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1.
Plant Physiol ; 195(2): 970-985, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38478469

RESUMO

The Xishuangbanna (XIS) cucumber (Cucumis sativus var. xishuangbannanesis) is a semiwild variety that has many distinct agronomic traits. Here, long reads generated by Nanopore sequencing technology helped assembling a high-quality genome (contig N50 = 8.7 Mb) of landrace XIS49. A total of 10,036 structural/sequence variations (SVs) were identified when comparing with Chinese Long (CL), and known SVs controlling spines, tubercles, and carpel number were confirmed in XIS49 genome. Two QTLs of hypocotyl elongation under low light, SH3.1 and SH6.1, were fine-mapped using introgression lines (donor parent, XIS49; recurrent parent, CL). SH3.1 encodes a red-light receptor Phytochrome B (PhyB, CsaV3_3G015190). A ∼4 kb region with large deletion and highly divergent regions (HDRs) were identified in the promoter of the PhyB gene in XIS49. Loss of function of this PhyB caused a super-long hypocotyl phenotype. SH6.1 encodes a CCCH-type zinc finger protein FRIGIDA-ESSENTIAL LIKE (FEL, CsaV3_6G050300). FEL negatively regulated hypocotyl elongation but it was transcriptionally suppressed by long terminal repeats retrotransposon insertion in CL cucumber. Mechanistically, FEL physically binds to the promoter of CONSTITUTIVE PHOTOMORPHOGENIC 1a (COP1a), regulating the expression of COP1a and the downstream hypocotyl elongation. These above results demonstrate the genetic mechanism of cucumber hypocotyl elongation under low light.


Assuntos
Cucumis sativus , Genoma de Planta , Hipocótilo , Locos de Características Quantitativas , Hipocótilo/crescimento & desenvolvimento , Hipocótilo/genética , Cucumis sativus/genética , Cucumis sativus/crescimento & desenvolvimento , Locos de Características Quantitativas/genética , Fitocromo B/genética , Fitocromo B/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Luz
2.
BMC Geriatr ; 24(1): 258, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493082

RESUMO

BACKGROUND: Physical activity (PA) plays an important role in the process of several chronic diseases. It may be also associated with the incidence of sarcopenia. This study aimed to determine the association of PA from different components including frequency, duration, intensity, and volume with the incidence of sarcopenia in middle-aged and older adults. METHODS: This study used data from the China Health and Retirement Longitudinal Study in 2011 and 2015. A total of 3,760 individuals aged ≥ 40 years were involved in this study. Sarcopenia was diagnosed using muscle mass, strength and physical performance according to the Asian Working Group for Sarcopenia. PA information including frequency, duration, intensity, and volume was obtained by a self-reported questionnaire. Logistic regression analysis was employed to examine the association between PA and the incidence of sarcopenia at 4-year follow-up. RESULTS: The incidence of sarcopenia was 5.9% during the 4-year follow-up. Compared to sedentary individuals, those taking 1-2 days or more per week, or a minimum of 10 min each time on vigorous-intensity PA (VPA) had a lower incidence of sarcopenia. Adults spending 3 days or more each week, a minimum of 30 min each time, or 150 min or more per week on moderate-intensity PA (MPA) had a lower presence of sarcopenia than sedentary adults. Adults taking 3 days or more per week, at least 30 min each time, or 150 min or more each week on light-intensity PA (LPA) tended to have a lower incidence of sarcopenia than sedentary individuals. Sensitivity analyses confirmed the robustness of the findings after removing persons with hypertension, dyslipidemia, or diabetes. CONCLUSIONS: These findings suggest that the frequency, duration, and volume of VPA or MPA are negatively associated with the presence of sarcopenia. Participation in LPA tends to have a lower incidence of sarcopenia in middle-aged and older adults.


Assuntos
Sarcopenia , Humanos , Pessoa de Meia-Idade , Idoso , Sarcopenia/diagnóstico , Sarcopenia/epidemiologia , Estudos Longitudinais , Incidência , Exercício Físico/fisiologia , China/epidemiologia
3.
Int J Mol Sci ; 25(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38892093

RESUMO

One key post-transcriptional modification mechanism that dynamically controls a number of physiological processes in plants is alternative splicing (AS). However, the functional impacts of AS on fruit ripening remain unclear. In this research, we used RNA-seq data from climacteric (VED, Harukei 3) and non-climacteric (PI, PS) melon cultivars to explore alternative splicing (AS) in immature and mature fruit. The results revealed dramatic changes in differential AS genes (DAG) between the young and mature fruit stages, particularly in genes involved in fruit development/ripening, carotenoid and capsaicinoid biosynthesis, and starch and sucrose metabolism. Serine/arginine-rich (SR) family proteins are known as important splicing factors in AS events. From the melon genome, a total of 17 SR members were discovered in this study. These genes could be classified into eight distinct subfamilies based on gene structure and conserved motifs. Promoter analysis detected various cis-acting regulatory elements involved in hormone pathways and fruit development. Interestingly, these SR genes exhibited specific expression patterns in reproductive organs such as flowers and ovaries. Additionally, concurrent with the increase in AS levels in ripening fruit, the transcripts of these SR genes were activated during fruit maturation in both climacteric and non-climacteric melon varieties. We also found that most SR genes were under selection during domestication. These results represent a novel finding of increased AS levels and SR gene expression during fruit ripening, indicating that alternative splicing may play a role in fruit maturation.


