Volume 120  ·   Issue 03  ·  2007

Abstract：Background Overgrazing was assumed to increase the population density of small mammals that are the intermediate hosts of Echinococcus multilocularis, the pathogen of alveolar echinococcosis in the Qinghai Tibet Plateau. This research tested the hypothesis that overgrazing might promote Echinococcus multilocularis transmission through increasing populations of small mammal, intermediate hosts in Tibetan pastoral communities.Methods Grazing practices, small mammal indices and dog Echinococcus rnultilocularis infection data were collected to analyze the relation between overgrazing and Echinococcus rnultilocularis transmission using nonpararnetric tests and multiple stepwise logistic regression.Results In the investigated area, raising livestock was a key industry. The communal pastures existed and the available forage was deficient for grazing. Open (common) pastures were overgrazed and had higher burrow density of small mammals compared with neighboring fenced (private) pastures; this high overgrazing pressure on the open pastures measured by neighboring fenced area led to higher burrow density of small mammals in open pastures. The median burrow density of small mammals in open pastures was independently associated with nearby canine Echinococcus multilocularis infection (P=0.003, OR=1.048).Conclusion Overgrazing may promote the transmission of Echinococcus multilocularis through increasing the population density of small mammals。

Abstract：Background The peritoneum response to peritoneal dialysis can lead to fibrosis. The transforming growth factor β1(TGF-β1) plays a key role in regulating tissue repair and remodelling after injury. Connective tissue growth factor (CTGF),a downstream mediator of TGF-β1 inducing fibrosis, has been implicated in peritoneal fibrosis. Vascular endothelial growth factor (VEGF) plays a key role in angiogenesis that can hasten peritoneal fibrosis. In this study, we investigated the effect of small interfering RNA (siRNA) of CTGF by pRETRO-SUPER (PRS) retrovirus vector on the expression of CTGF and VEGF in human peritoneal mesothelial cells.Methods Retrovirus producing CTGF siRNA were constructed from the inverted oligonucleotides and transferred into packaging cell line PT67 with lipofectamine, and the virus supernatant was used to infect human peritoneal mesothelial cell (HPMC). The cells were divided into seven groups: low glucose DMEM, low glucose DMEM + TGF-β1 5 ng/ml, low glucose DMEM + TGF-β1 5 ng/ml + PRS-CTGF-siRNA1-4 and low glucose DMEM + TGF-β1 5 ng/ml + PRS. The expression of CTGF and VEGF were measured by semiquantitative RT-PCR and Western blot.Results Low levels of CTGF and VEGF were detected in confluent HPMCs. Following stimulation with TGF-β1, the levels of CTGF and VEGF were significantly upregulated (P＜0.01). Introduction of PRS-CTGF-siRNA1-4 resulted in the significant reduction of CTGF mRNA and protein, and VEGF mRNA (P＜0.01), especially in groups PRS-CTGF-siRNA1 and PRS-CTGF-siRNA4. The introduction of PRS void vector did not have these effects (P＞0.05).Conclusions The expression of CTGF siRNA mediated by PRS retrovirus vector can effectively reduce the level of CTGF and VEGF induced by TGF-β1 in cultured HPMCs. This study may provide potential therapeutic strategies to prevent the peritoneal fibrosis。

Abstract：Background Percutaneous microballoon compression (PMC) for trigeminal neuralgia is an important therapeutic method. The aim of this study was to review the effects of PMC for trigeminal neuralgia in 276 patients.Methods From December 2000 to May 2003, 276 patients with trigeminal neuralgia were treated with PMC. The course of the disease ranged from 3 months to 38 years. Under the guidance of C-arm X-ray, 14# needle was placed into the foramen ovale using the classical Hakanson's technique. Fogarty balloon catheter was navigated into the Meckel's cave tenderly. A small amount of Omnipaque was slowly injected to inflate the balloon and compress the trigeminal ganglion for 3 to10 minutes.Results A total of 290 PMC were performed on the 276 patients. Among them, 252 had immediate relief from pain. The patients were followed up for a mean of 18.7 months (range, 4 to 32), 14 of them had a recurrence. Of the 14 patients, 12 were re-operated with PMC, and the pain was all controlled successfully.Conclusions PMC is an effective and technically simple method for trigeminal neuralgia. For older patients with trigeminal neuralgia, it may be the first choice。

