroencephalography (EEG)-based brain computer interface (BCI) using the P300, there have been many reports on computer algorithms that identify the target intended by a user from multiple candidates. However, because the P300 amplitude depends on the subject's condition and is attenuated by physical and mental factors, such as fatigue and motivation, the performance of the BCI is low. Therefore, we aim to improve performance by introducing a feedback mechanism that provides the user with an evaluation calculated by the computer during EEG measurement. In this study, we conducted an experiment in which the user input one character from four characters on the display. By changing the character size according to the evaluation score calculated by the computer, the computer's current evaluation was fed back to the user. This is expected to change the consciousness of the user to enable them to execute a task by knowing the evaluation; that is, if the evaluation is high, the user needs to maintain the current state, and if the evaluation is low, a behavioral change, such as increasing attention, is required to improve the evaluation.As a result of comparing 10 subjects with and without feedback, accuracy improved for seven subjects that were given feedback.


Assuntos
Interfaces Cérebro-Computador , Algoritmos , Computadores , Eletroencefalografia , Retroalimentação Sensorial , Humanos
17.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 6090-6093, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34892506

RESUMO

In clinical examination, event-related potentials (ERPs) are estimated by averaging across multiple responses, which suppresses background EEG. However, acquiring the number of responses needed for this process is time consuming. We therefore propose a method for shortening the measurement time using weighted-average processing based on the output of deep learning. Using P300 as a representative component, here we focused on the shape of the ERP and evaluated whether our method emphasizes the P300 peak amplitude more than conventional averaging, while still maintaining the waveform shape and the P300 peak latency. Thus, using either CNN or EEGNet, the correlation coefficient reflecting the waveform shape, the peak P300 amplitude, and the peak latency were evaluated and compared with the same factors obtained from conventional waveform averaging. Additionally, the degree of background EEG suppression provided by our method was evaluated using the root mean square of the pre-stimulation waveform, and the number of fewer responses required for averaging (i.e., the reduction in measurement time) was calculated.The results showed that compared with P300 values obtained through conventional averaging, our method allowed for the same shape and response latency, but with a higher amplitude, while requiring a smaller number of responses. Our method showed that by using EEGNet, measurement time could be reduced by 13.7%. This corresponds to approximately a 40-second reduction for every 5 minutes of measurement time.


Assuntos
Aprendizado Profundo , Eletroencefalografia , Potenciais Evocados , Tempo de Reação
18.
Elife ; 102021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34427186

RESUMO

Polycomb Repressive Complex 2 (PRC2)-mediated trimethylation of histone H3 on lysine 27 (H3K27me3) and methylation of histone 3 on lysine 9 (H3K9me) are two repressive epigenetic modifications that are typically localized in distinct regions of the genome. For reasons unknown, however, they co-occur in some organisms and special tissue types. In this study, we show that maternal alleles marked by H3K27me3 in the Arabidopsis endosperm were targeted by the H3K27me3 demethylase REF6 and became activated during germination. In contrast, maternal alleles marked by H3K27me3, H3K9me2, and CHG methylation (CHGm) are likely to be protected from REF6 targeting and remained silenced. Our study unveils that combinations of different repressive epigenetic modifications time a key adaptive trait by modulating access of REF6.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Endosperma/genética , Epigênese Genética , Dormência de Plantas
19.
Ther Clin Risk Manag ; 17: 365-369, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33911872

RESUMO

In general dental conditions such as dental caries and periodontal disease, a combination of adverse conditions can cause potentially life-threatening periodontal abscess. We treated a patient in whom an oral infection developed into septic shock, resulting in patient death. A 78-year-old woman experienced spontaneous pain around a moving tooth. Pus discharge was observed, the area was sterilized, and an analgesic was prescribed. A few days later, the swelling spread to the buccal region leading to difficulty while eating. Upon systemic status and blood examination at our dental hospital, depressed consciousness due to dehydration and septic shock were suspected. Oxygenation and infusion of acetate linger with antibiotics were immediately performed. Furthermore, a blood examination revealed malnutrition and a severe infection; therefore, the patient was transferred to a nearby general hospital. However, the patient died the next day because of advanced disseminated intravascular coagulation and multiple organ failure. When an oral infection is suspected in an elderly patient, antibiotics should be quickly administered, the patient's local and systemic state should be confirmed, and sterilization should be performed daily. If no improvement is observed, medical attention should be quickly sought.

20.
Plant Physiol ; 185(4): 2003-2021, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33566101

RESUMO

The Polycomb Repressive Complex 2 (PRC2) is well-known for its role in controlling developmental transitions by suppressing the premature expression of key developmental regulators. Previous work revealed that PRC2 also controls the onset of senescence, a form of developmental programmed cell death (PCD) in plants. Whether the induction of PCD in response to stress is similarly suppressed by the PRC2 remained largely unknown. In this study, we explored whether PCD triggered in response to immunity- and disease-promoting pathogen effectors is associated with changes in the distribution of the PRC2-mediated histone H3 lysine 27 trimethylation (H3K27me3) modification in Arabidopsis thaliana. We furthermore tested the distribution of the heterochromatic histone mark H3K9me2, which is established, to a large extent, by the H3K9 methyltransferase KRYPTONITE, and occupies chromatin regions generally not targeted by PRC2. We report that effector-induced PCD caused major changes in the distribution of both repressive epigenetic modifications and that both modifications have a regulatory role and impact on the onset of PCD during pathogen infection. Our work highlights that the transition to pathogen-induced PCD is epigenetically controlled, revealing striking similarities to developmental PCD.


Assuntos
Apoptose/fisiologia , Arabidopsis/genética , Arabidopsis/microbiologia , Arabidopsis/fisiologia , Interações Hospedeiro-Patógeno/fisiologia , Complexo Repressor Polycomb 2/genética , Complexo Repressor Polycomb 2/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Interações Hospedeiro-Patógeno/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia
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