Assuntos
Processamento Alternativo , Cucumis melo , Frutas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Cucumis melo/genética , Cucumis melo/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Perfilação da Expressão Gênica
4.
Cochrane Database Syst Rev ; 5: CD014676, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37249304

RESUMO

BACKGROUND: Acute ischemic stroke (AIS) is the abrupt reduction of blood flow to a certain area of the brain which causes neurologic dysfunction. Different types of percutaneous arterial endovascular interventions have been developed, but as yet there is no consensus on the optimal therapy for people with AIS. OBJECTIVES: To compare the safety and efficacy of different types of percutaneous arterial endovascular interventions for treating people with AIS. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL; Issue 4 of 12, 2022), MEDLINE Ovid (1946 to 13 May 2022), Embase (1947 to 15 May 2022), Science Citation Index Web of Science (1900 to 15 May 2022), Scopus (1960 to 15 May 2022), and China Biological Medicine Database (CBM; 1978 to 16 May 2022). We also searched the ClinicalTrials.gov trials register and the World Health Organization (WHO) International Clinical Trials Registry Platform to 16 May 2022. SELECTION CRITERIA: Randomized controlled trials (RCTs) comparing one percutaneous arterial endovascular intervention with another in treating adult patients who have a clinical diagnosis of AIS due to large vessel occlusion and confirmed by imaging evidence, including thrombo-aspiration, stent-retrieval thrombectomy, aspiration-retriever combined technique, and thrombus mechanical fragmentation. DATA COLLECTION AND ANALYSIS: Two review authors independently performed the literature searches, identified eligible trials, and extracted data. A third review author participated in discussions to reach consensus decisions when any disputes occurred. We assessed risk of bias and applied the GRADE approach to evaluate the quality of the evidence. The primary outcome was rate of modified Rankin Scale (mRS) of 0 to 2 at three months. Secondary outcomes included the rate of modified Thrombolysis In Cerebral Infarction (mTICI) of 2b to 3 postprocedure, all-cause mortality within three months, rate of intracranial hemorrhage on imaging at 24 hours, rate of symptomatic intracranial hemorrhage at 24 hours, and rate of procedure-related adverse events within three months. MAIN RESULTS: Four RCTs were eligible. The current meta-analysis included two trials with 651 participants comparing thrombo-aspiration with stent-retrieval thrombectomy. We judged the quality of evidence to be high in both trials according to Cochrane's risk of bias tool RoB 2. There were no significant differences between thrombo-aspiration and stent-retrieval thrombectomy in rate of mRS of 0 to 2 at three months (risk ratio [RR] 0.97, 95% confidence interval [CI] 0.82 to 1.13; P = 0.68; 633 participants; 2 RCTs); rate of mTICI of 2b to 3 postprocedure (RR 1.01, 95% CI 0.95 to 1.07; P = 0.77; 650 participants; 2 RCTs); all-cause mortality within three months (RR 1.01, 95% CI 0.74 to 1.37; P = 0.95; 633 participants; 2 RCTs); rate of intracranial hemorrhage on imaging at 24 hours (RR 1.03, 95% CI 0.86 to 1.24; P = 0.73; 645 participants; 2 RCTs); rate of symptomatic intracranial hemorrhage at 24 hours (RR 0.90, 95% CI 0.49 to 1.68; P = 0.75; 645 participants; 2 RCTs); and rate of procedure-related adverse events within three months (RR 0.98, 95% CI 0.68 to 1.41; P = 0.90; 651 participants; 2 RCTs). Another two included studies reported no differences for the comparisons of combined therapy versus stent-retrieval thrombectomy or thrombo-aspiration. One RCT is ongoing. AUTHORS' CONCLUSIONS: This review did not establish any difference in safety and effectiveness between the thrombo-aspiration approach and stent-retrieval thrombectomy for treating people with AIS. Furthermore, the combined group did not show any obvious advantage over either intervention applied alone.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Adulto , Humanos , AVC Isquêmico/complicações , Hemorragias Intracranianas , Stents/efeitos adversos , Trombectomia/efeitos adversos , Trombectomia/métodos , China , Acidente Vascular Cerebral/cirurgia , Acidente Vascular Cerebral/tratamento farmacológico
5.
Environ Dev Sustain ; : 1-29, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36687739

