Effect of Patellar Morphology on the Risk of Osteochondral Fracture after Patellar Dislocation: A Cross-sectional Study.

OBJECTIVE: The risk of osteochondral fracture (OCF) after patellar dislocation has been shown to be related to patellofemoral anatomy, but its relationship to patellar morphology remains unknown. The aim of this study was to investigate the associations between patellar morphology and the risk of OCF after patellar dislocation. METHODS: A total of 140 patients with patellar dislocation between January 2018 and June 2023 were enrolled in this study and divided into two groups. Sixty-five patellar dislocation patients with OCF were included in the OCF group, while 75 patellar dislocation patients without OCF were included in the non-OCF group. Computed tomography was used to compare measurements of patellar morphology including Wiberg classification, patellar width and thickness, Wiberg angle, Wiberg index, facet ratio, lateral patellar facet angle, and patellar tilt angle. A logistic regression model was performed to evaluate the correlations between patellar morphology and the risk of OCF after patellar dislocation. Receiver operating characteristic curves were used to calculate the area under the curve (AUC) and determine the diagnostic values of patellar morphology for OCF after patellar dislocation. Subgroup analyses for gender and age were conducted to compare the differences in patellar morphology of PD patients. RESULTS: Wiberg angle was significantly lower in the OCF group (p = 0.017), while Wiberg index (p = 0.002) and facet ratio (p = 0.023) were significantly higher in the OCF group. According to the results of logistic regression analysis, Wiberg angle (odds ratio [OR] = 0.96, p = 0.022) and Wiberg index (OR = 1.105, p = 0.032) were the final relevant factors for the occurrence of OCF after patellar dislocation. The AUC was 0.622 (95% confidence interval [CI]: 0.529-0.714) for Wiberg angle, 0.65 (95% CI: 0.558-0.742) for Wiberg index, and 0.702 (95% CI: 0.615-0.788) for the combination of Wiberg angle plus Wiberg index. CONCLUSION: Wiberg angle and Wiberg index were independent risk factors for the occurrence of osteochondral fracture after patellar dislocation. Moreover, Wiberg angle, Wiberg index, and the combination of Wiberg angle plus Wiberg index had good predictive diagnostic value for the occurrence of OCF after patellar dislocation.

Circadian clock gene BMAL1 regulates STAR expression in goose ovarian preovulatory granulosa cells.

The ovarian circadian clock plays a regulatory role in the avian ovulation-oviposition cycle. However, little is known regarding the ovarian circadian clock of geese. In this study, we investigated rhythmic changes in clock genes over a 48-h period and identified potential clock-controlled genes involved in progesterone synthesis in goose ovarian preovulatory granulosa cells. The results showed that BMAL1, CRY1, and CRY2, as well as 4 genes (LHR, STAR, CYP11A1, and HSD3B) involved in progesterone synthesis exhibited rhythmic expression patterns in goose ovarian preovulatory granulosa cells over a 48-h period. Knockdown of BMAL1 decreased the progesterone concentration and downregulated STAR mRNA and protein levels in goose ovarian preovulatory granulosa cells. Overexpression of BMAL1 increased the progesterone concentration and upregulated the STAR mRNA level in goose ovarian preovulatory granulosa cells. Moreover, we demonstrated that the BMAL1/CLOCK complex activated the transcription of goose STAR gene by binding to an E-box motif. These results suggest that the circadian clock is involved in the regulation of progesterone synthesis in goose ovarian preovulatory granulosa cells by orchestrating the transcription of steroidogenesis-related genes.

Effect of Heat Stress on Egg Production, Steroid Hormone Synthesis, and Related Gene Expression in Chicken Preovulatory Follicular Granulosa Cells.

