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Purpose The aim of this study was to develop a scale to quantify the negative life events of graduate students; and to identify the associations between negative life events and emotional disorders among them. Methods Based on a literature review, qualitative interviews and direct consultation with experts in relevant fields, the study served to identify the items that could be included in the Negative Life Events Scale for graduates (LES-GS). Psychometrics was used to analyze the items for reliability and validity. A cross-sectional survey was conducted in Changsha, China to explore the association between negative life events and emotional disorders among master's and PhD students. LES-GS, Patient Health Questionnaire-9 (PHQ-9), and the Generalized Anxiety Disorder Scale-7 (GAD-7) were utilized in the survey. Results The LES-GS exhibited acceptable reliability and validity. A total of 13.24% of master's and 16.60% of PhD students experienced moderate to severe depression symptoms. Additionally, a total of 9.04% of master's students and 15.47% of PhD students experienced moderate to severe anxiety symptoms. Among the master's students, five long-term events and one short-term event life events (these included "tension with family members"; "the graduation project is not going well"; "not interested in the major"; "poor relationship with partner or spouse", "long-term financial stress", and "dispute with the mentor") were associated with an increased likelihood of emotional disorders among them. Among the PhD students, "death of a close family member" and "the publication of academic papers fails to meet the graduation requirements" were associated with an increased likelihood of emotional disorders. Conclusion The LES-GS could be used to assess life events for graduate students. The treatment of emotional problems for the master's students and the doctorial students should be designed differently.

Using microbial enzymes in transgenesis is a powerful means to introduce new functionalities in plants. Glucuronoyl esterase (GCE) is a microbial enzyme hydrolyzing the ester bond between lignin and 4-O-methyl-α-D-glucuronic acid present as a side chain of glucuronoxylan. This bond mediates lignin-carbohydrate complex (LCC) formation, considered as crucial factor of lignocellulose recalcitrance to saccharification. Previous studies showed that hybrid aspen (Populus tremula L. x tremuloides Michx.) constitutively expressing Phanerochaete carnosa Burt GCE (PcGCE) had better efficiency of cellulose-to-glucose conversion but were stunned and had lower cellulose content indicating that more studies are needed to design strategy for deployment of this enzyme in planta. Here we report that the transgenic plants exhibit premature leaf senescence, increased accumulation of calcium oxalate crystals, tyloses and necrotic lesions and have strongly activated immune defense reactions as revealed by their altered profiles of transcriptomes, metabolomes and hormones in the leaves. To elucidate if these effects are triggered by damage-associated molecular patterns (DAMPs) or by PcGCE protein perceived as a pathogen-associated molecular pattern (PAMP), we ectopically expressed in aspen an enzymatically inactive PcGCES217A. The mutated PcGCE induced similar growth retardation, leaf necrosis and premature senescence as the active one, providing evidence that PcGCE protein is recognized as PAMP. Transcriptomics analysis of young expanding leaves of 35S:PcGCE plants identified several candidates for receptors of PcGCE, which were not expressed in developing wood tissues. Grafting experiments showed that PcGCE transcripts are not cell-to-cell mobile and that PcGCE expressing leaves augment systemic responses. In agreement, expressing PcGCE in developing wood by using the wood-specific promoter (WP), avoided all off-target effects. Moreover, WP:PcGCE lines grew better than control plants providing evidence that this strategy can be used in transgenic crops dedicated for biorefinery.

This study aimed to explore the association between sleep and suicidality in the presence and absence of depressive symptoms in the rural Chinese population. The research involved a cross-sectional survey conducted in Liuyang, China, between November 2010 and August 2011. A total of 2052 participants were surveyed (987 males and 1065 females). To investigate the mediating effect of depressive symptoms in the correlation between sleep quality and suicidality. The association between sleep quality and suicidality in the absence of depressive symptoms was also explored. Suicide risk was measured using the Mini-International Neuropsychiatric Interview subscale. The visual analog scale was used to assess sleep quality. Patient Health Questionnaire-9 and Patient Health Questionnaire-2, avoiding the overlap in sleep and suicidality assessments, were used for detecting depressive symptoms in participants. Depressive symptoms partially mediated the association between sleep quality and suicidality among rural adults. Furthermore, some participants did not exhibit depressive symptoms in this study yet still exhibited a risk for suicidality, with poor sleep quality contributing significantly to their suicidality even after adjusting for cofounders. Poor sleep quality significantly increases the likelihood of suicidality in the presence and absence of depressive symptoms in the rural Chinese population. Poor sleep quality could correlate with increased suicide risk independently of depressive symptoms.