RESUMO

How heavily polluting enterprises achieve sustainable development has become an urgent issue to be solved. Based on the data of Chinese heavily polluting listed enterprises during the period of 2010-2020, this paper adopts the probit method to examine how heterogeneous environmental regulations affect green merger and acquisition (GMA) decision, and propensity score matching and difference-in-differences method to explore innovation performance of GMA. The findings are as follows: (1) Command-and-control environmental regulation (CMCER) can promote GMA, while there exists a U-shaped relationship between market-based environmental regulation (MBER) and GMA; (2) from a dynamic perspective, it turns out that GMA can promote green innovation (GI) in the first and second post-acquisition year, but this effect disappears in the third year; (3) compared with CMCER, MBER has a more pronounced positive effect on the relationship between GMA and GI; (4) heterogeneous analysis indicates that the above GMA performance is more persistent when the acquirer is state-owned, with high media attention, with high internal control or engages in vertical GMA. The findings further enrich the literature on GMA driver and performance and provide references for optimizing ER policies and promoting corporate sustainable development.

6.
Opt Express ; 30(4): 5498-5511, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35209511

RESUMO

In this paper, we propose a new kind of optomechanical metamaterial based on a planar ELC-type absorbing structure fabricated on the low-loss flexible substrate. The nonlinear coupling mechanism and nonlinear response phenomenon of the proposed optomechanical metamaterial driven by electromagnetic induced force are analyzed theoretically. The mechanical deformation/displacement and the mechanical resonance frequency shift of the metamaterial unit deposed on the flexible substrate are also numerically and experimentally demonstrated to reveal the coupling phenomenon of electromagnetic field and mechanical field. These results will help researchers to further understand the multi-physics interactions of optomechanical metamaterials and will promote the developments of new type of metasurface for high-efficiency dynamic electromagnetic wave controlling and formatting.

7.
Cochrane Database Syst Rev ; 5: CD013692, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35579383

RESUMO

BACKGROUND: Vertebral artery stenosis (narrowing of the vertebral artery) is an important cause of posterior circulation ischaemic stroke. Medical treatment (MT) e.g. controlling risk-factors and drug treatment, surgery, and endovascular treatment (ET) are the prevailing treatment strategies for symptomatic vertebral artery stenosis. ET consist s of percutaneous transluminal angioplasty (balloon catheter through the skin), with or without stenting. However, optimal management of people with symptomatic vertebral artery stenosis has not yet been established. OBJECTIVES: To assess the safety and efficacy of percutaneous transluminal angioplasty, with or without stenting, combined with MT, compared to MT alone, in people with episodes of cerebral ischaemia due to vertebral artery stenosis. SEARCH METHODS: We searched the Cochrane Stroke Group, MEDLINE, Embase, BIOSIS, and two other indexes in Web of Science, China Biological Medicine Database, Chinese Science and Technique Journals Database, China National Knowledge Infrastructure and Wanfang Data, as well as ClinicalTrials.gov trials register and the World Health Organization (WHO) International Clinical Trials Registry Platform to 23 July 2021. SELECTION CRITERIA: We included all randomised controlled trials (RCTs) that compared ET plus MT with MT alone in treating people aged 18 years or over with symptomatic vertebral artery stenosis. We included all types of ET modalities (e.g. angioplasty alone, balloon-mounted stenting, and angioplasty followed by placement of a self-expanding stent). MT included risk factor control, antiplatelet therapy, lipid-lowering therapy, and individualised management for people with hypertension or diabetes. DATA COLLECTION AND ANALYSIS: Two review authors independently screened potentially eligible studies, extracted data, and assessed trial quality and risk of bias.  We applied the GRADE approach to assess the certainty of evidence. The primary outcomes were 30-day post-randomisation death/stroke (short-term outcome) and fatal/non-fatal stroke after 30 days post-randomisation to completion of follow-up (long-term outcome).  MAIN RESULTS: We included three RCTs with 349 participants with symptomatic vertebral artery stenosis with a mean age of 64.4 years. The included RCTs were at low risk of bias overall. However, all included studies had a high risk of performance bias because blinding of the ET was not feasible. There was no significant difference in 30-day post-randomisation deaths/strokes between ET plus MT and MT alone (risk ratio (RR) 2.33, 95% confidence interval (CI) 0.77 to 7.07; 3 studies, 349 participants; low-certainty evidence). There were no significant differences between ET plus MT and MT alone in fatal/non-fatal strokes in the territory of the treated vertebral artery stenosis after 30 days post-randomisation to completion of follow-up (RR 0.51, 95% CI 0.26 to 1.01; 3 studies, 349 participants; moderate-certainty evidence), ischaemic or haemorrhagic stroke during the entire follow-up period (RR 0.77, 95% CI 0.44 to 1.32; 3 studies, 349 participants; moderate-certainty evidence), death during the entire follow-up period (RR 0.78, 95% CI 0.37 to 1.62; 3 studies, 349 participants; low-certainty evidence), and stroke or transient ischaemic attack (TIA) during the entire follow-up period (RR 0.65, 95% CI 0.39 to 1.06; 2 studies, 234 participants; moderate-certainty evidence). AUTHORS' CONCLUSIONS: This Cochrane Review provides low- to moderate-certainty evidence indicating that there are no significant differences in either short- or long-term risks of stroke, death, or TIA between people with symptomatic vertebral artery stenosis treated with ET plus MT and those treated with MT alone.


