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Gasteiger J, Bauerschmidt S, Burkard U, Hemmer MC, Herwig A, Von Homeyer A, Höllering R, Kleinöder T, Kostka T, Schwab C, Selzer P, Steinhauer L. Decision support systems for chemical structure representation, reaction modeling, and spectra simulation. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2002; 13:89-110. [PMID: 12074394 DOI: 10.1080/10629360290002253] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The choice of an appropriate structure coding scheme is the secret to success in QSAR studies. Depending on the problem at hand, 2D or 3D descriptors have to be chosen; the consideration of electronic effects might be crucial, conformational flexibility has to be of special concern. Artificial neural networks, both with unsupervised and with supervised learning schemes, are powerful tools for establishing relationships between structure and physical, chemical, or biological properties. The EROS system for the simulation of chemical reactions is briefly presented and its application to the degradation of s-triazine herbicides is shown. It is further shown how the simulation of chemical reactions can be combined with the simulation of infrared spectra for the efficient identification of the structure of degradation products.
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Morris HR, Al-Sarraj S, Schwab C, Gwinn-Hardy K, Perez-Tur J, Wood NW, Hardy J, Lees AJ, McGeer PL, Daniel SE, Steele JC. A clinical and pathological study of motor neurone disease on Guam. Brain 2001; 124:2215-22. [PMID: 11673323 DOI: 10.1093/brain/124.11.2215] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Despite over 40 years of intensive study, the cause of the high incidence of motor neurone disease (MND) on Guam, and the relationship between this disease and MND seen in the rest of the world are still uncertain. We present a series of 45 cases of Guamanian MND, which reaffirm the clinical similarity between this disease and MND seen in other countries. However, the occurrence of MND among the indigenous Chamorros of Guam is distinguished by four factors: (i) high prevalence; (ii) frequent familial occurrence; (iii) co-occurrence with the parkinsonism-dementia complex (PDC); and (iv) association with an unusual and distinctive linear retinopathy termed Guam retinal pigment epitheliopathy (GRPE). These distinguishing factors were not present in four non-Chamorros who resided on Guam when their MND symptoms occurred. Pathologically, the classical features of MND were seen in Guamanian Chamorro cases including ubiquitin inclusions. Neurofibrillary tangles were frequently seen. The neurofibrillary tangles appeared in the same distribution as described in the PDC but, unlike classical PDC, they were not usually associated with cell loss and occurred less frequently. While neurofibrillary tangle formation and the clinicopathological syndrome of MND may occur in parallel, observations from this series suggest that pathologically classical MND on Guam may occur independently of neurofibrillary degeneration and the clinical features of PDC.
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McGeer EG, Yasojima K, Schwab C, McGeer PL. The pentraxins: possible role in Alzheimer's disease and other innate inflammatory diseases. Neurobiol Aging 2001; 22:843-8. [PMID: 11754991 DOI: 10.1016/s0197-4580(01)00288-3] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Two short pentraxins, C-reactive protein and amyloid P, are found in association with the senile plaques and neurofibrillary tangles of Alzheimer disease (AD). Formerly thought to be made primarily if not solely in liver, recent work has shown that they are made not only in the brain but in other tissues such as heart and arteries. Their synthesis is markedly upregulated in affected brain regions in AD. Since they are known to activate the complement cascade in an antibody-independent fashion and chronic activation can cause destruction of host tissue, these pentraxins may be important initiators of an autodestructive process. As such, they may be prime targets for therapeutic intervention.
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Anderson SE, Schwab C, Stauffer E, Banic A, Steinbach LS. Hibernoma: imaging characteristics of a rare benign soft tissue tumor. Skeletal Radiol 2001; 30:590-5. [PMID: 11685483 DOI: 10.1007/s002560100405] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2001] [Indexed: 02/02/2023]
Abstract
Hibernoma is a rare benign soft tissue tumor of brown fat. Awareness of the MR imaging appearances of this lesion may allow for improved preoperative diagnosis or at least inclusion of hibernoma as a possible benign differential diagnosis prior to surgery.
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Beach TG, Kuo YM, Schwab C, Walker DG, Roher AE. Reduction of cortical amyloid beta levels in guinea pig brain after systemic administration of physostigmine. Neurosci Lett 2001; 310:21-4. [PMID: 11524148 DOI: 10.1016/s0304-3940(01)02076-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Overproduction of the peptide amyloid beta (Abeta) is thought to be a critical pathogenetic event in Alzheimer's disease (AD). Decreasing A production may therefore slow or halt the progression of AD. In vitro work has indicated that cholinergic muscarinic receptor agonists may reduce cellular production of Abeta. Here we show that systemic administration of physostigmine, an acetylcholinesterase inhibitor, lowers Abeta levels in vivo. Guinea pigs treated for 10 days with s.c. physostigmine had levels of cortical AbetaN-40 and N-42 which were 57% and 72%, respectively, of those in control animals. Levels of cortical beta-amyloid precursor protein were not significantly affected by drug treatment. These results suggest that cholinergic therapy may affect the course of AD by limiting Abeta accumulation.
