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1.
JAMA Psychiatry ; 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38381417

RESUMO

Importance: Current interventions for posttraumatic stress disorder (PTSD) are efficacious, yet effectiveness may be limited by adverse effects and high withdrawal rates. Acupuncture is an emerging intervention with positive preliminary data for PTSD. Objective: To compare verum acupuncture with sham acupuncture (minimal needling) on clinical and physiological outcomes. Design, Setting, and Participants: This was a 2-arm, parallel-group, prospective blinded randomized clinical trial hypothesizing superiority of verum to sham acupuncture. The study was conducted at a single outpatient-based site, the Tibor Rubin VA Medical Center in Long Beach, California, with recruitment from April 2018 to May 2022, followed by a 15-week treatment period. Following exclusion for characteristics that are known PTSD treatment confounds, might affect biological assessment, indicate past nonadherence or treatment resistance, or indicate risk of harm, 93 treatment-seeking combat veterans with PTSD aged 18 to 55 years were allocated to group by adaptive randomization and 71 participants completed the intervention protocols. Interventions: Verum and sham were provided as 1-hour sessions, twice weekly, and participants were given 15 weeks to complete up to 24 sessions. Main Outcomes and Measures: The primary outcome was pretreatment to posttreatment change in PTSD symptom severity on the Clinician-Administered PTSD Scale-5 (CAPS-5). The secondary outcome was pretreatment to posttreatment change in fear-conditioned extinction, assessed by fear-potentiated startle response. Outcomes were assessed at pretreatment, midtreatment, and posttreatment. General linear models comparing within- and between-group were analyzed in both intention-to-treat (ITT) and treatment-completed models. Results: A total of 85 male and 8 female veterans (mean [SD] age, 39.2 [8.5] years) were randomized. There was a large treatment effect of verum (Cohen d, 1.17), a moderate effect of sham (d, 0.67), and a moderate between-group effect favoring verum (mean [SD] Δ, 7.1 [11.8]; t90 = 2.87, d, 0.63; P = .005) in the intention-to-treat analysis. The effect pattern was similar in the treatment-completed analysis: verum d, 1.53; sham d, 0.86; between-group mean (SD) Δ, 7.4 (11.7); t69 = 2.64; d, 0.63; P = .01). There was a significant pretreatment to posttreatment reduction of fear-potentiated startle during extinction (ie, better fear extinction) in the verum but not the sham group and a significant correlation (r = 0.31) between symptom reduction and fear extinction. Withdrawal rates were low. Conclusions and Relevance: The acupuncture intervention used in this study was clinically efficacious and favorably affected the psychobiology of PTSD in combat veterans. These data build on extant literature and suggest that clinical implementation of acupuncture for PTSD, along with further research about comparative efficacy, durability, and mechanisms of effects, is warranted. Trial Registration: ClinicalTrials.gov Identifier: NCT02869646.

2.
Int J Mol Sci ; 25(2)2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38256256

RESUMO

Global climate change has caused severe abiotic and biotic stresses, affecting plant growth and food security. The mechanical understanding of plant stress responses is critical for achieving sustainable agriculture. Intrinsically disordered proteins (IDPs) are a group of proteins without unique three-dimensional structures. The environmental sensitivity and structural flexibility of IDPs contribute to the growth and developmental plasticity for sessile plants to deal with environmental challenges. This article discusses the roles of various disordered proteins in plant stress tolerance and resistance, describes the current mechanistic insights into unstructured proteins such as the disorder-to-order transition for adopting secondary structures to interact with specific partners (i.e., cellular membranes, membrane proteins, metal ions, and DNA), and elucidates the roles of liquid-liquid phase separation driven by protein disorder in stress responses. By comparing IDP studies in animal systems, this article provides conceptual principles of plant protein disorder in stress adaptation, reveals the current research gaps, and advises on the future research direction. The highlighting of relevant unanswered questions in plant protein disorder research aims to encourage more studies on these emerging topics to understand the mechanisms of action behind their stress resistance phenotypes.