Assuntos
Ataque Isquêmico Transitório , Acidente Vascular Cerebral , Insuficiência Vertebrobasilar , Angioplastia/efeitos adversos , Angioplastia/métodos , Humanos , Ataque Isquêmico Transitório/etiologia , Pessoa de Meia-Idade , Stents/efeitos adversos , Acidente Vascular Cerebral/complicações , Insuficiência Vertebrobasilar/complicações , Insuficiência Vertebrobasilar/terapia
8.
Opt Express ; 29(4): 6069-6079, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33726136

RESUMO

Achieving a high Q-factor metamaterial unit for a precision sensing application is highly demanded in recent years, and most of the developed high-performance sensors based on the high-Q metamaterial units are due to the dielectric/magnetic property changes of the substrate/superstrate. In this paper, we propose a completely different sensing metamaterial unit configuration, with good sensing sensitivity and precision properties, based on the thermally tunable liquid metals. Specifically, a basic thermally tunable metamaterial unit, the mercury-inspired split ring resonator (SRR), is firstly presented to theoretically show the magnetic resonance and negative permeability frequency band shift properties under different background temperatures. Then, considering the radiation loss mechanism of the conventional SRR metamaterial unit and based on the physically reliable ability of liquid metals, the modified mercury-inspired Fano and toroidal resonators with a large frequency tuning range and high Q-factor are developed and discussed. The numerical demonstrations have shown that the designed Fano and toroidal resonators have much better sensing precision performances compared to the conventional SRR for the temperature sensing application. The experimental demonstrations have also been used to verify the proposed mercury-based toroidal resonators, and good agreements are achieved.

9.
BMC Nephrol ; 21(1): 495, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33213398

RESUMO

BACKGROUND: Chronic kidney disease (CKD) is a significant public health concern. In patients with CKD, interventions that support disease self-management have shown to improve health status and quality of life. At the moment, the use of electronic health (eHealth) technology in self-management interventions is becoming more and more popular. Evidence suggests that eHealth-based self-management interventions can improve health-related outcomes of patients with CKD. However, knowledge of the implementation and effectiveness of such interventions in general, and in China in specific, is still limited. This study protocol aims to develop and tailor the evidence-based Dutch 'Medical Dashboard' eHealth self-management intervention for patients suffering from CKD in China and evaluate its implementation process and effectiveness. METHODS: To develop and tailor a Medical Dashboard intervention for the Chinese context, we will use an Intervention Mapping (IM) approach. A literature review and mixed-method study will first be conducted to examine the needs, beliefs, perceptions of patients with CKD and care providers towards disease (self-management) and eHealth (self-management) interventions (IM step 1). Based on the results of step 1, we will specify outcomes, performance objectives, and determinants, select theory-based methods and practical strategies. Knowledge obtained from prior results and insights from stakeholders will be combined to tailor the core interventions components of the 'Medical Dashboard' self-management intervention to the Chinese context (IM step 2-5). Then, an intervention and implementation plan will be developed. Finally, a 9-month hybrid type 2 trial design will be employed to investigate the effectiveness of the intervention using a cluster randomized controlled trial with two parallel arms, and the implementation integrity (fidelity) and determinants of implementation (IM step 6). DISCUSSION: Our study will result in the delivery of a culturally tailored, standardized eHealth self-management intervention for patients with CKD in China, which has the potential to optimize patients' self-management skills and improve health status and quality of life. Moreover, it will inform future research on the tailoring and translation of evidence-based eHealth self-management interventions in various contexts. TRIAL REGISTRATION: Clinicaltrials.gov NCT04212923 ; Registered December 30, 2019.


