Volume 86  ·   Issue 15  ·  2006

China is a country where the incidence of oxacillin-resistant Staphylococcus aureus (MRSA) strains is very high, while the incidence of vancomycin-resistant Enterococcus (VRE) strains is very low. Vancomycin and teicoplanin maintain high activity against MRSA and VRE, and there are no reports of vancomycin-resistant Staphylococcus aureus (Staphylococcus aureus) isolates in China. However, it is necessary to understand the epidemic dynamics of VRE resistance of vancomycin-resistant Staphylococcus aureus (VRSA) and Enterococcus in staphylococci at home and abroad.

Objective to observe the effect of denervation of sympathetic nerves on the regeneration of peripheral nerves after injury. Methods One cervical middle sympathetic ganglion was excised, and bilateral median nerves were cut and anastomosed. At 1, 2, 4 and 8 weeks after operation, the complex action potential (CMAP) of bilateral superficial flexor toe muscle, the sensory nerve activity potential (SNAP) of median nerve, the myelinated fiber count and ultrastructure observation far from the anastomosis, the maximum muscle contraction force of superficial flexor toe muscle and its muscle wet weight were measured, and the above indexes were compared bilaterally. Results All indexes (19.9 μ V ± 2.7 μ V, 11.8 mV ± 1.7 mV) on the experimental side were lower than those on the control side (25.1 μ V ± 1.8 μ V, 18.0 μ V ± 1.0 μ V) (all P<Conclusion Sympathetic nerve denervation is not conducive to the regeneration of peripheral nerve after injury, and the elimination of basal tension of peripheral nerve nutrient vessels may lead to nerve denervation. Sympathetic nerve may have nutrition and protection effects on denervated skeletal muscle.

Objective to observe the effect of chitosan combined with tacrolimus (FK506) sustained-release sheath combined with 3 mm small space to bridge nerve on nerve regeneration.Methods 45 male SD rats were randomly divided into 3 groups, and the sciatic nerve regeneration chamber model was made by cutting off bilateral sciatic nerves, and the gap between the broken ends was 3mm. The bridging materials used in the experiment were: silicone tube, chitosan sheath tube and chitosan combined with FK506 sustained-release sheath tube.The scar formation and absorption around the bridging materials were observed at 6, 8 and 12 weeks after operation, respectively, and the regeneration and functional recovery of sciatic nerve in each group were compared by neuroelectrophysiological, histological observation, image analysis and wet weight detection of gastrocnemius muscle. Results The gross observation of postoperative specimens showed that the adhesion between the regeneration chamber and the surrounding tissues was heavy in the control group; The nerve bridges in the chitosan sheath group and the chitosan compound FK506 sheath group were easily peeled from the surrounding tissues, and the adhesion was slight. At 8 weeks, the bridging materials in the chitosan sheath group and the chitosan composite FK506 sheath group began to absorb; At 12 weeks, the bridging material in the chitosan sheath group and the chitosan composite FK506 sheath group was incomplete or only fragments remained, and the nerve continuity was established, and there was no obvious adhesion to the surrounding tissues. The motor nerve conduction velocity, composite muscle action potential and incubation period detection indexes of nerve regeneration were evaluated. The chitosan composite FK506 sheath group (10.2m/s±0.8 m/s,4.3mV±0.3mV,1.9mS±0.4mS) were significantly better than the control group (4.2mS±0.5mS,1.2mV±0.3mV,7.5mS±0.4mV), Chitosan sheath group (9.5 ms±0.3 ms, 2.7 mV±0.3 mV, 3.1 ms±0.4 ms), P<Conclusion Chitosan compound FK506 sustained-release sheath was used to bridge the sciatic nerve of rats, and the degradation started after stable in vivo for more than 2 months, which can significantly promote nerve regeneration and function recovery, and the degradation products were polysaccharides, which did not affect the microenvironment of nerve regeneration.

Objective to investigate the inhibitory effect and mechanism of alphastatin, a 24 amino acid fragment at the end of human fibrinogen α chain, on the angiogenesis of human umbilical vein-derived endothelial cells (ECV304). Methods ECV304 cells were cultured in vitro, and the effects of alphastatin on their migration, proliferation and tubular structure formation in vitro were measured. The expression of sphingosine kinase (SPK) mRNA in ECV304 cells was qualitatively detected by reverse transcription polymerase chain reaction (RT-PCR). ECV304 cells were treated with 10, 100 and 1000 nmol/L alphastatin, and the cellular protein was extracted. The activity of SPK enzyme in ECV304 cells was detected by adenosine triphosphate (ATP). Results The number of ECV304 cells migrating in different concentrations of alphastatin was (103 ± 4), (75 ± 3) and (13 ± 1), respectively, which was lower than that in the control group (131 ± 4).<0.05. When the concentration of alphastatin was 100 nmol/L and 1000 nmol/L, the area of formation of tubular structure was (1509±30) μ m2/visual field and (1301±20) μ m2/visual field, respectively, which were also significantly lower than that of the control group (2996±31) μ m2/visual field, both P<0.05. The effect of alphastatin on the proliferation of ECV304 cells was not statistically significant. The expression of SPK mRNA in ECV304 cells was confirmed by RT-PCR. Compared with the control group, alphastatin reduced the production of sphingosine 1-phosphate (S1P) in ECV304 cells, and the effect was most obvious when the concentration of alphastatin was 100 nmol/L and the action time was 12 h. Conclusion In vitro experiments showed that alphastatin can significantly inhibit the angiogenesis of ECV304 cells, which is closely related to the decrease of SPK activity and S1P production.

Objective to construct a recombinant adenovirus vector carrying hypoxia-inducible factor-1 α (HIF-1 α) gene and to explore the therapeutic effect of HIF-1 α on focal cerebral ischemia in rats.Methods A recombinant adenovirus (ad-HIF-1 α) carrying hypoxia-inducible factor-1 α and green fluorescent protein (GFP) was constructed by AdEasy System and identified by PCR. The rat middle cerebral artery ischemia-reperfusion model was established by suture method, which was divided into three groups: ad-HIF-1 α, adenovirus empty vector (Ad) and normal saline (NS); AD-HIF-1 α, Ad and NS were injected into the ischemic lateral ventricle of model rats, and the distribution and green fluorescence duration of AD-HIF-1 α, the neurological deficit score of the three groups of rats and 2,3,5-triphenyltetrazolium chloride (TTC) staining were observed to evaluate the therapeutic effect of AD-HIF-1 α on cerebral ischemia. Results Under fluorescence microscope, the expression of green fluorescent protein gradually expanded to the part away from the lateral ventricle, and the fluorescence was the strongest at 14 d, then gradually decreased, and basically disappeared at 28 d. The neurological deficit score of AD-HIF-1 α treatment group was 2.4±0.5 at 24 h, which was not statistically significant compared with Ad group (2.6±0.5) and NS group (2.7±0.7) (P>0.05); The neurological deficit scores were 1.6±0.7 and 0.9±0.6 in the 48-hour and 72-hour AD-HIF-1 α treatment groups, respectively, compared with those in the Ad group (2.9±0.6 and 3.2±0.6, respectively) and the NS group (3.0±0.7 and 3.2±0.8, respectively) (P<0.05); TTC staining of brain tissue at 72 h showed that the infarct volume of AD-HIF-1 α treatment group was 81.2 mm3±1.4 mm3, which was statistically significant compared with that of Ad group (173.9 mm3±1.3 mm3) and NS group (171.7 mm3±6.2 mm3) (P<Conclusion Ad-HIF-1 α has a certain therapeutic effect on focal cerebral ischemia in rats, which lays a foundation for further research and clinical application of HIF-1 α gene.

Objective to investigate the signal regulation of tyrosine protein phosphatase and Shp-2 in the formation of neuromuscular junction. Methods Mouse C2C12 myoblasts were cultured and differentiated into mature myotube cells. The effects of tyrosine phosphatase and Shp-2 on the activation of muscle-specific receptor tyrosine kinase (MuSK) and the clustering of acetylcholine receptor (AChR) were detected by immunoprecipitation, immunoblotting, RNA blocking (RNAi) and microfluorescence. Results pervanadate, an inhibitor of tyrosine protein phosphatase, increased the activity of MuSK and increased the agrin-independent aggregation of AChR, which increased by 6.7 times (6.43 clusters/cell) compared with the control group (0.96 clusters/cell) (P<0.01); At the same time, pervanadate also increased Agrin-dependent AChR aggregation; Screening by immunoblotting showed that Shp-2 was the main tyrosine protein phosphatase of mouse muscle cells; The activity of MuSK and AChR aggregation increased when the expression of Shp-2 protein was blocked. Conclusion When the signal of tyrosine protein phosphatase including Shp-2 was inhibited, the activity of MuSK and AChR aggregation increased; When activated, MuSK activity and AChR aggregation decrease.

Objective to study the characteristics of respiratory tract involvement in recurrent polychondritis (RP). Methods the clinical manifestations, respiratory function test, chest CT, bronchoscopy and their correlation were retrospectively analyzed in patients with respiratory tract involvement and uninvolved RP. Results Among 38 patients with respiratory tract involvement, 20 were males and 18 were females, the onset age was 45 ± 11 years old (27~71 years old), with symptoms such as cough, sputum, hoarseness, holding breath, wheezing, dyspnea, etc. 18 patients underwent respiratory function test, including 10 cases with obstructive ventilatory dysfunction and 7 cases with mixed ventilatory dysfunction; Compared with RP patients without respiratory tract involvement, patients with respiratory tract involvement FEV1 (1.4 L ± 0.23 L vs 2.5 L ± 0.09 L, P =0.001), FEV1/FVC (46.0 ± 4.86 vs 83.7 ± 2.24, P =0.000), PEF (3.3 L/s ± 0.67 L/s vs 6.9 L/s ± 0.52 L/s, P =0.006), FEF50/FIF50 (0.3 ± 0.08 vs 1.3 ± 0.51, P =0.010), MMEF25~75 (0.4 L/s ± 0.18 L/s vs 2.8 L/s ± 0.73 L/s, P =0.010) All decreased significantly; Respiratory flow velocity volume loop showed the decrease of expiratory peak flow velocity and the formation of expiratory phase plateau.Chest CT examination in 27 cases showed airway stenosis in 11 cases and tracheal wall thickening in 8 cases.Bronchoscopy in 23 cases showed mucosal inflammation in 16 cases,disappearance of cartilage ring in 6 cases,airway collapse in 7 cases,positive airway stenosis in 15 cases,left and right main bronchus stenosis in 13 and 12 cases,respectively.Conclusion Respiratory function test is a sensitive examination to detect airway involvement in RP patients early.

Objective to explore the application value of cerebral angiography in the operation of cerebrovascular diseases.Methods Cerebral angiography was performed in 38 patients with cerebrovascular diseases.Among 38 cases, 21 were males and 17 were females, aged 3~53 years, with an average of (34±9) years old.Among 38 cases, 27 cases were arteriovenous malformation (AVM), the size of the malformed vascular mass was 2~8 cm, and 7 cases (25.9%) were huge AVMs (diameter ≥6 cm); There were 11 cases of aneurysms, including 3 cases of giant aneurysms (diameter ≥2.5 cm). The Hunt-Hess classification before operation was as follows: grade 1 in 4 cases, grade 2 in 4 cases and grade 3 in 3 cases. The patients were intubated through the right femoral artery after general anesthesia through tracheal intubation and reached the intracranial artery involved in operation. Angiography was performed after the lesion treatment. Results Among 38 cases, 9 cases of acute intracranial hemorrhage had no angiography before operation, but it was confirmed by angiography during operation, of which 7 cases were AVMs, and 2 cases were confirmed as aneurysms. 36 cases (94.7%) were confirmed by angiography to be satisfactory, and 1 case (9.0%) had residual ophthalmic aneurysm after clipping, and the aneurysm clip was readjusted; One patient (3.7%) had residual AVM in the posterior cranial fossa, no important arteries were clipped, no surgical death, and no angiography-related complications occurred. The intraoperative angiography time was 20~125 min, with an average of (53±22) min. Conclusion Intraoperative cerebral angiography can help physicians to detect residual aneurysm or AVM and occlusion of tumor-bearing artery in time, correct technical defects immediately, avoid reoperation, and reduce postoperative complications.

Objective to investigate the risk factors affecting symptomatic vasospasm after aneurysmal subarachnoid hemorrhage (SAH). Methods the clinical manifestations and imaging examinations of 186 patients with aneurysmal subarachnoid hemorrhage confirmed by imaging and lumbar puncture were retrospectively analyzed. Results 55 (29.6%) of 186 patients had symptomatic vasospasm. The incidence of symptomatic vasospasm in patients with repeated SAH episodes was significantly increased in Fisher grade Ⅲ patients with poor clinical condition (P<0.01); The incidence of symptomatic vasospasm in patients with sex, different age groups and different aneurysm treatment groups (surgical clipping or embolization) was not statistically significant (P>0.05). The use of antifibrinolytic drugs (AFD) after admission had no significant effect on the incidence of symptomatic vasospasm (P>0.05). Multivariate analysis showed that Fisher grade III [OR =2.549, 95% confidence interval (CI) 1.406-4.517], poor clinical condition (OR =2.342, 95% CI 1.320-4.159) and repeated SAH episodes (OR =2.492, 95% CI 1.394-4.448) were the risk factors affecting the occurrence of symptomatic vasospasm. Conclusion Fisher grade III, poor clinical condition and repeated SAH episodes were independent risk factors for symptomatic vasospasm. The occurrence of symptomatic vasospasm can be predicted according to the volume of subarachnoid hemorrhage, clinical condition at admission and the number of SAH episodes.

Objective to investigate the clinical characteristics of chronic periaortitis patients in China and improve the understanding of the disease. Methods the clinical data of 28 patients diagnosed with chronic periaortitis were retrospectively analyzed. Among 28 patients, male: female =4.5:1, mean age was 52.8 years. Results 20 (71.4%) of 28 patients were idiopathic retroperitoneal fibrosis, 5 (17.8%) were inflammatory abdominal aortic aneurysm, and 3 (10.7%) were peri-aortic retroperitoneal fibrosis. The most common symptoms were abdominal pain in 9 (35.7%), low back pain in 7 (25%), weight loss in 7 (25%), abdominal distension in 5 (17.8%) and edema of lower limbs in 5 (17.8%). Retroperitoneal soft tissue shadows were found by CT and MRI. 10 patients were diagnosed by pathological examination. 17 (85%) patients with idiopathic retroperitoneal fibrosis were found to have hydronephrosis by B-ultrasonography, and 7 cases were found to have abdominal aortic dilatation by B-ultrasonography. 8 of 20 cases were treated by surgery, 17 cases were treated with glucocorticoids and/or immunosuppressants and/or tamoxifen. 1 case was complicated with ankylosing 1 case with undifferentiated connective tissue disease, no other organ fibrosis, 5 cases with inflammatory abdominal aortic aneurysm had typical imaging manifestations, 3 of them were confirmed by pathological examination.3 cases with retroperitoneal fibrosis around aneurysm were misdiagnosed as idiopathic retroperitoneal fibrosis or abdominal aortic aneurysm.Conclusion Chronic periaortitis is a rare autoimmune rheumatism, and idiopathic retroperitoneal fibrosis is the most common disease.There are no specific clinical symptoms, but it can be combined with autoimmune rheumatism or autoantibodies, and the diagnosis depends on imaging evidence and pathological examination.Glucocorticoid combined with immunosuppressant or tamoxifen can alleviate the disease.

Objective to establish a method of transfection of recombinant human vascular endothelial growth factor (VEGF) 165 gene into rat bone marrow mesenchymal stem cells (MSCs), to investigate the effects of myocardial transplantation on cardiac function and angiogenesis in patients with ischemic heart disease, and to compare the efficacy of combination therapy with gene or cell therapy alone. Methods Wistar inbred rat MSCs were obtained by density gradient centrifugation-adherent culture method, and pcDNA31-hVEGF165 was transferred into the cells with liposomes, and the expression of VEGF in the latter cells was detected by ELISA, RT-PCR and Western blot. Wistar inbred rats were used to establish myocardial ischemia model and randomly divided into 4 groups (12 rats in each group). Two weeks after the establishment of myocardial infarction model, MSC transfected with VEGF165 gene in the combined group was transplanted in the myocardial infarction area, the same amount of MSC in the cell group was transplanted, the genome was injected with liposome-pcDNA31-VEGF165 DNA complex, and the control group was injected with equal volume culture medium; Another 12 rats with unligated coronary arteries were selected as sham operation group. After 4 weeks of cell transplantation, cardiac function was measured by Buxco system; Then the animals were sacrificed, the myocardial samples were taken, and the myocardial infarction area was measured; The survival and differentiation of transplanted cells were determined by immunohistochemical double staining with 5-bromodeoxyuracil (Brdu) and troponin T; The angiogenesis was detected by factor VIII staining, and the expression of VEGF165 gene was detected by RT-PCR. Results (1) pcDNA3.1-hVEGF165 gene was stably expressed by liposome transfection in rat MSC; (2) After 4 weeks of transplantation, the myocardial infarction size of the combined group (27.8%±3.0%) was significantly lower than that of the cell group (37.0%±10.1%) and the genome group (37.1%±5.2%, both P<0.05), and the improvement of cardiac function was better than that of the cell group and the genome group; (3) The capillary density (40.2±5.5 per visual field) in the combined group was higher than that in the cell group (27.2±6.3, P<0.01) and the control group (18.5±5.8, P<0.01), and there was an increasing trend compared with that in the genome group (35.8±7.7) (P =0.189); (4) Double staining of Brdu and Troponin T showed that the number of myocardial cells in the myocardial infarction area of each treatment group was more than that of the control group to different degrees; (5) The expression of VEGF gene in vivo (relative content of hVEGF mRNA 0.18±0.04) in the combination group was higher than that in the genome (0.10±0.03, P<0.01). Conclusion MSC transfected with VEGF gene can reduce the size of myocardial infarction and improve the cardiac function significantly caused by coronary artery ligation in rats, and its curative effect is better than that of gene or cell therapy alone, which provides a theoretical basis for the combination of cell and gene therapy in ischemic heart disease.

In the process of building a well-off society in China, the problem of national health needs is becoming increasingly prominent, and the contradiction between the expanding medical and health needs and the limited health resources is intensifying. How to effectively use the existing medical and health resources to meet the medical and health needs of 1.3 billion people on the premise of ensuring that everyone enjoys health is a difficult problem for us.

Toll protein was first discovered in Drosophila, and it is an essential component protein for regulating the development of dorso-abdominal body axis during embryonic development of Drosophila. Later, it was discovered that it is an important receptor for Drosophila to play an anti-microbial infection role in natural immunity. In 1997, Medzhitov et al. [1] first discovered human Toll protein homologous to Drosophila, and named it toll-like receptor (TLR). It can recognize pathogens, initiate innate immunity at the early stage of pathogen invasion, trigger inflammatory response and play an anti-pathogenic role. In the family of toll-like receptors, the structure of TLR-4 and its involvement in pro-inflammatory response, promote immune cell maturation and differentiation, and regulate immune response have been clearly studied. Recently, the role of TLR in non-pathogenic microbial inflammation such as myocardial ischemia-reperfusion injury has gradually attracted people's attention, It is found that it plays an important role in some inflammatory responses of myocardial ischemia-reperfusion injury. The signal transduction mechanism of TLR-4 and its research progress in myocardial ischemia-reperfusion injury and myocardial protection are reviewed as follows.

Colorectal cancer is one of the most common cancers, and its cause has not been completely elucidated. Previous studies have shown that the combination of calcium and vitamin D can not only improve bone metabolism, but also promote intestinal blood circulation, improve intestinal metabolism, and reduce the incidence of colon cancer and rectal cancer. However, Jean Wactawski-Wende of State University of New York at Buffalo raised questions about the combination of calcium and vitamin D can prevent colorectal cancer,<The New England Journal of Medicine reported a 7-year, large-sample, randomized, controlled, double-blind study systematically investigating the association of combined calcium and vitamin D with colorectal cancer (N Enng J Med, 2006, 354: 684-696).

Age-related macular degeneration (AMD) is the first blinding disease in developed countries and Caucasus, and it is also a common blinding eye disease in middle-aged and elderly people in China.The emergence of drusen between the inner layer of Bruch membrane and the basement membrane of RPE is an early sign of the disease.The specific cause of this disease is still unknown, but it may be related to oxidative damage, genetic and nutritional factors.

perfluorocarbon (PFC) is a kind of compound formed by replacing hydrogen atoms with fluorine atoms in hydrocarbons. PFC is a colorless, odorless and transparent liquid at room temperature. The volatilization rate is slightly faster than that of water, and its physical and chemical properties are extremely stable, and it is inmiscible with water, blood, lipids and other mediums.PFC has the characteristics of high gas solubility, fast carrying and releasing (the dissolution and release time of O2 and CO2 is 1/3 and 1/7 of that of hemoglobin, respectively), low surface tension, high specific gravity, moderate volatility, good histocompatibility, and basically does not absorb or metabolize in vivo. It is an ideal liquid respiratory medium at present. It has been used in complete fluid ventilation (TLV) and partial fluid ventilation (PLV) for the treatment of acute lung injury (ALI) /acute respiratory distress syndrome (ARDS) [1]. At present, the exact therapeutic mechanism of PFC is still unknown, but most of them believe that it is related to its special physicochemical properties and anti-inflammatory effects. IL-8 is secreted by alveolar type II epithelial cells (ATII cells) It has potent chemotactic and activating effects on polymorphonuclear leukocytes (PMN). This paper will investigate whether PFC can protect tumor necrosis factor α (TNF-α) from attacking ATII cells in vitro and reduce the release of inflammatory molecule IL-8.

With the advancement of detachable coil embolization technology and the continuous upgrading of detachable coil embolization system, the indications of endovascular interventional treatment of intracranial aneurysm in the treatment of ruptured intracranial aneurysm have been continuously expanded, and the understanding of endovascular interventional treatment by doctors and patients in related disciplines has increased, so that more patients with intracranial aneurysm have been cured by endovascular interventional therapy. From April 2004 to January 2005, 63 patients with Hunt-Hess grade Ⅰ ~ Ⅴ ruptured aneurysm and 64 intracranial aneurysm were treated in the Department of Neurosurgery of the Second Affiliated Hospital of China Medical University and Beijing Institute of Neurosurgery, and 50 of them were treated with detachable coil embolization in the acute phase (within 3 days). The results are reported below.

A 36-year-old male was admitted to the hospital for 3 years due to recurrent periumbilical pain accompanied by dizziness and fatigue. Three years ago, he developed abdominal distension and abdominal pain without obvious inducement, which were obvious after eating, mainly around the umbilical cord, and could be relieved by himself. He was usually accompanied by dizziness and fatigue. The blood pressure of the upper limbs was measured as high as 220/120 mm Hg (1 mm Hg =0.133 kPa). Digital subtraction angiography (DSA) of the aorta in another hospital showed that the left renal artery was stenotic, and the left renal artery was balloon dilated + stenting (PTA + stenting). The blood pressure could be controlled at 160/95 mm Hg after taking medication. After 1 year, the blood pressure rose to 190/110 mm Hg. Follow-up DSA showed that the right renal artery was stenotic and the left renal artery was occluded, and the right renal artery was PTA + stenting again. The postoperative blood pressure fluctuated at 165/110 mm Hg.