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A growing number of studies have reported that problematic social networking use (PSNU) is strongly associated with anxiety symptoms. However, due to the presence of multiple anxiety subtypes, existing research findings on the extent of this association vary widely, leading to a lack of consensus. The current meta-analysis aimed to summarize studies exploring the relationship between PSNU levels and anxiety symptoms, including generalized anxiety, social anxiety, attachment anxiety, and fear of missing out. 209 studies with a total of 172 articles were included in the meta-analysis, involving 252,337 participants from 28 countries. The results showed a moderately positive association between PSNU and generalized anxiety (GA), social anxiety (SA), attachment anxiety (AA), and fear of missing out (FoMO) respectively (GA: r = 0.388, 95% CI [0.362, 0.413]; SA: r = 0.437, 95% CI [0.395, 0.478]; AA: r = 0.345, 95% CI [0.286, 0.402]; FoMO: r = 0.496, 95% CI [0.461, 0.529]), and there were different regulatory factors between PSNU and different anxiety subtypes. This study provides the first comprehensive estimate of the association of PSNU with multiple anxiety subtypes, which vary by time of measurement, region, gender, and measurement tool.
Subject(s)
Anxiety , Social Networking , Humans , Anxiety/psychology , Internet Addiction Disorder/psychologyABSTRACT
Introduction: To evaluate whether both acute and chronic low-intensity pulsed ultrasound (LIPUS) affect brain functions of healthy male and female mice. Methods: Ultrasound (frequency: 1.5 MHz; pulse: 1.0 kHz; spatial average temporal average (SATA) intensity: 25 mW/cm2; and pulse duty cycle: 20%) was applied at mouse head in acute test for 20 minutes, and in chronic experiment for consecutive 10 days, respectively. Behaviors were then evaluated. Results: Both acute and chronic LIPUS at 25 mW/cm2 exposure did not affect the abilities of movements, mating, social interaction, and anxiety-like behaviors in the male and female mice. However, physical restraint caused struggle-like behaviors and short-time memory deficits in chronic LIPUS groups in the male mice. Conclusion: LIPUS at 25 mW/cm2 itself does not affect brain functions, while physical restraint for LIPUS therapy elicits struggle-like behaviors in the male mice. An unbound helmet targeted with ultrasound intensity at 25-50 mW/cm2 is proposed for clinical brain disease therapy.
Subject(s)
Anxiety , Long-Term Care , Female , Male , Animals , Mice , Humans , Anxiety/therapy , Heart Rate , Memory Disorders , Ultrasonic WavesABSTRACT
Theoretical models and empirical evidence suggest an association between volunteering and health outcomes in older adults. However, less is known about existing programs that involve older adults engaging in formal volunteering, especially programs for older volunteers with cognitive impairment. In this review, we summarized and evaluated different types of volunteering-based programs involving older volunteers with and without cognitive impairment. After a non-systematic literature search, we presented eight example volunteer programs. Older volunteers participate in the programs in person or remotely. In five of the programs, older volunteers without cognitive impairment participate in intergenerational engagement, support and referral, home visiting, and dementia care services. The other three programs specifically recruit older volunteers with cognitive impairment and provide intergenerational engagement and individualized volunteer activities. Both strengths and challenges identified in the programs were discussed. Different types of volunteering-based programs are available for engaging older volunteers. For volunteers to remain active during the pandemic or for volunteers who live with cognitive impairment, remote programs can be a valuable alternative. Program effects on older volunteers need to be tested in more rigorously designed studies.
Subject(s)
Cognitive Dysfunction , Volunteers , Humans , Aged , Volunteers/psychologyABSTRACT
BACKGROUND: Sleep problems and cognitive changes are typical in pregnant women with depressive symptoms. However, the relationship between sleep quality and executive dysfunction remains unclear. This study aims to explore the differences in sleep quality and cognitive inhibition between pregnant women with and without depressive symptoms in the third trimester of pregnancy and investigate the correlations between sleep quality, cognitive inhibition and depressive symptoms. METHODS: In the third trimester, 169 women without depressive symptoms and 88 women with depressive symptoms participated in the study. Edinburgh Postpartum Depression Questionnaire (EPDS) was used to assess depressive symptoms, and Pittsburgh Standard Sleep Quality Index Questionnaire (PSQI) was used to investigate sleep quality. The color-word Stroop task is used to evaluate cognitive inhibition. RESULTS: Compared with women without depressive symptoms, pregnant women with depressive symptoms showed worse sleep quality and Stroop task performances (response speed and accuracy). In addition, the speed of cognitive inhibition plays a mediating role in the relationship between sleep quality and prenatal depressive symptoms. CONCLUSION: This research emphasizes the importance of sleep quality screening and cognitive training for depression during pregnancy and childbirth in ensuring women's mental health during pregnancy and childbirth.