Assuntos
Proteínas Intrinsicamente Desordenadas , Animais , Proteínas de Plantas , Proteínas de Membrana , Agricultura , Desenvolvimento Embrionário
3.
Biomolecules ; 13(4)2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-37189374

RESUMO

Microtubules (MTs) are essential elements of the eukaryotic cytoskeleton and are critical for various cell functions. During cell division, plant MTs form highly ordered structures, and cortical MTs guide the cell wall cellulose patterns and thus control cell size and shape. Both are important for morphological development and for adjusting plant growth and plasticity under environmental challenges for stress adaptation. Various MT regulators control the dynamics and organization of MTs in diverse cellular processes and response to developmental and environmental cues. This article summarizes the recent progress in plant MT studies from morphological development to stress responses, discusses the latest techniques applied, and encourages more research into plant MT regulation.


Assuntos
Citoesqueleto , Microtúbulos , Plantas , Aclimatação , Adaptação Fisiológica
4.
Mol Oncol ; 17(8): 1613-1627, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36931723

RESUMO

Extracellular vesicles (EVs) are an important regulatory factor for natural killer cell activity (NKA) in the tumor microenvironment. The relationship between circulating EVs in the peripheral blood and natural killer (NK) cells in prostate cancer (PCa) is unclear. This study aimed at investigating the key regulators in the interaction between circulating EVs and NK cells in PCa patients before and after tumor removal. NK-cell characteristics were prospectively assessed in 79 patients treated with robot-assisted laparoscopic radical prostatectomy preoperatively and postoperatively. Compared with healthy donors, the existence of prostate tumors increased the number of circulating EVs and altered ligand expression of EVs. Circulating EVs extracted from cancer patients significantly decreased NKA of NK cells compared with those extracted from healthy donors. Upon treatment with an inhibiting antibody or small interfering RNA, natural killer cell protein group 2A (NKG2A) was identified as the main NKA regulator in cancer patients for accepting the signal from circulating EVs. After surgery, NKA was increased and NKG2A expression on NK cells was significantly reduced. The expression of ligands for natural killer cell protein group 2D (NKG2D) on EVs and the level of circulation EVs both significantly increased. With the decrease in NKG2A levels on NK cells and the increase in total NKG2D ligands on circulating EVs, which was increased postoperatively, both NKG2A on NK cells and NKG2D ligands on circulating exosomes are main regulators of NKA restoration after prostatectomy.


Assuntos
Vesículas Extracelulares , Neoplasias da Próstata , Masculino , Humanos , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Ligantes , Células Matadoras Naturais/metabolismo , Vesículas Extracelulares/metabolismo , Neoplasias da Próstata/patologia , Prostatectomia , Microambiente Tumoral
5.
Front Plant Sci ; 13: 976627, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36204075
6.
Med Acupunct ; 34(3): 172-176, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35832108

RESUMO

Background: The long-COVID syndrome (LCS), defined by residual symptoms from acute COVID-19 for <60 days, affects about one-third of all COVID survivors and is an emerging public health challenge. Empirical data about the range of symptoms or the utility of acupuncture alone for the LCS are very limited. Case: This observational case study of a 46-year-old male with LCS was conducted to preliminarily define the range of symptoms, a Traditional Chinese Medicine (TCM) diagnostic structure, and evaluate the potential utility of prescribed acupuncture for LCS. Results: The primary TCM diagnostic patterns from this patient's LCS presentation included Lung Qi and Yin Deficiency, Qi and Blood Stagnation, and Spleen Qi Deficiency with dampness. Acupuncture for this patient was associated with reduced symptoms and signs of LCS. Conclusion: A preliminary TCM diagnostic structure for LCS was defined. Acupuncture appears to have been helpful for a patient with LCS. Further research is needed to demonstrate the efficacy of acupuncture and/or other TCM modalities for LCS.

7.
Med Acupunct ; 34(3): 167-171, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35832113

RESUMO

Introduction: The postacute sequelae of COVID-19 (PASC) is a serious heterogeneous condition that affects a significant minority of those who endured COVID-19. PASC involves multiple body systems and an illness trajectory that has stages now being identified in medical research. Objective: Traditional Chinese Medicine (TCM) and acupuncture are well suited to conceptualize and treat PASC and other postviral conditions. No description of TCM theory and its relationship with modern medical theory about PASC and its illness trajectory currently exists. Conclusion: The authors provide an overview of the potential value of TCM for conceptualizing and treating PASC with a few examples and clarify directions for research.

