Cheung, RTF

Fong, GCY

Ho, SL

Ho, WY

Tsoi, TH

HKU Scholars Hub

Title Regional cerebral blood flow study in postictal psychosiscomplication complex partial seizureAuthor(s) Fong, GCY; Ho, WY; Tsoi, TH; Cheung, RTF; Ho, SLCitationThe 5th Medical Research Conference (MRC 2000), Hong Kong,China, January 2000. In The Hong Kong Practitioner, 2000, v. 22suppl. 2, p. 51Issued Date 2000URL http://hdl.handle.net/10722/46816Rights Creative Commons: Attribution 3.0 Hong Kong LicenseS-R-5Charge-dependent binding of polymeric IgA to human mesangial cells in IgA nephropathy (IgAN).Joseph CK Leung. Anita WL Tsang, TM Chan, KN Lai. Division of Nephrology, University Dept. of Medicine,QMH, HK.Objectives : The mechanism of polymeric IgA deposition in the kidney mesangium is poorly understood inIgA nephropathy (IgAN). It has been suggested that increased sialic acid content and anionic charge in polymericIgA molecules may be operational in the IgA deposition in t human mesangial cells (HMC). The presentstudy examined the binding of polymeric IgA with different surface charges to HMC. The characteristics ofbinding of IgA to HMC in the presence of polycation (poly-L-lysine) or polyanion (heparin) were alsoinvestigated.Methods : IgA were purified in sera from patients with IgAN and from healthy donors by jacalin affinitychromatography. IgA were further separated into polymeric and monomeric IgA by fast protein liquidchromatography (FPLC). Polymeric or monomeric IgA with different net charge on their surface were resolvedby ion exchange chromatography (1EC) with MonoQ column. The binding characteristics of polymeric andmonomeric IgA to HMC in the presence or absence of polycation or polyanion were examined by flow cytometry.Results : Two major peaks (Pk 1 & Pk2) were resolved when polymeric IgA from patients with IgAN wassubjected to anion exchange chromatography with MonoQ column. Pk 1 was eluted at 0.37 M NaCl and Pk 2was eluted at 0.42 M NaCl. Under identical condition, one major peak, Pk3 (eluted at 0.33 M NaCl), wasresolved in monomeric IgA. Polymeric IgA interacted with MonoQ exchanger stronger than monomeric IgAand the binding of polymeric IgA to HMC was significantly higher than that of monomeric IgA (p<0.05). IgAthat interacted strongly with ion exchanger (Pk2) also bound more to HMC when compared with IgA withweaker interaction with ion exchanger (Pkl) (p<0.01). The amount of Pk2 in polymeric IgA from patient wassignificantly higher than that of the healthy control (p<0.05). The presence of poly-L-lysine increased thebinding of polymeric IgA to HMC. The binding of polymeric IgA to HMC was decreased by pre-incubationwith heparin.Conclusions : The binding of IgA to HMC is charge-dependent. Polymeric IgA with the highest net negativecharge bind more to HMC. Pre-incubation with poly-anion decreased the binding of polymeric IgA to HMC.All these observation indicate the important role of anionic charge in mesangial IgA deposition.S-N-1Regional cerebral blood flow study in postictal psychosis complication complex partial seizureGCY Fong. WY Ho*, TH Tsoi@, RTF Cheung, SL Ho.Division of Neurology, University Department of Medicine, Queen Mary Hospital, Hong Kong.* Department of Nuclear Medicine, Queen Mary Hospital, Hong Kong.@ Department of Medicine, Pamela Youde Nethersole Eastern Hospital, Hong Kong.Postictal psychosis (PP) is an uncommon complication in patients with complex partial seizure (CPS). PP isassociated with furies of complex partial seizures and usually occurs after a short lucid interval. The analogyof memory loss due to Todd's palsy was postulated as the pathogenic mechanism without definite proof. Inthis communication, we reported a regional cerebral blood flow study in patients with PP. Three consecutivepatients with CPS complicated by PP were examined by cerebral Single Photon Emission ComputerizedTomography (SPECT) scan. We compared the cerebral SPECT scan performed during PP with that doneduring the interictal period. Regional hyperperfusion signals were seen in right temporal lobe (3/3) andcontralateral basal ganglia (2/3). Quantitative analysis showed the difference in the asymmetry index, rangingfrom 155.9% to 1167.8%. The hyperperfusion signs could implicate an abnormal subcortical electricalpropagation involving the left basal ganglia and right temporal lobe as the mechanism for PP.

Regional cerebral blood flow study in postictal psychosis complication complex partial seizure

http://hub.hku.hk/bitstream/10722/46816/1/52698.pdf

Regional cerebral blood flow study in postictal psychosis complication complex partial seizure

Abstract

Similar works

Full text

Available Versions

HKU Scholars Hub