Subject(s)
Depression, Postpartum , Pregnant Women , Female , Pregnancy , Humans , Pregnant Women/psychology , Depression/complications , Sleep Quality , Sleep/physiology , Parturition , CognitionABSTRACT
BACKGROUND: Non-suicidal self-injury (NSSI) and suicide attempts (SAs) by adolescent patients with depression have become serious public health problems. There is still insufficient research evidence on the effects of NSSI and SAs on neurocognitive functioning in adolescents. Cognitive function alterations may be associated with SAs and self-injury. NSSI and SAs have different influencing factors. METHODS: Participants were recruited from outpatient clinics and included 142 adolescent patients with depression (12-18 years old). This cohort included the SAs group (n = 52), NSSI group (n = 65), and depression without SAs/NSSI control group (n = 25). All participants underwent a clinical interview and neuropsychological assessment for group comparisons, and post-hoc tests were performed. Finally, partial correlation analysis was used to explore factors related to changes in cognitive function. RESULTS: The SAs group performed significantly worse than the control group in executive function and working memory. The depression score was directly proportional to the executive function of the SAs group, whereas cognitive functioning in the NSSI group was associated with borderline traits and rumination. CONCLUSIONS: These findings suggest that impairment of executive function and working memory may be a common pattern in adolescent depressed patients with SAs. However, borderline traits and rumination may be indicative of NSSI but not SAs.
Subject(s)
Cognitive Dysfunction , Self-Injurious Behavior , Humans , Adolescent , Child , Cross-Sectional Studies , Depression/complications , Depression/psychology , Self-Injurious Behavior/psychology , Suicide, Attempted/psychology , Suicidal Ideation , Cognitive Dysfunction/complications , Risk FactorsABSTRACT
Introduction: One of the most common mental disorders in the perinatal period is depression, which is associated with impaired emotional functioning due to alterations in different cognitive aspects including thought and facial emotion recognition. These functional impairment may affect emerging maternal sensitivity and have lasting consequences for the dyadic relationship. The current study aimed to investigate the impact of depressive symptoms on the attention bias of infant stimuli during pregnancy. Methods: Eighty-six pregnant women completed the Edinburgh Postnatal Depression Scale and an eye-tracking task comprising infant-related emotion images. All participants showed biased attention to infant-related images. Results: First, compared to healthy pregnant women, pregnant women with depression symptoms initially directed their attention to infant-related stimuli more quickly (F (1, 84) = 6.175, p = 0.015, η2 = 0.068). Second, the two groups of pregnant women paid attention to the positive infant stimuli faster than the neutral infant stimuli, and the first fixation latency bias score was significantly smaller than that of the infant-related negative stimulus (p = 0.007). Third, compared with the neutral stimulus, the non-depression group showed a longer first gaze duration to the negative stimulus of infants (p = 0.019), while the depressive symptoms group did not show this difference. Conclusion: We speculate that structural and functional changes in affective motivation and cognitive-attention brain areas may induce these attentional bias patterns. These results provide suggestions for the implementation of clinical intervention programs to correct the attention bias of antenatal depressed women.
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BACKGROUND: This study aimed to categorize different subgroups of problematic smartphone use in Chinese college students. Differences in gender and psychosocial characteristics of the categorized groups were also examined. METHODS: A total of 1123 participants completed the Mobile Phone Addiction Index Scale, the Center for Epidemiologic Studies Depression Scale, the Perceived Social Support Scale, and the Perceived Stress Scale. Using latent profile analysis, we identified different subgroups of problematic smartphone use in college students. Multivariate logistic regression analysis was implemented to examine the relationship between latent classes and demographic and psychosocial covariates. RESULTS: The four following latent classes were identified: a low-risk group, a moderate-risk with no evasiveness group, a moderate-risk with evasiveness group, and high-risk group that accounted for 11%, 24.1%, 35.5%, and 29.4% of the total sample, respectively. Further analysis revealed that female participants were more likely to be in the moderate-risk with evasiveness and high-risk groups, and individuals with depressed mood were more likely to be in the moderate-risk and high-risk groups. CONCLUSIONS: Classifying college students according to the features of problematic smartphone use is potentially useful for understanding risk factors and developing targeted prevention and intervention programs.
