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1.
Eur Rev Med Pharmacol Sci ; 27(4): 1398-1412, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36876680

RESUMO

OBJECTIVE: The aging society and the empty nest of the elderly have become issues that cannot be ignored by the Chinese government. Not only does the physical function of the empty-nest elderly (ENE) decline, and the incidence and prevalence of chronic diseases increase significantly, but they are also more likely to have loneliness, low life satisfaction, mental health problems, and even a much greater possibility of suffering from depression than the nonempty-nest elderly, besides the possibility of catastrophic health expenditure (CHE) which is also greatly increased. This paper aims to evaluate the status quo of dilemma and determinants of a vast sample of subjects based on the national level. SUBJECTS AND METHODS: Data were obtained from the latest 2018's data of the China Health and Retirement Longitudinal Study (CHARLS). Under the guidance of Andersen's model of health services utilization, this study clarified the overall and different demographic characteristics and prevalence of CHE among ENE and further built the Logit and Tobit model to explore the determinants of CHE occurrence and its intensity. RESULTS: A total of 7,602 ENE were included in the analysis, and the overall incidence of CHE among them was 21.20%. Poor self-reported health status (OR=2.03, 95% CI: 1.71-2.35), suffering from three or more chronic diseases simultaneously (OR=1.79, 95% CI: 1.42-2.15), low life satisfaction (OR=1.44, 95% CI: 1.20-1.68) and advanced age played the leading role in accounting for its high risk, and its intensity increased 0.0311 (SE=0.005), 0.0234 (SE=0.007), and 0.0178 (SE=0.005), respectively. In contrast, the leading drop in the probability of CHE among ENE was those whose monthly income was over 20,000 CNY (OR=0.46, 95% CI: 0.38-0.55), whose intensity declined 0.0399 (SE=0.005), whose monthly income was between 2,000 and 20,000 CNY (OR=0.78, 95% CI: 0.66-0.90) and whose intensity declined 0.021 (SE=0.005), and who were married during the survey period (OR=0.82, 95% CI: 0.70-0.94). Simultaneously, rural ENE showed more vulnerability and higher risk of CHE when confronted with these factors compared with the urban ones. CONCLUSIONS: More attention should be paid for ENE in China. The priority, including the relevant health insurance or social security measurements, should be further strengthened.


Assuntos
Gastos em Saúde , Aposentadoria , Idoso , Humanos , Estudos Longitudinais , Inquéritos Epidemiológicos , China
2.
Eur Rev Med Pharmacol Sci ; 26(18): 6469-6486, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36196697

RESUMO

OBJECTIVE: In China, rural doctors (RDs) perform crucial health care missions. However, they have received less attention than their colleagues in urban public hospitals. In this specific group, a severe challenge occurs in sync with a high turnover rate and deficient job satisfaction. MATERIALS AND METHODS: This study aims to systematically summarize and evaluate the influencing factors of job satisfaction and turnover intention among Chinese rural doctors. Seven databases, including PubMed, EMBASE, and China National Knowledge Infrastructure (CNKI), were systematically retrieved, and several experts were consulted to acquire holistic publications in this domain. RESULTS: A total of 20 full-text papers and 22,721 samples were included. In addition, 53 influencing factors were evaluated, of which 38 factors may play a significant role. Based on Herzberg's two-factor theory, together with China's cultural tradition and national conditions, we classified these influencing factors into sociodemographic characteristic factors (n=13), incentive factors (n=18), and health care factors (n=22). Meanwhile, we discussed and analyzed the influencing factors of turnover intention and job satisfaction in detail and put forward corresponding measures and suggestions for the government. CONCLUSIONS: We are confident that this research provides a holistic perspective to systematically evaluate the factors influencing the job satisfaction and intention to leave of Chinese rural doctors. Importantly, we hypothesize that the illumination of cases among Chinese rural physicians applies to other countries or regions, which has significant implications for the reformation of the medical system by governments or decision-makers worldwide.