Xiao-kun Liu,1 Shan-lin Chen,1 Dan-ling Huang,1 Zi-shang Jiang,1 Yu-ting Jiang,1 Li-juan Liang,1 Lu-lu Qin2 1The First Affiliated Hospital of Hainan Medical University, Haikou, People’s Republic of China; 2Department of Social Medicine and Health Management, School of Medicine, Hunan Normal University, Changsha, People’s Republic of ChinaCorrespondence: Xiao-kun LiuThe First Affiliated Hospital of Hainan Medical University, 3 Xueyuan Road, Haikou, 571199, Hainan, People’s Republic of ChinaEmail lacyfairy@qq.comPurpose: Road safety research is important due to the large number of road traffic fatalities globally. This study investigated the influences of age, driving experience and other covariates on aggressive driving behavior.Methods: A cross-sectional survey was conducted in Yixing City, Wuxi City, Jiangsu Province, China. Regression analysis was applied to explore the influences of age and driving experience and their interactions with other covariates on aggressive driving behavior. Two analyses methodologies were used to assess the simple effect of the interactions. Firstly, the Jamovi automatic analysis classification program was used to calculate the simple slope test. Second, the SPSS macro program was also used to calculate the simple slope test also.Results: A total of 570 drivers (247 males, 282 females) participated in the survey. A negative correlation was found between age and aggressive driving behaviors, and a positive correlation was found between neuroticism and aggressive driving behaviors in the multiple regression analysis. Significant associations were also found between age, driving experience, and depression, as well as age, driving experience, and neuroticism. Simple slope tests showed that depressive symptoms could increase aggressive behaviors in the elderly and experienced drivers. When experiencing neuroticism, individuals with higher driving experience were more aggressive in driving than shorter experienced drivers.Conclusion: Age and neuroticism influenced aggressive driving behaviors. Veteran drivers could be aggressive drivers when experiencing depressive symptoms or neuroticism. Mobile intervention could be sent to the potentially risky drivers, which would be safe and broadly feasible to prevent aggressive driving behavior in the background of COVID-19.Keywords: aggressive driving behavior, age, driving experience, depressive symptoms, neuroticism

Objective: To investigate the relationship between left ventricular hypertrophy (LVH) and coronary artery disease in the very elderly (over 80 years old) patients with hypertension. Methods: One hundred twenty cases of very elderly patients with hypertension admitted to our hospital from March 2018 to December 2020 were selected and divided into two groups: the LVH group and the non-LVH group, all of whom were older aged over 80 years, including 62 patients in the LVH group and 58 patients in the non-LVH group. All patients underwent cardiac color Doppler ultrasound examination, 24-hour dynamic ECG examination, and coronary angiography or coronary CTA examination. The clinical data of the two groups were analyzed statistically. Results: There were significant differences in the number of diseased vessels, degree of coronary stenosis and vascular calcification between the two groups (P

