2005年 · 第118卷第12期

Background The urokinase plasminogen activator system is believed to play an important role in degradation of the extracellular matrix associated with cartilage and bone destruction; however its precise roles in temporomandibular disorders have not yet been clarified. The aims of this study were to investigate the gene expression of fibrinolytic factors urokinase plasminogen activator (uPA) and plasminogen activator inhibitor-1 (PAI-1) in the articular cartilage of rabbit temporomandibular joint (TMJ) with disc displacement (DD) and to probe the relationship between fibrinolytic activity and cartilage remodeling. Methods Disc displacement of right joints was performed in 36 of 78 rabbits under investigation. The animals were sacrificed at 4 days and 1, 2, 4, 8 and 12 weeks after surgery, respectively. The right joints of these animals were harvested and processed for the examination of mRNA expression of uPA and PAI-1 in articular cartilage using in situ hybridization techniques. Results The expression of uPA and PAI-1 was co-expressed weakly in the chondrocytes from transitive zone to hypertrophic zone and mineralized zone, while no hybridizing signals were shown in proliferative zone and superficial zone in control rabbits. The most striking was the up-regulation of uPA and PAI-1 mRNA in 4-day rabbits postoperatively at the onset of cartilage degeneration. The strongest hybridizing signals for uPA and PAI-1 were seen in 2-week rabbits postoperatively. After 2 weeks, the expression of uPA and PAI-1 began to decrease and reached nearly normal level at 12 weeks. Conclusions The expression of the uPA/PAI-1 system coincides with the pathological changes in condylar cartilage after DD. The uPA/PAI-1 system may be one of the essential mediators in articular cartilage remodeling.

Background Gap junction channels formed by connexin43 (Cx43) protein are important in cardiac morphogenesis, and Cx43 gene is thought to be associated with congenital heart malformation (CHM). This study was undertaken to detect the mutations of Cx43 in fetuses with CHM. Methods Cx43 extron DNA was amplified by PCR from 16 fetuses with a variety of CHM. The PCR products were analyzed by SSCP and DNA sequencing. Thirty children who had no CHM were selected as controls. Results Eight homozygous mutations of Cx43 were observed in a fetus with double outlet right ventricule (DORV), five of the 8 mutations were missense mutations including Arg239Trp, Ser251Thr, Ala253Pro, Pro283Leu and Thr290Asn, and the remaining 3 were silent polymorphisms including Gly252Gly, Pro256Pro and Thr275Thr. No mutations were found in other fetuses and the control group. Conclusions Mutations of Cx43 may be associated with congenital conotruncal anomalies. PCR-SSCP is an effective method for screening the mutations of Cx43.

Background Hemangiomas are the most common tumors in children. Some hemangiomas may require intervention because of their location, size, behavior, or potential for important complications. Pharmacological therapy with glucocorticoids is the mainstay treatment, but there is no consensus on therapeutic regimens or candidate selection, therapeutic efficacy vaires, and the mechanism mediating the beneficial effects of glucocorticoids remains unclear. This study was performed to investigate the expression patterns of the glucocorticoid receptor (GR) and its α isoform (GRα) in cutaneous hemangiomas and vascular malformations. Methods SP immunohistochemical technique was used to examine the expression of GR(e-20)(GR) and GR (p-20)(GRα) on vascular endothelial cells in 80 specimens that included 33 proliferating hemangiomas, 32 involuting hemangiomas, 7 vascular malformations as well as 8 normal skin tissues, all obtained from infants and children. GR and GRα expression in prepared tissue slides were examined using automated computer-assisted microscopic analysis. Mean gray scale values were compared among the various tumor types. Results The mean gray scale values of GR were 127.0±6.4 and 121.4±6.6 in hemangiomas and vascular malformations respectively, but this difference was not statistically significant (P=0.104). However, these values were all markedly higher than that of normal skin, which was only 108.6±6.8 (P=0.001 and P=0.000 for comparison with hemangiomas and vascular malformations respectively). The gray scale of GR in proliferation and involuting hemangiomas were 127.9±4.8 and 126.0±5.8 respectively, but this difference was not significant (P=0.146). However, GRα expression in hemangiomas, vascular malformations and normal skin declined gradually in stepwise fashion (127.3±5.4, 120.4±6.1 and 109.9±5.3 respectively; P<0.001). GRα expression was higher in proliferating hemangiomas than in involuting hemangiomas (127.2±6.3 and 122.5±6.3; P=0.004). Conclusions GR and GRα are strongly expressed in hemangiomas and vascular malformations. The expression of GRα is closely related to the phase of the hemangioma. Determination of GR and GRα may be a positive significance to understand the information of hemangiomas and vascular malformations and may further help determining proper strategies of steroid therapy for hemangiomas and vascular malformations.

