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Objective@#To explore the characteristics and related factors of adolescent executive function, so as to provide theoretical basis for promoting the development of adolescent executive function.@*Methods@#A total of 5 018 adolescents aged 13-18 from Shanghai, Suzhou, Taiyuan, Wuyuan, Xingyi and Urumqi were selected by convenient cluster random sampling method from September to December 2022, and their basic information, family status, lifestyle behavior, physical fitness and executive function were investigated by questionnaire survey. Considering the heterogeneity between schools, a multilevel Logistic model was established to analyze the related factors of adolescent executive function.@*Results@#The inhibitory function of high school students was better than that of middle school students (Z=-2.69). In terms of refreshment function, high school students were superior than middle school students (1-back:Z=-11.32; 2-back:Z=-11.36), and male students were superior than female students (2-back:Z=-2.18); in terms of shifting function, high school students were superior than middle school students (Z=-2.63), and boys were superior than girls (Z=-7.10)(P<0.05). The results of multilevel model analysis showed that the executive function of adolescents was clustered at the school level. At the individual level, junior high school refreshment function (1-back:β=56.94; 2-back:β=127.00), and shifting function (β=35.64) were worse than that of high school students; the refreshment function 2-back (β=-21.24) and shifting function (β=-28.42) of male students were better than those of female students; the refreshment function 2-back of nononly child was better than that of only child (β=-19.36); refreshment function of low fitness was worse than that of high fitness (β=37.35); the shifting function of the video screen time not up to standard was better than that of the standard (β=-14.30)(P<0.05).@*Conclusions@#The executive function of high school students is better than that of middle school students, the refreshment function and shifting function of boys are better than that of girls. Family environment, lifestyle and physical health are significant factors related to executive function of Chinese adolescents. By raising awareness of the major supporting and impeding factors for executive functioning in adolescents, it can help to develop effective intervention programs for adolescents.
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Objective@#To explore of executive function in obese adolescents, so as to provide a reference for executive function enhancement intervention in obese adolescents.@*Methods@#A convenience sample of 1 227 adolescents aged 13-18 years was selected from 2 secondary schools in Taiyuan City during March-April 2023. The Flanker task, N-back task and More odd shifting task was used to compare the different subfunctions of executive function (refreshing function, shifting function, inhibiting function) of 61 obese adolescents and 70 normal weight adolescents. Independent samples t-tests was used for between group comparisons and Cohen s d -tests was used to calculate between group differences in executive function between the two groups of adolescents.@*Results@#Compared with the group of normal weight, time responses of the inhibitory function [(29.73±19.55)ms], the refreshing function [1-back: (1 088.75±275.76)ms, 2-back:( 1 285.44± 355.16)ms] and the shifting function [(380.34±153.18) ms] in the obese group were significantly longer than those in the normal weight group [(14.86±20.27, 888.38±286.57, 1 126.20± 287.43 , 323.12±134.71) ms] ( t =4.26, 4.06, 1.92,2.26, P < 0.05 ); inhibitory function (0.91±0.09) and 1-back (0.73±0.24) were also significantly less correct than in the normal weight group (0.94±0.05, 0.83±0.21) ( t =-2.04, -2.04, P <0.05). Obese adolescents showed moderate adverse effect sizes in the inhibition function ( d =0.746,0.712) and the refresh function 1-back, and smaller adverse effect sizes in the refresh function 2-back and the conversion function( d =0.497,0.398).@*Conclusion@#Obese adolescents have significant executive function deficits, but the degree of adverse varies across sub-functions, with inhibitory function being the core deficit component of executive function in obese adolescents.