Abstract：Background Olfactory neuroblastoma (ONB) is a rare tumor that often arise from the nasal cavity. The aim of this study was to investigate the clinical characteristics and treatments of intracranial invasive ONB.Methods Between July 2001 and August 2005, 5 patients with intracranial invasive ONB were treated in our department. Their clinical features, radiological and pathological characteristics, and surgical treatments were analyzed.Among the 5 patients, 1 received transnasal biopsy, and 4 were operated through the transfrontal or extended bifrontal approaches to reconstruct the skull base. After the operation, all the patients received radiotherapy, and one received chemotherapy. They were followed up for 6 to 45 months.Results The ONB was resected totally in the 4 patients. In all the patients, nasal obstruction was alleviated without cerebrospinal fluid leakage. The visual acuity was improved in 3 patients, who had a decreased visual acuity before the operation. Two patients had metastasis into the lumbosacral spinal canal 6 and 8 months after the operation, one of them received a second operation and the other died.Concluslon ONB has no specific symptoms. Intracranial ONB should be resected as far as possible, and treated by radiotherapy afterthe operation。

Abstract：Background About 50%-70% of patients with Chiari malformation I (CMI) presented with syringomyelia (SM), which is supposed to be related to abnormal cerebrospinal fluid (CSF) flow around the foramen magnum. The aim of this study was to investigate the cerebrospinal fluid dynamics at levels of the aqueduct and upper cervical spine in patients with CMI associated with SM, and to discuss the possible mechanism of formation of SM.Methods From January to April 2004, we examined 10 adult patients with symptomatic CMI associated with SM and 10 healthy volunteers by phase-contrast MRI. CSF flow patterns were evaluated at seven regions of interest (ROI): the aqueduct and ventral and dorsal subarachnoid spaces of the spine at levels of the cerebellar tonsil, C2-3, and C5-6. The CSF flow waveforms were analyzed by measuring CSF circulation time, durations and maximum velocities of cranial- and caudal-directed flows, and the ratio between the two maximum velocities. Data were analyzed by ttest using SPSS 11.5.Results We found no definite communication between the fourth ventricle and syringomyelia by MRI in the 10 patients.In both the groups, we observed cranial-directed flow of CSF in the early cardiac systolic phase, which changed the direction from cranial to caudal from the middle systolic phase to the early diastolic phase, and then turned back in cranial direction in the late diastolic phase. The CSF flow disappeared at the dorsal ROI at the level of C2-3 in 3 patients and 1 volunteer, and at the level of C5-6 in 6 patients and 3 volunteers. The durations of CSF circulation at all the ROIs were significantly shorter in the patients than those in the healthy volunteers (P=0.014 at the midbrain aqueduct, P=0.019 at the inferior margin of the cerebellar tonsil, P=0.014 at the level of C2-3, and P=0.022 at the level of C5-6). No significant difference existed between the two groups in the initial point and duration of the caudal-directed CSF flow during a cardiac cycle at all the ROIs. The maximum velocities of both cranial- and caudal-directed CSF flows were significantly higher in the patients than those in the volunteers at the aqueduct (P=0.018 and P=0.007) and ventral ROI at the inferior margin of the cerebellar tonsil (P＜0.001 and P=0.002), as so did the maximum velocities of the caudal-directed flow in the ventral and dorsal ROIs at the level of C2-3 (P=0.004; P=0.007).Conclusions The direction of CSF flow changes in accordance with cardiac cycle. The syringomyelia in patients with CMI may be due to the decreased circulation time and abnormal dynamics of the CSF in the upper cervical segment. The decompression of the foramen magnum with dural plasty is an alternative for patients with CMI associated with SM。

