Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 78
Filtrar
1.
Cureus ; 16(2): e53803, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38465079

RESUMO

BACKGROUND: The biomechanical effect of distal tibial oblique osteotomy (DTOO) on osteoarthritic ankles has not been investigated. Using finite element (FE) models, we aimed to elucidate the effect of DTOO on the ankle contact pressure (CP) distribution. METHODS: This study included two patients with ankle osteoarthritis who underwent DTOO and one asymptomatic control. Patient-specific FE models were reconstructed by matching standing radiographs with supine computed tomography scans. The joint contact area (CA) and maximum CP on the articular surface of the talus were calculated before and after DTOO and compared with those of the control. RESULTS: In the control, the CA was 584 mm2 and the maximum CP was 2.6 MPa. In case 1, the CA increased by 125% from 166 mm2 preoperatively to 375 mm2 postoperatively, accompanied by a 36% decrease in the maximum CP from 9.8 MPa to 6.3 MPa. Similarly, in case 2, the CA increased by 46% from 301 mm2 to 439 mm2, accompanied by a 27% decrease in the maximum CP from 6.7 MPa to 4.9 MPa. CONCLUSIONS: This study suggests DTOO improves the biomechanics of the ankle, but not sufficiently compared to the control. This analytical approach may enhance understanding of ankle pathophysiology and assist in the design of the ideal corrective osteotomy.

2.
Med Dosim ; 48(4): 261-266, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37455221

RESUMO

We modeled the Qfix Encompass™ immobilization system and further verified the calculated dose distribution of the AcurosXB (AXB) dose calculation algorithm using SRS MapCHECKⓇ (SRSMC) in the HyperArc™ (HA) clinical plan. An Encompass system with a StereoPHAN™ QA phantom was scanned by SOMATOM go.Sim and imported to an Eclipse™ treatment planning system to create a treatment plan for Encompass modeling. The Encompass modeling was performed in the StereoPHAN with a pinpoint ion chamber for 6 MV and 6 MV flattening filter free (6 MV FFF), and 2 × 2 cm2, 4 × 4 cm2, and 6 × 6 cm2 irradiation field sizes. The dose calculation algorithm used was AXB ver. 15.5 with a 1.0 mm calculation grid size. The Hounsfield unit (HU) values of the Encompass modeling were set to 400, -100, -200, and -300 for Encompass, and -400, -600, -700, and -800 for the Encompass base. We evaluated the dose distribution after Encompass modeling by SRSMC using gamma analysis in 12 patients. We adopted HU values of -200 for Encompass, -800 for Encompass base for 6 MV, and -200 for Encompass and -700 for Encompass. Base for 6 MV FFF was adopted as the HU values for the Encompass modeling based on the measurement results. The proposed Encompass modeling resulted in a mean pass rate evaluation >98% for both 6 MV and 6 MV FFF when the 1%/1 mm criterion was used, demonstrating that the proposed HU value can be adopted to calculate more accurate dose distributions.


Assuntos
Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Humanos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Algoritmos , Imagens de Fantasmas , Radioterapia de Intensidade Modulada/métodos
3.
J Infect Chemother ; 29(8): 800-802, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37075979

RESUMO

Leptospirosis, a zoonotic disease characterized by a spectrum of influenza-like symptoms, can manifest as severe cases so called Weil's disease. Early diagnosis and treatment are crucial to avoid the potentially fatal course of the disease. Within 24 hours of the initial administration of antibiotics, patients may experience the Jarisch-Herxheimer reaction (JHR), characterized by chills, fever, hypotension, and impaired consciousness. The Okinawa Prefecture, where our hospital is situated, boasts the highest incidence rate of leptospirosis among all regions in Japan. This reports our encounter with the initial leptospirosis case after a period of 16 years within the Okinawa Prefecture. This case exhibited JHR and required the utilization of noradrenaline (NA). Despite evidence indicating that JHR does not correlate with mortality, we contend that diagnosis of Weil's disease necessitates admission to an intensive care unit (ICU) and vigilant monitoring for JHR, as it may result in impairment of general condition and fatal outcome, as observed in our case.