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Objective@#To explore the relationship between cardiorespiratory fitness and executive function in Chinese adolescents, so as to provide a reference for promoting the overall development of Chinese adolescents physical and mental health.@*Methods@#From September to December 2022, a total of 5 018 adolescents aged 13 to 18 years from Shanghai, Suzhou, Taiyuan, Wuyuan, Xingyi, and Urumqi were selected by stratified cluster sampling method to assess cardiorespiratory fitness and executive function. Pearson s correlation and linear hierarchical regression were performed to analyze the relationship between cardiorespiratory fitness and executive functions.@*Results@#Among the sample of adolescents, maximal oxygen consumption (VO 2max ) was negatively correlated with the refreshing(1-back, 2-back) and conversion executive function responses ( r=-0.07, -0.12, -0.12, P <0.01). Linear regression analysis showed that VO 2max was negatively correlated with the reaction times of the refreshing(1-back, 2-back) and conversion functions ( B=-2.99, -6.44, -1.69, P <0.01).@*Conclusions@#Higher cardiorespiratory fitness among adolescents is associated with better performance in executive function. Teenagers should strengthen high intensity cardiopulmonary endurance exercise to promote the improvement of executive function.
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Abstract@#Executive function is an advanced cognitive process aimed at the flexible coordination, optimization, and control of the cognitive processes of task solving in order to accomplish a specific task, ensuring that the individual produces effective behaviors, including inhibitory control, working memory, and cognitive flexibility. Given the sensitivities and specificities that characterize an individual s physical and mental development during adolescence, this period is critical for the development of executive function in adolescents. In the paper, the influencing factors of adolescents executive function development are systematically described from three dimensions, namely, biology, environment and lifestyle; by analyzing the mechanisms and differences in the effects of different influencing factors, this editorial provides a scientific basis for adolescents executive function improvement and intervention.
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Objective@#To explore the correlation between different nutritional status and depressive symptoms among adolescents, so as to provide a theoretical basis for targeted improvement of nutritional status and depressive symptoms in adolescents.@*Methods@#A total of 8 102 adolescents aged 12-17 years in Shanghai, Urumqi, Changsha and Kunming were selected by random cluster sampling. Depressive symptoms were assessed by the Center for Epidemiologic Studies Depression Scale(CES-D). Height and weight were measured. Kruskal Wallis H test, Chi square test and ordinal Logistic regression were used to analyze the relationship between nutritional status and depressive symptoms in adolescents.@*Results@#The overall detection rate of depressive symptoms in adolescents was 25.6%, with girls (30.1%) higher than that of boys (21.1%) ( χ 2=87.60, P <0.01). There were statistically significant differences in the scores of depressive symptoms among girls with different nutritional status ( Z =8.34, P <0.05). The detectable rate of depressive symptoms increased with BMI among girls( χ 2 trend =6.04, P <0.05). After controlling for confounding factors, ordinal Logistic regression showed that the obese girls had higher risks in depressive symptoms detection compared with normal weight girls ( OR=1.45, 95%CI=1.10-1.91, P <0.05).@*Conclusion@#The nutritional status of girls is better than boys, but the prevalence of depressive symptoms is higher than boys. The risk of depressive symptoms in girls increases with BMI.
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Objective@#To explore the relationship between adolescents physical fitness and depressive symptoms, and to provide reference for the early prevention and intervention of depressive symptoms and improvement of physical fitness in Chinese adolescents.@*Methods@#From September to December 2021, a total of 8 102 adolescents were selected by random cluster sampling method in Shanghai, Urumqi, Changsha and Kunming. The Center for Epidemiologic Studies Depression Scale(CES-D) was used to investigate the depressive symptoms, and completed grip strength, standing long jump, 50 m running, modified sitting forward flexion, 20 s repeated traverse, 30 s sit ups, 20 m round trip running (20 m SRT) test. χ 2 test, Goodman Kruskal Gamma and Logistic regression analysis were used to analyze the relationship between physical fitness index(PFI) and depressive symptoms.@*Results@#The overall detection rate of depressive symptoms in adolescents with high level PFI was 23.4%, and the detection rate of low level adolescents was 26.3%, with a statistically significant difference ( χ 2=6.73, P =0.01). There was a significant positive correlation between PFI and depressive symptoms in the high school group ( G=0.09, P <0.05) and the boy group ( G=0.12, P < 0.05 ), and there was no significant association between PFI and depressive symptoms in the junior high school group and the girl group ( P >0.05). After adjusting for gender and age in the Logistic regression model, compared with those with high PFI, the risk of depressive symptoms in those with low PFI was 1.18 times (95% CI =1.05-1.33).@*Conclusion@#There is a correlation between physical fitness and depressive symptoms in adolescents. Adolescents with low PFI are at higher risk of developing depressive symptoms than those with high PFI.