Assuntos
Insuficiência Renal Crônica/terapia , Autogestão , Telemedicina , Interface Usuário-Computador , China , Apresentação de Dados , Humanos , Projetos de Pesquisa , Autogestão/métodos
10.
Angew Chem Int Ed Engl ; 59(13): 5308-5311, 2020 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-31834658

RESUMO

Chitin is one of the most abundant and cheaply available biopolymers in Nature. Chitin has become a valuable starting material for many biotechnological products through manipulation of its N-acetyl functionality, which can be cleaved under mild conditions using the enzyme family of de-N-acetylases. However, the chemoselective enzymatic re-acylation of glucosamine derivatives, which can introduce new stable functionalities into chitin derivatives, is much less explored. Herein we describe an acylase (CmCDA from Cyclobacterium marinum) that catalyzes the N-acylation of glycosamine with a range of carboxylic acids under physiological reaction conditions. This biocatalyst closes an important gap in allowing the conversion of chitin into complex glycosides, such as C5-modified sialosides, through the use of highly selective enzyme cascades.


Assuntos
Amidoidrolases/metabolismo , Quitina/química , Glucosamina/química , Glicosídeos/síntese química , Açúcares Ácidos/síntese química , Acilação , Amidas/química , Biocatálise , Ácidos Carboxílicos/química , Conformação Molecular , Estereoisomerismo , Açúcares Ácidos/química
11.
Mediators Inflamm ; 2019: 7898095, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31736656

RESUMO

Accumulated evidences show that neuroinflammation play a pivotal role in the pathogenesis of depression. Neuropeptide Y (NPY) and its receptors have been demonstrated to have anti-inflammative as well as antidepressant effects. In the present study, the ability of NPY to modulate depressive-like behaviors induced by lipopolysaccharides (LPS) in rats and the receptors and signaling mechanisms involved were investigated. Continuous injection LPS (i.p) for 4 days led to development of depressive-like behaviors in rats, accompanied with M1-type microglia activation and increased levels of IL-1ß as well as decreased levels of NPY and Y2R expression in the mPFC selectively. Local injection of NPY into the medial prefrontal cortex (mPFC) ameliorated the depression-like behaviors and suppressed the NLRP3 inflammasome signaling pathway. Y2R agonist PYY (3-36) mimicked and Y2R antagonist BIIE0246 abolished the NPY effects in the mPFC. All these results suggest that NPY and Y2R in the mPFC are involved in the pathophysiology of depression and NPY plays an antidepressant role in the mPFC mainly via Y2R, which suppresses the NLRP3 signaling pathway, in LPS-induced depression model rats.


Assuntos
Lipopolissacarídeos/farmacologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Receptores de Neuropeptídeo Y/metabolismo , Animais , Western Blotting , Depressão/metabolismo , Interleucina-1beta/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/efeitos dos fármacos
12.
Med Sci Monit ; 24: 397-404, 2018 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-29352772

RESUMO

BACKGROUND Congenital single-side deafness (SSD) affects sound localization even after cochlear implantation (CI) in some conditions. The medial nucleus of the trapezoid body (MNTB) plays an important role in binaural benefit and sound localization, but little is known about intrinsic molecular changes in MNTB with SSD. We aimed to observe changes in MNTB in early-developmental SSD rats, including the key neurotransmitters (GABA, Gly, Glu) and major receptors (GABAa-R/GABAb-R for GABA, Gly-R for Gly, and AMPA/NMDA for Glu). MATERIAL AND METHODS The model of early-developmental SSD was acquired by right cochlear ablation at P12 and confirmed by ABR. High-performance liquid chromatography fluorescence detection (HPLC-FLD) was performed to measure the levels of neurotransmitters in MNTB. The relative expression of neurotransmitter receptors was tested by quantitative real-time PCR analysis. RESULTS (1) The right MNTB of experimental rats had an increase in GABA, Gly, and Glu at 4 weeks after right cochlear ablation (P<0.05). (2) At 2 weeks, the left MNTB of experimental rats showed increases in GABAa-R, GABAb-R, Gly-R, and AMPA, while the right MNTB showed lower expression of NMDA (P<0.05). The higher receptors in left MNTB decreased to a level at which we found no difference at 1 week for GABAa-R and GABAb-R (P>0.05), and was even reversed for Gly-R and AMPA (P<0.05). (3) Gly level was significantly increased at 2 weeks bilaterally and continued to 4 weeks in the left MNTB (P<0.05). CONCLUSIONS Early-developmental SSD can lead to asymmetric distribution of neurotransmitters and receptors in MNTB, which can be the fundamental cause of defective sound localization after cochlear implantation.