Subject(s)
Smartphone , Students , Female , Humans , Asian People , Risk Factors , China/epidemiologyABSTRACT
Background: Sleep disturbance and neuropsychiatric symptoms are common clinical symptoms of cerebral small vessel disease (CSVD), but the underlying mechanism is unclear. Here, we investigated the relationship between sleep quality and neuropsychiatric performance in patients with CSVD. Methods: A total of 30 patients with CSVD and 35 healthy controls (HCs) were recruited. The 13-item Beck Depression Inventory (BDI-13), Beck Anxiety Inventory (BAI), and Symptom Check List 90 (SCL90) were used to assess depression, anxiety, and other psychological symptoms, respectively. Sleep quality was assessed using Pittsburgh Sleep Quality Index (PSQI), and cognitive function was tested using Montreal Cognitive Assessment (MoCA). Results: When compared to the HC group, the patients with CSVD showed increased anxiety and neuropsychiatric symptoms, worse sleep quality, and impaired cognition (p < 0.05). The prevalence of comorbid poor sleep quality in the patients with CSVD was approximately 46%. The patients with CSVD with poor sleep quality also had more severe neuropsychiatric symptoms. After controlling for demographic variables, sex and anxiety significantly predicted sleep quality. Conclusion: This study suggests that the prevalence of CSVD with poor sleep quality is high, and that sex and anxiety are independent risk factors for CSVD comorbid sleep quality.
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Most women in the perinatal period face sleep issues, which can affect their mental health. Only a few studies have focused on sleep trajectories and depressive symptoms of women during the perinatal period in China. This study aims to explore the development trajectory of sleep quality by classifying pregnant women according to the changes in their sleep quality during pregnancy and postpartum and investigate the correlation between different sleep quality trajectory groups and depressive symptoms. The Pittsburgh Sleep Quality Index (PSQI) was used to assess the sleep quality, and the Edinburgh Postnatal Depression Scale (EPDS) was used to assess the symptoms of depression. Participants (n = 412) completed the assessment of sleep quality, depressive symptoms, and some sociodemographic and obstetric data at 36 weeks of gestation, 1 week after delivery, and 6 weeks after delivery. The group-based trajectory model (GBTM) was used to complete the trajectory classification, and logistic regression was used to analyze the predictive factors of postpartum depressive symptoms. Four different sleep quality trajectories were determined: "stable-good," "worsening," "improving," and "stable-poor" groups. The results demonstrate that poor sleep trajectories, social support and parenting experience during the perinatal period are related to postpartum depression. Screening for prenatal sleep problems is crucial for identifying the onset of perinatal depressive symptoms.
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Background: Non-suicidal self-injury (NSSI) in adolescents is a significant mental health problem around the world. Here, we performed a meta-analysis to systematically delineate the risk factors for NSSI. Method: We searched Medline, Embase, Web of Science and Cochrane for relevant articles and abstracts published prior to 12 November 2021. Pooled odds ratios (ORs) and 95% confident intervals (CIs) were used to assess various risk factors, and publication bias was assessed by Egger's test, the trim and fill method and meta-regression. This study is registered with PROSPERO, CRD42021265885. Results: A total of 25 articles were eventually included in the analysis. Eighty risk factors were identified and classified into 7 categories: mental disorders (ORs, 1·89; 95% CI, 1·60-2·24), bullying (ORs, 1·98; 95% CI, 1·32-2·95), low health literacy (ORs, 2·20; 95% CI, 1·63-2·96), problem behaviours (ORs, 2·36; 95% CI, 2·00-2·77), adverse childhood experiences (ORs, 2·49; 95% CI, 1·85-3.34), physical symptoms (ORs, 2·85; 95% CI, 1·36-5·97) and the female gender (ORs, 2·89; 95% CI, 2·43-3·43). The range of heterogeneity (I2) was from 20·3% to 99·2%. Conclusion: This meta-analysis found that mental disorders, low health literacy, adverse childhood experiences, bullying, problem behaviours, the female gender and physical symptoms appear to be risk factors for NSSI.