Assuntos
Leptospirose , Doença de Weil , Humanos , Doença de Weil/tratamento farmacológico , Leptospirose/diagnóstico , Leptospirose/tratamento farmacológico , Antibacterianos/efeitos adversos , Norepinefrina/uso terapêutico , Japão/epidemiologia
4.
J Exp Bot ; 74(6): 1758-1769, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36629282

RESUMO

Plants recognize the direction of a light source and exhibit phototropic responses. Physiological studies have predicted that differences in the light intensity received by the cells on the irradiated and shaded sides of a coleoptile or hypocotyl cause differences in the amounts of photoproduct. This hypothetical photoproduct appears to regulate a signaling pathway that controls cell elongation in which cells under lower light intensity elongate more than those under higher light intensity. This results in a bending growth toward a light source and has been proposed as the photoproduct-gradient model of phototropism. In this review, we summarize recent findings on the photosensory adaptation mechanisms involving a blue-light photoreceptor, phototropin1 (phot1), ROOT PHOTOTROPISM2, NONPHOTOTROPIC HYPOCOTYL3 (NPH3), and another photoreceptor family, the phytochromes. The current evidence demonstrates that, in addition to the transition of the phot1-NPH3 photoreceptor complexes to their active state, the presence of a certain population of the phot1-NPH3 complexes showing a steady state, even in a light environment, is essential for recognition of the light source direction in phototropism. This is consistent with the photoproduct-gradient model, and a dissociation state of the phot1-NPH3 complex would be considered an entity of the hypothetical photoproduct in this model.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fototropismo/fisiologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Hipocótilo/metabolismo , Luz
5.
Glob Health Med ; 4(3): 201-203, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35855063

RESUMO

Numerous difficulties unique to remote island regions exist in the fight against coronavirus disease 2019 (COVID-19). For example, in the Yaeyama Medical Region (Okinawa, Japan), there are only clinics without beds on constituent islands. As medical resources are limited on remote islands, a single outbreak can put the entire medical system at risk. In addition, local governments need to maintain economic support while taking measures to contain outbreaks. For future COVID-19 countermeasures, it is essential to establish a response team in the regional hospital to conduct on-site epidemiological surveys as early as possible in a pandemic. In addition, distributing effective oral antivirals to remote islands may reduce the spread of infection and the number of severe cases requiring off-region transfer.

6.
Medicina (Kaunas) ; 58(4)2022 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-35454347

RESUMO

The concept of minimally invasive spine therapy (MIST) has been proposed as a treatment strategy to reduce the need for overall patient care, including not only minimally invasive spine surgery (MISS) but also conservative treatment and rehabilitation. To maximize the effectiveness of patient care in spine surgery, the educational needs of medical students, residents, and patient rehabilitation can be enhanced by digital transformation (DX), including virtual reality (VR), augmented reality (AR), mixed reality (MR), and extended reality (XR), three-dimensional (3D) medical images and holograms; wearable sensors, high-performance video cameras, fifth-generation wireless system (5G) and wireless fidelity (Wi-Fi), artificial intelligence, and head-mounted displays (HMDs). Furthermore, to comply with the guidelines for social distancing due to the unexpected COVID-19 pandemic, the use of DX to maintain healthcare and education is becoming more innovative than ever before. In medical education, with the evolution of science and technology, it has become mandatory to provide a highly interactive educational environment and experience using DX technology for residents and medical students, known as digital natives. This study describes an approach to pre- and intraoperative medical education and postoperative rehabilitation using DX in the field of spine surgery that was implemented during the COVID-19 pandemic and will be utilized thereafter.