Assuntos
Satisfação no Emprego , Médicos , China , Humanos , Reorganização de Recursos Humanos , População Rural , Inquéritos e Questionários
3.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 57(9): 907-913, 2022 Sep 09.
Artigo em Chinês | MEDLINE | ID: mdl-36097936

RESUMO

Objective: To compare the treatment effect of distraction osteogenesis (DO) and maxillomandibular advancement (MMA) for severe obstructive sleep apnea hypopnea syndrome (OSAHS) patients and to guide clinical decisions about treatment of OSAHS. Methods: Thirty-seven OSAHS patients which accepted maxillomandibular advancement (MMA) or distraction osteogenesis (DO) in Stomatological Hospital of the Department of Maxillofacial Trauma and Orthognathic Surgery, School of Stomatology, The Forth Military Medical University from June 2017 to June 2019 were collected. Their preoperative and postoperative data of cephalometry, polysomnography (PSG), Pittsburgh sleep quality index (PSQI) and Epworth sleepiness scale (ESS) scores were collected and analyzed. With propensity score matching method, the treatment effect of MMA and DO was analyzed and compared. Results: According to the statistics of MMA group, only AHI was correlated with operative successful rate and cure rate. With the increase of AHI, the treatment effect of MMA on OSAHS patients gradually decreased. The cut-off point of AHI as a predictor of MMA treatment failure was 78.2 n/h. All the matched cases were severe OSAHS patients. Statistical analysis showed that the mandibular elongation of DO patients[(24.00±4.39) mm] was significantly more than that of MMA group [(11.20±1.37) mm] (t=-6.11, P<0.001), the improvement of PSG index [including lowest oxygen saturation (LSpO2), longest apnea (LA) and longest hypopnea (LH)] in DO group [LSpO2=(93.40±1.82)%; LA=(18.28±8.32) s; LH=(61.84±32.94) s] was significantly higher than that in the MMA group [LSpO2=(86.00±4.06)%, LA=(64.08±21.78) s, LH=(172.40±30.70) s](t=-3.72, P=0.005; t=4.39, P=0.003; t=5.49, P=0.004). The PSQI and the ESS scores of DO group (PSQI=4.20±0.83; ESS=3.40±1.52) were also significantly better than that of MMA group (PSQI=8.80±2.39, ESS=9.40±2.88)(t=4.07, P=0.001; t=4.12, P=0.002). Conclusions: For severe OSAHS patients, the objective and subjective indicators of DO treatment group showed a better therapeutic effect than that of MMA.


Assuntos
Avanço Mandibular , Osteogênese por Distração , Apneia Obstrutiva do Sono , Humanos , Estudos Retrospectivos , Apneia Obstrutiva do Sono/cirurgia , Resultado do Tratamento
4.
J Phys Condens Matter ; 34(32)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35605598

RESUMO

We investigate the Dirac-cone-like (DCL) topological electronic properties of nematic-like antiferromagnetic (AFM) states of monolayer FeSe and FeTe designed artificially through first-principles calculations and Wannier-function-based tight-binding (WFTB) method. Our calculations reveal most of them have a pair of DCL bands on the Γ-Xline in the Brillouin zone (BZ) near the Fermi level and open a gap of about 20 meV in the absence and presence of spin-orbit coupling (SOC), respectively, similar to the lowest-energy pair-checkerboard AFM FeSe. We further confirm that they are weak topological insulators based on nonzeroZ2and fragile surface states, which are calculated by the WFTB method. For FeSe and FeTe in pair-checkerboard AFM states, we find that the in-plane compression strain in a certain range can give rise to another pair of DCL bands located on the Γ-X' line in the BZ. In addition, the magnetic moments, energies, and Fe-Se/Te distances for various nematic-like AFM configurations are presented. These calculations the combining effect of magnetism and topology in a single material and the understanding of the superconducting phenomena in iron-based FeSe and FeTe.

5.
J Eur Acad Dermatol Venereol ; 36(5): e386-e387, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35030275
6.
Ultrasonics ; 121: 106656, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34995848

RESUMO

This work focuses on the propagation of surface magnetoelastic waves in a inhomogeneous structure containing ferromagnetic layer of smooth and slowly variable thickness. The dispersion relation of magnetoelastic waves and the wave attenuation due to the thickness variation in the studied structure were analytically obtained. We found that the magnetoelastic resonance frequency is changed at different positions in this structure. Then proposed the idea of modifying the magnetic field to control the magnetoelastic resonance region, and finally considered the possible applications of this structure for signal processing.