8.
Chaos ; 32(5): 053101, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35649982

RESUMO

It is well-known that the interruption of transmission of a disease can be achieved, provided the vaccinated population reaches a threshold depending on, among others, the efficacy of vaccines. The purpose of this paper is to address the optimal vaccination strategy by imposing the economic constraints. In particular, an S--(I,V)--S model used to describe the spreading of the disease in a well-mixed population and a cost function consisting of vaccination and infection costs are proposed. The well-definedness of the above-described modeling is provided. We were then able to provide an optimal strategy to minimize the cost for all parameters. In particular, the optimal vaccination level to minimize the cost can be completely characterized for all parameters. For instance, the optimal vaccination level can be classified by the magnitude of the failure rate of the vaccine with other parameters being given. Under these circumstances, the optimal strategy to minimize the cost is roughly to eliminate the disease locally (respectively, choose an economic optimum resulting in not to wipe out the disease completely or take no vaccination for anyone) provided the vaccine failure rate is relatively small (respectively, intermediate or large). Numerical simulations to illustrate our main results are also provided. Moreover, the data collected at the height of the Covid-19 pandemic in Taiwan are also numerically simulated to provide the corresponding optimal vaccination strategy.


Assuntos
COVID-19 , Pandemias , COVID-19/epidemiologia , COVID-19/prevenção & controle , Humanos , Pandemias/prevenção & controle , Vacinação
10.
Trials ; 22(1): 594, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34488824

RESUMO

BACKGROUND: Post-traumatic stress disorder (PTSD) is a significant public health problem, affecting approximately 7% of the general population and 13-18% of the combat Veteran population. The first study using acupuncture for PTSD in a civilian population showed large pre- to post-treatment effects for an empirically developed verum protocol, which was equivalent to group cognitive behavior therapy and superior to a wait-list control. The primary objective of this study is to determine both clinical and biological effects of verum acupuncture for combat-related PTSD in treatment-seeking US Veterans. METHODS: This is a two-arm, parallel-group, prospective randomized placebo-controlled clinical trial. The experimental condition is verum acupuncture and the placebo control is sham (minimal) acupuncture in 1-h sessions, twice a week for 12 weeks. Ninety subjects will provide adequate power and will be allocated to group by an adaptive randomization procedure. The primary outcome is change in PTSD symptom severity from pre- to post-treatment. The secondary biological outcome is change from pre- to post-treatment in psychophysiological response, startle by electromyographic (EMG) eyeblink. Assessments will be conducted at pre-, mid-, post-, and 1-month post-treatment, blind to group allocation. Intent-to-treat analyses will be conducted. DISCUSSION: The study results will be definitive because both clinical and biological outcomes will be assessed and correlated. Issues such as the number needed for recruitment and improvement, use of sham acupuncture, choice of biological measure, and future research need will be discussed. TRIAL REGISTRATION: ClinicalTrials.gov NCT02869646 . Registered on 17 August 2016.


Assuntos
Terapia por Acupuntura , Transtornos de Estresse Pós-Traumáticos , Veteranos , Terapia por Acupuntura/efeitos adversos , Humanos , Estudos Prospectivos , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/terapia , Resultado do Tratamento
11.
Complement Ther Med ; 63: 102775, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34537344

RESUMO

OBJECTIVES: The aim of this study was to critically appraise and evaluate effects of low- and high-dose curcuminoids on pain and functional improvement in patients with knee osteoarthritis (OA) and to compare adverse events (AEs) between curcuminoids and non-steroid anti-inflammatory drugs (NSAIDs). METHODS: We systematically reviewed all randomized controlled trials (RCTs) on curcuminoids in knee osteoarthritis from the PubMed, Embase, Cochrane Library, AMED, Cinahl, ISI Web of Science, Chinese medical database, and Indian Scientific databases from inception to June 21, 2021. RESULTS: We included eleven studies with a total of 1258 participants with primary knee OA. The meta-analysis results showed that curcuminoids were significantly more effective than comparators regarding visual analogue scale (VAS) and Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain scores. However, no significant difference in pain relief or AEs between the high-dose (daily dose ≥1000 mg or total dose ≥42 gm) and low-dose (daily dose <1000 mg or total dose <42 gm) curcuminoid treatments was observed. When comparing curcumininoids versus NSAIDs, a significant difference in VAS pain was found. For AE analysis, three of our included studies used NSAIDs as comparators, with all reporting higher AE rates in the NSAID group, though significance was reached in only one study. CONCLUSIONS: The results of our meta-analysis suggest that low- and high-dose curcuminoids have similar pain relief effects and AEs in knee OA. Curcuminoids are also associated with better pain relief than NSAIDs; therefore, using curcuminoids as an adjunctive treatment in knee OA is recommended.