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BACKGROUND: Current research on perinatal depression rarely pays attention to the continuity and volatility of depression symptoms over time, which is very important for the early prediction and prognostic evaluation of perinatal depression. This study investigated the trajectories of perinatal depression symptoms and aimed to explore the factors related to these trajectories. METHODS: The study recruited 550 women during late pregnancy (32 ± 4 weeks of gestation) and followed them up 1 and 6 weeks postpartum. Depressive symptoms were measured using the Edinburgh Postnatal Depression Scale (EPDS). Latent growth mixture modelling (LGMM) was used to identify trajectories of depressive symptoms during pregnancy. RESULTS: Two trajectories of perinatal depressive symptoms were identified: "decreasing" (n = 524, 95.3%) and "increasing" (n = 26, 4.7%). History of smoking, alcohol use and gestational hypertension increased the chance of belonging to the increasing trajectories, and a high level of social support was a protective factor for maintaining a decreasing trajectory. CONCLUSIONS: This study identified two trajectories of perinatal depression and the factors associated with each trajectory. Paying attention to these factors and providing necessary psychological support services during pregnancy would effectively reduce the incidence of perinatal depression and improve patient prognosis.
Subject(s)
Depression/epidemiology , Peripartum Period/psychology , Adult , Asian People/psychology , China/epidemiology , Female , Humans , Latent Class Analysis , Pregnancy , Protective Factors , Psychiatric Status Rating Scales , Risk FactorsABSTRACT
Background and Aims: This three-wave longitudinal study investigated the effects of stressful life events on problematic smartphone use and the mediating roles of mental health problems (i.e., depressive symptoms, poor sleep quality, and suicidal ideation) in Chinese undergraduate students. Methods: A total of 197 undergraduate students completed the three-wave surveys. Their severity of stressful life events, mental health problems, and problematic smartphone use were assessed. Results: Regression analyses revealed that stressful life events at T1 was significantly associated with problematic smartphone use at T3. Mediation analyses showed that mental health problems (i.e., depressive symptoms, poor sleep quality, and suicidal ideation) at T2 fully mediated the association between stressful life events at T1 and problematic smartphone use at T3 (B = 0.042, 0.034, and 0.022, respectively). Conclusions: The present study revealed that stressful life events and mental health problems (i.e., depressive symptoms, poor sleep quality, and suicidal ideation) are predictors of problematic smartphone use in Chinese college students.
Subject(s)
Smartphone , China/epidemiology , Humans , Longitudinal Studies , Mental Health , Students/psychologyABSTRACT
Although many risk factors for suicidal ideation have been identified, few studies have focused on suicidal ideation and pre-natal depression. The purpose was to investigate the relationship between decision-making (DM) dysfunction and sleep disturbance on suicidal ideation in pre-natal depression. Participants included 100 women in the third trimester of pregnancy, including pregnant women with pre-natal depression who had recent suicidal ideation (n = 30), pre-natal depression without SI (n = 35) and healthy controls (n = 35). The Iowa Gambling Task (IGT) was used to evaluate the DM function and the Pittsburgh Sleep Quality Index (PSQI) was used to assess the sleep index. The Edinburgh Post-natal Depression Scale (EPDS) was used to assess suicidal ideation and the seriousness of depression. Overall, the two groups with pre-natal depression showed worse sleep quality and decreased DM function compared with healthy controls. The pre-natal depression with suicidal ideation group showed a significantly higher score in subjective sleep quality and a lower score in block 5 of IGT than the pre-natal depression without suicidal ideation group. Further correlation analysis showed that suicidal ideation positively correlated with subjective sleep quality, sleep duration, and daytime function, and negatively correlated with IGT scores. Sleep disturbance and impaired DM function may be risk factors for suicidal ideation in pre-natal depression.