Abstract：Background Lower cervical dislocation with locked facets is common in cervical injury. The locked facets include unilateral and bilateral types. Different successful closed reduction rates has been achieved between unilateral and bilateral types by using rapid skull traction, which was commonly used to reduce the cervical dislocation. It is important to investigate a suitable management specific to patients with different types of cervical locked facets.Methods A total of 38 patients with cervical dislocation with locked facet due to cervical injury treated by rapid skull traction and operation from 1988 to 2005 were reviewed. Rapid skull traction was used in all the patients. Successful closed reduction rate was 88.0% in patients with bilateral cervical locked facets and that was 15.4% in those with unilateral cervical locked facets. These data were then statistically compared by Chi-square test. Patients who were reduced successfully underwent anterior cervical discectomy and fusion at the injured level, and those who failed in closed reduction received posterior open reduction and fixation.Results In this series, there was statistically significant difference (P＜0.05) in the rate of successful closed skull traction reduction between unilateral and bilateral locked facets dislocation. Unilateral cervical locked facets dislocation was not easily reduced by skull traction which was suitable for reduction of bilateral cervical locked facets dislocation. However,unilateral cervical locked facets dislocation can be reduced by posterior open reduction.Conclusions Unilateral cervical locked facets dislocation should be treated immediately with posterior open reduction and instrumentation. Bilateral cervical locked facets dislocation can be reduced by rapid skull traction firstly and anterior cervical discectomy and interbody fusion later。

Abstract：Background Discoid lateral meniscus of the knee is common in Chinese population. There has been considerable debate about the best treatment for discoid lateral meniscus tears. The purpose of this study was to observe the effect of arthroscopic meniscectomy for the treatment of discoid lateral meniscus tears.Methods Between July 1999 and December 2004, arthroscopic meniscectomy was performed on 62 menisci of 57 patients with discoid lateral meniscus tears (52 unilateral, 5 bilateral). 41 menisci were "complete discoid meniscus", 21 "incomplete". According to the extent of the meniscus tears, partial meniscectomy was performed on 52 knees, total meniscectomy on 7 knees, and partial meniscectomy combined with meniscus suture on 3 knees through an arthroscope.After the operations, early rehabilitation training programs, including straight-leg-raising and range-of-motion exercises,were carried out. 51 patients were followed up for 1 year 2 months to 6 years 5 months (mean, 3 years 3 months), 6 patients were lost. Lysholm-Ⅱ scoring system was used to assess the function of the knee joints before the operation and during the follow-up.Results The operations on all the 62 knees were successful without complications. The patients could walk normally after completing the 2-week postoperation rehabilitation program. After 3-4 weeks they could lead a normal life and participate in a moderate amount of sports or other physical activities. The mean Lysholm-Ⅱ score was 89 (60-100)during the follow-up, which was significantly higher than that before the operation (50, range 34-74; P＜0.01). 88% of the patients achieved excellent or good clinical results.Conclusions Arthroscopic meniscectomy is an alternative for treatment of discoid lateral meniscus tears with minimal traumatic effects. It can achieve early mobilization and a low complication rate, as well as the preservation of the meniscus structure and functions to the largest extent. In combination with proper rehabilitation training, the operation can lead to good or excellent results。

Abstract：Background lcariine is a flavonoid isolated from a traditional Chinese medicine Epimedium pubescens and is the main active compound of it. Recently, Epimedium pubescens was found to have a therapeutic effect on osteoporosis. But the mechanism is unclear. The aim of the study was to research the effect of lcariine on the proliferation and differentiation of human osteoblasts.Methods Human osteoblasts were obtained byinducing human marrow mesenchymal stem cells (hMSCs) directionally and were cultured in the presence of various concentrations of lcariine. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test was used to observe the effect of lcariine on cell proliferation. The activity of alkaline phosphatase (ALP) and the amount of calcified nodules were assayed to observe the effect on cell differentiation.The expression of bone morphogenetic protein 2 (BMP-2) mRNA was detected by reverse transcriptase-polymerase chain reaction (RT-PCR).Results Icariine (20 μg/ml) increased significantly the proliferation of human osteoblasts. And, lcariine (10 μg/ml and 20μg/ml) increased the activity of ALP and the amount of calcified nodules of human osteoblasts significantly (P＜0.05).BMP-2 mRNA synthesis was elevated significantly in response to lcariine (20 μg/ml).Conclusions lcariine has a direct stimulatory effect on the proliferation and differentiation of cultured human osteoblastcells in vitro, which may be mediated by increasing production of BMP-2 in osteoblasts。