Assuntos
Curcumina , Osteoartrite do Joelho , Anti-Inflamatórios não Esteroides/uso terapêutico , Curcumina/uso terapêutico , Humanos , Articulação do Joelho , Osteoartrite do Joelho/tratamento farmacológico , Medição da Dor , Resultado do Tratamento
12.
Med Eng Phys ; 81: 1-12, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32475768

RESUMO

During bone burring, the heat generated due to friction at the bone-burr interface may cause thermal damage to the bone. Therefore, it is necessary to assess bone temperature distribution around a burring site and identify high-risk regions for thermal necrosis due to bone burring. In this study, a three-dimensional (3-D) dynamic elastoplastic finite element model for the burring process was developed and experimentally validated to investigate the influence of burring parameters (rotational speeds: 3,000, 10,000, 15,000 and 60,000 rpm; feed rates: 0.5, 0.9, 1.5 and 3.0 mm/s) on heat generation and evaluate the risk region for thermal necrosis. Calculated bone temperatures were compared with experimental values and found to be in good agreement with them. The analytical results demonstrated a linear relationship between the burring time and friction energy. In addition, the friction energy increased with the bone temperature. The high-risk thermal necrosis zone was measured from the edge of burring (y-direction) at feed rates of 0.5, 0.9, 1.5 and 3.0 mm/s and was found to be 7.8, 7.3, 6.6 and 5.5 mm, respectively. When the burr rotational speed increased from 3,000 to 60,000 rpm, the high-risk zone for thermal necrosis increased from 4.5 to 8.1 mm. We concluded that both the friction energy and the bone temperature increased in proportion with the burr rotational speed. Reducing burr rotational speeds and/or increasing feed rates may decrease the rise in bone temperature, thus decreasing the potential for thermal necrosis near the burring site. Our model can be used to select the optimal surgery parameters to minimise the risk of thermal necrosis due to bone burring and to assist in the design of optimal orthopaedic drill handpieces.


Assuntos
Osso e Ossos/patologia , Osso e Ossos/cirurgia , Análise de Elementos Finitos , Temperatura Alta , Procedimentos Ortopédicos/efeitos adversos , Humanos , Necrose , Medição de Risco , Rotação , Fatores de Tempo
13.
Plant Physiol ; 183(2): 570-587, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32238442

RESUMO

Intrinsically disordered proteins function as flexible stress modulators in vivo through largely unknown mechanisms. Here, we elucidated the mechanistic role of an intrinsically disordered protein, REPETITIVE PRO-RICH PROTEIN (RePRP), in regulating rice (Oryza sativa) root growth under water deficit. With nearly 40% Pro, RePRP is induced by water deficit and abscisic acid (ABA) in the root elongation zone. RePRP is sufficient and necessary for repression of root development by water deficit or ABA. We showed that RePRP interacts with the highly ordered cytoskeleton components actin and tubulin both in vivo and in vitro. Binding of RePRP reduces the abundance of actin filaments, thus diminishing noncellulosic polysaccharide transport to the cell wall and increasing the enzyme activity of Suc synthase. RePRP also reorients the microtubule network, which leads to disordered cellulose microfibril organization in the cell wall. The cell wall modification suppresses root cell elongation, thereby generating short roots, whereas increased Suc synthase activity triggers starch accumulation in "heavy" roots. Intrinsically disordered proteins control cell elongation and carbon reserves via an order-by-disorder mechanism, regulating the highly ordered cytoskeleton for development of "short-but-heavy" roots as an adaptive response to water deficit in rice.


Assuntos
Citoesqueleto/metabolismo , Proteínas Intrinsicamente Desordenadas/metabolismo , Microtúbulos/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Ácido Abscísico/metabolismo , Citoesqueleto/genética , Regulação da Expressão Gênica de Plantas , Proteínas Intrinsicamente Desordenadas/genética , Oryza/genética , Proteínas de Plantas/genética , Raízes de Plantas/genética
14.
Plant Biotechnol J ; 18(9): 1969-1983, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32034845