Background Activation and proliferation of hepatic stellate cells (HSC) is essentially involved in the development and progression of hepatic fibrosis. The most potent growth factor for HSC is platelet-derived growth factor receptor (PDGF) and PDGF receptor β subunit (PDGFR-β) is the predominant signal transduction pathyway of PDGF which is overexpressed in activated HSC. This study investigated the cleavage activity of hammerhead ribozyme targeting PDGFR-β mRNA in HSC and the effect on biological characteristics of HSC. Methods Expression vector of anti-PDGFR-β ribozyme was constructed and transfected into rat activated HSC with lipofectamin. The positive cell clones were gained by G418 selection. The expression of PDGFR-β, α-smooth muscle actin, and type Ⅰ and type Ⅲ collagen were detected by using Northern blot, Western blot and immunocytochemical staining, respectively. The cell proliferation was determined with MTT colorimetric assay. The cell apoptosis was analyzed by using flow cytometry, acridine orange fluorescence vital staining and transmission electron microscopy. Results The expression of PDGFR-β at mRNA and protein level was markedly reduced in ribozyme-transfected HSC by 49%-57% (P<0.05-0.01). The proliferation and α-smooth muscle actin expression of ribozyme-transfected HSC were significantly decreased (P<0.05-0.01), and the type Ⅰ and type Ⅲ collagen synthesis were also reduced (P<0.01). In addition, the proliferative response of ribozyme-transfected HSC to PDGF BB was significantly inhibited. Otherwise, the apoptotic cells were significantly increased in ribozyme-transfected HSC (P<0.01), and typical apoptotic cells could be found under transmission electron microscopy. Conclusions The anti-PDGFR-β ribozyme effectively cleaved the target RNA and significantly inhibited its expression, which blocked the signal transduction of PDGF at receptor level, inhibited HSC proliferation and collagen synthesis, and induced HSC apoptosis. These|Results|suggest that inhibiting PDGFR-β expression of HSC may be a new target for the therapy of liver fibrogenesis, and ribozyme may be a useful tool for inhibiting PDGFR-β expression.

Background Although the Results of surgical treatment in cardiac valve disease continue to improve, the postoperative mortality rate and the rate of complications in patients with advanced valvular heart disease (AVHD) are still very high. We did this retrospective study to summarize the surgical experience of heart valve replacement for patients with AVHD and discuss effective ways to improve the surgical outcome. Methods From January 1994 to October 2003, surgical procedures of heart valve replacement were performed on 227 (136 men and 91 women) patients with AVHD in our Department of Cardiothoracic Surgery. The clinical data of all patients were collected and analysed. Patients’ age ranged from 10 years to 77 years. In preoperative cardiac function grading, 157 cases were NYHA III and 70 cases NYHA IV. Fifty-one patients had had cardiac operations. The ultrasonic cardiac graphs showed that 145 patients suffered from moderate or severe pulmonary hypertension and 73 had combined giant left ventricle. Mitral valve replacement was performed in 32 cases, aortic valve replacement in 90, tricuspid valve replacement in 1, combined mitral and aortic replacement in 103 and combined mitral and tricuspid replacement in 1. Nineteen patients also received surgical corrections for other minor abnormalities during the operations. A logistic model was established to evaluate the influence of perioperative factors on the mortality rate. Results The operative mortality rate was 13.2% (30/227). The main causes of death included multiple organ dysfunction syndrome (MODS), low cardiac output syndrome and ventricular fibrillation. From the|Results|of the binary noncounterpart multivariate logistic regression, the following statistically significant factors were found to influence the operative mortality rate: redo operation, age ≥55 years, preoperative NYHA cardiac function grading, extracorporeal circulation time ≥120 minutes and postoperative usage of GIK (glucose, insulin and potassium) solution. All factors were risk ones except postoperative application of GIK. The Hosmer-Lemeshow goodness of fit coefficient of this model was 0.976. Conclusions The risk factors associated with postoperative mortality rate in the patients with AVHD were redo operation, age ≥55 years, preoperative NYHA cardiac function grading and extracorporeal circulation time ≥120 minutes. Postoperative usage of GIK acted as a kind of metabolic therapy and will improve the recovery for patients with AVHD. Active perioperative management and care will play a very important role in reducing the operative risk and improving the short term outcome of surgical treatment for the patients with AVHD.