Abstract：Background Myocardial protection during off-pump coronary artery bypass grafting (OPCABG) is a multifactorial problem in which maintaining stable systemic hemodynamics is very important. In this study passive graft perfusion (PGP) was applied to investigate the effect during and after OPCABG as evaluated by cardiac troponin I (CTnl) and hemodynamic indexes.Methods Thirty first-time patients underwent OPCABG under one surgeon. They were randomly divided into two groups: The passive graft perfusion group (PGP, n=15) received distal coronary perfusion during the anastomosis and immediate graft perfusion after the distal anastomosis. The control group, no graft perfusion group, (NGP, n=15)received no graft perfusion after the distal anastomosis. The results of the two protocols were evaluated by concentration of CTnl and hemodynamic indexes before induction and after operation.Results There were no statistically significant differences between these two groups in their perioperation parameters.The level of CTnl increased postoperatively, reached its peak at 6 hours (P＜0.05) and recovered by the 6 days postoperative. Compared with the control group the concentration of CTnl in the PGP group was significantly lower at 6 and 24 hours (P＜0.01). Compared with the NGP group, cardiac index (Cl) in the PGP group was higher at 12 and 24 hours after operation (P＜0.05). The period of mechanical ventilation was significantly shorter in the PGP group than in the NGP group (P＜0.05).Conclusion PGP can increase the flow to the myocardium and shorten the heart ischemia time, thus maintain stable systemic hemodynamics, supply a satisfactory Cl after surgery and improve surgery outcome。

Abstract：Background Adrenomedullin is a potent vasodilating peptide and involved in many cardiovascular diseases. However,whether adrenomedullin is involved in the pathogenesis of diabetic cardiomyopathy is still unknown. Our aim was to characterize the expression pattern of adrenomedullin in the myocardium of streptozotocin-induced diabetic rats.Methods The weight, blood glucose, and urine glucose of 20 streptozotocin-induced diabetic rats were measured before and after model induction in the diabetic and control groups. The alteration of the adrenomedullin expression was explored in the left ventricular myocardium in both groups by immunohistochemistry. Changes in heart ultrastructure were also analyzed by using hemotoxylin and eosin staining and transmission electron microscopy. All data were analyzed by the independent samples ttest.Results The data of weight, blood glucose, and urine glucose had no significant difference between the control and the diabetic groups before animal model induction. Four weeks after the induction of diabetes, the differences between the two groups in weight, blood glucose, and urine glucose were distinct. When compared with the control group, the diabetic group showed ultrastructural changes including hypertrophy, fibrosis, myofibrillar disarrangements, mitochonddal disruption, and increase in nuclear membrane invaginations. A significant decrease of adrenomedullin expression was also observed in cardiac myocytes of the diabetic rats (P＜0.01).Conclusions Our study provides experimental evidence that hyperglycemia could damage cardiac myocytes.Down-regulation of cardioprotective peptide adrenomedullin in the myocardium of streptozotocin-induced diabetic rats may contribute to the diabetic cardiomyopathy and left ventricular dysfunction。

Abstract：Background Natural articular cartilage has a limited capacity for spontaneous regeneration. Controlled release of transforming growth factor-β1 (TGF-β1) to cartilage defects can enhance chondrogenesis. In this study, we assessed the feasibility of using biodegradable chitosan microspheres as carriers for controlled TGF-β1 delivery and the effect of released TGF-β1 on the chondrogenic potential of chondrocytes.Methods Chitosan scaffolds and chitosan microspheres loaded with TGF-β1 were prepared by the freeze-drying and the emulsion-crosslinking method respectively. In vitro drug release kinetics, as measured by enzyme-linked immunosorbent assay, was monitored for 7 days. Lysozyme degradation was performed for 4 weeks to detect in vitro degradability of the scaffolds and the microspheres. Rabbit chondrocytes were seeded on the scaffolds containing TGF-β1 microspheres and incubated in vitro for 3 weeks. Histological examination and type Ⅱ collagen immunohistochemical staining was performed to evaluate the effects of released TGF-β1 on cell adhesivity, proliferation and synthesis of the extracellular matrix.Results TGF-β1 was encapsulated into chitosan microspheres and the encapsulation efficiency of TGF-β1 was high (90.1%). During 4 weeks of incubation in lysozyme solution for in vitro degradation, the mass of both the scaffolds and the microspheres decreased continuously and significant morphological changes was noticed. From the release experiments, it was found that TGF-β1 could be released from the microspheres in a multiphasic fashion including an initial burst phase, a slow linear release phase and a plateau phase. The release amount of TGF-β1 was 37.4%, 50.7%,61.3%, and 63.5% for 1, 3, 5, and 7 days respectively. At 21 days after cultivation, type Ⅱ collagen immunohistochemical staining was performed. The mean percentage of positive cells for collagen type Ⅱ in control group (32.7%± 10.4%) was significantly lower than that in the controlled TGF-β1 release group (92.4%±4.8%, P＜0.05). Both the proliferation rate and production of collagen type Ⅱ in the transforming growth factor-β1 microsphere incorporated scaffolds were significantly higher than those in the scaffolds without microspheres, indicating that the activity of TGF-β1 was retained during microsphere fabrication and after growth factor release.Conclusion Chitosan microspheres can serve as delivery vehicles for controlled release of TGF-β1, and the released growth factor can augment chondrocytes proliferation and synthesis of extracellular matrix. Chitosan scaffolds incorporated with chitosan microspheres loaded with TGF-β1 possess a promising potential to be applied for controlled cytokine delivery and cartilage tissue engineering。