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Objective@#To explore the correlation between non suicidal self injury(NSSI) behaviors and depressive symptoms in adolescents and to provide a theoretical basis for improvement of adolescent physical and mental health.@*Methods@#A total of 8 102 adolescents aged 12-17 years were selected by random cluster sampling method in Shanghai, Urumqi, Changsha and Kunming, using the Center for Epidemiologic Studies Depression Scale (CES-D) and the Adolescent Non Suicidal Self Injurious Behavior Assessment Questionnaire. Depressive symptoms and the occurrence of NSSI behaviors were assessed. The relationship between NSSI behaviors and depressive symptoms was analyzed using Chi square test, one way analysis and Logistic regression analysis.@*Results@#The overall detection rate of NSSI in adolescents, 24.6%, with a significantly lower detection rate in boys (23.1%) than in girls (26.2%) ( χ 2=10.97, P <0.05), and 24.7%, 24.6% in the middle school and high school segments, respectively, but the difference was not statistically significant ( χ 2=0.01, P >0.05). The overall detection rate of adolescent depressive symptoms was 49.7 % in the group with NSSI and 17.7% in the group without NSSI, with statistically significant differences ( χ 2=808.80, P < 0.01 ). The detection rates of adolescent depressive symptoms in the group with NSSI (male:44.0%, female:54.7%, middle school:49.6%, high school:49.8%) and the group without NSSI (male:14.2%, female:21.4%, middle school:14.3%, high school: 21.0 %) were statistically significant by sex and age groups ( χ 2=385.58, 412.44, 520.60, 313.78, P <0.01). Logistic regression models, after adjusting for gender and age, the risk for depressive symptoms was 2.65 times (95% CI =2.27-3.09) and 7.28 times (95% CI = 6.34- 8.37) more frequently in adolescents with episodic self injurious behavior and frequent self injurious behavior, respectively, compared to those without self injurious behavior. The association between NSSI status and depressive symptoms did not show sex differences ( P >0.05).@*Conclusion@#Adolescent NSSI behavior is positively associated with depressive symptoms, the attention should be paid to adolescent physical and mental health to reduce the occurrence of NSSI.
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Objective@#To analyze the correlation between physical activity and depressive symptoms in adolescents, so as to provide a reference for the early prevention of depression among adolescents.@*Methods@#Using a random cluster sampling method, 8 102 adolescents from Shanghai, Urumqi, Changsha and Kunming were investigated via the Physical Activity Assessment Questionnaire of Chinese Children and Adolescents aged 7 to 18 and the Center for Epidemiologic Studies Depression Scale (CES-D) for physical activity and depressive symptoms. Multivariate Logistic regression analysis was used to analyze the correlation between physical activity and depressive symptoms in adolescents.@*Results@#The proportion of adolescents who met moderate to vigorous physical activity (MVPA) standard was 37.0%, and the detection rate of depressive symptoms was 25.6%. The detection rate of depressive symptomsin compliant with MVPA standard group was significantly lower than that in non compliant group among different age and gender( χ 2=7.62-34.54, P <0.05). Adolescents with severe depressive symptoms had high light intensity physical activity(LPA) duration and low vigorous intensity physical activity(VPA) duration, while adolescents with mild depressive symptoms or asymptomatic adolescents had higher MVPA duration. There were differences in LPA and VPA among adolescents with different levels of depressive symptoms in the overall sample, and the differences were still significant among girls, middle school and statistically significant differences in LPA, moderate intensity physical activity(MPA), MVPA were also found among the high school subgroup. However, differences only in LPA were observed among boys with different levels of depression( H=46.48, 10.31, 25.02, 29.54, 30.25, 19.80, 22.20, 9.54, 8.62, 18.06, P <0.05). Multivariate Logistic regression model showed that gender and duration of MVPA were significantly related to risk of depressive symptoms( OR=1.56, 1.42, P <0.05).@*Conclusion@#Physical activity among adolescents is significantly related to depressive symptoms. MVPA may be an effective measure to reduce the degree of depressive symptoms.To improve the physical health and prevent depression among adolescents, it is important to choose appropriate physical activity types and effectively increase the duration of MVPA.