RESUMO

Grain/seed yield and plant stress tolerance are two major traits that determine the yield potential of many crops. In cereals, grain size is one of the key factors affecting grain yield. Here, we identify and characterize a newly discovered gene Rice Big Grain 1 (RBG1) that regulates grain and organ development, as well as abiotic stress tolerance. Ectopic expression of RBG1 leads to significant increases in the size of not only grains but also other major organs such as roots, shoots and panicles. Increased grain size is primarily due to elevated cell numbers rather than cell enlargement. RBG1 is preferentially expressed in meristematic and proliferating tissues. Ectopic expression of RBG1 promotes cell division, and RBG1 co-localizes with microtubules known to be involved in cell division, which may account for the increase in organ size. Ectopic expression of RBG1 also increases auxin accumulation and sensitivity, which facilitates root development, particularly crown roots. Moreover, overexpression of RBG1 up-regulated a large number of heat-shock proteins, leading to enhanced tolerance to heat, osmotic and salt stresses, as well as rapid recovery from water-deficit stress. Ectopic expression of RBG1 regulated by a specific constitutive promoter, GOS2, enhanced harvest index and grain yield in rice. Taken together, we have discovered that RBG1 regulates two distinct and important traits in rice, namely grain yield and stress tolerance, via its effects on cell division, auxin and stress protein induction.


Assuntos
Oryza , Divisão Celular , Grão Comestível/metabolismo , Regulação da Expressão Gênica de Plantas , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
15.
FASEB J ; 33(5): 6281-6295, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30789794

RESUMO

Several pregnancy complications result from abnormal trophoblast invasion. The dichotomous effect of TGF-ß on epithelial-mesenchymal transition (EMT) between trophoblast invasion and cancer progression remains unknown and a critical concern. We attenuated the expression of TGF-ß type 1 receptor (coding by TGFBR1) with RNA interference in trophoblastic cells and significantly enhanced the trophoblastic invasion. Analysis of microRNA profiles in trophoblasts indicated microRNA-7 as a key molecule linking TGF-ß with the negative regulation of trophoblast invasion. We then attenuated TGFBR1 and miR-7 transcription by transducing either short hairpin RNA targeting TGFBR1 or anti-miR-7-locked nucleonic acid, and we observed an up-regulation of EMT-related transcription factors (TFs) and their downstream effectors, causing a mesenchymal transition of trophoblasts. Conversely, overexpression of TGFBR1 or miR-7 led to the epithelial transition of trophoblasts. Our results showed that TGF-ß-induced miR-7 expression negatively modulated the TGF-ß-SMAD family member 2-mediated EMT pathway via targeting EMT-related TFs and down-regulating their mesenchymal markers. These findings possibly explain, at least in part, why TGF-ß exerts an opposite effect on EMT during trophoblast invasion and cancer progression.-Shih, J.-C., Lin, H.-H., Hsiao, A.-C., Su, Y.-T., Tsai, S., Chien, C.-L., Kung, H.-N. Unveiling the role of microRNA-7 in linking TGF-ß-Smad-mediated epithelial-mesenchymal transition with negative regulation of trophoblast invasion.


Assuntos
Carcinogênese/metabolismo , Transição Epitelial-Mesenquimal , MicroRNAs/metabolismo , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Trofoblastos/metabolismo , Carcinogênese/patologia , Movimento Celular , Células HEK293 , Humanos , MicroRNAs/genética , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Trofoblastos/patologia , Trofoblastos/fisiologia
16.
FEBS Open Bio ; 8(8): 1230-1246, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30087829

RESUMO

A high-efficiency laccase, DLac, was isolated from Cerrena sp. RSD1. The kinetic studies indicate that DLac is a diffusion-limited enzyme. The crystal structure of DLac was determined to atomic resolution, and its overall structure shares high homology to monomeric laccases, but displays unique substrate-binding loops from those in other laccases. The substrate-binding residues with small side chain and the short substrate-binding loop IV broaden the substrate-binding cavity and may facilitate large substrate diffusion. Unlike highly glycosylated fungal laccases, the less-glycosylated DLac contains one highly conserved glycosylation site at N432 and an unique glycosylation site at N468. The N-glycans stabilize the substrate-binding loops and the protein structure, and the first N-acetylglucosamine is crucial for the catalytic efficiency. Additionally, a fivefold increase in protein yield is achieved via the submerged culture method for industrial applications. DATABASE: The atomic coordinates of the structure of DLac from Cerrena sp. RSD1 and structural factors have been deposited in the RCSB Protein Data Bank (PDB ID: 5Z1X).