Assuntos
Realidade Aumentada , COVID-19 , Educação Médica , Inteligência Artificial , Educação Médica/métodos , Humanos , Pandemias
7.
Plant Signal Behav ; 17(1): 2027138, 2022 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-35068333

RESUMO

The blue light photoreceptors, phototropin 1 (phot1) and phot2, and their signal transducer, NONPHOTOTROPIC HYPOCOTYL3 (NPH3), are activators of the phototropic responses of Arabidopsis hypocotyls. In a recent study, we reported that the control of NPH3 phosphorylation at serine 7 (S7: or S5), S213, S223, S237, S467, S474 (or S476), and S722 (or S723) contributes to the photosensory adaptation of phot1 signaling during the phototropic response. Phosphomimetic NPH3SE mutant and unphosphorylatable NPH3SA mutant on those serine residues function efficiently under blue light conditions at fluence rates of 10-5 µmol m-2 s-1 and 10-3 µmol m-2 s-1 or more, respectively. We here demonstrate that phosphomimetic NPH3SE, but not unphosphorylatable NPH3SA, promotes phot2-dependent phototropism under blue light condition at 100 µmol m-2 s-1. This result suggests that phot1 negatively controls phot2 signaling through the dephosphorylation of NPH3 at those residues and that the hyperactivation of phot1- and phot2-NPH3 complexes does not occur at the same time under high intensity blue light. We hypothesize that the dephosphorylation of NPH3 on those serine residues suppresses both phot1 and phot2 signaling, which results in different impacts on phot1- and phot2-dependent hypocotyl phototropism due to the differences in the photosensitivity and activation levels of phot1 and phot2.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Hipocótilo/metabolismo , Luz , Fosfoproteínas/metabolismo , Fosforilação , Fototropinas/metabolismo , Fototropismo/genética , Serina
8.
Plant Physiol ; 187(2): 981-995, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34608954

RESUMO

Photosensory adaptation, which can be classified as sensor or effector adaptation, optimizes the light sensing of living organisms by tuning their sensitivity to changing light conditions. During the phototropic response in Arabidopsis (Arabidopsis thaliana), the light-dependent expression controls of blue-light (BL) photoreceptor phototropin 1 (phot1) and its modulator ROOT PHOTOTROPISM2 (RPT2) are known as the molecular mechanisms underlying sensor adaptation. However, little is known about effector adaption in plant phototropism. Here, we show that control of the phosphorylation status of NONPHOTOTROPIC HYPOCOTYL3 (NPH3) leads to effector adaptation in hypocotyl phototropism. We generated unphosphorable and phosphomimetic NPH3 proteins on seven phosphorylation sites in the etiolated seedlings of Arabidopsis. Unphosphorable NPH3 showed a shortening of its retention time in the cytosol and caused an inability to adapt to very low fluence rates of BL (∼10-5 µmol m-2 s-1) during the phototropic response. In contrast, the phosphomimetic NPH3 proteins had a lengthened retention time in the cytosol and could not enable the adaptation to BL at fluence rates of 10-3 µmol m-2 s-1 or more. Our results indicate that the activation level of phot1 and the corresponding phosphorylation level of NPH3 determine the dissociation rate and the reassociation rate of NPH3 on the plasma membrane, respectively. These mechanisms may moderately maintain the active state of phot1 signaling across a broad range of BL intensities and contribute to the photosensory adaptation of phot1 signaling during the phototropic response in hypocotyls.


Assuntos
Arabidopsis , Fototropismo , Arabidopsis/genética , Arabidopsis/fisiologia , Fosforilação , Fototropismo/fisiologia , Transdução de Sinais
9.
Plant Physiol ; 186(4): 2037-2050, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34618101