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Objective@#To understand the relationship between family environment and depressive symptoms among adolescent, and to provide a reference for adolescent mental health promotion and intervention.@*Methods@#From September to December in 2021, a questionnaire survey on family environment and depressive symptoms was conducted among 8 102 middle school students by random cluster sampling method in Shanghai, Urumqi, Changsha and Kunming. The Chi square test was used to compare the depression status of students in different family environments. Multivariate Logistic regression analysis was used to explore the relationship between family environment and depressive symptoms.@*Results@#The detection rates of possible depression, likely depression and severe depression in adolescents were 11.2%, 5.9% and 8.4%, respectively. There were significant differences in the detection rate of depression by gender, academic period, urban and rural areas, family forms and only child statu( χ 2=87.60, 27.19, 6.65, 45.59, 4.78, P <0.05). Logistic regression analysis showed that adolescents in single parent families ( OR =1.45) and reorganized families( OR =1.69) were positively correlated with the occurrence of depressive symptoms compared with those in nuclear families( P <0.01).@*Conclusion@#Compared with nuclear families, the risks of adolescent depressive symptoms in single parent families and reorganized families are higher. Attention should be paid to the mental health education of teenagers from single parents and reorganized families to ensure the development of their physical and mental health.
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Abstract@#In recent years, mental health problems such as anxiety and depression among adolescents in China have attracted attention from all walks of life. Given that adolescence is a transitional and critical period for individual development, mental health affect the developmental opportunities. Therefore, in the review, the effects of environment, psychosocial factors and behavioral patterns on depressive symptoms are analyzed by combining with the characteristics of physical and mental development among adolescents. It is found that early adolescence and even childhood should be the key period for the prevention and intervention of depression. In order to formulate effective interventions and prevention strategies, it is proposed that future research should combine real situation in China with active exploration of protective factors and early predictors of depression.
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Abstract@#In recent decades, there is a decreasing trend in physical activity, which might be associated with decline in physical and mental health among children and adolescents in China. The outbreak and spread of the COVID-19 further aggravated this trend. Under the background of normalized epidemic prevention and control, in order to deeply understand the relationship between physical activity and physical and mental health of children and adolescents, this study sorted out relevant domestic and foreign literatures, and analyzed the effects of physical activity on children and adolescents health and fitness. The positive effects of physical activity, cognition, and mental health were found to be significantly different in the type, intensity, and time of physical activity in the related health effects.