Xiao-kun Liu,1 Shui-yuan Xiao,1,2 Liang Zhou,3 Mi Hu,2 Wei Zhou,4 Hui-ming Liu5 1Mental Health Center, Xiangya Hospital, Central South University, Changsha, Hunan, China; 2Department of Social Medicine and Health Management, Xiangya School of Public Health, Central South University, Changsha, Hunan, China; 3Affiliated Brain Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China; 4Hospital Administration Institute, Xiangya Hospital, Central South University, Changsha, Hunan, China; 5Shenzhen Kangning Hospital, Shenzhen, Guangdong, China Purpose: The aims of this study were to investigate the distribution of sleep quality and its relationship with the prevalence of pain among rural Chinese people and to explore the association between sleep quality and pain intensity among the general population in real-life settings.Methods: This cross-sectional survey included a total of 2052 adults from rural areas in Liuyang, Hunan Province, recruited through random multistage sampling. The distributions of sleep quality and pain prevalence among the participants over a 4-week period were described. Because of multicollinearity among variables, the influence of self-rated sleep quality and psychosocial covariates on pain intensity was explored using a ridge regression model.Results: The data showed that participants reporting all categories of sleep quality experienced some degree of pain. Sleep quality, along with physical and mental health, was a negative predictor of pain intensity among the general population. Symptoms of depression positively predicted pain intensity.Conclusion: Poor sleep quality increased pain intensity among the participants. Both previous research and the present data suggest that improving sleep quality may significantly decrease pain intensity in the general population. The relationship between sleep and pain may be bidirectional. This finding also suggests that treatment for sleep disorders and insomnia should be addressed in future efforts to alleviate pain intensity. Keywords: sleep, pain, depression symptoms, mental health

Purpose The aim of this study was to develop a scale to quantify the negative life events of graduate students; and to identify the associations between negative life events and emotional disorders among them. Methods Based on a literature review, qualitative interviews and direct consultation with experts in relevant fields, the study served to identify the items that could be included in the Negative Life Events Scale for graduates (LES-GS). Psychometrics was used to analyze the items for reliability and validity. A cross-sectional survey was conducted in Changsha, China to explore the association between negative life events and emotional disorders among master’s and PhD students. LES-GS, Patient Health Questionnaire-9 (PHQ-9), and the Generalized Anxiety Disorder Scale-7 (GAD-7) were utilized in the survey. Results The LES-GS exhibited acceptable reliability and validity. A total of 13.24% of master’s and 16.60% of PhD students experienced moderate to severe depression symptoms. Additionally, a total of 9.04% of master’s students and 15.47% of PhD students experienced moderate to severe anxiety symptoms. Among the master’s students, five long-term events and one short-term event life events (these included “tension with family members”; “the graduation project is not going well”; “not interested in the major”; “poor relationship with partner or spouse”, “long-term financial stress”, and “dispute with the mentor”) were associated with an increased likelihood of emotional disorders among them. Among the PhD students, “death of a close family member” and “the publication of academic papers fails to meet the graduation requirements” were associated with an increased likelihood of emotional disorders. Conclusion The LES-GS could be used to assess life events for graduate students. The treatment of emotional problems for the master’s students and the doctorial students should be designed differently.

ObjectivesTo investigate a 4-week period of pain prevalence and the risk factors of experiencing pain among a rural Chinese population sample. To explore the psychosocial and health condition predictors of pain severity and the interactions of age and gender with these factors in real-life situations among the general adult population in China.MethodsData were collected from a random multistage sample of 2052 participants (response rate=95%) in the rural areas of Liuyang, China. Visual analogue scale was used to assess participants’ pain experienced and a series of internationally validated instruments to assess their sociodemographic characteristics, self-reported health status, depression symptoms, anxiety symptoms, sleep quality, self-efficacy and perceived stress.ResultsThe pain prevalence over the 4-week period in rural China was 66.18% (62.84% for men and 68.82% for women). A logistic regression model revealed that being female (adjusted OR=1.58, 95% CI 1.24 to 2.02), age (adjusted OR=1.03, 95% CI 1.02 to 1.05), depressive symptoms (adjusted OR=1.07, 95% CI 1.02 to 1.13) and medium-quality sleep (adjusted OR=2.14, 95% CI 1.26 to 3.64) were significant risk factors for experiencing pain. General linear model analyses revealed that (1) pain severity of rural Chinese was related to self-rated physical health and social health; (2) the interactions of age, gender with employment status, depression symptoms, perceived stress and physical health were significant. Simple effect testing revealed that in different age groups, gender interacted with employment status, depression symptoms, perceived stress and physical health differently.ConclusionsImproving physical and social health could be effective in reducing the severity of pain and the treatment of pain should be designed specifically for different ages and genders among the general population.