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BACKGROUND: The undergraduate program of psychiatry has been widely established in recent years to improve the education and recruitment of psychiatrists in China. We aim to investigate the career choice of medical students majoring in psychiatry in China and the influential factors. METHOD: This multicenter study was conducted in 26 medical schools in China from May to October of 2019. Participants included 4610 medical students majoring in psychiatry and 3857 medical students majoring in clinical medicine. Multivariable logistic regression was used to investigate the influential factors of students' choices of psychiatry at matriculation and as a career. RESULTS: 44.08% of psychiatry majored students gave psychiatry as a first choice at matriculation, and 56.67% of them would choose psychiatry as a career, which was in sharp contrast to the proportion of clinical medicine majored students who would choose psychiatry as a career (0.69%). Personal interest (59.61%), suggestions from family members (27.96%), and experiencing mental problems (23.19%) were main reasons for choosing psychiatry major at matriculation. Personal interest (odds ratio [OR] = 2.12, 95% confidence interval [CI] = 1.87-2.40), experiencing a psychiatry clerkship (OR = 1.99, 95% CI = 1.28-3.08), being female (OR = 1.50, 95% CI = 1.30-1.68), experiencing mental problems (OR = 1.33, 95% CI = 1.28-1.56), and suggestions from family members (OR = 1.25, 95% CI = 1.08-1.46) correlated positively with students' choice of psychiatry as career. Students who lacked psychiatry knowledge (OR = 0.49, 95% CI = 0.29-0.85) or chose psychiatry because of lower admission scores (OR = 0.80, 95% CI = 0.63-0.97) were less likely to choose psychiatry as a career. CONCLUSION: More than half of psychiatry majored medical school students planned to choose psychiatry as their career, whereas very few students in the clinic medicine major would make this choice. Increasing students' interest in psychiatry, strengthening psychiatry clerkships, and popularizing psychiatric knowledge are modifiable factors to increase the psychiatry career intention. The extent to which medical students' attitudes toward psychiatry can be changed through medical school education and greater exposure to psychiatry will need further investigation.
Subject(s)
Psychiatry , Students, Medical , Career Choice , China , Female , Humans , Psychiatry/education , Schools, Medical , Surveys and QuestionnairesABSTRACT
Cognitive and sensory deficits were considered a core feature of major depressive disorder (MDD). However, few studies investigated stereopsis integrity in patients with MDD. Thus, the objectives of this study investigated stereopsis integrity and its correlations with cognitive function and depressive symptom in patients with MDD. 90 patients with MDD and 116 healthy controls (HCs) were enrolled in this study. Their stereoacuity was evaluated using the Titmus Stereopsis Test as well as assessing their cognitive function and depressive symptom by the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and Hamilton Depression Scale (HAMD). Log seconds of arc was significantly higher in patients than HCs (1.92 ± 0.41 versus 1.67 ± 0.16, t = 5.35, p < 0.0001). The percentage of patients with correct stereopsis detection was markedly declined in 400 (z = 3.06, p = 0.002), 200 (z = 3.84, p < 0.001), 140 (z = 4.73, p < 0.001), 100 (z = 4.58, p < 0.001), 80 (z = 5.06, p < 0.001), 60 (z = 4.72, p < 0.001), 50 (z = 4.24, p < 0.001), and 40 (z = 4.85, p < 0.001) seconds of arc compared with HCs. Log seconds of arc was significantly correlated with the RBANS total score (r = -0.38, p < 0.0001), subscores of attention (r = -0.49, p < 0.0001) and language (r = -0.33, p = 0.001) rather than HAMD score (r = 0.03, p = 0.78) in MDD patients. In addition, log seconds of arc was significantly related to the RBANS total score (r = -0.58, p < 0.0001) and language score (r = -0.45, p = 0.006) rather than attention score (r = -0.30, p = 0.07) in HCs. Further stepwise multivariate regression analyses showed the negative correlation of log seconds of arc with attention score (ß = -0.80, t = -3.95, p < 0.0001) rather than HAMD score (ß = -0.008, t = -0.09, p = 0.93) in MDD patients. However, there was no relationship between log seconds of arc and attention score in HCs (ß = 1.52, t = 1.19, p = 0.24). Our results identified the marked deficits of stereopsis in MDD patients that were tightly correlated with their attention functioning rather than depressive symptom.