RESUMO

Root hair cells form the primary interface of plants with the soil environment, playing key roles in nutrient uptake and plant defense. In legumes, they are typically the first cells to become infected by nitrogen-fixing soil bacteria during root nodule symbiosis. Here, we report a role for the CELLULOSE SYNTHASE-LIKE D1 (CSLD1) gene in root hair development in the legume species Lotus japonicus. CSLD1 belongs to the cellulose synthase protein family that includes cellulose synthases and cellulose synthase-like proteins, the latter thought to be involved in the biosynthesis of hemicellulose. We describe 11 Ljcsld1 mutant alleles that impose either short (Ljcsld1-1) or variable (Ljcsld1-2 to 11) root hair length phenotypes. Examination of Ljcsld1-1 and one variable-length root hair mutant, Ljcsld1-6, revealed increased root hair cell wall thickness, which in Ljcsld1-1 was significantly more pronounced and also associated with a strong defect in root nodule symbiosis. Lotus japonicus plants heterozygous for Ljcsld1-1 exhibited intermediate root hair lengths, suggesting incomplete dominance. Intragenic complementation was observed between alleles with mutations in different CSLD1 domains, suggesting CSLD1 function is modular and that the protein may operate as a homodimer or multimer during root hair development.


Assuntos
Glucosiltransferases/genética , Lotus/genética , Proteínas de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Glucosiltransferases/metabolismo , Lotus/enzimologia , Lotus/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética
10.
Rinsho Shinkeigaku ; 61(4): 247-252, 2021 Apr 21.
Artigo em Japonês | MEDLINE | ID: mdl-33762498

RESUMO

We experienced 3 adult patients with intractable focal epilepsy treated by levetiracetam (LEV) as polytherapy, who showed paradoxical effect (PE). Starting dose of LEV was small (62.5, 250 mg/day) and we gradually increased by less than 250 mg/day, every more than 2 weeks. Within 6 months after LEV was added, LEV of 750 to 1,000 mg/day brought reduction of seizure frequency. Serum concentration of LEV was 13.3 and 14.0 µg/ml. In order to obtain better seizure control, LEV was increased up to 1,000-2,500 mg/day (19.3-35.0 µg/ml) within one year, and they developed PE. They all showed increased habitual seizures, occurring in cluster. Once dose of LEV deceased down to what produced the maximum seizure suppression, all of the patients regained the better seizure control. It is most likely that at least in some patients like present 3 cases, PE of LEV may express U curve association between dose and effect and that it was only delineated by slow titration.


Assuntos
Anticonvulsivantes/administração & dosagem , Levetiracetam/administração & dosagem , Convulsões/prevenção & controle , Adulto , Anticonvulsivantes/efeitos adversos , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Eletroencefalografia , Feminino , Humanos , Levetiracetam/efeitos adversos , Imageamento por Ressonância Magnética , Masculino , Convulsões/diagnóstico , Resultado do Tratamento
11.
J Dermatol Sci ; 101(1): 4-13, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33168399

RESUMO

BACKGROUND: Human organic cation transporter 3 (OCT3,SLC22A3) mediates the uptake of many important endogenous substances and basic drugs, and has been identified as one of the transporters that are highly expressed in human skin. However, the mechanisms responsible for variability in mRNA expression, and the role of SLC22A3 in human skin is not clear. OBJECTIVE: We examined the effects of the single nucleotide polymorphisms ofSLC22A3 on the variability in SLC22A3 expression and sebum levels in humans. METHODS: Immunostaining of OCT3 in human skin was performed. We analyzed the association of promoter variants with the SLC22A3 mRNA expression levels in human skins. Luciferase, knockdown, chromatin immunoprecipitation (ChIP), electrophoretic mobility shift assay were employed to investigate transcriptional regulation of SLC22A3 expression. Effects of the identified variant on sebum levels were evaluated in healthy volunteers. RESULTS: Immunohistochemistry revealed marked expressions of OCT3 in the basal epidermis, sebaceous glands, hair follicles, and sweat glands of human skin. SLC22A3 mRNA levels were significantly lower in skin samples with homozygotes for -1603A/A than in those for -1603 G/G. The analysis of p53 binding to -1603 G > A in the promoter ofSLC22A3 suggested that -1603 G > A down-regulates SLC22A3 gene expression by decreased p53 binding in the vicinity of the -1603 site. In humans, squalene levels in samples from the back at the baseline were significantly lower in homozygotes for -1603A/A than in those for -1603 G/G. CONCLUSION: These results suggest that the genetic variant contributes to the variability of expression and activities of OCT3 in human skin.