Objective Intravascular ultrasound (IVUS) has developed as a preferable choice for optimizing the stenting procedures mainly because it will have good access to vessel size, lesion length, or severity accurately. However, it still remains unclear about the benefits of IVUS guidance in drug-eluting stent (DES) implantation for patients with unprotected left main coronary artery (ULMCA) stenosis. The aim of the present study was to evaluate the clinical outcomes with respect to IVUS-guided DES implantation for these patients. Methods A total of 336 consecutive patients from December 2010 to December 2015 were enrolled in the study. The patients were then randomly assigned into two groups: IVUS-guided group (n=167) and control group (n=169). The primary endpoint was the incidence of composite major adverse cardiac events (MACEs), including cardiac death, myocardial infarction (MI), and target vessel revascularization (TVR). The risk of stent thrombosis (ST) was chosen as the safety endpoint. Results After a 1-year follow-up, the occurrence of composite MACE in the IVUS-guided group was significantly lower than that in the control group (13.2% vs. 21.9%, p=0.031), which might mainly result from the significant reduction in the risk of cardiac death (1.8% vs. 5.9%, p=0.048). Dramatically, the risk of MI did not differ significantly between the two groups (11.4% vs. 13.6%, p=0.478), though a tended reduction in TVR was observed under IVUS guidance (4.2% vs. 8.9%, p=0.068). There was no statistical significance between the two groups with respect to the risk of target lesion revascularization (IVUS-guided vs. control: 1.2% vs. 3.0%, p=0.239) and ST (IVUS-guided vs. control: 1.2% vs. 3.0%, p=0.246). Conclusion The possible feasibility of IVUS-guided DES implantation for patients with ULMCA stenosis was supported by the present study. Larger and more powerful randomized trials were still warranted to research the whole benefits of IVUS guidance for these patients.

To establish an expert diagnosis system for cerebrovascular diseases (CVDs) and assess accuracy of the diagnosis system.An expert diagnosis system for CVDs was established and evaluated using actual clinical cases.An expert diagnosis system for CVDs was established and tested in 319 clinical patients. Diagnosis accordance was obtained in 307 patients (the diagnosis accordance rate was 96.2%). Involved were 223, 7, 23, 54 and 12 patients with cerebral thrombosis, cerebral embolism, transient ischemic attack, cerebral hemorrhage and subarachnoid hemorrhage, respectively; and diagnosis accordance was obtained in 219 (98.2%), 6 (85.7%), 23 (100%), 48 (88.9%) and 11 (91.7%), respectively.Overall, the case analysis results support and demonstrate the diagnostic reasoning accuracy of the expert diagnosis system for CVDs. With the expert diagnosis system, medical experts' diagnosis of CVDs can be effectively mimicked and auxiliary diagnosis of CVDs has been preliminarily realized, laying a foundation for increasing the diagnostic accuracy of clinical diagnoses as it pertains to CVDs.

Regulatory T cells (Tregs) and plasmacytoid dendritic cells (pDCs) play important roles in the immune escape of cancer. In this study, we investigated pDCs and pDC-induced inducible costimulator (ICOS)(+) Treg populations in peripheral blood from gastric cancer (GC) patients and healthy donors by flow cytometry. The distribution of these cells in carcinoma tissue, peritumor tissue, and normal gastric mucosa was detected by immunohistochemistry. Plasma and tissue concentration of the cytokines such as interleukin-10 and transforming growth factor-β1 were also measured. We found that the numbers of pDCs, Tregs, and ICOS(+) Tregs in peripheral blood were increased in GC patients compared with healthy donors. In tissue, Tregs and ICOS(+) Tregs were found distributing mainly in carcinoma tissue, whereas pDCs were mainly found in peritumor tissue. Moreover, the Foxp3(+) ICOS(+) /Foxp3(+) cell ratio in carcinoma and peritumor tissue were higher than that in normal tissue. There were more ICOS(+) Tregs in tumor and peritumor tissue of late-stage GC patients. There was a positive correlation between pDCs and ICOS(+) Tregs in peripheral blood and peritumor tissue from GC patients. In conclusion, pDCs may play a potential role in recruiting ICOS(+) Tregs, and both participate in the immunosuppression microenvironment of GC.