17.
New Phytol ; 218(1): 183-200, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29288621

RESUMO

Fatty acids (FAs) and sterols constitute building blocks of eukaryotic membranes and lipid signals. Co-regulation of FA and sterol synthesis is mediated by sterol regulatory element-binding proteins in animals but remains elusive in plants. We reported recently that Arabidopsis ACYL-COA-BINDING PROTEIN1 (ACBP1) modulates sterol synthesis via protein-protein interaction with STEROL C4-METHYL OXIDASE1-1 (SMO1-1). Herein, ACBP1 was demonstrated to co-express and interact with SMO1-2 by yeast two-hybrid, co-localization, pull-down, co-immunoprecipitation and ß-glucuronidase assays. SMO1-2 silenced in acbp1 was used in phenotyping, GC-MS and expression profiling. ACBP1 co-expressed with SMO1-2 in embryo sacs, pollen and trichomes, corroborating with cooperative tissue-specific functions unseen with SMO1-1. SMO1-2 silencing in acbp1 impaired seed development, male and female gamete transmission, and pollen function. Genes encoding homeodomain-leucine zipper IV transcription factors (HDG5, HDG10, HDG11 and GLABRA2), which potentially bind phospholipids/sterols, were transcribed aberrantly. GLABRA2 targets (MYB23, MUM4 and PLDα1) were misregulated, causing glabra2-resembling trichome, seed coat mucilage and oil-accumulating phenotypes. Together with altered sterol and FA compositions upon ACBP1 mutation and/or SMO1-2 silencing, ACBP1-SMO1 interaction appears to mediate homeostatic co-regulation of FAs and sterols, which serve as lipid modulators for gene expression of homeodomain-leucine zipper IV transcription factors.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Fatores de Transcrição de Zíper de Leucina Básica/genética , Proteínas de Transporte/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Homeodomínio/genética , Oxigenases de Função Mista/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Retículo Endoplasmático/metabolismo , Ácidos Graxos/metabolismo , Flores/metabolismo , Inativação Gênica , Células Germinativas Vegetais/metabolismo , Germinação , Proteínas de Homeodomínio/metabolismo , Complexos Multiproteicos/metabolismo , Mutação/genética , Fenótipo , Raízes de Plantas/metabolismo , Tubo Polínico/crescimento & desenvolvimento , Ligação Proteica , Reprodução , Sementes/embriologia , Sementes/genética , Esteróis/metabolismo , Tricomas/metabolismo
18.
Plant Cell Physiol ; 58(9): 1494-1506, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28922746

RESUMO

Ectopic expression of the rice WINDING 1 (WIN1) gene leads to a spiral phenotype only in shoots but not in roots. Rice WIN1 belongs to a specific class of proteins in cereal plants containing a Bric-a-Brac/Tramtrack/Broad (BTB) complex, a non-phototropic hypocotyl 3 (NPH3) domain and a coiled-coil motif. The WIN1 protein is predominantly localized to the plasma membrane, but is also co-localized to plasmodesmata, where it exhibits a punctate pattern. It is observed that WIN1 is normally expressed in roots and the shoot-root junction, but not in the rest of shoots. In roots, WIN1 is largely localized to the apical and basal sides of cells. However, upon ectopic expression, WIN1 appears on the longitudinal sides of leaf sheath cells, correlated with the appearance of a spiral phenotype in shoots. Despite the spiral phenotype, WIN1-overexpressing plants exhibit a normal phototropic response. Although treatments with exogenous auxins or a polar auxin transport inhibitor do not alter the spiral phenotype, the excurvature side has a higher auxin concentration than the incurvature side. Furthermore, actin filaments are more prominent in the excurvature side than in the incurvature side, which correlates with cell size differences between these two sides. Interestingly, ectopic expression of WIN1 does not cause either unequal auxin distribution or actin filament differences in roots, so a spiral phenotype is not observed in roots. The action of WIN1 appears to be different from that of other proteins causing a spiral phenotype, and it is likely that WIN1 is involved in 1-N-naphthylphthalamic acid-insensitive plasmodesmata-mediated auxin transport.