Assuntos
Fator 3 de Transcrição de Octâmero/metabolismo , Proteínas de Transporte de Cátions Orgânicos/genética , Sebo/metabolismo , Fenômenos Fisiológicos da Pele/genética , Pele/metabolismo , Região 5'-Flanqueadora/genética , Adulto , Feminino , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Células HaCaT , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas/genética , Ativação Transcricional , Proteína Supressora de Tumor p53/metabolismo , Adulto Jovem
12.
Int J Surg Case Rep ; 76: 338-340, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33074132

RESUMO

INTRODUCTION: Traumatic boutonniere deformities of the fingers are well documented unlike those of the lesser toes. With few existing reports on boutonniere deformities of the lesser toes, the related pathology and treatment guidelines remain unclear. PRESENTATION OF CASE: We present a case of traumatic boutonniere deformity of the second toe caused by sumo wrestling in a 23-year-old man. A flexion deformity of the proximal interphalangeal joint and hyperextension of the distal interphalangeal joint of the right second toe were observed, including a torn central slip and plantarly displaced lateral bands during surgery. Surgical repair of the extensor mechanism and temporary pinning led to good clinical results. DISCUSSION: Acute traumatic boutonniere deformity of the interphalangeal joint of the lesser toe is very rare. The mechanism of boutonniere deformity in this case is thought to be due to forced passive flexion exerted on an actively extended PIP joint, which is similar to that seen in fingers. CONCLUSION: We describe the pathophysiology of a case of boutonniere deformity of the lesser toe and suggest the effectiveness of surgical treatment.

13.
Asia Ocean J Nucl Med Biol ; 8(2): 102-108, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32714997

RESUMO

OBJECTIVES: L-4-borono-2-18F-fluoro-phenylalanine (L-[18F]FBPA), a substrate of L-type amino acid transporter 1 (LAT1), is a tumor-specific probe used in positron emission tomography (PET). On the other hand, it has not been examined whether another isomer D-[18F]FBPA accumulates specifically in the tumor. Here, we compared the accumulation of D-[18F]FBPA in C6 glioma and inflammation to evaluate the performance of D-[18F]FBPA as a tumor-specific probe. METHODS: HEK293-LAT1 and HEK293-LAT2 cells were tested for [14C]-leucine or [14C]-alanine transport, and IC50 values of L- and D-FBPA were evaluated in both cell types. PET was conducted in rat xenograft model of C6 glioma with LAT1 expression and model of turpentine oil-induced subcutaneous inflammation (n=10 for both models). The concentrations of D-[18F]FBPA were compared between glioma and inflammatory lesion using standardized uptake value (SUV). RESULTS: In contrast to L-FBPA, which inhibited substrate uptake in both HEK293-LAT1 and -LAT2 cells, D-FBPA showed no inhibitory effect on both cells, suggesting low transporter selectivity of D-[18F]FBPA against LAT1 and LAT2. Static PET analysis showed low accumulation of D-[18F]FBPA in C6 glioma and inflammatory lesion (SUVmax=0.80±0.16, 0.56±0.09, respectively). Although there was a statistical difference in SUVmax between these tissues, it was difficult to distinguish glioma from inflammation on the PET image due to its low uptake level. Therefore, it was suggested that D-[18F]FBPA is not a suitable tumor-specific probe for oncology PET in contrast to L-[18F]FBPA. CONCLUSION: This study demonstrated that D-[18F]FBPA is not a LAT1-specific PET probe and shows low uptake in C6 glioma, indicating its unsuitability as a tumor diagnosis PET probe.