This study was conducted to elucidate the molecular mechanisms underlying heat stress (HS)-induced abnormal egg-laying in laying hens. Hy-Line brown laying hens were exposed to HS at 32 °C or maintained at 22 °C (control) for 14 days. In addition, granulosa cells (GCs) from preovulatory follicles were subjected to normal (37 °C) or high (41 °C or 43 °C) temperatures in vitro. Proliferation, apoptosis, and steroidogenesis were investigated, and the expression of estrogen and progesterone synthesis-related genes was detected. The results confirmed that laying hens reared under HS had impaired laying performance. HS inhibited proliferation, increased apoptosis, and altered the GC ultrastructure. HS also elevated progesterone secretion by increasing the expression of steroidogenic acute regulatory protein (StAR), cytochrome P450 family 11 subfamily A member 1 (CYP11A1), and 3b-hydroxysteroid dehydrogenase (3ß-HSD). In addition, HS inhibited estrogen synthesis in GCs by decreasing the expression of the follicle-stimulating hormone receptor (FSHR) and cytochrome P450 family 19 subfamily A member 1 (CYP19A1). The upregulation of heat shock 70 kDa protein (HSP70) under HS was also observed. Collectively, laying hens exposed to high temperatures experienced damage to follicular GCs and steroidogenesis dysfunction, which reduced their laying performance. This study provides a molecular mechanism for the abnormal laying performance of hens subjected to HS.

Two new sesquiterpenes from Sonchus oleraceus and inhibitory mechanism on murine haemangioendothelioma (EOMA) cell lines.

Sonchus oleraceus is a kind of medicinal and edible plant which is widely distributed. In this study, two new sesquiterpenes 1 and 2 along with three known compounds 3-5 were isolated from Sonchus oleraceus by the methods of column chromatography. The structures of the two novel compounds were constructed on the basis of HR-MS and NMR spectra. Cytotoxicities of 1 and 2 were assayed on EOMA cell lines and 1 exhibited no inhibitory effect while 2 elicited moderate inhibitory effect on EOMA cells with IC50 value of 26.5 µM. Western Blot assay indicated that 2 could suppress EOMA cell proliferation by inducing apoptosis through Bax/caspase-3 pathway.

[Application of pie-crusting technique of deep medial collateral ligament under arthroscopy in repairing posterior horn of medial meniscus tears].

OBJECTIVE: To explore effectiveness and safety of an inside-out, arthroscopic deep medial collateral ligament pie-crusting release in treating posterior horn of medial meniscus (PHMM) tear in tight medial tibiofemoral compartment of knee joint. METHODS: From January 2016 to December 2017, 61 patients (61 knees) were underwent arthroscopic partial meniscectomies for PHMM tear in tight medial tibiofemoral compartment of knee joint, who were divided into valgus group and pie-crusting group according to exposure of PHMM region . There were 28 patients in valgus group, including 12 males and 16 females aged from 27 to 60 years old with an average age of (35.75±7.57) years old;who were performed conventional valgused knee to exporsure PHMM region. There were 33 patients in pie-crusting group, including 15 males and 18 females aged from 26 to 58 years old with an average age of (36.06±7.93) years old;who were treated with inside-out, arthroscopic deep MCL pie crusting release technique with MM-Ⅱ meniscus suture package (Smith & Nephew). Operation time, preoperative and postopertaive Lysholm score of knee joint, injury of MCL between two groups were recorded and compared. RESULTS: All patients were followed up from 12 to 18 months with an average of (15.19±2.22) months. The incisions were healed at stageⅠ. There were no statistical difference in anatomical classification of PHMM between two groups(P>0.05). There was difference in opertaion time between valgus group (83.32±5.01) min and pie-crusting group (50.06±3.67) min (P<0.05). Postopertaive Lysholm score of knee joint at 3 months in two groups were higher than that of before operation (P<0.05), and Lysholm total score of knee joint in pie-crusting group was higher than that of valgus group (P<0.05). Acocording to Lysholm score of knee joint, 7 patients got excellent results, 12 good, 7 moderate and 2 poor in valgus group;19 patients got excellent results, 10 good, 4 moderate in pie-crusting group;and had difference between two groups (P<0.05). MCL injury of valgus group (15 patients with degree 0, 10 patients with degreeⅠ, 3 patients with degreeⅡ, 0 patient with degree Ⅲ) was higher than pie-crusting group(28 patients with degree 0, 5 patients with degreeⅠ, 0 patient with degreeⅡ, 0 patient with degreeⅢ)(P<0.05), while there was no differnce between two groups in MCL injury at 1 month after opertaion (P>0.05) . CONCLUSION: The inside-out, arthroscopic deep MCL pie-crusting release for the treatment of posterior horn of medial meniscus tear in tight medial tibiofemoral could expand working apace, shorten operation time, reduce injury to MCL and obtain good clinical efficacy.