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ABSTRACT Introduction: the assessment and proper management of lower extremity soft tissue injury is very important. Because the mechanism and clinical manifestations of lower extremity soft tissue injury are varied, it is necessary to make an accurate assessment based on the specific situation of the patient. Objective: To explore the mechanism and rehabilitation methods of lower limb soft tissue sports injury. Methods: In clinical practice, external application of Chinese herbal medicine combined with cold compresses, massage, pot dipping, hot immersion irradiation and other methods were used. Results: The self-made Chinese herbal medicine external ointment, swelling and pain relieving Chinese herbal medicine wine combined with electromagnetic wave therapy instrument is one of the commonly used and effective methods to treat sports injury of lower extremity soft tissue in health care experimental centers. It has the most remarkable effect on local burning, stasis, swelling and pain caused by the soft tissue injury of various lower limbs in various parts of the human body. Conclusions: Timely functional rehabilitation training after sports injury can promote the functional healing and rehabilitation of the body after injury, maintaining the good functional state of each organ system of the body. Level of evidence II; Therapeutic studies - investigation of treatment results.
RESUMO Introdução: A avaliação e o manejo adequados de lesões do tecido mole dos membros inferiores é muito importante. Como o mecanismo e as manifestações clínicas das lesões do tecido mole dos membros inferiores são variados, é necessário fazer uma análise precisa, baseada na situação específica do paciente. Objetivo: Explorar os métodos mecânicos e de reabilitação de lesões do esporte no tecido mole de membros inferiores. Métodos: Na prática clínica, a aplicação de ervas medicinais chinesas de uso externo combinada com compressas frias, massagens, pot dipping, irradiação com imersões quentes e outros métodos foram usados. Resultados: A pomada artesanal de ervas médica de uso externo, o vinho de ervas médico chinês para o alívio de dores, combinado com a terapia de ondas eletromagnéticas é um dos métodos mais eficazes e comumente usados para tratar de lesões do esporte do tecido mole de membros inferiores em centros de saúde experimentais. Tem um efeito perceptível na queimação local, estase, inchaço e dor causados por lesões do tecido mole de vários membros inferiores em várias partes do corpo humano. Conclusões: O treinamento de reabilitação funcional adequado após lesões do esporte pode promover a recuperação e a reabilitação funcional do corpo após lesões, mantendo o estado funcional correto de cada sistema orgânico do corpo. Nível de evidência II; estudos terapêuticos - investigação de resultados de tratamento.
RESUMEN Introducción: La evaluación y manejo adecuados de lesiones del tejido blando de los miembros inferiores es muy importante. Como el mecanismo y las manifestaciones clínicas de las lesiones del tejido mole de los miembros inferiores son variados, es necesario hacer un análisis preciso, basado en la situación específica del paciente. Objetivo: Explorar los métodos mecánicos y de rehabilitación de lesiones del deporte en el tejido blando de miembros inferiores. Métodos: En la práctica clínica, se utilizaron la aplicación de hierbas medicinales chinas de uso externo combinada con compresas frías, masajes, pot dipping, irradiación con inmersiones calientes y otros métodos. Resultados: La pomada artesanal de hierbas médicas de uso externo, el vino de hierbas médico chino para alivio de dolores, combinado con la terapia de ondas electromagnéticas, es uno de los métodos más eficaces y comúnmente usados para tratar lesiones del deporte en el tejido blando de miembros inferiores en centros de salud experimentales. Tiene un efecto perceptible en el ardor local, éxtasis, hinchazón y dolor causados por lesiones del tejido blando de varios miembros inferiores en varias partes del cuerpo humano. Conclusiones: El entrenamiento de rehabilitación funcional adecuado tras lesiones del deporte puede promover la recuperación y la rehabilitación funcional del cuerpo tras lesiones, manteniendo el estado funcional correcto de cada sistema orgánico del cuerpo. Nivel de evidencia II; Estudios terapéuticos - investigación de resultados de tratamiento.
