Selection of MR sequences in diagnosis of fetal spinal cord malformation / 中国医学影像技术

Objective: To explore the value and selection of MR sequences in diagnosis of fetal spinal cord and spinal deformity. Methods: Data of 30 fetuses underwent prenatal ultrasound screening and history abnormal fetal spinal cord and 48 h adept MRI (Haste, Trufi and SWI) targeted examination about fetal spine were retrospectively analyzed, and compared with postpartum (production or induced labor) within 6 months of follow-up Results: (image, surgery or autopsy). The diagnosis coincidence rate of MRI and ultrasound, and MR sequence selection for different pathological changes were compared. Results: Among 30 fetuses, 7 were proved without deformity, 15 were found with vertebral malformation (split vertebra, half vertebra, incomplete septa, sacrococcygeal vertebra dysplasia), 5 with lower spinal cord, 3 with spina bifida or myelomeningocele, 4 with spinal cord complex malformation. Prenatal MRI diagnosis were completely consistent with follow-up Results:. Two fetuses of vertebral deformity, 4 of low spinal cord and 1 of meningiocele, syenomyelia and longitudinal fissure were missed with prenatal ultrasound. MR Haste and Trufi sequences were satisfied in displaying the structure and deformity of fetal spinal cord, while SWI could clearly show fetal vertebral structure and deformity. Conclusion: MR Haste and Trufi are accurate in displaying abnormalities in fetal spinal cord and spinal canal, while SWI has unique value in describing vertebral deformity.

Advances of supercritical fluid chromatography in lipid profiling / 药物分析学报

Supercritical fluid chromatography (SFC) meets with great favor due to its high efficiency, low organic solvent consumption, and the specialty for the identification of the isomeric species. This review de-scribes the advances of SFC in targeted and untargeted lipid profiling. The advancement of the SFC in-struments and the stationary phases are summarized. Typical applications of SFC to the targeted and untargeted lipid profiling are discussed in detail. Moreover, the perspectives of SFC in the lipid profiling are also proposed. As a useful and promising tool for investigating lipids in vitro and in vivo, SFC will predictably obtain further development.

Intraperitoneal injection via a paravertebral approach in rabbits / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore a simple and reliable method for intraperitoneal injection through a paravertebral approach in rabbits.</p><p><b>METHODS</b>Sixty New Zealand rabbits were randomized into conventional group and modified groups to receive intraperitoneal injections through conventional and paravertebral approaches, respectively. In the conventional group, the injection site was on the abdominal wall 3~4 cm lateral from the umbilicus bilaterally, while that in the modified group was located dorsally at L5/L6 level 3-4 cm lateral from the midline. Abdominal CT scan was performed in the post-injection rabbits, which were sacrificed after 24 h for abdominal dissection.</p><p><b>RESULTS</b>Success with a single puncture was achieved in 13 out of the 20 rabbits in the conventional group, and the rest required at least two punctures, with a mean rank sum of 23.50. With the modified approach, a single attempt was successful in all the 40 rabbits, with a mean rank sum of 34.0, showing a significant difference between the two groups (P<0.01). The success rates of a single injection differed significantly between the two groups (P<0.01). CT scan and abdominal dissection showed that the injection site with the modified approach was far away from the vital organs and large vessels with less peritoneal hyperemia and exudation.</p><p><b>CONCLUSION</b>Paravertebral intraperitoneal paracentesis is a convenient and reliable method for intraperitoneal injection in rabbits.</p>

Pathological study of cerebral amyloid angiopathy in rat models of Alzheimer's disease / 南方医科大学学报

<p><b>OBJECTIVE</b>To examine cerebral pathologies in cerebral amyloid angiopathy in a rat model of Alzheimer's disease.</p><p><b>METHODS</b>Rat models of Alzheimer's disease was established by stereotactic Aβ1-42 fiber injection in the bilateral hippocampus. The cognitive function of the rats was evaluated with water maze test. HE staining, Congo red staining and double-labeling indirect immunofluorescence were used to examine the dynamic distribution of Aβ fiber deposit in the brain.</p><p><b>RESULTS</b>The model rats showed significant differences from the control rats in the escape latency and the times of crossing platform in waster maze test. HE staining revealed a decreased number and degeneration of the granular cells with increased glial cells in the model rats. Congo Red staining showed that the Aβ fiber was deposited gradually in the small vessels in the brain parenchyma to cause thickening, stenosis or occlusion of the small vessels. Immunofluorescence staining detected Aβ fiber migration from the parenchyma to the walls of the small arteries in the rat models.</p><p><b>CONCLUSION</b>Cerebral amyloid angiopathy is a major pathological feature in Alzheimer's disease.</p>

Pathological findings of axonal injury in a rat model of experimental allergic encephalomyelitis / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the pathological changes of axonal injury in a rat model of experimental allergic encephalomyelitis (EAE).</p><p><b>METHODS</b>With HE, luxol fast blue and Bielschowsky staining, the expression of APP, MBP, SMI-32 and MBP in the brain and spinal cord of EAE rats using double-labeling indirect immunofluorescence.</p><p><b>RESULTS</b>Extensive cuffing lesions of inflammatory cell infiltrations were found in the brain and spinal cord of the rats, accompanied by multiple lesions of demyelination, axonal disarrangement with vesicular loss. SMI-32 staining identified numerous nonphosphorylated neurofilament, indicating the presence of axonal injury. Axonal oval bodies formed by APP accumulation were found in the white matters of the spinal cord 14 days after EAE, suggesting that neuraxial damage occurred in the early stage of EAE which was not synchronous with myelin loss.</p><p><b>CONCLUSION</b>Different levels of inflammation occur in different stages of EAE, and inflammatory cell infiltration is the most obvious at the peak of EAE. Axonal injury occurs in the early stage of EAE and progresses over the entire disease course.</p>