In order to study the regularity of shedding virus from infected SPF chickens and the formation of aerosol of H9N2 subtype AIV, SPF chickens were bred in a positive and negative pressure isolator. Aerosol samples were collected by AGI-30 (All Glass Impinger-30) extractor, and simultaneously trachea and cloaca samples were collected by tracheal swabs and cloacal swabs in different periods after challenged with vi- ruses. The above-mentioned samples were detected by HI, Dot-ELISA and RT-PCR methods. The results in- dicated that aerosols were isolated from the 4 days to the 43 days after inoculation. It was proved that H9N2 subtype AIV could copy themselves in respiratory passage and cloaca, and then could formation of aerosols. AIV H9N2 subtype could be isolated from cloacal and tracheal swabs 3 days after inoculation and lasted for 45 days, viruses were detected from all infected SPF chickens on 7 days.

Objective To assess and compare the effectiveness of gadolinium diethylenetriamine pentacetic acid(Gd-DTPA) solution and barium sulfate(BaSO4) suspension with different concentrations in improving the imaging quality of magnetic resonance cholangiopancreatography(MRCP). Methods The phantom study was carried out to determine the optimal concentration of Gd-DTPA and BaSO4 suspension used as an oral negative contrast agent in MRCP.The patients were grouped randomly and performed MRCP before and after using oral contrast agents in combination with intravenous injection of contrast agents.A comparison of the influence of BaSO4 suspension and Gd-DTPA with different concentrations on the signal intensity of the fluid in gastrointestinal tract on MRCP images was made.Results The phantom study showed that the dilution ratio 1∶10 of Gd-DTPA solution and 100%(W/V)BaSO4 suspension were the optimal concentrations in decreasing the signal intensity.In all patients the high signal intensity of the gastrointestinal fluid was completely suppressed after oral administration of Gd-DTPA diluted solution(P

Midbrain dopamine (DA) neurons play an essential role in modulating motor control. Defects in central DA neurons affect a wide range of neurological disorders including Parkinson's disease (PD). The greatest motivation in the field has been the potential use of DA neurons for cell transplantation therapy in Parkinsonian patients. Recent studies indicated that BMSCs could differentiate into DA neurons in vitro as neural stem cells (NSC) and embryonic stem cells (ESC) could. However, there are no direct evidences about functional DA neurons derived from BMSCs. According to the protocols which had been applicated in inducing neuronal stem cells and embryonic stem cells differentiate into DA neurons in vitro, the present study provides a protocol by using 50 micromol/L brain derived neurotrophy factor (BDNF), 10 micromol/L forskolin (FSK) and 10 micromol/L dopamine (DA) to induce BMSCs differentiate into DA neurons. After 2 weeks of differentiation, the cells expressed the character of neurons in ultrastructure. RT-PCR discovered mRNA of NSE (neuron specific enolase), Nurr1, Ptx3, Lmx1b and Tyrosine hydroxylase (TH) were positive. Immunocytochemistry staining indicated the ratio of TH-positive neural cells was significantly increased after induced 2 weeks (24.80 +/- 3.36) % compared to that of induction of 3 days (3.77 +/- 1.77) %. And the DA release was also different between differentiated and undifferentiated cells detected by high performance liquid chromatography (HPLC). That is to say BDNF and FSK and DA can induce BMSCs differentiate into DA neurons in vitro, and the transdifferentiated cells express mature neurons characters. BMSCs might be a suitable and available source for the in vitro derivation of DA neurons and cell transplantation therapy in some central neural system diseases such as PD.
Adult ; Aged ; Bone Marrow Cells ; cytology ; metabolism ; ultrastructure ; Brain-Derived Neurotrophic Factor ; pharmacology ; Cell Transdifferentiation ; drug effects ; genetics ; physiology ; Cells, Cultured ; Chromatography, High Pressure Liquid ; Colforsin ; pharmacology ; Dopamine ; metabolism ; pharmacology ; Female ; Humans ; Immunohistochemistry ; Male ; Mesenchymal Stromal Cells ; cytology ; metabolism ; ultrastructure ; Microscopy, Electron, Transmission ; Middle Aged ; Neurons ; cytology ; metabolism ; ultrastructure ; Phosphopyruvate Hydratase ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Tyrosine 3-Monooxygenase ; genetics ; metabolism ; Young Adult

To explore the effect of different doses of thrombopoietin on proliferation of bone marrow mesenchymal stem cells (MSCs) in mice, 20 Kunming mice (35 +/- 5 g) were divided randomly into 4 groups: low-dose TPO group, moderate-dose TPO group, high-dose TPO group and normal control group (n = 5). The experimental groups were subjected to intraperitoneal injections of TPO at a dose of 25, 50, 100 microg/kg, respectively, and normal control group were treated with saline at a dose of 0.1 ml/g per day for 5 days. The bone marrow was harvested on 12 hours after the final administration. The bone marrow nucleated cells (BMNCs) were counted and seeded at a density of 10(6) cells/cm(2). The colony-forming unit-fibroblast (CFU-F) of MSCs was cultured and evaluated. The CFU-F of MSCs underwent osteo-genic induction and adipogenic induction, and cytochemical and immunocytochemical staining were performed to verify their multipotential. CFU-F and the cell percentage of CD90(+), CD105(+), CD34(+) in BMNCs were analyzed by flow cytometry. The results showed that the number of BMNCs and the cell percentage of CD90(+), CD105(+), CD34(+) and CFU-F increased obviously in TPO groups as compared with the normal control group (p < 0.05). The number of BMNCs increased most obviously in the 50 microg/kg TPO group. However, there was no significant difference in number of CFU-F between 50 microg/kg and 100 microg/kg TPO group (p > 0.05). The CFU-F of MSCs in bone marrow had their osteogenic and adipogenic differentiation potentials in vitro. It is concluded that the number of BMNCs and the cell percentage of CD90(+), CD105(+) and CFU-F increased after administration with TPO. It means that TPO can enhance MSCs to proliferate in bone marrow. However, the number of BMNCs and CFU-F can not increase with the increase of TPO dose.
Animals ; Bone Marrow Cells ; cytology ; Cell Proliferation ; drug effects ; Cells, Cultured ; Dose-Response Relationship, Drug ; Mesenchymal Stromal Cells ; cytology ; Mice ; Thrombopoietin ; pharmacology