Subject(s)
Attention/physiology , Cognition , Depressive Disorder, Major/physiopathology , Depth Perception/physiology , Perceptual Disorders , Adult , Brief Psychiatric Rating Scale , Depressive Disorder, Major/complications , Female , Humans , Male , Models, Statistical , Neuropsychological Tests/statistics & numerical dataABSTRACT
OBJECTIVE: Postpartum depression (PPD) has received increasing attention due to its harmful impacts and high incidence. PPD is affected by physiological and psychological factors, but the conclusions are not uniform at present, so this study explored the risk factors of postpartum depressive symptoms (PPDS) in Chinese population. METHODS: A total of 397 women attending the obstetric department of the First Affiliated Hospital of Wenzhou Medical University participated in the questionnaire survey, mainly through a cross sectional study. At 6 weeks postpartum, the Edinburgh Postpartum Depression Scale (EPDS) and Pittsburgh Sleep Quality Index (PSQI) were used to assess PPDS and sleep quality, respectively. RESULTS: The incidence of probable PPDS in our study population was 14.6% at 6 weeks postpartum. Women with blood group A had an almost 3-fold greater risk of PPDS than those with blood group B (OR [95% CI], 2.99 [1.43-6.28], p = 0.004). After adjusting for potential confounding variables, the blood group A phenotype was significantly more prevalent in women with PPDS compared to blood group B (OR [95% CI], 2.65 [1.23-5.70], p = 0.01). CONCLUSIONS: Compared to women with blood groups B, AB or O, women with blood group A had high odds of PPDS. If this result can be demonstrated and replicated in other populations, blood group A may be a useful predictor of risk for PPDS in Chinese postpartum women.
Subject(s)
Depression, Postpartum/psychology , Adult , Asian People , China , Cross-Sectional Studies , Female , Humans , Pregnancy , Psychiatric Status Rating Scales , Risk Factors , Surveys and Questionnaires , Time FactorsABSTRACT
Background: During an epidemic, both frontline and non-frontline medical staff endure stressful work circumstances that render their mental health a major public health concern. This study aims at investigating and comparing the prevalence and severity of mental health symptoms (i.e., anxiety, depression and insomnia) between frontline medical staff and non-frontline medical staff during the coronavirus disease 2019 (COVID-19) outbreak. It also seeks to evaluate the association of their mental health with occupational stress. Methods: A cross-sectional study was conducted in Wenzhou, China from 2020 February 16th to 2020 March 2th. A total of 524 medical staff responded to the Generalized Anxiety Disorder Scale, the Patient Health Questionnaire, the Insomnia Severity Index, the Occupational stress Questionnaire, and a demographic data form. Data were principally analyzed with logistic regression. Results: Of the 524 participants, 31.3% reported depression, 41.2% reported anxiety, and 39.3% reported insomnia. Compared with the citizens during the COVID-19 epidemic, medical staff experienced higher level of anxiety, depression and insomnia, especially the frontline medical staff. Furthermore, male, married medical staff with poorer physical health reported lower mental health. Frontline medical staff endorsed higher self-reported occupational stress, especially higher occupational hazards, than non-frontline medical staff. In addition, four indicators on occupational stress (working intensity, working time, working difficulty and working risk) were correlated positively with mental health symptoms. Regression analyses found a significant association between occupational stress and mental health symptoms in both frontline and non-frontline medical staff during COVID-19 outbreak. Conclusion: The results indicated that during the COVID-19 epidemic, medical staff experienced higher levels of anxiety, depression and insomnia than citizens, and their occupational stress had positive effects on their psychological distress. These findings emphasize the importance of occupational stress management interventions to decrease the risk of developing mental health problems among the medical staff during a biological disaster.
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The aim of the present study was to investigate whether metallothionein was involved in the protection of lung ischemic preconditioning (IP) against lung ischemia-reperfusion (I/R) injury. Adult male Sprague-Dawley rats were randomly divided into 3 groups based upon the intervention (n=8): control group (C), lung I/R group (I/R), lung I/R+IP group (IP). At the end of the experiment, the content of metallothionein was tested in lung tissue. Blood specimens collected from the arteria carotis were tested for the contents of malondialdehyde (MDA), the activities of superoxide dismutase (SOD) and myeloperoxidase (MPO). The pneumocyte apoptosis index (AI) was determined by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL). Ultrastructural changes of lung tissue were observed by using transmission electron microscope. The results showed that in I/R group, the content of metallothionein was decreased (P<0.05), the content of MDA and MPO activity were increased (P<0.01), and SOD activity was decreased (P<0.01), compared with those in control group. IP treatment significantly increased the content of metallothionein (P<0.01), attenuated the MDA level (P<0.05) and MPO activity (P<0.01), and improved SOD activity (P<0.01) in blood serum. The number of TUNEL-positive cells in IP group was significantly reduced compared with that in I/R group (P<0.01). There were abnormal ultrastructural changes in I/R group, which were markedly reversed in IP group. In conclusion, IP may protect lung against I/R injury by inducing the expression of metallothionein.