[Ressarch of prior-localization femoral tunnel in medial patellofemoral ligament reconstruction].

OBJECTIVE: To introduce the method of prior-localization femoral tunnel by using a special positioning tool under the C-arm radiographic machine before surgery, and to study the effect on the knee function recovery after medial patellofemoral ligament (MPFL) reconstruction. METHODS: Between January 2014 and January 2016, 32 patients with recurrent unilateral knee patellar dislocation were treated by arthroscopic patellofemoral lateral retinaculum release and MPFL reconstruction. The femoral tunnel position during MPFL reconstruction was prior-localizated under C-arm radiographic machine before operation. There were 8 males and 24 females, aged from 15 to 37 years, with an average of 23.8 years. The time from injury to admission ranged from 1 to 24 months, with an average of 9.7 months. Isometric point distance was measured on CT three-dimensional reconstruction image after operation to evaluate whether the position of femoral tunnel was isometric, and knee joint function was evaluated by Lysholm score. Spearman correlation analysis was performed between isometric point distance and Lysholm score. RESULTS: All the 32 patients were followed up 12-18 months (mean, 14.2 months). No symptoms of patellar subluxation or dislocation was found during follow-up. Patellar extrapolation test and patellar extrapolation fear test were negative. The isometric point distance was 1.5-5.9 mm (mean, 3.44 mm) at 3 days after operation. All femoral tunnels were located in equidistant tunnels. At last follow-up, the Lysholm score of the patients was 92.8±2.1, which was significantly improved when compared with preoperative score (54.4±2.8) ( t=61.911, P=0.000). Isometric point distance was negatively correlated with Lysholm score ( r=-0.454, P=0.009). CONCLUSION: C-arm radiographic machine can locate the femoral tunnel position of MPFL easily and accurately before operation. The short-term and medium-term effectiveness are satisfactory, and the ionizing radiation injury caused by multiple fluoroscopy during operation is avoided.

Associations between circulating IgG antibodies to Apolipoprotein B100-derived peptide antigens and acute coronary syndrome in a Chinese Han population.

Objectives: Acute coronary syndrome (ACS) is the major cause of mortality worldwide and caused mainly by atherosclerosis of coronary arteries. Apolipoprotein B100 (ApoB100) is a major component of low-density lipoprotein (LDL) and its oxidation can trigger inflammation in vascular endothelial cells leading to atherosclerosis. The association between antibodies to ApoB100-derived antigens and atherosclerotic diseases has been studied in recent years, but the findings appear to be controversial. The present study developed an ELISA in-house with ApoB100-derived peptide antigens to circulating anti-ApoB100 IgG antibodies in patients with ACS. Methods: Fifteen ApoB100-derived peptide antigens (Ag1-Ag15) were designed to develop an in-house ELISA for the detection of circulating anti-ApoB100 IgG levels in 350 patients with ACS and 201 control subjects amongst a Chinese population. Binary logistic regression was applied to examine the differences in anti-ApoB IgG levels between the patient group and the control group with adjustment for a number of confounding factors; the correlation between anti-ApoB100 IgG levels and clinical characteristics was also tested. Results: Patients with ACS had significantly higher levels of plasma IgG for Ag1 (adjusted P<0.001) and Ag10 antigens (adjusted P<0.001). There was no significant increase in the levels of IgG to the other 13 antigens in these ACS patients. In the control group, anti-Ag10 IgG levels were positively correlated with age, high-density lipoprotein (HDL), and ApoA levels (P≤0.001 for all) and negatively correlated with blood triglyceride (TG) (P=0.008); in the patient group, anti-Ag10 IgG levels were positively correlated with LDL (P=0.003), and negatively correlated with ApoA (P=0.048) and systolic blood pressure (SBP) (P=0.036). The area under ROC (receiver operator characteristic) curve (AUC) was 0.612 (95% confidence interval (CI): 0.560-0.664; P<0.001) in anti-Ag1 IgG assay and 0.621 (95% CI: 0.569-0.672; P<0.001) in anti-Ag10 IgG assay. Conclusion: Circulating IgG for ApoB100-derived peptide antigens may be a useful biomarker of ACS, although anti-ApoB IgG levels were not associated with the coronary artery plaque burden characterized by the coronary Gensini score.