Assuntos
Surdez/metabolismo , Neurotransmissores/fisiologia , Receptores de Neurotransmissores/fisiologia , Potenciais de Ação , Animais , Surdez/fisiopatologia , Feminino , Masculino , Neurotransmissores/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de GABA/metabolismo , Receptores de Neurotransmissores/metabolismo , Corpo Trapezoide/citologia , Corpo Trapezoide/fisiologia , Ácido gama-Aminobutírico/metabolismo
13.
Plant Mol Biol ; 87(3): 219-33, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25539982

RESUMO

Most land plants have a wax layer which covers their aerial parts to protect them from environmental stresses, such as drought, UV radiation, and pathogenic invasion. The wax biosynthesis has been well studied previously in Arabidopsis, but it still remains elusive in cucumber. Here, we isolated a CER1 homolog CsCER1 in cucumber, and we found that the expression of CsCER1 in the cucumber line 3401 which shows waxy fruit phenotype is much higher than that in the cucumber line 3413 which displays glossy fruit phenotype. Spatial and temporal expression analyses revealed that CsCER1 is specifically expressed in the epidermis where waxes are synthesized, and sub-cellular location showed that CsCER1 protein is localized to the endoplasmic reticulum. The expression of CsCER1 can be induced by low temperature, drought, salt stress and abscisic acid. In addition, abnormal expressions of CsCER1 in transgenic cucumber plants have dramatic effects on very-long-chain (VLC) alkanes biosynthesis, cuticle permeability, and drought resistance. Our data suggested that CsCER1 plays an important role in VLC alkanes biosynthesis in cucumber.


Assuntos
Alcanos/metabolismo , Cucumis sativus/genética , Cucumis sativus/fisiologia , Genes de Plantas , Aclimatação/genética , Aclimatação/fisiologia , Alcanos/química , Sequência de Aminoácidos , Arabidopsis/genética , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Secas , Expressão Gênica , Dados de Sequência Molecular , Permeabilidade , Fenótipo , Filogenia , Epiderme Vegetal/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia , Interferência de RNA , Homologia de Sequência de Aminoácidos , Ceras/química , Ceras/metabolismo
14.
Plant Cell Physiol ; 56(7): 1339-54, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26023108

RESUMO

Cuticular waxes play an important part in protecting plant aerial organs from biotic and abiotic stresses. In previous studies, the biosynthetic pathway of cuticular waxes and relative functional genes has been researched and understood; however, little is known in cucumber (Cucumis sativus L.). In this study, we cloned and characterized an AtWAX2 homolog, CsWAX2, in cucumber and found that it is highly expressed in the epidermis, where waxes are synthesized, while subcellular localization showed that CsWAX2 protein is localized to the endoplasmic reticulum (ER). The transcriptional expression of CsWAX2 was found to be induced by low temperature, drought, salt stress and ABA, while the ectopic expression of CsWAX2 in an Arabidopsis wax2 mutant could partially complement the glossy stem phenotype. Abnormal expression of CsWAX2 in transgenic cucumbers specifically affected both very long chain (VLC) alkanes and cutin biosynthesis. Furthermore, transgenic cucumber plants of CsWAX2 showed significant changes in pollen viability and fruit resistance to water loss and pathogens compared with the wild type. Collectively, these results indicated that CsWAX2 plays a pivotal role in wax biosynthesis, influencing pollen fertility and the plant's response to biotic and abiotic stresses.


Assuntos
Cucumis sativus/genética , Proteínas de Plantas/genética , Pólen/genética , Ceras/metabolismo , Ácido Abscísico/farmacologia , Adaptação Fisiológica/genética , Sequência de Aminoácidos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Cucumis sativus/metabolismo , Secas , Fertilidade/genética , Regulação da Expressão Gênica de Plantas , Teste de Complementação Genética , Dados de Sequência Molecular , Mutação , Filogenia , Epiderme Vegetal/genética , Epiderme Vegetal/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Proteínas de Plantas/classificação , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Pólen/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos , Cloreto de Sódio/farmacologia , Estresse Fisiológico , Temperatura
15.
J Exp Bot ; 65(12): 3201-13, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24790111

RESUMO

Cucumber (Cucumis sativus L.) is a typical monoecious vegetable with individual male and female flowers, and has been used as a model plant for sex determination. It is well known that sex differentiation of cucumber can be regulated by phytohormones, such as gibberellic acid (GA) and ethylene. The molecular mechanism of female sex expression modulated by ethylene has been widely understood, but how GA controls male sex expression remains elusive. In hermaphroditic Arabidopsis and rice, GA can regulate stamen and anther development via the transcriptional regulation of GAMYB. Here we characterized a GAMYB homologue CsGAMYB1 in cucumber. We found that CsGAMYB1 is predominantly expressed in male flower buds, where its expression is upregulated by GA3 treatment. CsGAMYB1 protein is localized in the nucleus. CsGAMYB1 can partially rescue stamen development and fertility phenotypes of an Arabidopsis myb33 myb65 double mutant. However, constitutive overexpression of CsGAMYB1 in wild-type Arabidopsis resulted in male sterility, which mimics the effect of GA overdose in flower development. Knockdown of CsGAMYB1 in cucumber decreases the ratio of nodes with male and female flowers, and ethylene is not involved in this process. Our data suggest that CsGAMYB1 regulates sex expression of cucumber via an ethylene-independent pathway.


