Feasibility study on low-dose technique for coronary artery angiography in overweight patients / 医疗卫生装备

Objective To explore the feasibility of low-tube-voltage and low-concentration contrast agent applied to coronary computed tomography angiography (CTA) in the overweight patients. Methods Totally 83 overweight patients with suspected coronary heart disease who underwent coronary artery angiography were randomly assigned into two groups. Group A used 100 kVp and ioversol-320 mg/ml, and Group B received 120 kVp and iopamidol-370 mg/ml. Both the groups went through prospectively ECG-gated scanning. The two groups were compared on the image quality, radiation dose, iodine intake and coronary artery segments scores. Results The effective radiation dose and iodine intake in Group A were significantly lower than those in Group B (P<0.05). Group A had the coronary artery CT value and image noise lower significantly than Group B (P<0.05). No significant differences in signal to noise ratio, contrast to noise ratio and coronary artery segments scores were observed between the two groups (P>0.05). Conclusion For coronary artery CTA in the overweight patients, low-tube-voltage and low-concentration contrast agent still preserves the image quality, as well as significantly reduces the radiation dose and iodine intake.

Changes in plasticity of rat hypothalamic neurons and astrocytes in humid and hot environment / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the changes in the plasticity of the neurons and astrocytes in the paraventricular nucleus (PVN) and supraoptic nucleus (SON) of the hypothalamus of rats exposed to a humid and hot environment.</p><p><b>METHODS</b>The rats were subjected to stimulation with a humid and hot environment for 120 min in a climate chamber (dry bulb temperature of 40.0-/+0.5 degrees C with relative humidity of 60-/+5%). During the exposure, the behavioral responses of the rats were observed, and the changes in the expressions of Fos and GFAP in the PVN and SON in response to the exposure evaluated using immunohistochemical ABC methods.</p><p><b>RESULTS</b>Exposure to a humid and hot environment caused restlessness and agitation in the rats, which showed increased respiratory frequency and scratching of the face with the forelimbs. Two rats died after the 120-min exposure. Significantly increased expressions of Fos and GFAP were detected in the PVN and SON following the exposure as compared with the control group.</p><p><b>CONCLUSION</b>The neurons and astrocytes in the PVN and SON both participate in the regulation of responses to exposure to a humid and hot environment.</p>

Morphology research of the rat sciatic nerve bridged by collage-heparin sulfate scaffold / 中华外科杂志

<p><b>OBJECTIVE</b>To observe the treating effect of collage-heparin sulfate after the 10 mm rat sciatic nerve defect was bridged by it.</p><p><b>METHODS</b>A new kind of nervous tissue engineering scaffold was produced by freeze-drying technique from collagen-heparin sulfate. Thirty-two SD rats were randomly divided into A, B, C and D groups. Sciatic nerve defect in group A was bridged by collagen-heparin sulfate. In group B, sciatic nerve was bridged by auto-nerve transplantation. Group C was the blank control group. Animals in group D were normal. And 10 mm sciatic nerve defect was bridged in the experiment. Thirty-six weeks after the operation, the experimental animals were detected by HRP labeled retrograde trace, HE staining, toluidine staining, silvering staining, S100, GAP-43 and NF immunohistological staining, MBP immunofluorescence staining and transmission electron microscope to observe the nerve regeneration inducing effect of this new scaffold.</p><p><b>RESULTS</b>Nine months after operation, the collage-heparin sulfate scaffold was replaced by newly regenerated nerve. The number of HRP labeled spinal cord anterior horn cells and the area of sensation nerve fiber at the posterior horn were similar with that was repaired by auto-nerve. GAP-43, NF and S100 labeled regenerated nerve fiber had passed the total scaffold and entered the distal terminal. The regenerated nerve fibers were paralleled, lineage arranged, coincide with the prearranged regenerating "channel" in the collagen-heparin sulfate scaffold. MBP immunofluorescence staining also proved that the newly regenerated nerve fiber could be ensheathed. In the experimental group, the area of myelinated nerve fiber and the thickness of the myelin sheath had no obvious difference with that of the group repaired by auto-nerve, except that the density of the regenerated myelinated sheath fiber was lower than that of the control group.</p><p><b>CONCLUSION</b>Nervous tissue engineering scaffold produced by collagen-heparin sulfate can guide the regeneration of nerve fibers. The nerve function recovers fine. This kind of material has great application potential.</p>