A brief review: the therapeutic potential of bone marrow mesenchymal stem cells in myocardial infarction.

Myocardial infarction (MI) results in dysfunction and irreversible loss of cardiomyocytes and is among the most serious health threats today. Bone marrow mesenchymal stem cells (BMSCs), with their capacity for multidirectional differentiation, low immunogenicity, and high portability, can serve as ideal seed cells in cardiovascular disease therapy. In this review, we examine recent literature concerning the application of BMSCs for the treatment of MI and consider the following aspects: activity of transplanted cells, migration and homing of BMSCs, immunomodulatory and anti-inflammatory effects of BMSCs, anti-fibrotic activity of BMSCs, the role of BMSCs in angiogenesis, and differentiation of BMSCs into cardiomyocyte-like cells and endothelial cells. Each aspect is complementary to the others and together they promote the repair of cardiomyocytes by BMSCs after MI. Although transplantation of BMSCs has enabled new options for MI treatment, the critical issue we must now address is the reduced viability of transplanted BMSCs due to inadequate blood supply, poor nourishment of cells, and generation of free radicals. More clinical trials are needed to prove the therapeutic potential of BMSCs in MI.

Induction of out-of-season egg laying by artificial photoperiod in Yangzhou geese and the associated endocrine and molecular regulation mechanisms.

This study was carried out to induce out-of-season breeding, in the summer, and to achieve high reproductive performance using artificial photoperiod manipulation in the long-day breeding Yangzhou goose. Young geese were subject to a two-phase short-to-long (group A) or a three-phase (long-short-long; group B) photoperiod program February through October. Egg-laying was induced to start similarly in both groups in May, increased to a peak level in July, and then decreased gradually through to October. The peak and post-peak laying rates were higher with the three-phase than with the two-phase program. Plasma progesterone concentrations changed similarly in the two groups, increasing from low levels during the pre-lay periods until the peak laying stage, then decreasing with decline in the egg-laying rate. Plasma T3 concentrations increased from the beginning of the experiment to form the first peak under a short photoperiod, declined to a trough at peak lay and then progressively increased to high levels towards the end of the experiment. Plasma T4 concentrations increased throughout the experiment, showing little response to changes in photoperiod. GnIH mRNA expression level in the hypothalamus steadily decreased from high levels under the short photoperiod to a nadir at peak of lay, but was abruptly up-regulated by over a thousand-fold thereafter. This mRNA expression pattern was also shared by GnIHR, VIPR, TRHR, TSH, and PRL genes in the pituitary gland, and to lesser extent, by GnRH, VIP, and TRH genes in the hypothalamus. Pituitary GnRHR mRNA expression levels changed in a similar manner to that of reproductive activities of geese in both groups. FSH beta subunits mRNA expression levels increased to high levels after day 11 of the long photoperiod, and were higher in group B than in group A at peak laying. LH beta gene expression level was similarly upregulated by photoperiod and was higher in group B than in group A when used the multivariable and two-way analyses of variance. Taken together, photoperiod, through regulation of expression of an array of genes in the hypothalamus and pituitary gland, synchronized stimulation and refractoriness of the reproductive system in Yangzhou geese. The higher out-of-season egg laying performance following the three-phase photo-program treatment was mediated by higher FSH beta and LH beta subunit mRNA expression levels.