Assuntos
Cucumis sativus/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Fatores de Transcrição , Sequência de Aminoácidos , Arabidopsis/genética , Arabidopsis/metabolismo , Cucumis sativus/metabolismo , Etilenos/metabolismo , Giberelinas/metabolismo , Dados de Sequência Molecular , Filogenia , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Alinhamento de Sequência , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
16.
Front Neurol ; 15: 1369836, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628695

RESUMO

Background: The recovery of upper extremity motor impairment after stroke remains a challenging task. The clinical effectiveness of repetitive transcranial magnetic stimulation (rTMS), which is believed to aid in the recovery process, is still uncertain. Methods: A systematic search was conducted in Medline (Ovid), Cochrane and Embase electronic databases from March 28, 2014, to March 28, 2023. The inclusion criteria consisted of randomized controlled trials that assessed the effects of rTMS on the recovery of upper limb motor impairment among stroke patients. Various measurements, including the Fugl Meyer Assessment Upper Extremity Scale (FMA-UE), Brunnstrom recovery stage, Action Research Arm Test (ARAT), and Barthel index, were evaluated both before and after the intervention. Results: Nineteen articles with 865 patients were included. When considering only the rTMS parameters, both inhibitory and excitatory rTMS improved FMA-UE (MD = 1.87, 95% CI = [0.88]-[2.86], p < 0.001) and Barthel index (MD = 9.73, 95% CI = [4.57]-[14.89], p < 0.001). When considering only the severity of upper limb hemiplegia, both less severe (MD = 1.56, 95% CI = [0.64]-[2.49], p < 0.001) and severe (MD = 2.05, 95% CI = [1.09]-[3.00], p < 0.001) hemiplegia benefited from rTMS based on FMA-UE. However, when considering the rTMS parameters, severity of hemiplegia and stroke stages simultaneously, inhibitory rTMS was found to be significantly effective for less severe hemiplegia in the acute and subacute phases (MD = 4.55, 95% CI = [2.49]-[6.60], p < 0.001), but not in the chronic phase based on FMA-UE. For severe hemiplegia, inhibitory rTMS was not significantly effective in the acute and subacute phases, but significantly effective in the chronic phase (MD = 2.10, 95% CI = [0.75]-[3.45], p = 0.002) based on FMA-UE. Excitatory rTMS was found to be significantly effective for less severe hemiplegia in the acute and subacute phases (MD = 1.93, 95% CI = [0.58]-[3.28], p = 0.005) based on FMA-UE. The improvements in Brunnstrom recovery stage and ARAT need further research. Conclusion: The effectiveness of rTMS depends on its parameters, severity of hemiplegia, and stroke stages. It is important to consider all these factors together, as any single grouping method is incomplete.

17.
ChemSusChem ; : e202400771, 2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39073228

RESUMO

Conjugated polymers (CPs) have shown promising potential in the field of hydrogen peroxide (H2O2) photosynthesis. However, a deeper understanding of the interactions between building units and specific functional groups within the molecular skeleton is necessary to elucidate the mechanisms driving H2O2 generation. Herein, a series of typical donor-acceptor (D-A) conjugated polymers (B-B, B-CN, B-DCN) were synthesized by introducing different amounts of cyano groups (-CN) into the molecular skeleton. The strong electron withdrawing properties of cyano can greatly promote the effective separation and transfer of photogenerated charges between building units, resulting in an impressive efficiency of H2O2 generation (2128.5 µmol g-1 h-1) for B-DCN, representing a 96-fold enhancement compared to B-B. More importantly, experimental results and theoretical calculations further revealed that the introduction of -CN can markedly reduce the adsorption energy (Ead) of O2, while serving as an active site to induce the conversion of crucial intermediate superoxide anions (.O2-) into singlet oxygen (1O2), achieving dual-channel H2O2 generation (O2→.O2-→H2O2, O2→.O2-→1O2→H2O2). This work provides valuable insights into the design of efficient H2O2 photosynthesis materials.