Background Due to the controversy of the oral glucose tolerance test (OGTT), diagnostic criteria for gestational diabetes mellitus (GDM) in the world and researches on GDM remain undeveloped in China. American Diabetes Association recently recommended the clinicians to diagnose GDM by OGTT Results without the third-hour glucose value. This new criteria has not been used in China. Research on the value and sensitivity of the criteria in detecting GDM is rare. The aim of our study is to analyze the characteristics of OGTT in Chinese women with GDM or gestational impaired glucose tolerance (GIGT) and to evaluate the effect of omission of the third-hour plasma glucose (PG) level in OGTT on the sensitivity of diagnosing GDM and GIGT, and the relationship between PG values of 50 g GCT or OGTT and insulin therapy. Methods A retrospective analysis was performed on medical records of 647 cases with GDM from January 1, 1989 to December 31, 2002, and 233 with GIGT. Among 647 cases of GDM, 535 cases were diagnosed by 75 g OGTT. All OGTT Results including 535 cases of GDM and 233 patients with GIGT were evaluated. Results There were 112 cases of GDM diagnosed by elevated fasting PG (FPG) without OGTT performed. Of 535 cases of GDM diagnosed by OGTT, 49.2% (263/535) women had FPG value ≥5.8 mmol/L; 90.1% (482/535) women with 1-hour PG values ≥10.6 mmol/L; 64.7% (359/535) with 2-hour PG levels ≥9.2 mmol/L. There were only 114 cases (21.3%) with abnormal 3-hour PG levels among 535 women with OGTT. Among those with abnormal 3-hour PG level, 49.1% (56/114) had abnormal glucose values in the other three points of OGTT, and 34.2% (39/114) with two other abnormal values of OGTT. Our study showed that omission of the 3-hour PG of OGTT only missed 19 cases of GDM and they would be diagnosed as GIGT. Among the 233 women with GIGT, only 4 cases had abnormal 3-hour PG. So, omission of the third-hour glucose value of OGTT only resulted in failure to diagnose 3.6% (19/535) women with GDM diagnosed by OGTT, which means 2.9% (19/647) of all the GDM and 1.7% (4/233) of GIGT in Chinese women. PG levels ≥11.2 mmol/L following 50 g GCT was highly associated with GDM necessitating insulin therapy (75.4%). An elevated FPG level was also associated with insulin therapy (59.7%). Conclusions Omission of the third-hour glucose tolerance test value still yield a higher sensitivity in diagnosing GDM and GIGT. In Chinese women, it is practicable to omit third-hour post-glucose ingestion value of the OGTT in Chinese women. PG levels ≥11.2 mmol/L following 50 g GCT mostly indicates that the requirement of insulin therapy.

Objective To review the recent development of functional MRI application in epilepsy. Data sources Both Chinese and English language literatures were researched using MEDLINE/ CD ROM (1996-2005) and the Chinese Biomedical Literature Disk (1996-2005). Study selection Published articles about functional MRI application and epilepsy were selected. Data extraction Data were mainly extracted from 38 articles which are listed in the reference section of this review. Results fMRI can be used to localize seizure foci through detecting these cerebral hemodynamic changes produced by epileptiform discharges. EEG-triggered fMRI, which has higher spatial and temporal resolution, helps to detect the spatiotemporal pattern of spike origin and propagation, and define localization of the epileptogenic focus. fMRI is also useful in language and memory cognitive function assessment and presurgical assessment of refractory epilepsy. Atypically distributed cognitive function areas can be detected by fMRI, because of cortical language and memory areas reorganization during long-term epileptic activity in patients with epilepsy. Conclusions fMRI technique plays a very important role in cognitive function and presurgical assessment of patients with epilepsy. It is meaningful for understanding pathogenesis of epilepsy.