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Objective@#To explore the correlation between different nutritional status and mental sub-health of Chinese adolescents, and provide reference for improving the physical and mental health of Chinese adolescents.@*Methods@#A total of 16 545 adolescents (13-22 years old) were selected by random overall sampling method in six major administrative regions in China.The psychological part of the Multidimensional Sub-health Questionnaire of Adolescents (MSQA) was used for mental sub-health test.Chi-square test and Logistic regression analysis were used to analyze and compare the relationship between different nutritional status and mental sub-health.@*Results@#The overall detection rate of mental sub-health status in the adolescents with normal BMI group was 18.5%, while those in the lean, overweight and obese groups were 22.3%, 38.7%, and 44.7%, respectively, which were significantly different from those in the normal BMI group(χ2=478.68,P<0.05).After adjusted for gender and age, the Logistic regression model showed that compared with those with normal BMI, those who were thin (OR=1.19, 95%CI=1.09-1.30), overweight (OR=2.76, 95%CI=2.47-3.09) and obese(OR=3.43, 95%CI=2.83-4.15) had increased risk of mental sub-health.@*Conclusion@#The nutritional status of Chinese adolescents in significantly related to mental sub-heatlh,hose who are underweight, overweight and obese have significantly higher risks of mental sub-health than those who are normal.Improvement of nutritional status of adolescents is beneficial to healthy adolescent development.
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@#To investigate whether postoperative therapy can bring survival benefits to patients with locally advanced esophageal squamous cell carcinoma who have received neoadjuvant chemotherapy with TP regimen. Methods We retrospectively reviewed clinical data of 115 patients with locally advanced esophageal squamous cell carcinoma who received neoadjuvant chemotherapy with TP regimen and underwent esophagectomy in our hospital from January 2007 through December 2016. Patients were divided into two groups including a non-receiving treatment group (54 patients with 47 males and 7 females) and a receiving treatment group (61 patients with 52 males and 9 females). There were 31 patients with postoperative chemotherapy, 14 with postoperative radiotherapy, and 16 with postoperative chemotherapy and radiotherapy in the receiving treatment group. Results In the non-receiving treatment group, the 5-year median disease free survival (DFS) rate was 54.7%, and the 5-year overall survival (OS) rate was 55.3%. In the receiving treatment group, the median DFS was 46.0 months (95% CI 22.9–69.1), the 5-year DFS rate was 42.3%; and the median OS was 68.0 months (95% CI 33.0–103.0), the 5-year OS rate was 51.3%. Furthermore, there was no statistical difference between the two groups with regards to DFS (P=0.641) or OS (P=0.757) using Kaplan-Meier method. Besides, in each subgroup, the results of Cox proportional hazard model analysis showed postoperative treatment did not improve survival (P>0.05, respectively). Conclusion Postoperative treatment does not bring survival benefits to patients with esophageal squamous cell carcinoma who have received neoadjuvant chemotherapy with TP regimen.
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@#Objective To evaluate the prognosis of different node status on the basis of the eighth TNM classification for lung cancer. Methods We retrospectively reviewed the clinical data of 1 851 non-small cell lung cancer (NSCLC) patients who underwent radical resection between January 2005 and December 2014. There were 1 078 males and 773 females at age of 16–86 (59.7±9.7) years. Survival probability was estimated by the Kaplan-Meier method and significance was assessed by the log-rank test. Results This cohort study was consisted of 1 209 patients with N0, 305 with N1 and 337 with N2. N0 patients were divided into a N0a group and a N0b group according to whether the 13 and 14 level of lymph nodes were examined. The survival rate of the N0a group was significantly higher than that of the N0b group, and the 5-year survival rate was 88.9% and 81.3% (P<0.001), respectively. According to the number of lymph node metastasis stations, N1 was divided into a N1a (single) group and a N1b (multiple) group. And no significant difference was observed between the two groups in survival rate (P=0.562). Based on the presence of lymph nodes of 10–12 level, N1 was divided into a negative group and a positive group. And the negative group was found with significantly higher survival rate than the positive group (5-year survival rate of 78.4% vs. 64.3%, P=0.007). The N2 patients were divided into a single station metastasis group (a N2a1 group), a single station with N1 positive group (a N2a2 group) and a multiple station group (a N2b group), and the percentage was accounted for 22.0% (74/337), 37.7% (127/337) and 40.3% (136/337), respectively. There was a statistical difference in 5-year survival rate (62.2% vs. 56.5% vs. 37.3%) among the three groups (P=0.001). Conclusion Subgroup analysis of N staging in NSCLC patients shows significant survival differences which may be more consistent with multidisciplinary therapy under precise staging patterns.
