Twenty-four-hour real-time continuous monitoring of acute focal cerebral ischemia in rabbits based on magnetic inductive phase shift.

BACKGROUND: As a serious clinical disease, ischemic stroke is usually detected through magnetic resonance imaging and computed tomography. In this study, a noninvasive, non-contact, real-time continuous monitoring system was constructed on the basis of magnetic induction phase shift (MIPS) technology. The "thrombin induction method", which conformed to the clinical pathological development process of ischemic stroke, was used to construct an acute focal cerebral ischemia model of rabbits. In the MIPS measurement, a "symmetric cancellation-type" magnetic induction sensor was used to improve the sensitivity and antijamming capability of phase detection. METHODS: A 24-h MIPS monitoring experiment was carried out on 15 rabbits (10 in the experimental group and five in the control group). Brain tissues were taken from seven rabbits for the 2% triphenyl tetrazolium chloride staining and verification of the animal model. RESULTS: The nonparametric independent-sample Wilcoxon rank sum test showed significant differences (p < 0.05) between the experimental group and the control group in MIPS. Results showed that the rabbit MIPS presented a declining trend at first and then an increasing trend in the experimental group, which may reflect the pathological development process of cerebral ischemic stroke. Moreover, TTC staining results showed that the focal cerebral infarction area increased with the development of time CONCLUSIONS: Our experimental study indicated that the MIPS technology has a potential ability of differentiating the development process of cytotoxic edema from that of vasogenic edema, both of which are caused by cerebral ischemia.

[Preparation and characterization of monoclonal antibodies against human secretory leukocyte protease inhibitor].

AIM: To prepare and identify monoclonal antibodies(mAbs) against human secretory leukocyte protease inhibitor (hSLPI). METHODS: BALB/c mice were immunized with hSLPI, and hybridoma cell lines were obtained by fusing mouse spleen cells with myeloma NS-1 cells. The specificity of mAbs were characterized by ELISA, Western blot, immunohistochemical staining, flow cytometry(FCM) and confocal laser scanning microscopy(CLSM). RESULTS: Four hybridoma cells which secreted the mAbs to hSLPI were obtained. 4 mAbs were IgM. Western blot analysis showed that the mAbs could recognize a target molecule with relative molecular mass of 12 000. Immunohistochemical staining revealed that the reactivities of 4 mAbs to the epithelial cells in lung and colon tissues, mast cell-like cells in lung, colon, tonsil and prepuce tissues were positive. The result of FCM showed that the 4 mAbs recognized SLPI expressed in A549 cells. CLSM examination confirmed that the fluorescent markers were mainly localized in the cytoplasm of A549 cells. CONCLUSION: The mAbs against hSLPI are prepared successfully, which provides valuable tool for studies on allergic and inflammatory diseases.