Until now, there have only been two cases describing the coexistence of angiolymphoid hyperplasia with eosinophilia (ALHE) and Kimura's disease in one patient. Herein, we report the previous case of recurrent ALHE and Kimura's disease that was successfully treated with surgery.

The secondary walls of angiosperms contain large amounts of glucuronoxylan that is thought to be covalently linked to lignin via ester bonds between 4-O-methyl-α-d-glucuronic acid (4-O-Me-GlcA) moieties in glucuronoxylan and alcohol groups in lignin. This linkage is proposed to be hydrolysed by glucuronoyl esterases (GCEs) secreted by wood-degrading fungi. We report effects of overexpression of a GCE from the white-rot basidiomycete Phanerochaete carnosa, PcGCE, in hybrid aspen (Populus tremula L. x tremuloides Michx.) on the wood composition and the saccharification efficiency.The recombinant enzyme, which was targeted to the plant cell wall using the signal peptide from hybrid aspen cellulase PttCel9B3, was constitutively expressed resulting in the appearance of GCE activity in protein extracts from developing wood.Diffuse reflectance FT-IR spectroscopy and pyrolysis–GC/MS analyses showed significant alternation in wood chemistry of transgenic plants including an increase in lignin content and S/G ratio, and a decrease in carbohydrate content. Sequential wood extractions confirmed a massive (+43%) increase of Klason lignin, which was accompanied by a ca. 5% decrease in cellulose, and ca. 20% decrease in wood extractives. Analysis of the monosaccharide composition using methanolysis showed a reduction of 4-O-Me-GlcA content without a change in Xyl contents in transgenic lines, suggesting that the covalent links between 4-O-Me-GlcA moieties and lignin protect these moieties from degradation. Enzymatic saccharification without pretreatment resulted in significant decreases of the yields of Gal, Glc, Xyl and Man in transgenic lines, consistent with their increased recalcitrance caused by the increased lignin content. In contrast, the enzymatic saccharification after acid pretreatment resulted in Glc yields similar to wild-type despite of their lower cellulose content.These data indicate that whereas PcGCE expression in hybrid aspen increases lignin deposition, the inhibitory effects of lignin are efficiently removed during acid pretreatment, and the extent of wood cellulose conversion during hydrolysis after acid pretreatment is improved in the transgenic lines possible due to reduced cell wall cross-links between cell wall biopolymers by PcGCE.

Until now, there have only been two cases describing the coexistence of angiolymphoid hyperplasia with eosinophilia (ALHE) and Kimura's disease in one patient. Herein, we report the previous case of recurrent ALHE and Kimura's disease that was successfully treated with surgery.

Background Accurate predictors of survival for patients with advanced gastric cancer treated with neoadjuvant chemotherapy are currently lacking. In this study, we aimed to evaluate the prognostic significance of the neutrophil-lymphocyte ratio (NLR) in patients with stage III-IV gastric cancer who received neoadjuvant chemotherapy. Methods We enrolled 46 patients in this study. The NLR was divided into two groups: high (>2.5) and low (≤2.5). Univariate analysis on progression-free survival (PFS) and overall survival(OS) was performed using the Kaplan-Meier and log-rank tests, and multivariate analysis was conducted using the Cox proportional hazards regression model. We analyzed whether chemotherapy normalized high NLR or not, and evaluated the prognostic significance of normalization on survival. Results The univariate analysis showed that PFS and OS were both worse for patients with high NLR than for those with low NLR before chemotherapy (median PFS 16 and 49 months, respectively, P = 0.012; median OS 21 and 52 months, P = 0.113). PFS and OS were also worse for patients with high NLR than for those with low NLR before surgery (median PFS 12 and 35 months, P = 0.019; median OS 21 and 52 months, P = 0.082). Multivariate analysis showed that both NLR before chemotherapy and surgery were independent prognostic factors of PFS. Neoadjuvant chemotherapy normalized high NLR in 11 of 24 patients, and these 11 patients had better median PFS and OS than the 13 patients who had high NLR both before chemotherapy and before surgery (PFS: 35.0 and 10.0 months, P = 0.003; OS: 60 and 16 months, P = 0.042). Conclusions NLR may serve as a potential biomarker for survival prognosis in patients with stage III-IV gastric cancer receiving neoadjuvant chemotherapy.