Transcriptome sequencing analysis of porcine granulosa cells treated with an anti-inhibin antibody.

Inhibin can regulate granulosa cell proliferation and function via direct action on granulosa cells, or indirectly through stimulation of pituitary follicle-stimulating hormone secretion. Thus far, it has not been possible to unravel or formulate the chain of molecular events that lead to enhanced granulosa cell proliferation and function using conventional gene expression analysis. The aim of this study was to examine the biological effects of immuno-neutralization of inhibin bioactivity in porcine granulosa cells using transcriptome profiling by the RNA-seq technology. Treatment of granulosa cells with anti-inhibin α subunit antibodies increased both cell proliferation and estradiol secretion. Data revealed by RNA sequencing were subjected to bioinformatic analysis. The results showed that a total of 476 genes, including 27 novel genes, were differentially expressed in anti- inhibin antibody-treated granulosa cells compared to untreated granulosa cells. RNA sequencing data were validated by qRT-PCR which confirmed differential expression (upregulation and downregulation) of eighteen of twenty selected genes A total of 476 differentially expressed genes were enriched in processes such as matrix remodeling, chemokine activity, protein binding, and structural molecular activities, and which could be related to granulosa cell proliferation, estradiol synthesis, and ovarian follicle growth. In particular, the data emphasized the importance of extracellular matrix remodeling and the involvement of chemokines in enhanced granulosa cell function, which are important features of ovarian follicle growth, development, maturation, and ovulation. This study provided a new level of understanding of enhanced granulosa cell function and ovarian follicle development achieved through immuno-neutralization of endogenous inhibin bioactivity.

Production of biologically active recombinant goose FSH in a single chain form with a CTP linker sequence.

FSH is a glycoprotein hormone secreted by the pituitary gland that is essential for gonadal development and reproductive function. In avian reproduction study, especially in avian reproduction hormone study, it is hindered by the lack of biologically active FSH. In order to overcome this shortcoming, we prepared recombinant goose FSH as a single chain molecule and tested its biological activities in the present study. Coding sequences for mature peptides of goose FSH α and ß subunits were amplified from goose pituitary cDNA. A chimeric gene containing α and ß subunit sequences linked by the hCG carboxyl terminal peptide coding sequence was constructed. The recombinant gene was inserted into the pcDNA3.1-Fc eukaryotic expression vector to form pcDNA-Fc-gFSHß-CTP-α and then transfected into 293-F cells. A recombinant, single chain goose FSH was expressed and verified by SDS-PAGE and western blot analysis, and was purified using Protein A agarose affinity and gel filtration chromatography. Biological activity analysis results showed that the recombinant, chimeric goose FSH possesses the function of stimulating estradiol secretion and cell proliferation, in cultured chicken granulosa cells. These results indicated that bioactive, recombinant goose FSH has been successfully prepared in vitro. The recombinant goose FSH will have the potential of being used as a research tool for studying avian reproductive activities, and as a standard for developing avian FSH bioassays.

Detection of circulating IgG antibodies to apolipoprotein B100 in acute myocardial infarction.

A number of studies have reported an association between increased levels of antibodies against oxidized low-density lipoprotein (oxLDL) and cardiovascular disease, but the anti-oxLDL antibody has not been confirmed to serve as an effective biomarker for prediction of acute myocardial infarction (AMI). Apolipoprotein B100 (ApoB100)-derived peptide fragments generated by proteolytic degradation and aldehyde modification are the major antigens in oxLDL, and so the present work was undertaken to detect circulating IgG for Apo-B100-derived peptide antigens. An in-house enzyme-linked immunosorbent assay (ELISA) was developed with eight ApoB100-derived peptide antigens (Ag1-Ag8) to detect circulating anti-ApoB100 IgG levels in 267 patients with AMI and 201 control subjects. Binary logistic regression analysis revealed that circulating IgG for Ag1 was significantly higher in the patient group than the control group (P < 0.001) after adjustment for age, gender, smoking, hypertension, diabetes and circulating levels of cholesterol, HDL, LDL, ApoA and ApoB100. None of the other seven antigens detected an increase in IgG levels in AMI patients compared with control subjects. Spearman correlation analysis showed no correlation between IgG antibody for Ag1 and clinical characteristics. In conclusion, the linear peptide antigens derived from ApoB100 may be suitable for the development of an ELISA antibody test for prediction of AMI, although further confirmation is still needed in large-scale clinical studies.