8.
J Phys Condens Matter ; 34(8)2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34794129

RESUMO

We investigated magnetic field effect on the topological properties of transition metal dichalcogenide Dirac semimetals (DSMs) PdTe2/PtTe2/PtSe2based on Wannier-function-based tight-binding (WFTB) model obtained from first-principles calculations. The DSMs PdTe2/PtTe2/PtSe2undergo a transition from DSMs into Weyl semimetals with four pairs of Weyl points (WPs) in the entire Brillouin zone by splitting Dirac points under external magnetic fieldB. The positions and energies of WPs vary linearly with the strength of theBfield under thec-axis magnetic fieldB. Under thea- andb-axisBfield, however, the positions of magnetic-field-inducing WPs deviate slightly from thecaxis, and theirkzcoordinates and energies change in a parabolic-like curve with the increasingBfield. However, the system opens an axial gap on theA-Γ axis, and the gap changes with the direction of theBfield when the out ofc-axisBfield is applied. When we further apply the magnetic field in theac,bc, andabplanes, the results are more diverse compared to the axial magnetic field. Under theacandbcplaneBfield, thekzand energies of WPs within angleθ= [0°, 90°] andθ= [90°, 180°] are mirror symmetrically distributed. The distribution of WPs shows broken rotational symmetry under theabplaneBfield due to the difference of non-diagonal part of Hamiltonian. Our theoretical findings can provide a useful guideline for the applications of DSM materials under external magnetic field in the future topological electronic devices.

9.
Zhonghua Yu Fang Yi Xue Za Zhi ; 55(10): 1196-1202, 2021 Oct 06.
Artigo em Chinês | MEDLINE | ID: mdl-34706504

RESUMO

Objective: To explore the effect of long-term exposure to ambient particulate matter (PM10) on the prevalence of diabetes and fasting plasma glucose (FPG). Methods: The subjects of the study were from the baseline population of "Jinchang Cohort", and 24 285 subjects were finally included after excluding incomplete home address information and diabetic diagnosis information. The demographic characteristics, lifestyle and health status of the survey subjects were collected through questionnaire, physical examination and laboratory tests. ArcGIS software was used to match the nearest environmental monitoring stations for each subject according to residential address. Two-year average concentrations of PM10 were calculated to estimate exposure level. The logistic regression and the multiple linear regression were conducted to assess the effects of ambient PM10 on the prevalence of diabetes and FPG. The restricted cubic spline was used to quantify the dose-response relationship. Stratified analysis and effect modification analysis were also performed. Results: The age of 24 285 participants was (49.32±8.60) years, and the BMI was (24.22±6.09) kg/m2. There were 13 950 (57.44%) males and 2 066 (8.51%) diabetic patients. After adjusting for confounders, for every 10 µg/m3 increase in the average PM10 concentration in the first two years of the survey, the prevalence of diabetes increased [OR (95%CI) =1.05 (1.01-1.09)]and the FPG level elevated [ß (95%CI) = 0.061 (0.047-0.076) mmol/L]. The results of the restricted cubic spline analysis showed a nonlinear relationship between PM10 concentration and FPG level (P<0.001). Further subgroup analysis showed that female [OR (95%CI) =1.10 (1.03-1.18)], people over 50 years old [OR (95%CI) =1.06 (1.02-1.11) ], subjects with family history of diabetes [OR (95%CI) = 1.13 (1.04-1.23) ], and with hypertension [OR (95%CI) = 1.07 (1.02-1.12) ] had a stronger association between the prevalence of diabetes and PM10 exposure (all P interaction values were<0.05). The effects of PM10 on FPG were more significant in people older than 50 years[ß (95%CI) = 0.080 (0.050-0.109) mmol/L], with family history of diabetes [ß (95%CI) = 0.087 (0.036-0.137) mmol/L], and hypertension [ß (95%CI) = 0.077 (0.046-0.108) mmol/L] (all P interaction values were<0.05). Conclusions: Long-term exposure to ambient PM10 increases the diabetes prevalence and FPG. People older than 50 years old, with family history of diabetes and hypertension could be more sensitive to the effects of PM10 exposure.


Assuntos
Poluentes Atmosféricos , Diabetes Mellitus , Adulto , Poluentes Atmosféricos/análise , Glicemia/análise , Diabetes Mellitus/epidemiologia , Exposição Ambiental/análise , Jejum , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Material Particulado/análise , Prevalência
10.
Phys Rev Lett ; 126(24): 242301, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34213947

RESUMO

Using combined data from the Relativistic Heavy Ion and Large Hadron Colliders, we constrain the shear and bulk viscosities of quark-gluon plasma (QGP) at temperatures of ∼150-350 MeV. We use Bayesian inference to translate experimental and theoretical uncertainties into probabilistic constraints for the viscosities. With Bayesian model averaging we propagate an estimate of the model uncertainty generated by the transition from hydrodynamics to hadron transport in the plasma's final evolution stage, providing the most reliable phenomenological constraints to date on the QGP viscosities.