The relationship between angiolymphoid hyperplasia with eosinophilia (ALHE) and Kimura's disease has always been contentious. Initially, ALHE and Kimura's disease were thought to be conditions within the same disease spectrum, but it is now widely accepted that they are two separate disease entities. The two lesions may coexist in one patient. Thus, ALHE and Kimura's disease may be different manifestations of the one disease.

This study compares superovulation efficiency during different stages of the estrus cycle in mice by investigating the pudendum appearance, vaginal epithelial cell type, and the follicular development dynamics, in relation to the estrus cycle. We determined the stages of the estrus cycle by observing the pudendum and making vaginal smears of the Kunming mouse, and ascertaining the follicular development by making paraffin sections. Based on the observation, mice in stages of proestrus, oestrus, metoestrus and dioestrus were superovulated respectively, and their follicular developments and embryo collection results were tracked to ascertain the appropriate estrus cycle stage for superovulation. Our data showed that pudendum appearance and vaginal smears could effectively distinguish different stages of the estrus cycle and that ovarian tissue observation showed that follicular development, corpus luteum formation and luteolysis were regular during the estrus cycle. Likewise, during the estrus cycle of the Kunming mouse, pudendum appearance, vaginal epithelial cell type and follicular development were relational to one another. Superovulating mice in different stages of the estrus cycle showed marked differences both in pregnancy rate and average number of embryos collected. Proestrus was significantly better than metoestrus and dioestrus (P0.05), and better than oestrus, but the difference between them was not significant (P0.05). We suggest that pudendum appearance and vaginal smears can be used to distinguish estrus cycle stages and that proestrus is the optimal stage of the estrus cycle for superovulation.

SK channels are small conductance calcium-activated potassium channels that are widely expressed in different neurons with distinct subtypes. They play an important role in modulating synaptic plasticity, dopaminergic neurotransmission, and learning and memory. The present review was mainly focused on the recent findings on the contradictory roles of SK channels in modulating dopaminergic neurons in substantia nigra and in the pathogenesis of Parkinson’s disease (PD). Besides, whether modulation of SK channels could be a potential target for PD treatment was also discussed.

A TaqMan quantitative real-time PCR detection system was developed to examine transgene copy number in cotton. GhUBC1, a gene validated to be present as a single copy per haploid Gossypium hirsutum genome, was used as the endogenous reference to estimate copy number of GFP and selection marker NPTII in 28 T0 plants. This system was found to be more accurate than genomic Southern blot hybridization and could effectively tell homozygotes from heterozygotes in a T1 transgenic cotton population. Therefore it is suitable for efficient and cost effective early screening of transgenic seedlings and identifying transgene homozygotes in segregation populations.