Apolipoprotein A5 and apolipoprotein C3 single nucleotide polymorphisms are correlated with an increased risk of coronary heart disease: a case-control and meta-analysis study.

BACKGROUND: Triglycerides (TGs) are proatherogenic lipoproteins involving the risk of coronary heart disease (CHD), while apolipoprotein A5 (APOA5) and apolipoprotein C3 (APOC3) are main lipoproteins composing TG-rich lipoproteins. In this study, we aim to explore the correlation of CHD with APOA5 -1131 T > C and APOC3 -455 T > C single nucleotide polymorphisms (SNPs). METHODS: A sum of 210 CHD patients, hospitalized between Jan. 2013 and Mar. 2015 at China-Japan Union Hospital, Jilin University, were selected as our case group and 223 healthy individuals who had physical examination at same hospital at the same period were selected as control group. The frequency distribution of genotypes of APOA5 -1131 T > C and APOC3 -455 T > C SNPs were measured by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The Stata 12.0 software was utilized for statistical analyses. RESULTS: There was no significant difference on age and sex between case and control group (P > 0.05). History of smoking, drinking, hypertension and diabetes mellitus, body mass index and levels of TG and fasting blood sugar in case group were shown to be higher than control group (P < 0.05), while levels of total cholesterol, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol in case group were lower than control group (P < 0.05). Both CC and TC' + CC frequencies of APOA5 -1131 T > C and APOC3 -455 T > C in case group were higher compared to control group (both P < 0.05). Additionally, T allele frequencies of the two SNPs in case group were lower than control group, while C allele in case group has higher frequencies compared to control group (both P < 0.05). The results of meta-analysis under allele and dominant models showed that APOA5 -1131 T > C and APOC3 -455 T > C SNPs are likely to increase the risk of CHD (both P < 0.05). CONCLUSION: APOA5 -1131 T > C and APOC3 -455 T > C SNPs may play potent roles in the development and progression of CHD.

The characteristics of oviposition and hormonal and gene regulation of ovarian follicle development in Magang geese.

BACKGROUND: Egg laying in Magang geese is characterized by extended interruption between clutches and lowing laying rate. Both the ovarian follicular development and ovulation characteristics, and the associated endocrine and molecular regulatory mechanisms involved are poorly understood, but could be important for guiding development of molecule aided selection of egg laying performances in geese. This study, therefore, recorded egg-laying characteristics of Magang geese, and the endocrine and molecular regulatory mechanisms of ovarian follicular development, maturation, and ovulation in Magang geese. METHODS: Oviposition, ovarian follicle development, and reproductive hormone and gene expression profiles were observed in a small flock of Magang geese. RESULTS: Greater than 73% of eggs were laid during the day. The average oviposition interval was 46.8 h (36-55 h). It took approximately 18 days for large white follicles to develop into mature F1 follicles; follicular growth was exponential. LHR expression levels increased from the small to the large mature follicles, but FSHR expression decreased in the granulosa and thecal layers. As the follicles matured, inhibin alpha and inhibin betaA expression increased in the granulosa layer. Activin IR, activin IIRA, activin IIRB, and beta-glycan expressions also increased as the follicles increased in size, but were more abundantly expressed in the thecal than in the granulosa layers. During the oviposition cycle, plasma concentrations of gonadal hormones decreased rapidly, whereas the level of PGFM peaked around ovulation. The profiles of activin, inhibin, follistatin, estradiol, and progesterone leading to ovulation were characterized. CONCLUSIONS: The molecular and endocrine mechanisms that regulate follicular development in Magang geese are similar to those in chickens. Moreover, gonadotropin regulation and interaction between activin, inhibin, and follistatin secretion may govern 3-stage maturation in the final preovulatory follicles in Magang geese. The rapid rebound of post-ovulatory secretions of inhibin and follistatin may inhibit recruitment of new SYF recruitment once a sequence of eggs is started, and may limit the egg clutch size to no more than the number of LYFs present before the first sequence egg.