14.
Plant Cell ; 32(6): 2004-2019, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32213636

RESUMO

The Arabidopsis (Arabidopsis thaliana) blue light photoreceptor phototropin1 (phot1) is a blue light-activated Ser/Thr protein kinase that mediates various light responses, including phototropism. The function of phot1 in hypocotyl phototropism is dependent on the light induction of ROOT PHOTOTROPISM2 (RPT2) proteins within a broad range of blue light intensities. It is not yet known however how RPT2 contributes to the photosensory adaptation of phot1 to high intensity blue light and the phototropic responses under bright light conditions. We show that RPT2 suppresses the activity of phot1 and demonstrate that RPT2 binds to the PHOT1 light, oxygen or voltage sensing1 (LOV1) domain that is required for its high photosensitivity. Our biochemical analyses revealed that RPT2 inhibits autophosphorylation of phot1, suggesting that it suppresses the photosensitivity and/or kinase activity of phot1 through the inhibition of LOV1 function. We found that RPT2 proteins are degraded via a ubiquitin-proteasome pathway when phot1 is inactive and are stabilized under blue light in a phot1-dependent manner. We propose that RPT2 is a molecular rheostat that maintains a moderate activation level of phot1 under any light intensity conditions.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas Serina-Treonina Quinases/genética
15.
Ophthalmol Ther ; 8(4): 511-517, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31372937

RESUMO

INTRODUCTION: Azithromycin demonstrates high tissue distribution and prolonged elimination half-life. In this study, we monitored the pharmacokinetics of a single ophthalmic administration of 1% azithromycin ophthalmic solution containing polycarbophil in the extraocular tissues, including the eyelid, and compared it with that of two commercial ophthalmic products, 1.5% levofloxacin ophthalmic solution and 0.3% ofloxacin ophthalmic ointment. METHODS: Rabbits were treated with either a single topical administration of 1% azithromycin ophthalmic solution, 1.5% levofloxacin ophthalmic solution, or 0.3% ofloxacin ophthalmic ointment. The eyelid, conjunctiva, and cornea were collected at 0.25, 0.5, 1, 2, 4, 8, and 24 h post-administration. Tissue samples were pretreated for drug concentration measurements by ultra-performance liquid chromatography-tandem mass spectrometry. Pharmacokinetic parameters were determined by non-compartmental analysis. RESULTS: Azithromycin was rapidly absorbed, and its levels remained near the observed maximum concentrations for up to 24 h post-administration in all tissue. In contrast, extraocular tissue concentrations of levofloxacin and ofloxacin decreased with time. The maximum concentrations of azithromycin, levofloxacin, and ofloxacin were 35.6, 34.1, and 55.1 µg/g in the eyelid, 44.2, 46.8, and 20.4 µg/g in the conjunctiva, and 79.9, 18.0, and 2.21 µg/g in the cornea, respectively. The values of the area under the curve from 0 to 24 h after administration of azithromycin, levofloxacin, and ofloxacin were 602, 58.5, and 267 µg·h/g in the eyelid, 837, 43.2, and 51.9 µg·h/g in the conjunctiva, and 1250, 26.4, and 5.46 µg h/g in the cornea, respectively. CONCLUSION: The drug concentrations of azithromycin and levofloxacin were relatively comparable among the extraocular tissues following topical administration of the respective ophthalmic solutions, whereas the concentrations of ofloxacin varied following dosing of its ophthalmic ointment. The slow elimination profile in any extraocular tissue of rabbits was unique to azithromycin, and led to the demonstration of high exposures of azithromycin in all extraocular tissues after ophthalmic administration. FUNDING: This research and Rapid Service Fees were supported by Senju Pharmaceutical Co., Ltd.