Chronic kidney disease (CKD) is a significant interactive disease in patients with diabetes,hypertension, and cardiovascular disease with major morbidity and mortality consequences and high costs to the healthcare system.1 CKD is characterized by a gradual loss of renal function。

Thoracolumbar burst fracture, a common condition in clinic, often leads to severe spinal instability and neurologic deficit. In most cases, the compression that caused by backward protrusion of the fracture fragments to the spinal cord, makes complete decompression difficult through a posterior approach. Here, we reviewed the clinical records of 22 patients with thoracolumbar burst fracture treated by anterior corpectomy,decompression of the spinal cord, and implantation of titanium mesh cage。

Heparin therapy for preeclampsia has been reported frequently.1-3 Most of the authors used heparin to prevent thrombosis and achieved good results. But its mechanism is not clear.4 Here we describe a case of severe early-onset preeclampsia complicated with hypercoagulable state, fetal growth restriction, and twin-twin transfusion syndrome, that responded well to heparin。

Congenital short pancreas, also known as partial agenesis or hypoplasia of the dorsal pancreas1 is a rare congenital abnormality consisting of the parenchyma and ductal system restricted to the head with some residual dorsal tapering and arborizing ducts communicating with the minor papill.2 Complete pancreatic agenesis is fatal, and only nine possible examples of partial agenesis have been previously reported in adults in the literature.3-10 Three of them were polysplenia syndrome associated with short pancreas,and only six patients with congenital short pancreas with normal situs. Here we present a new case associated with steatorrhoea。

Solitary luteinized follicle cyst, a rare cause of ovarian enlargement during pregnancy and puerperium, is a self-limited disease that can regress spontaneously after labor. The complications of the disease include ovarian torsion, intracystic hemorrhage, and rupture; endocrine disturbances have not been reported.1-4 Here we report a case of solitary luteinized follicle cyst of pregnancy,which required surgical intervention owing to persistent postpartum vaginal bleeding。

Liver transplantation (LT) has become a common method for end-stage liver disease. Although the incidence of biliary complications after LT has decreased to 8% to 20% in recent years,1,2 it is still one of the main factors affecting the life quality and long-term survival of recipients.3,4 As an uncommon complication, the mucocele formation of cystic duct remnant may compress or obstruct the common hepatic duct and result in injury to the liver graft。

Although the surgical treatment for hilar cholangiocarcinoma represents the only potentially curative option, local excision and major hepatectomy1 have failed to produce a favorable survival figure over the last decade. This is partly due to local tumor recurrences within the resection margin, perineural sheaths infiltration,and the regional lymph nodes metastasis after the surgery.Recently, an extended bile duct resection combined with total hepatectomy, pancreatoduodenectomy, and

Although situs inversus with dextrocardia is a rare clinical phenomenon, the association with coronary artery disease(CAD) is at the same frequency as in the general population.1,2 Few cases of dextrocardia complicated with CAD was reported before. The feasibility and prognosis of percutaneous coronary intervention (PCI) in such case still remains unclear because of the uncommon anatomical abnormality,especially in the drug-eluting stent (DES) era. Here we report a female case with dextrocardia and CAD was successfully treated by DES implantation。