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Non-alcoholic fatty liver disease (NAFLD) is a common disease associated with metabolic syndrome and can lead to life-threatening complications like hepatic carcinoma and cirrhosis. Exenatide, a glucagon-like peptide-1 (GLP-1) receptor agonist antidiabetic drug, has the capacity to overcome insulin resistance and attenuate hepatic steatosis but the specific underlying mechanism is unclear. This study was designed to investigate the underlying molecular mechanisms of exenatide therapy on NAFLD. We used in vivo and in vitro techniques to investigate the protective effects of exenatide on fatty liver via fat mass and obesity associated gene (FTO) in a high-fat (HF) diet-induced NAFLD animal model and related cell culture model. Exenatide significantly decreased body weight, serum glucose, insulin, insulin resistance, serum free fatty acid, triglyceride, total cholesterol, low-density lipoprotein, aspartate aminotransferase, and alanine aminotransferase levels in HF-induced obese rabbits. Histological analysis showed that exenatide significantly reversed HF-induced lipid accumulation and inflammatory changes accompanied by decreased FTO mRNA and protein expression, which were abrogated by PI3K inhibitor LY294002. This study indicated that pharmacological interventions with GLP-1 may represent a promising therapeutic strategy for NAFLD.
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Animales , Masculino , Conejos , Péptidos/farmacología , Ponzoñas/farmacología , Sustancias Protectoras/farmacología , Hígado Graso/metabolismo , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/efectos de los fármacos , Glucemia/análisis , Peso Corporal/efectos de los fármacos , Técnicas In Vitro , Regulación de la Expresión Génica/efectos de los fármacos , Morfolinas/metabolismo , Cromonas/metabolismo , Modelos Animales de Enfermedad , Ingestión de Alimentos/efectos de los fármacos , Inhibidores Enzimáticos/metabolismo , Hígado Graso/patología , Dieta Alta en Grasa , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética , Exenatida , Insulina/sangre , Malondialdehído/análisis , Obesidad/metabolismoRESUMEN
The changes of cell ultra structure as well as Ca2+ homeostasis involved in the drought-induced maize leaf senescence was investigated. Meanwhile, many indicatives of leaf senescence including thiobarbituric acid reactive substance (MDA), electrolyte leakage (EL), and chlorophyll along with soluble proteins were also detected during the process. The Polyethylene glycol6000(PEG6000)-incubated detached leaves showed a slight increase in the MDA content and electrolyte leakage during the first 30 min of our detection, which was corresponded to an unobvious alteration of the cell ultrastructure. Other typical senescence parameters measured in whole leaf exhibited a moderate elevation as well. Thereafter, however, the EL and MDA rose to a large extent, which was correlated with a dramatic damage to the cell ultrastructure with concomitant sharp decrease in the chlorophyll and soluble proteins content. The deposits of calcium antimonite, being an indicator for Ca2+ localization, were observed in the vacuoles as well as intercellular spaces in the leaves grown under normal condition. Nevertheless, after PEG treatment, it was revealed a distinct increment of Ca2+ in the cytoplasm as well as chloroplasts and nuclei. Moreover, with long-lasting treatment of PEG to the detached leaves, the concentration of Ca2+ as described above showed a continuous increment which was consist with the remarked alteration of physiological parameters and severe damage to the ultrastructure of cells, all of which indicated the leaf senescence. Such drought-induced leaf senescence might result from a loss of the cell's capability to extrude Ca2+. All above findings give us a good insight into the important role of Ca2+ homeostasis in the process of leaf senescence accelerated by the drought stress.