The dynamics of dry and fresh weight, the glucose, fructose, sucrose, titratable acid contents, and activities of sucrose-metabolizing and hexose-metabolizing enzymes were examined in developing fruits of bayberry (Myrica rubra Sieb. et Zucc. cvs. 'Wuzi' and 'Biqi'). The results showed the dry and fresh weight of bayberry fruit increased with fruit development and maturation (Fig. 1), with the highest increase rate of dry matters and water occurring during later stage of fruit development (about 10 d before maturation). The change in titratable acid followed a course of "low-high-low" in developing bayberry fruits (Fig. 3). The titratable acid content reached its peak at about 18 d before fruit maturation, and then decreased rapidly. The sugar compositions in fruits of bayberry cv. 'Wuzi' were different from those in fruits of bayberry cv. 'Biqi'. The main sugar accumulated in fruits of bayberry cv. 'Wuzi' was sucrose, accounting for 2/3 of total sugars but the sucrose content in fruits of bayberry cv. 'Biqi' was below 50% of total sugars. The fructose content in fruits of bayberry cv. 'Wuzi' was 4% higher, but that in fruits of bayberry cv. 'Biqi' was 12% lower than glucose content (Fig. 2). The activities of sucrose cleavage enzymes (invertase and cleavage activity of SS) in the fruit of bayberry cv. 'Biqi' increased with fruit development and maturation, but those activities in fruit bayberry cv. 'Wuzi' were almost stable during fruit development with lower levels of enzyme activities in fruit of cv. 'Wuzi' than in cv. 'Biqi' throughout fruit development (Fig. 4 and Fig. 5A). The SPS activity increased during fruit development (Fig. 6), however, the activity peak of synthetic activity of SS occurred at the middle stage of fruit development (Fig. 5B). The FRK activity in fruit of bayberry cv. 'Wuzi' was higher than that of HXK, but the reverse was in fruit of bayberry cv. 'Biqi' (Fig. 7). These results suggested that the 2-3 weeks before fruit maturation was a key phase for the bayberry development and the formation of fruit quality. There was a correlation between water transport and dry matter accumulation. The different sucrose constitutions between two varieties may be attributed to the differences in the activity levels of the sucrose cleavage enzymes while the difference in the ratio of glucose content to fructose content may be caused by the different activity levels of the hexose-metabolizing enzymes.

To establish a stable chronic ischemic heart failure (CIHF) model of minipig caused by gradual myocardial ischemia and necrosis that was achieved with repetitive microspheres perfusion in left anterior descending artery (LAD).A total of fifteen Wuzhishan minipigs original in Hainan China (8 to 11 months old with body weight of 20 to 30 kg) were used. The 4F angiographic catheter was superselectively engaged in LAD, and 1 ml of suspending plastic microspheres fluid were given repeatedly at ten-minute intervals, which include microspheres 1.0 x 10(5)/ml, until LVEDP raising and maintaining from 15 mm Hg to 18 mm Hg and TIMI flow was less than or equal to grade 2. Electrocardiography, hemodynamic parameters, CK-MB and cTnT were monitored during the procedure. LVEF was repeatedly measured with ultracardiography at 10 d, 20 d, 30 d, 40 d, 50 d, 60 d after establishing chronic ischemic heart failure model. Meanwhile, hemodynamic indices including mRAP, mRVP, mPAP, PCWP and CO (thermo-dilution method) were measured before and two months after procedure. The success rate, stability and repetition of chronic ischemic heart failure model were identified and evaluated. Finally, myocardial infarcted area was measured and myocardial pathologic examination was investigated.Eleven minipigs survived two months after procedure. There were ten minipigs accorded with the criteria (LVEDP18 mm Hg CO reduced by 30%) of the CIHF model and the success rate was 66.7% with a mean of 3.2 +/- 0.9 times of microspheres injections and total doses of (3.2 +/- 0.9) x 10(5) microspheres. This resulted in 38.5% reduction in LVEF, 197.8% elevation in LVEDP and 46.8% declining in CO from baseline values (P0.01), while mRAP, mRVP, mPAP and PCWP increased significantly as compared with those before procedure. Cross myocardium pathology showed the ratio of necrosis area to left ventricle (LV) area was 25.4% - 34.9% (mean 28.6%) and light microscopy examination of LV myocardium revealed that intravascular semitransparent plastic microspheres distributed throughout subendocardium of left ventricular anterior and apical parts, with more numerous focal myofiber necrosis, which characterized by pathologic founding of ischemic necrosis of myocardium with fibre proliferation.A stable CIHF model could be established in Chinese Wuzhishan minipigs with intra-coronary microspheres perfusion via superselectively engaging in LAD, which was prior to those of drug-induced, tachycardia-pacing induced or coronary artery ligation-induced, and had the advantages of stability, closed chest, mild trauma higher success rate and easy for repetition. It might be suitable for using the research of CIHF as large reliable experimental animal model.