BACKGROUNDDiabetes mellitus is associated with coronary dysfunction, contributing to a 2- to 4-fold increase in the risk of coronary heart diseases. The mechanisms by which diabetes induces vasculopathy involve endothelial-dependent and -independent vascular dysfunction in both type 1 and type 2 diabetes mellitus. The purpose of this study is to determine the role of vascular large conductance Ca(2+)-activated K(+) (BK) channel activities in coronary dysfunction in streptozotocin-induced diabetic rats.

METHODSUsing videomicroscopy, immunoblotting, fluorescent assay and patch clamp techniques, we investigated the coronary BK channel activities and BK channel-mediated coronary vasoreactivity in streptozotocin-induced diabetic rats.

RESULTSBK currents (defined as the iberiotoxin-sensitive K(+) component) contribute (65 ± 4)% of the total K(+) currents in freshly isolated coronary smooth muscle cells and > 50% of the contraction of the inner diameter of coronary arteries from normal rats. However, BK current density is remarkably reduced in coronary smooth muscle cells of streptozotocin-induced diabetic rats, leading to an increase in coronary artery tension. BK channel activity in response to free Ca(2+) is impaired in diabetic rats. Moreover, cytoplasmic application of DHS-1 (a specific BK channel b(1) subunit activator) robustly enhanced the open probability of BK channels in coronary smooth muscle cells of normal rats. In diabetic rats, the DHS-1 effect was diminished in the presence of 200 nmol/L Ca(2+) and was significantly attenuated in the presence of high free calcium concentration, i.e., 1 mmol/L Ca(2+). Immunoblotting experiments confirmed that there was a 2-fold decrease in BK-b(1) protein expression in diabetic vessels, without altering the BK channel α-subunit expression. Although the cytosolic Ca(2+) concentration of coronary arterial smooth muscle cells was increased from (103 ± 23) nmol/L (n = 5) of control rats to (193 ± 22) nmol/L (n = 6, P < 0.05) of STZ-induced diabetic rats, reduced BK-b(1) expression made these channels less sensitive to intracellular Ca(2+), which in turn led to enhanced smooth muscle contraction.

CONCLUSIONSOur results indicated that BK channels are the key determinant of coronary arterial tone. Impaired BK channel function in diabetes mellitus is associated with down-regulation of BK-b(1) expression and reduction of the b(1)-mediated BK channel activation in diabetic vessels.

Animals ; Blotting, Western ; Coronary Vessels ; metabolism ; Diabetes Mellitus, Experimental ; metabolism ; physiopathology ; Diabetes Mellitus, Type 1 ; metabolism ; physiopathology ; Electrophysiology ; Large-Conductance Calcium-Activated Potassium Channels ; metabolism ; Male ; Muscle, Smooth, Vascular ; metabolism ; Rats ; Rats, Sprague-Dawley

OBJECTIVE: To evaluate the deviation of digital implant surgical guides during fabrication process in the Organical Dental Implant (ODI) system. METHODS: This study included two parts. The first part was the in vitro study. A resin block with a diagnostic template was used for the planning. After cone beam computed tomography (CBCT) scanning, a surgical guide with eight implants was virtually designed using the ODI system. The guide was milled by a 5-axial numerical controlled milling machine, and an optical scanning was taken to digitalize the guide to a standard tessellation language (STL) form. The STL data were then imported into an ODI software and registered with the original design. The deviation of the sleeves between the design and the STL was measured in the ODI software and set as the golden standard. Then the ODI examination table was used to measure the deviation of the guide during fabrication. Examiners A and B measured 10 times separately. The reliability and the validity of the examination table was calculated. The second part was the in vivo study: The deviation during fabrication of 12 guides designed and fabricated by the ODI system were measured using the examination table. RESULTS: The standard deviation of the deviation measured using the examination table by examiners A and B were all below 0.40 mm (for the shell reference points) and 0.71 degree (for the angles). No significant difference was found between the two examiners for any implant sites. The result of the examination table was larger than that of the software for the shell reference point (t-test, P<0.05), but no significant difference was found for the angle deviation (t-test, P>0.05). The 45 implants positions in the 12 guides for the in vivo study were examined using the examination table. The deviations at the shell reference points were (1.06±0.29) mm (0.42-1.75 mm), and at the implant tip were (1.12±0.48) mm (0.41-2.44 mm). The angle deviations were (1.42±0.70) degree (0.29-2.96 degree). CONCLUSION Deviation is unavoidable during the fabrication process of the guides. The examination table of the ODI system is a reliable and valid tool to measure the deviation during fabrication of the ODI guides. More studies should be designed to research the relationship between the fabrication deviation and the implant insertion deviation.
Computer-Aided Design ; Cone-Beam Computed Tomography ; Dental Implantation, Endosseous ; Dental Implants ; Imaging, Three-Dimensional ; Reproducibility of Results ; Surgery, Computer-Assisted