Assuntos
Ácidos Indolacéticos/metabolismo , Oryza/anatomia & histologia , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Actinas/metabolismo , Proliferação de Células/efeitos dos fármacos , Escuridão , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ácidos Indolacéticos/farmacologia , Família Multigênica , Oryza/genética , Oryza/crescimento & desenvolvimento , Fenótipo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas , Plasmodesmos/efeitos dos fármacos , Plasmodesmos/metabolismo , Transporte Proteico/efeitos dos fármacos
19.
Plant Physiol ; 174(3): 1420-1435, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28500265

RESUMO

Fatty acids (FAs) and sterols are primary metabolites that exert interrelated functions as structural and signaling lipids. Despite their common syntheses from acetyl-coenzyme A, homeostatic cross talk remains enigmatic. Six Arabidopsis (Arabidopsis thaliana) acyl-coenzyme A-binding proteins (ACBPs) are involved in FA metabolism. ACBP1 interacts with PHOSPHOLIPASE Dα1 and regulates phospholipid composition. Here, its specific role in the negative modulation of sterol synthesis during embryogenesis is reported. ACBP1, likely in a liganded state, interacts with STEROL C4-METHYL OXIDASE1-1 (SMO1-1), a rate-limiting enzyme in the sterol pathway. Proembryo abortion in the double mutant indicated that the ACBP1-SMO1-1 interaction is synthetic lethal, corroborating with their strong promoter activities in developing ovules. Gas chromatography-mass spectrometry revealed quantitative and compositional changes in FAs and sterols upon overexpression or mutation of ACBP1 and/or SMO1-1 Aberrant levels of these metabolites may account for the downstream defect in lipid signaling. GLABRA2 (GL2), encoding a phospholipid/sterol-binding homeodomain transcription factor, was up-regulated in developing seeds of acbp1, smo1-1, and ACBP1+/-smo1-1 in comparison with the wild type. Consistent with the corresponding transcriptional alteration of GL2 targets, high-oil, low-mucilage phenotypes of gl2 were phenocopied in ACBP1+/-smo1-1 Thus, ACBP1 appears to modulate the metabolism of two important lipid classes (FAs and sterols) influencing cellular signaling.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/embriologia , Arabidopsis/metabolismo , Proteínas de Transporte/metabolismo , Sementes/metabolismo , Esteróis/biossíntese , Arabidopsis/genética , Retículo Endoplasmático/metabolismo , Ácidos Graxos/metabolismo , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Técnicas de Silenciamento de Genes , Proteínas de Homeodomínio/metabolismo , Mutação/genética , Fenótipo , Plantas Geneticamente Modificadas , Polinização , Mapeamento de Interação de Proteínas , Reprodução
20.
Nutr Res ; 35(11): 982-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26409342

RESUMO

Bioelectrical impedance analysis (BIA) is commonly used to assess body composition. Cross-mode (left hand to right foot, Z(CR)) BIA presumably uses the longest current path in the human body, which may generate better results when estimating fat-free mass (FFM). We compared the cross-mode with the hand-to-foot mode (right hand to right foot, Z(HF)) using dual-energy x-ray absorptiometry (DXA) as the reference. We hypothesized that when comparing anthropometric parameters using stepwise regression analysis, the impedance value from the cross-mode analysis would have better prediction accuracy than that from the hand-to-foot mode analysis. We studied 264 men and 232 women (mean ages, 32.19 ± 14.95 and 34.51 ± 14.96 years, respectively; mean body mass indexes, 24.54 ± 3.74 and 23.44 ± 4.61 kg/m2, respectively). The DXA-measured FFMs in men and women were 58.85 ± 8.15 and 40.48 ± 5.64 kg, respectively. Multiple stepwise linear regression analyses were performed to construct sex-specific FFM equations. The correlations of FFM measured by DXA vs. FFM from hand-to-foot mode and estimated FFM by cross-mode were 0.85 and 0.86 in women, with standard errors of estimate of 2.96 and 2.92 kg, respectively. In men, they were 0.91 and 0.91, with standard errors of the estimates of 3.34 and 3.48 kg, respectively. Bland-Altman plots showed limits of agreement of -6.78 to 6.78 kg for FFM from hand-to-foot mode and -7.06 to 7.06 kg for estimated FFM by cross-mode for men, and -5.91 to 5.91 and -5.84 to 5.84 kg, respectively, for women. Paired t tests showed no significant differences between the 2 modes (P > .05). Hence, cross-mode BIA appears to represent a reasonable and practical application for assessing FFM in Chinese populations.


Assuntos
Absorciometria de Fóton/estatística & dados numéricos , Composição Corporal , Índice de Massa Corporal , Postura , Adolescente , Adulto , Idoso , Impedância Elétrica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto Jovem
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