MiR-17-5p impairs trafficking of H-ERG K+ channel protein by targeting multiple er stress-related chaperones during chronic oxidative stress.

BACKGROUND: To investigate if microRNAs (miRNAs) play a role in regulating h-ERG trafficking in the setting of chronic oxidative stress as a common deleterious factor for many cardiac disorders. METHODS: We treated neonatal rat ventricular myocytes and HEK293 cells with stable expression of h-ERG with H2O2 for 12 h and 48 h. Expression of miR-17-5p seed miRNAs was quantified by real-time RT-PCR. Protein levels of chaperones and h-ERG trafficking were measured by Western blot analysis. Luciferase reporter gene assay was used to study miRNA and target interactions. Whole-cell patch-clamp techniques were employed to record h-ERG K(+) current. RESULTS: H-ERG trafficking was impaired by H2O2 after 48 h treatment, accompanied by reciprocal changes of expression between miR-17-5p seed miRNAs and several chaperones (Hsp70, Hsc70, CANX, and Golga2), with the former upregulated and the latter downregulated. We established these chaperones as targets for miR-17-5p. Application miR-17-5p inhibitor rescued H2O2-induced impairment of h-ERG trafficking. Upregulation of endogenous by H2O2 or forced miR-17-5p expression either reduced h-ERG current. Sequestration of AP1 by its decoy molecule eliminated the upregulation of miR-17-5p, and ameliorated impairment of h-ERG trafficking. CONCLUSIONS: Collectively, deregulation of the miR-17-5p seed family miRNAs can cause severe impairment of h-ERG trafficking through targeting multiple ER stress-related chaperones, and activation of AP1 likely accounts for the deleterious upregulation of these miRNAs, in the setting of prolonged duration of oxidative stress. These findings revealed the role of miRNAs in h-ERG trafficking, which may contribute to the cardiac electrical disturbances associated with oxidative stress.

[Screen and identification of the relative protein expressed in the acute tractive spinal cord injury in rats].

OBJECTIVE: To screen and identify the relative protein expressed in the acute tractive spinal cord injury (TSCI) in rats. METHODS: Ten adult Sprague Dawley rats were randomly divided into Sham group and TSCI group, 5 rats in each group. Rats from Sham group and TSCI group at 1 day after surgery were sacrificed for harvesting T13-L2 spinal tissue specimens. The extraction and quantitation of protein in the spinal tissue was finished firstly. Proteins from spinal tissue were separated by two-dimensional electrophoresis (2-DE) and identified by mass spectrometry (MS). The different expression map was established in each group, and proteins express differently was determined by comparing the level of each spot with gel imaging software and manually. Proteins were identified by High performance liquid chromatography-electrospray tandem (NanoUPLC-ESI-MS/MS) and peptide sequence tag with tandem MS combining with database respectively. After that, the function of these identified proteins was known and classified. RESULTS: There were 22 differential protein expression spots were found between Sham group and TSCI group. Among them, 18 spots were up-regulated and 4 were down-regulated. 4 differential protein expression spots were newly found in TSCI group. Sixteen significant proteins were identified by NanoUPLC-ESI-MS/MS. Four kind of proteins were related to apoptosis, 3 in nerve signal transduction and 6 in metabolism, respectively. Unnamed proteins were 3. CONCLUSIONS: The differential expression proteins were found between Sham group and TSCI group. These identified proteins may play important role in the process of injury and recovery through transduction nerve signal, regulating nerve cells apoptosis and metabolism.