16.
J Exp Bot ; 70(20): 5929-5941, 2019 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-31376280

RESUMO

Phototropin1 (phot1) perceives low- to high-fluence blue light stimuli and mediates both the first and second positive phototropisms. High-fluence blue light is known to induce autophosphorylation of phot1, leading to the second positive phototropism. However, the phosphorylation status of phot1 by low-fluence blue light that induces the first positive phototropism had not been observed. Here, we conducted a phosphoproteomic analysis of maize coleoptiles to investigate the fluence-dependent phosphorylation status of Zmphot1. High-fluence blue light induced phosphorylation of Zmphot1 at several sites. Notably, low-fluence blue light significantly increased the phosphorylation level of Ser291 in Zmphot1. Furthermore, Ser291-phosphorylated and Ser369Ser376-diphosphorylated peptides were found to be more abundant in the low-fluence blue light-irradiated sides than in the shaded sides of coleoptiles. The roles of these phosphorylation events in phototropism were explored by heterologous expression of ZmPHOT1 in the Arabidopsis thaliana phot1phot2 mutant. The first positive phototropism was restored in wild-type ZmPHOT1-expressing plants; however, plants expressing S291A-ZmPHOT1 or S369AS376A-ZmPHOT1 showed significantly reduced complementation rates. All transgenic plants tested in this study exhibited a normal second positive phototropism. These findings provide the first indication that low-fluence blue light induces phosphorylation of Zmphot1 and that this induced phosphorylation is crucial for the first positive phototropism.


Assuntos
Proteínas de Arabidopsis/metabolismo , Luz , Fototropismo/fisiologia , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/genética , Fosforilação/genética , Fosforilação/efeitos da radiação , Fototropismo/genética , Fototropismo/efeitos da radiação , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/efeitos da radiação , Zea mays/genética , Zea mays/metabolismo , Zea mays/efeitos da radiação
17.
Plant Physiol ; 180(2): 1119-1131, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30918082

RESUMO

Phototropin (phot) receptor kinases play important roles in promoting plant growth by controlling light-capturing processes, such as phototropism. Phototropism is mediated through the action of NON-PHOTOTROPIC HYPOCOTYL3 (NPH3), which is dephosphorylated following phot activation. However, the functional significance of this early signaling event remains unclear. Here, we show that the onset of phototropism in dark-grown (etiolated) seedlings of Arabidopsis (Arabidopsis thaliana) and tomato (Solanum lycopersicum) is enhanced by greening (deetiolation). Red and blue light were equally effective in promoting phototropism in Arabidopsis, consistent with our observations that deetiolation by phytochrome or cryptochrome was sufficient to enhance phototropism. Increased responsiveness did not result from an enhanced sensitivity to the phytohormone auxin, nor does it involve the phot-interacting protein, ROOT PHOTOTROPISM2. Instead, deetiolated seedlings showed attenuated levels of NPH3 dephosphorylation and diminished relocalization of NPH3 from the plasma membrane during phototropism. Likewise, etiolated seedlings that lack the PHYTOCHROME-INTERACTING FACTORS (PIFs) PIF1, PIF3, PIF4, and PIF5 displayed reduced NPH3 dephosphorylation and enhanced phototropism, consistent with their constitutive photomorphogenic phenotype in darkness. Phototropic enhancement could also be achieved in etiolated seedlings by lowering the light intensity to diminish NPH3 dephosphorylation. Thus, phototropism is enhanced following deetiolation through the modulation of a phosphorylation rheostat, which in turn sustains the activity of NPH3. We propose that this dynamic mode of regulation enables young seedlings to maximize their establishment under changing light conditions, depending on their photoautotrophic capacity.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Estiolamento/fisiologia , Fototropismo/fisiologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/genética , Criptocromos/metabolismo , Estiolamento/efeitos dos fármacos , Estiolamento/efeitos da radiação , Proteínas de Fluorescência Verde/metabolismo , Hipocótilo/efeitos dos fármacos , Hipocótilo/fisiologia , Hipocótilo/efeitos da radiação , Ácidos Indolacéticos/farmacologia , Luz , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Fosforilação/efeitos da radiação , Fototropismo/efeitos dos fármacos , Fototropismo/efeitos da radiação , Fitocromo/metabolismo , Agregados Proteicos , Plântula/efeitos dos fármacos , Plântula/fisiologia , Plântula/efeitos da radiação
18.
Methods Mol Biol ; 1924: 157-163, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30694473

RESUMO

Altered auxin distribution patterns and the formation of a lateral auxin gradient are often discussed in the context of phototropism. The DR5rev::GFP auxin reporter gene is commonly used in phototropism research in Arabidopsis. This study describes a fluorescent auxin analog, NBD-NAA, as an additional tool for the determination of auxin flow during phototropic responses.