18.
Infect Drug Resist ; 16: 4929-4941, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37546369

RESUMO

Purpose: Infections induced by multidrug-resistant (MDR) pathogens are one of the most common and serious complications in extracorporeal membrane oxygenation (ECMO) patients. However, there is currently little research about "ECMO and MDR bacteria". The purpose of our study was to clarify the epidemiological characteristics of MDR bacteria and provide references for empiric antibiotic treatments according to the drug susceptibility tests for ECMO patients. Patients and Methods: There were 104 patients admitted to our department and receiving ECMO treatments between January 2014 and December 2022. Altogether, 61 veno-arterial ECMO (VA-ECMO) and 29 veno-venous ECMO (VV-ECMO) patients enrolled. The data on other intensive care unit (ICU) patients in our department in the same period are summarized. Results: A total of 82 MDR bacteria were detected from ECMO patients, and most of these were MDR Gram-negative bacteria (MDR-GNB). There were also 5559 MDR-GNB collected from other patients in our department in the same period. We found that the distribution of MDR-GNB in ECMO patients was different from other critical patients. The proportion of Klebsiella pneumoniae (MDR-KP) in VV-ECMO patients was higher than other critical patients (35.1% and 21.3%, respectively). Moreover, the proportions of MDR Acinetobacter baumannii (MDR-AB) of VA-ECMO and VV-ECMO were higher than other critical patients (54.6%, 43.2% and 30.5%, respectively). In addition, MDR-AB and MDR-KP in ECMO patients exhibited higher percentages of drug resistance to possibly appropriate antibiotics for other critical patients, but showed better sensitivity to colistin. Conclusion: Infections induced by MDR-GNB in ECMO patients were serious and exhibited higher degrees of drug resistance compared with other ICU patients. Colistin might be an option to consider if there is no medical contraindication. However, widespread use of broad spectrum antibiotics is something that should be discouraged, and alternative options are being explored.

19.
Plants (Basel) ; 12(2)2023 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-36679013

RESUMO

Bacillus subtilis was applied in peat-based soilless cultivation systems containing a mixed substrate (peat:vermiculite:perlite = 2:1:1, v/v/v) and irrigated by one-strength or four-strength Hoagland's nutrient solution to explore whether it can alleviate inhibition by higher-nutrient solutions (four-strength) and bring benefits to improvements of quality. The results showed that higher-nutrient solutions improved the flavor quality of cucumber fruit; especially, the contents of (E,Z)-2,6-nonadienal and (E)-2-Nonenal were effectively increased, which are the special flavor substances of cucumber. B. subtilis K424 effectively improved growth performance, photosynthetic capacity, vitamin C content, soluble sugars, soluble protein, and total pectin in cucumber under higher nutrition solution conditions. Compared with the higher solution treatment, the bacterial diversity significantly increased, whereas the presence of fungi had no significant difference following the B. subtilis K424 application. Moreover, B. subtilis K424 reduced the relative abundance of Actinomadura and promoted that of the Rhodanobacter, Bacillus, Pseudomonas, Devosiaceae, and Blastobotrys genera. Redundancy analysis showed that Bacillus, Rhodanobacter, and Blastobotrys were positively correlated with the substrate enzyme of sucrase, catalase, and urease. This study provides insight that B. subtilis K424 mitigated the deleterious effects of high levels of nutrition solution on cucumber growth and quality by improving the substrate enzyme, regulating the microbial community structure, and enhancing the photosynthetic capacity.

20.
Acad Radiol ; 30(12): 2834-2843, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37268514

RESUMO

RATIONALE AND OBJECTIVES: Coronary inflammation can alter the perivascular fat phenotype. Hence, we aimed to assess the diagnostic performance of radiomics features of pericoronary adipose tissue (PCAT) in coronary computed tomography angiography (CCTA) for in-stent restenosis (ISR) after percutaneous coronary intervention. MATERIALS AND METHODS: In this study, 165 patients with 214 eligible vessels were included, and ISR was found in 79 vessels. After evaluating clinical and stent characteristics, peri-stent fat attenuation index, and PCAT volume, 1688 radiomics features were extracted from each peri-stent PCAT segmentation. The eligible vessels were randomly categorized into training and validation groups in a ratio of 7:3. After performing feature selection using Pearson's correlation, F test, and least absolute shrinkage and selection operator analysis, radiomics models and integrated models that combined selected clinical features and Radscore were established using five different machine learning algorithms (logistic regression, support vector machine, random forest, stochastic gradient descent, and XGBoost). Subgroup analysis was performed using the same method for patients with stent diameters of ≤ 3 mm. RESULTS: Nine significant radiomics features were selected, and the areas under the curves (AUCs) for the radiomics model and the integrated model were 0.69 and 0.79, respectively, for the validation group. The AUCs of the subgroup radiomics model based on 15 selected radiomics features and the subgroup integrated model were 0.82 and 0.85, respectively, for the validation group, which showed better diagnostic performance. CONCLUSION: CCTA-based radiomics signature of PCAT has the potential to identify coronary artery ISR without additional costs or radiation exposure.


Assuntos
Doença da Artéria Coronariana , Reestenose Coronária , Humanos , Angiografia por Tomografia Computadorizada/métodos , Reestenose Coronária/diagnóstico por imagem , Reestenose Coronária/etiologia , Vasos Coronários , Angiografia Coronária/métodos , Stents , Tecido Adiposo/diagnóstico por imagem , Aprendizado de Máquina , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia
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