[Establishment of tractive spinal cord injury model in rats with a novel spinal distractor].

OBJECTIVE: To develop a tractive spinal cord injury model in rats with a novel spinal distractor so as to supply the reliable animal model for researching the pathological mechanism and rehabilitation treatment of tractive spinal cord injury. METHODS: A novel spinal distractor was prepared based on previous study. Sixty adult Sprague Dawley rats (weighing 250-300 g) were randomly divided into 5 groups, 12 rats in each group. T12-L3 spinal structures in the rear area were exposed and then T13-L2 spinal cords were revealed via dual laminectomy and kept integrity. In group A, a novel spinal distractor was placed without distraction; in groups B, C, D, and E, the T12-L3 spines were traced with a novel spinal distractor which put on transverse process of T12-L3 vertebrae. During the tractive period, the somatosensory evoked potential (SEP) was used to monitor spinal cord function. The SEP amplitudes descended 50% and kept distracting for 5 minutes in group B and for 10 minutes in group C, and descended 70% and kept distracting for 5 minutes in group D and for 10 minutes in group E, respectively to establish the tractive spinal cord injury model of T11-L2. The improved combine behavioral score (ICBS) was recorded at 1 and 7 days after injury in 6 rats of each group. The T13-L2 spinal tissue specimens were harvested for the morphological observation by HE and Nissl's staining and for neurons counting. RESULTS: In group A, the ICBS score was 0 at 1 and 7 days after operation, showing significant difference when compared with the scores of the other groups (P < 0.05). The ICBS scores of groups D and E were significantly higher than those of groups B and C (P < 0.05). Edema and hemorrhage were observed in spinal cord surface and normal morphological structures were destroyed at different extent in groups B, C, D, and E at 1 day. There were adherence and congestion between spinal cord surface and peripheral issue without luster at 7 days, and dura depression was observed at the injury section, especially in group E. Necrosis and dissolution occurred in some neurons, and Nissl body structure dissolved or disappeared in groups B, C, D, and E. The neuron counting gradually decreased in accordance with the aggravation of injury in groups B, C, D, and E, showing significant difference when compared with group A (P < 0.05). Significant differences in neuron counting were found among groups B, C, D, and E (P < 0.05). CONCLUSION: The tractive spinal cord injury model in rats can be successfully established with novel spinal distractor, and the model established by SEP amplitude descending 70% and keeping distracting for 10 minutes is more suitable for study in tractive spinal cord injury.

[Expert tibial nails in treatment of complex tibial fractures of type C].

OBJECTIVE: To study the clinical effect of expert tibial nail (ETN) in the treatment of the complex tibial fractures of type C. METHODS: From May to October 2008, 10 cases of complex tibial fractures of type C were treated with unreamed ETN and closed reduction. There were 7 males and 3 females aging from 23 to 50 years with an average age of 39 years. Fracture was caused by traffic accident in 6 cases, by crush in 2 cases, and by falling from height in 2 cases. According to Association for the Study of Internal Fixation (AO/ASIF) classification, there were 2 cases of 42-C1 fractures, 4 cases of 42-C2 fractures, and 4 cases of 42-C3 fractures; including 4 cases of closed fractures and 6 cases of open fractures (2 cases of Gustilo type I and 4 cases of Gustilo type II). RESULTS: The mean duration of surgery and blood loss were 75 minutes (range, 60-110 minutes) and 55 mL (range, 20-100 mL), respectively. All the incision healed by first intension without complication of infection. All cases were followed up for 12-17 months (average 14 months). X-ray films showed that no breakage of nail, iatrogenic fracture, limb shortening, and angulation deformity occurred. All fractures healed after 3-8 months (average 4.2 months). At last follow-up according to Johner-Wruhs standard for the functional recovery, the results were excellent in 8 cases and good in 2 cases. CONCLUSION: ETN has an angular stable locking system for intramedullary nails, which can enhance axial and transverse stability for the treatment of complex tibial fractures of type C. It will provide firm fixation and minimal invasion.