11.
Int J Infect Dis ; 105: 349-350, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33607303

RESUMO

Cutaneous secondary syphilis presents with various manifestations, including condyloma lata (confluented moist papules). This article reports an unusual case of oral condyloma lata. A 56-year-old man presented with a 2-month history of foreign body sensation and sore throat. Physical examination revealed a hypertrophic, reddish-brown, flat-topped, moist plaque in the right amygdaloid fossa. This raised clinical suspicion of lymphoma. However, further enquiry revealed that the patient had extramarital sexual history with a female sex worker. Rapid plasma regain and Treponema pallidum particle agglutination tests were both positive. The patient's wife was diagnosed with early latent syphilis. Both the patient and his wife were treated with penicillin G benzathine, and the lesion in the male patient disappeared in 2 weeks. To the authors' knowledge, a single condyloma lata in the amygdaloid fossa mimicking lymphoma has not been reported previously. Awareness of the usual manifestations of syphilis can avoid unnecessary biopsy, and early diagnosis and treatment may prevent irreversible complications. Partner notification is very important to reduce the risk of transmission, and persistent or recurrent infection.


Assuntos
Condiloma Acuminado/etiologia , Doenças da Boca/etiologia , Sífilis Cutânea/complicações , Sífilis/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Penicilina G Benzatina/uso terapêutico , Profissionais do Sexo , Sífilis Cutânea/tratamento farmacológico
12.
Animal ; 15(3): 100167, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33495095

RESUMO

Taurine has been considered as an essential nutrient for many aquaculture species. While dietary taurine supplementation is highly recommended, novelty studies on taurine metabolism in fish are needed. The present study aimed to provide insight into the molecular mechanisms involved in multiple metabolome changes in Nile tilapia (Oreochromis niloticus) by studying plasma metabolic profile changes in response to graded levels of dietary taurine supplementation. The analysis used proton nuclear magnetic resonance-based metabolomics. Four groups of tilapias were fed with four diets supplemented with 0.0, 0.4, 0.8 and 1.2% taurine for 84 days. Fish plasma was sampled at multiple time points to provide an accurate snapshot of specific metabolic profiles during growth. Under the effect of taurine supplementation, 21 and 12 metabolites in tilapia plasma shown significant changes in terms of time-dependence and diet-dependence, respectively. These metabolic changes in tilapia plasma were mainly associated with energy and amino acid metabolism, lipids, nucleotides and protein metabolism. The results indicate that 0.8% taurine supplementation could significantly improve the carbohydrate synthesis, protein digestion and absorption, and fat deposition of tilapia and thereby promoted growth and development of tilapia.


Assuntos
Ciclídeos , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais , Metaboloma , Plasma , Taurina
14.
Plant Biol (Stuttg) ; 22(6): 1113-1122, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32530558

RESUMO

Drought is one of the major stress factors in wheat production on a global scale. Drought priming during the early growth stage can enhance drought tolerance in wheat (Triticum aestivum L.). Abscisic acid (ABA) and hydrogen peroxide (H2 O2 ) are important signal molecules in the adaptation of plants to drought stress. However, the roles of ABA and H2 O2 in drought priming-induced drought tolerance are not clear. In the present study, we evaluated the responses of wheat to an ABA inhibitor, H2 O2 scavenger and an inhibitor to investigate the (i) relationship between ABA and H2 O2 in osmotic adjustment after drought priming in the vegetative stage and (ii) responses to drought stress during grain filling. In the drought priming alone treatments, chemical application resulted in the scavenging of ABA and H2 O2 , weakening the alleviation effects of drought priming on drought stress, as demonstrated by the lower leaf water potential and grain yield. The ABA inhibitor completely inhibited accumulation of ABA and H2 O2 ; the ABA inhibitor inhibited respiratory burst oxidase homologue expression, whereas the H2 O2 inhibitor resulted in higher 9-cis-epoxycarotenoid dioxygenase expression and ABA concentration in primed plants, indicating that ABA scavenging inhibited H2 O2 biosynthesis while H2 O2 scavenging did not inhibit ABA biosynthesis. The results further demonstrated that NADPH oxidase-mediated H2 O2 production functions downstream of ABA, which induces osmolyte transcript expression and accumulation, and thus contributes to drought priming-induced stress tolerance. These results provide a theoretical basis for a better understanding of the mechanisms involved in drought priming-induced tolerance in wheat plants.