Assuntos
Ácidos Indolacéticos/metabolismo , Fototropismo/fisiologia , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas de Arabidopsis/metabolismo
19.
BMJ Open ; 9(12): e030101, 2019 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-31888923

RESUMO

OBJECTIVES: The rate of admissions for ambulatory care sensitive conditions (ACSCs) is a key outcome indicator for primary care, and patient experience (PX) is a crucial process indicator. Studies have reported higher rates of admission for ACSCs in rural areas than in urban areas. Whether there is an association between admissions for ACSCs and PX in rural areas has not been examined. This study aimed to document admissions for ACSCs on Japanese rural islands, and assess whether there was an association between the rate of admissions for ACSCs and PX. DESIGN: Multicentred, prospective, cohort study SETTING: This study was conducted on five rural islands in Okinawa, Japan. PARTICIPANTS: The study participants were all island inhabitants aged 65 years or older. PRIMARY OUTCOME MEASURES: This study examined the association between ACSCs and PX assessed by a questionnaire, the Japanese Version of Primary Care Assessment Tool. ACSCs were classified using the International Classification of Diseases, Tenth Revision, and the rate of admissions for ACSCs in 1 year. RESULTS: Of 1258 residents, 740 completed the questionnaire. This study documented 38 admissions for ACSCs (29 patients, males/females: 15/14, median age 81.9) that included congestive heart failure (11), pneumonia (7) and influenza (5). After adjusting for covariates and geographical clustering, admissions for ACSCs had a significant positive association with each patient's PX scores (OR per 1 SD increase=1.62, 95% CI 1.02-2.61). CONCLUSIONS: Physicians serving rural areas need to stress the importance of preventive interventions for heart failure, pneumonia and influenza to reduce the number of admissions for ACSCs. Contrary to previous studies, our findings might be explained by close patient-doctor relationships on the rural islands.


Assuntos
Assistência Ambulatorial/normas , Atenção Primária à Saúde/normas , Serviços de Saúde Rural/organização & administração , Idoso , Idoso de 80 Anos ou mais , Assistência Ambulatorial/organização & administração , Assistência Ambulatorial/estatística & dados numéricos , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Ilhas , Japão , Modelos Logísticos , Masculino , Atenção Primária à Saúde/estatística & dados numéricos , Estudos Prospectivos , População Rural
20.
Plant Signal Behav ; 13(11): e1536631, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30373470

RESUMO

Recently, we reported that the D6 protein kinase subfamily, which belongs to the AGCVIII kinase family, is a critical component of hypocotyl phototropism in Arabidopsis seedlings. Furthermore, we demonstrated that AGC1-12, which is also a member of the AGCVIII kinase family, is involved in both the pulse-induced first positive phototropism and gravitropism in Arabidopsis hypocotyls. Those results indicated that phosphorylation control is an important mechanism in phototropic signaling. As phosphorylation regulation is controlled by both kinases and phosphatases, we investigated the roles of phosphatases in hypocotyl phototropism. Our physiological analysis, which was performed using Arabidopsis mutants, indicated that the flower-specific, phytochrome-associated protein phosphatase family, which functions as a catalytic subunit of protein phosphatase 6 (PP6), is involved in both the pulse-induced first positive phototropism and the time-dependent second positive phototropism, although it is not necessary for the continuous-light-induced second positive phototropism. These results suggest that not only kinases, but also phosphatases play critical roles in hypocotyl phototropism to control phosphorylation status and that PP6-type protein phosphatases may act antagonistically with AGCVIII protein kinases on the same targets, such as PIN-formed proteins.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Arabidopsis/fisiologia , Hipocótilo/enzimologia , Hipocótilo/fisiologia , Fosfoproteínas Fosfatases/metabolismo , Fototropismo/fisiologia , Plântula/enzimologia , Plântula/fisiologia , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Fosfoproteínas Fosfatases/genética , Fototropismo/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA