Usage of reverse genetic techniques in the research area of the fundamental etiology of foot-and-mouth disease virus (FMDV), has resolved the issue about the function of viral gene of FMDV on genomic integer level. At present, a further recognition and apprehension for the molecular etiology of FMDV based on the development in reverse genetics was made. Combined with the research work in our labs, we reviewed international advances about the molecular pathogenic mechanism, the relationship be-tween virulence and variation in the genomes, influencing factors for the viral replication, and the develop-ment of new-type gene vaccine of FMD in this article, and propose the potential research aspects in reverse genetics of FMDV in the future.

Objective To evaluate the clinical efficacy of multiple stents placement in the management of hilar cholangiocarcinoma,especially in the complex cases of which the hepatic ducts are invaded.Methods Forty-five consecutive patients with hilar cholangiocarcinoma were treated with percutaneous transhepatic placement of two or three self-expandable metallic endoprostheses.The cause of hilar obstructions in these patients were all cholangiocarcinoma,including Bismuth classification type Ⅱ(n 12 ),Ⅲa(n 17),Ⅲb(n 10),and Ⅳ(n 6).Two or 3 stents were placed in the configuration of T,Y or X over the strictures.Results Stent placement with 2 or 3 endoprostheses was successful in all patients.All patients showed significant decrease in serum bilirubin level.The mortality rate within 30 days of stent placement was 2.2%(1/45).The mean survival and stent patency times were 215.3 d(26— 516 d)and 181.5 d(26—473 d),respectively.Conclusion Deploying of multiple metallic stents is an effective method to treat complex hilar cholangiocarcinoma,especially for the cases of which hepatic ducts are invaded:the henatic ducts should be drained as much as nossible.

In order to elucidate the effect of membrane stretch on ionic currents, we employed the whole-cell patch-clamp technique to investigate the effects of different kinds of stretch on voltage-dependent calcium currents in antrial circular smooth muscle cells of the guinea-pig. The membrane stretch induced by superfusing the smooth muscle cells with hyposmotic bath solution enhanced voltage-operated calcium current and activated inward holding current. The increase in calcium current occurred within 1 minute of superfusion and the sustained inward holding current was slowly activated after prominent cell swelling. Voltage-dependent calcium currents (Ica) were significantly increased by membrane stretch which was induced by cell swelling and cell inflation, but was not affected by direct longitudinal stretch (110～130%) using two electrodes.The results suggest that the cell membrane stretch can increase voltage-dependent calcium channel activity and the effect of stretch on calcium channels was related to the membrane tension and/or the direction of membrane stretch.

OBJECTIVE: To explore the distribution of inflammatory cells and positive expression of P-se- lectin glycoprotein ligand-1 (PSGL-1) in infant brainstem tissue from hand-foot-mouth disease related fatal brainstem encephalitis. METHODS: Twenty brainstem samples from infants suffered from brainstem en- cephalitis were collected as the experimental group. Ten brainstem samples from infants died of non- brain diseases and injuries were collected as the control group. The distribution of inflammatory cells and the expression of PSGL-1 in the two groups were examined by immunohistochemical method. The characteristics of the positive cells were observed. RESULTS: In brainstem tissue of the experimental group, there were sleeve infiltrations of inflammatory cells around the vessels and in the glial nodule. Microglia was the most and following was neutrophils around the vessels and in the glial nodule. There was a significant statistical difference among microglias, neutrophils and lymphocytes (P < 0.05). There was no sleeve infiltration in the control group. PSGL-1 protein was expressed widely in inflammatory cells in the experimental group, especially in the inflammatory cells around the vessels and in the glial nodule. But PSGL-1 positive staining could be observed significantly less in the control group comparing with the experimental group (P < 0.05). CONCLUSION Microglia is the main type of inflammatory cells involved in the progress of the fatal disease. Moreover, PSGL-1 could participate in the pathogenesis of hand-foot-mouth disease related fatal brainstem encephalitis.
Brain Stem/pathology* ; Encephalitis/pathology* ; Hand, Foot and Mouth Disease/pathology* ; Humans ; Infant ; Membrane Glycoproteins/metabolism* ; Microglia/pathology* ; Neutrophils/pathology*

The principle of Position Transformation Mechanical Ventilation (PTMV) was introduced briefly, and the mechanical structure and the intelligent control algorithm were studied. According to the principle and function requirement of PTMV, the mechanical structure of slip pole driven rocking chair(SPDRC) was proposed, the dynamics model of SPDRC was established, and the auto disturbance rejection controller was designed. The integrated model of control system was structured by using ADAMS and MATLAB, and the model validation and simulation were implemented. The simulation results indicate that the mechanical structure is feasible and the control process of ADRC is precise and steady.
Algorithms ; Models, Biological ; Posture ; Respiration, Artificial ; methods

To investigate the function of exogenous unsaturated fatty acids in hyposmotic membrane stretch enhancement of muscarinic current (ICCh) in antral circular smooth muscle cells of guinea pig, we recorded the membrane current with the conventional whole cell patch-clamp technique. I(CCh) elicited by 50 micromol/L carbachol (CCh) at the holding potential of 20 mV under isosmotic condition was taken as control. Hyposmotic membrane stretch increased I(CCh) to 226.0+/-21.0%. When the cells were pretreated with 5 micromol/L arachidonic acid (AA), linoleic acid (LA) or oleic acid (OA), I(CCh)was inhibited to 3.8+/-0.6%, 35.2+/-0.8% and 66.6+/-0.6% respectively. Hyposmotic membrane stretch increased I(CCh) to 106.0+/-2.5%, 173.2+/-6.8% and 222.1+/-11.0% of the control respectively. Five micromol/L AA inhibited hyposmotic membrane stretch-enhanced I(CCh) by 51.2+/-3.8%, while the control I(CCh) under isosmotic condition was inhibited by 96.2+/-1.6%. The results suggest that unsaturated fatty acids inhibited I(CCh) and the inhibitory effect is more significant when the unsaturation degree is increased. However, the unsaturated fatty acids are not involved in the increase of I(CCh) induced by hyposmotic membrane stretch.
Animals ; Fatty Acids, Unsaturated ; pharmacology ; Guinea Pigs ; Membrane Potentials ; drug effects ; Myocytes, Smooth Muscle ; cytology ; physiology ; Osmotic Pressure ; Patch-Clamp Techniques ; Pyloric Antrum ; cytology ; physiology ; Receptors, Muscarinic ; physiology ; Sodium Chloride

BACKGROUND: Adipose-derived mesenchymal stem cells (ADMSCs) have been reported to improve wound healing. However, type I collagen secreted by ADMSCs will contribute to scar formation. Therefore, inhibiting type I collagen secretion from ADMSCs will strengthen its clinical application. OBJECTIVE: To investigate the effect of 1,25(OH)2D3on secretion of type I collagen by ADMSCs and its mechanism. METHODS: Human ADMSCs were isolated by collagenase digestion, and identified by flow cytometry. ADMSCs at passage 4 were cultured in DMEM/F12 medium containing different concentrations of 1,25(OH)2D3(10-7, 10-8, 10-9, 10-10and 0 mol/L) respectively for 4 days. Then, the concentration of type I collagen in cell supernatant was measured by ELISA. Real-time PCR and western blot were used to detect the expression of Smad3 at mRNA and protein levels and phosphorylated protein Smad3 level in ADMSCs cultured with and without 1,25(OH)2D3. To analyze the contribution of Smad3 to the effect of 1,25(OH)2D3, Smad3 inhibitor was added to culture medium 30 minutes before adding 1,25(OH)2D3, and type I collagen in cell supernatant was detected by ELISA at 4 days after addition of SMAD3 inhibitor. RESULTS AND CONCLUSION: 1,25(OH)2D3inhibited the secretion of type I collagen by ADMSCs in a dose-dependent manner. The results of real-time PCR and western blot showed that the expression of Smad3 was upregulated by 1,25(OH)2D3, and the results of western blot showed that the phosphorylated Smad3 protein level in ADMSCs was significantly increased by 1,25(OH)2D3. Moreover, the inhibition of type I collagen secretion by 1,25(OH)2D3could be blocked by Smad3 inhibitor. These results indicate that 1,25(OH)2D3can inhibit the secretion of type I collagen from ADMSCs by up-regulating the expression of Smad3.

AIMTo investigate the effects of imidapril (IMI) on effective refractory period (ERP) and sodium current (I(Na)) of myocytes in ventricular noninfarction zone of healed myocardial infarction (HMI) in rabbit models.

METHODSRabbits with left coronary artery ligation were prepared and IMI (0.625 mg x kg(-1) x d(-1), 8 weeks) was orally administered. The ERP and sodium current were recorded.

RESULTSThe ERP in HMI heart was prolonged. The ERP in IMI group was lower significantly than that of HMI group. The I(Na) density of myocyte in HMI ventricle decreased obviously. V 1/2 of steady state inactivation of I(Na) shifted to hyperpolarization, and time constant (tau) of recovery from inactivation in HMI ventricular myocyte was longer than that of sham ventricular myocyte. I(Na) density in IMI group increased markedly as compared with that of HMI group.

CONCLUSIONIMI was shown to reverse the abnormal prolongation of ERP in rabbit heart with the HMI and increase I(Na) density. It may be the mechanism of IMI preventing against antiarrhythmia in healed myocardical infarction.

Angiotensin-Converting Enzyme Inhibitors ; pharmacology ; Animals ; Calcium Channels ; metabolism ; Female ; Heart Ventricles ; cytology ; Imidazolidines ; pharmacology ; Male ; Myocardial Infarction ; metabolism ; physiopathology ; Myocytes, Cardiac ; metabolism ; Rabbits ; Refractory Period, Electrophysiological ; drug effects

To investigate the relationship between cytoskeleton and hyposmotic membrane stretch-induced increase in muscarinic current, the role of actin microfilament in hyposmotic membrane stretch-induced increase in muscarinic current was studied with the whole-cell patch clamp technique in guinea-pig gastric myocytes. In this study, the muscarinic current was induced by carbachol (50 micromol/L) or GTPgammaS (0.5 mmol/L). The results showed that hyposmotic superfusate (202 mOsmol/L) increased carbachol-induced current (I(CCh)) by 145+/-27% and increased GTPgammaS-induced current by 183+/-30%; but in the presence of cytochalasin-B (Cyt-B, 20 micromol/L), an actin cytoskeleton disruptor, hyposmotic membrane stretch increased I(CCh) by 70+/-6%. However, hyposmotic membrane stretch induced increase in I(CCh) was potentiated to 545+/-81% by phalloidin (20 micromol/L), an actin microfilament stabilizer. The results demonstrated that hyposmotic membrane stretch increased the muscarinic currents induced by carbachol or GTPgammaS and that the actin microfilament is involved in the process in guinea-pig gastric myocytes.
Actin Cytoskeleton ; physiology ; Animals ; Carbachol ; pharmacology ; Female ; Guinea Pigs ; Male ; Membrane Potentials ; drug effects ; Myocytes, Smooth Muscle ; physiology ; Osmotic Pressure ; Patch-Clamp Techniques ; Pyloric Antrum ; cytology ; Receptors, Muscarinic ; physiology

OBJECTIVETo investigate the expression of the interferon-induced transmembrane-1 (IFITM1) gene in colorectal cancer (CRC) tissue and the serum anti-IFITM1 antibody responses of the patients and assess their value in clinical diagnosis of CRC.

METHODSSemi-quantitative RT-PCR was performed to detect IFITM1 mRNA expression in the specimens of normal colonic mucosa, CRC tissue, inflammatory polyps, adenomatous polyps, gastric cancer, esophageal carcinoma and liver cancer tissues. Serum samples were collected from the patients to detect anti-IFITM1 antibody responses using Western blotting. The clinicopathological features of the carcinoma expressing IFITM1 gene were analyzed.

RESULTSIFITM1 mRNA was expressed in 47.4 % (18/38) of the CRC specimens, a rate significantly higher than that in adenomatous polyps [15% (3/20)] and gastric cancer [4.8% (1/21)]; no obvious IFITM1 expression was found in normal colonic mucosa, inflammatory polyp, esophageal carcinoma or liver cancer tissues (P<0.001 or P<0.05). IFITM1 mRNA was strongly expressed in CRC at the expression level of 0.8048-/+0.2273, which was significantly higher than that in adenomatous polyps (0.4447-/+0.0989, P<0.001). No anti-IFITM1 antibody response was detected in healthy human sera, but in the CRC patients, the serum antibody response was detected at the rate of 36.8% (14/38), significantly higher than the rate of 9.5% (2/21) in gastric cancer (P<0.05). No antibody response was detected in esophageal carcinoma, liver cancer, inflammatory polyp or adenomatous polyps. Most of the IFITM1-expressing CRC had a diameter exceeding 5 cm, often invading the serous membrane with metastasis to the lymph nodes and the distant organs; these tumors were identified mostly as well-differentiated adenocarcinoma in Dukes stage C or D.

CONCLUSIONIFITM1 gene may play an important role in the pathogenesis, development and metastasis of CRC, and may serve as a potential biomarker for clinical diagnosis of CRC.

Antibodies ; blood ; Antigens, Differentiation ; Biomarkers, Tumor ; genetics ; metabolism ; Colorectal Neoplasms ; diagnosis ; genetics ; Humans ; Membrane Proteins ; genetics ; metabolism ; RNA, Messenger ; genetics ; immunology ; metabolism