Assuntos
Ácido Abscísico , Adaptação Fisiológica , Secas , Peróxido de Hidrogênio , Triticum , Ácido Abscísico/metabolismo , Adaptação Fisiológica/efeitos dos fármacos , Sequestradores de Radicais Livres/farmacologia , Herbicidas/farmacologia , Peróxido de Hidrogênio/metabolismo , Piridonas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Tioureia/análogos & derivados , Tioureia/farmacologia , Triticum/efeitos dos fármacos , Triticum/fisiologia
15.
Zhonghua Xin Xue Guan Bing Za Zhi ; 48(3): 223-227, 2020 Mar 24.
Artigo em Chinês | MEDLINE | ID: mdl-32234180

RESUMO

Objective: To investigate the relationship between high sensitivity C-reactive protein (hs-CRP) level and incidence of left atrial spontaneous echocardiographic contrast (LASEC) in the patients with nonvalvular atrial fibrillation (AF). Methods: Four hundred and ninety consecutive patients with nonvalvular atrial fibrillation who underwent radiofrequency ablation for the first time from January 1, 2018 to June 30, 2018 in the Department of Cardiology, Beijing Anzhen Hospital were enrolled. According to the results of transesophageal echocardiography before radiofrequency ablation, patients were divided into the group without LASEC (n=338) and the group with LASEC (n=152). hs-CRP was determined by latex enhanced immunoturbidimetry. The relationship between hs-CRP and LASEC in patients with nonvalvular atrial fibrillation was investigated by univariate and multivariate logistic analysis. Results: LASEC was detected in 152 (31%) of 490 patients. Significant differences in age, type of atrial fibrillation, previous embolic events, fibrinogen, D-dimer, the left atrial anteroposterior diameter and CHA(2)DS(2)-VASc scores were found between patients with and without LASEC (all P<0.05). Compared with the group without LASEC, the serum hs-CRP level was significantly higher in the group with LASEC (3.16 (1.30, 5.23) mg/L vs. 0.67 (0.37, 1.48) mg/L, P<0.001). Multivariate logistic regression analysis showed that hs-CRP (OR=1.136, 95%CI 1.060 - 1.217, P<0.001) and D-dimer (OR=1.040, 95%CI 1.011 - 1.070, P=0.007) were independent determinants for LASEC in this patient cohort. Conclusions: hs-CRP is an independent determinant for LASEC in patients with nonvalvular atrial fibrillation. Inflammation may thus be involved in the formation of prethrombotic state in patients with nonvalvular atrial fibrillation.


Assuntos
Fibrilação Atrial , Apêndice Atrial , Fibrilação Atrial/epidemiologia , Proteína C-Reativa , Ecocardiografia Transesofagiana , Eletrocardiografia , Átrios do Coração , Humanos , Incidência , Fatores de Risco
16.
QJM ; 113(9): 689-690, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31909798
17.
Nanotechnology ; 31(9): 095502, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-31675732

RESUMO

Flexible photodetector shows great potential applications in intelligent wearable devices, health monitoring, and biological sensing. In this work, single crystal ß-tellurium nanowires were grown on flexible muscovite by molecular beam epitaxy, constructing high-density ordered nanomesh structure. The prepared photodetectors based on tellurium nanomesh exhibit excellent mechanical flexibility, fast response in a broad range from ultraviolet to near-infrared, and good photosensitivity. We found that the flexible photodetectors with Shottky contact drastically suppressed dark current, while the response speed was lowered in comparison to the devices with ohmic contact, as holes would take a long time to tunnel through the Shottky barrier between metal and p-type Te. Moreover, the photoresponse of flexible Shottky photodetectors can be modulated by piezoelectricity of tellurium, and pronounced photocurrent increase after bending many times. Under external stress, polarization charges could tune Shottky barrier height of the metal/tellurium, resulting in variation of photocurrent. This research not only explores the broadband photoresponse and piezoelectric effect of tellurium nanomesh, but also promotes the integration and development of broadband flexible optoelectronic devices.

19.
Beijing Da Xue Xue Bao Yi Xue Ban ; 51(3): 525-529, 2019 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-31209426

RESUMO

OBJECTIVE: To quantitatively analyze image quality of two sets of phantom (CatPhan504 and Cheese) Megavoltage computed tomography (MVCT) images acquired by Helical Tomotherapy with three scanning modes (Fine, Normal and Coarse), and to explore and validate a semi-automatic quality assurance procedure for MVCT images of Helical Tomotherapy. METHODS: On Helical Tomotherapy, CatPan504 and Cheese phantoms were scanned with three pitch levels (Fine, Normal, Coarse: 4 mm, 8 mm, 12 mm/circle) respectively. Pylinac, Matlab and Eclipse were used to calculate and compare spatial resolution, noise level and low contrast resolution of images obtained under three scanning modes respectively. The spatial resolution can be evaluated by the blurring of line-pair CT value in the images of CatPhan504's CTP528 module. The noise level can be evaluated by the integral non-uniformity in the images of Cheese's uniformity module. the low contrast resolution can be evaluated by contrast-to-noise ratio of both phantoms' plug-in module, or visibility of the region of interest (Supra-Slice) in the images of CatPhan504's CTP515 module. RESULTS: Analyses on CatPhan504's line pair module(CTP528 module) showed that the first three line pairs(the gap size are 0.500 cm, 0.250 cm and 0.167 cm respectively) could be clearly observed but blurring began to occur from the fourth line pair(the gap size is 0.125 cm) under Coarse mode. Meanwhile, the first four line pairs were all observable under the Normal and Fine modes. Integral non-integrity index(the value negatively correlated with the noise level) were 0.155 7, 0.136 8 and 0.122 9 for Coarse, Normal and Fine modes respectively. None of the Supra-Slice in CatPhan504's CTP515 module could be observed under three imaging modes. Low contrast contrast-to-noise ratio of Cheese phantom was similar under three modes and the insert visibility exhibited nearly linear growth with the increasing difference between CT average value of the insert material and background. CONCLUSION: Superiority and inferiority of three image modes in terms of the three image quality index was not consistent. Evaluation results above could provide reference for more rational decision on scanning modes selection of helical tomotherapy, which was based on image visualization demands in clinical practice. The proposed method could also provide guidance for similar image quality assessment and periodic quality assurance.


Assuntos
Radioterapia de Intensidade Modulada , Tomografia Computadorizada de Feixe Cônico , Imagens de Fantasmas , Tomografia Computadorizada Espiral , Tomografia Computadorizada por Raios X
20.
Plant Biol (Stuttg) ; 21(5): 813-824, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30977948

RESUMO

Chilling and lodging are major threats to wheat production. However, strategies that can be used to effectively mitigate the adverse effects of these threats are still far from clear. Mechanical wounding is a traditional agronomic measure, whereas information about the role it plays in wheat chilling and lodging is scant. The aim of the present study was to investigate mechanisms underlying the protective roles of mechanical wounding in alleviating damage from chilling at jointing stage and enhancing lodging resistance after anthesis of winter wheat (Triticum aestivum L.). Our data show that net photosynthesis rate, maximum photochemical efficiency of photosystem II, activity of the antioxidant enzymes and osmolytes were significantly increased in the latest fully expanded leaves of wounded plants under chilling. Wounding also reduced hydrogen peroxide accumulation, electrolyte leakage and water loss in wounded plants. Moreover, mechanical wounding significantly reduced the length but increased the diameter and wall thickness of the basal second internode of the main stem. Quantitative and histochemical analysis further indicated that wounding increased lignin accumulation and activity of enzymes involved in lignin synthesis, which resulted in increased mechanical strength and the lodging resistance index in the main stem. We conclude from our data that mechanical wounding confers both cold tolerance by alleviating the damage caused by chilling at jointing stage and lodging resistance after anthesis of wheat plants.


Assuntos
Triticum/fisiologia , Clorofila/metabolismo , Resposta ao Choque Frio , Produção Agrícola , Fotossíntese , Complexo de Proteína do Fotossistema II/metabolismo , Caules de Planta/crescimento & desenvolvimento , Estresse Fisiológico , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
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