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Klegeris A, Schwab C, Bissonnette CJ, McGeer PL. Induction of complement C9 messenger RNAs in human neuronal cells by inflammatory stimuli: relevance to neurodegenerative disorders. Exp Gerontol 2001; 36:1179-88. [PMID: 11404058 DOI: 10.1016/s0531-5565(00)00265-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Neurons express proteins of the classical complement pathway, including C9. Both the mRNA and protein levels for C9 are sharply upregulated in brain areas affected by Alzheimer's disease (AD). Since little is known about the signals that are responsible for this upregulation, we evaluated in human SH-SY5Y neuroblastoma cells the factors which stimulate C9 production. Interferon-gamma, phorbol myristate acetate and interleukin-6 all stimulated C9 mRNA expression but the inflammatory cytokines tumor necrosis factor-alpha, interleukin-1 beta, as well as the anaphylatoxin C5a and the bacterial lipopolysaccharide, were ineffective. Immunohistochemical analysis of postmortem human brains for C9 protein demonstrated its presence in many cortical pyramidal neurons in AD, Down's syndrome, the parkinsonism dementia complex of Guam and pallido-ponto-nigral degeneration, as well as in thalamic neurons of progressive supranuclear palsy and ballooned neurons of Pick's disease. Since C9 is required for the membrane attack complex of complement to become functional, interfering with signaling pathways that stimulate its production could offer new therapeutic strategies for treating various neurodegenerative disorders.
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Yasojima K, Schwab C, McGeer EG, McGeer PL. Complement components, but not complement inhibitors, are upregulated in atherosclerotic plaques. Arterioscler Thromb Vasc Biol 2001; 21:1214-9. [PMID: 11451754 DOI: 10.1161/hq0701.092160] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Complement activation occurs in atherosclerotic plaques. The capacity of arterial tissue to inhibit this activation through generation of the complement regulators C1 inhibitor, decay accelerating factor, membrane cofactor protein (CD46), C4 binding protein (C4BP), and protectin (CD59) was evaluated in pairs of aortic atherosclerotic plaques and nearby normal artery from 11 human postmortem specimens. All 22 samples produced mRNAs for each of these proteins. The ratios of plaque versus normal artery pairs was not significantly different from unity for any of these inhibitors. However, in plaques, the mRNAs for C1r and C1s, the substrates for the C1 inhibitor, were increased 2.35- and 4.96-fold, respectively, compared with normal artery; mRNA for C4, the target for C4BP, was elevated l.34-fold; and mRNAs for C7 and C8, the targets for CD59, were elevated 2.61- and 3.25-fold, respectively. By Western blotting and immunohistochemistry, fraction Bb of factor B, a marker of alternative pathway activation, was barely detectable in plaque and normal arterial tissue. These data indicate that it is primarily the classical, not the alternative pathway, that is activated in plaques and that key inhibitors are not upregulated to defend against this activation.
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Yasojima K, Schwab C, McGeer EG, McGeer PL. Generation of C-reactive protein and complement components in atherosclerotic plaques. THE AMERICAN JOURNAL OF PATHOLOGY 2001; 158:1039-51. [PMID: 11238052 PMCID: PMC1850354 DOI: 10.1016/s0002-9440(10)64051-5] [Citation(s) in RCA: 391] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
C-reactive protein (CRP) and complement are hypothesized to be major mediators of inflammation in atherosclerotic plaques. We used the reverse transcriptase-polymerase chain reaction technique to detect the mRNAs for CRP and the classical complement components C1 to C9 in both normal arterial and plaque tissue, establishing that they can be endogenously generated by arteries. When the CRP mRNA levels of plaque tissue, normal artery, and liver were compared in the same cases, plaque levels were 10.2-fold higher than normal artery and 7.2-fold higher than liver. By Western blotting, we showed that the protein levels of CRP and complement proteins were also up-regulated in plaque tissue and that there was full activation of the classical complement pathway. By in situ hybridization, we detected intense signals for CRP and C4 mRNAs in smooth muscle-like cells and macrophages in the thickened intima of plaques. By immunohistochemistry we showed co-localization of CRP and the membrane attack complex of complement. We also detected up-regulation in plaque tissue of the mRNAs for the macrophage markers CD11b and HLA-DR, as well as their protein products. We showed by immunohistochemistry macrophage infiltration of plaque tissue. Because CRP is a complement activator, and activated complement attacks cells in plaque tissue, these data provide evidence of a self-sustaining autotoxic mechanism operating within the plaques as a precursor to thrombotic events.
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Huber AM, Schwab C, Linder T, Stoeckli SJ, Ferrazzini M, Dillier N, Fisch U. Evaluation of eardrum laser doppler interferometry as a diagnostic tool. Laryngoscope 2001; 111:501-7. [PMID: 11224783 DOI: 10.1097/00005537-200103000-00022] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES Laser Doppler interferometry (LDI) of the eardrum allows noncontact optical analysis of its vibrations in response to sound. Although LDI has been widely used in research, it has not yet been introduced into clinical practice as an adjunctive test for otological workup. The aim of this study was to evaluate LDI as a diagnostic tool in the clinical sphere. STUDY DESIGN Prospective. METHODS A measurement system was developed based on a commercially available scanning He-Ne laser Doppler interferometer. The study included 129 eardrums of 79 subjects that were divided into 3 groups: 1) normal subjects and 2) patients with sensorineural and 3) conductive hearing loss (HL). All the patients suffering from conductive HL underwent ossiculoplasty, which allowed confirmation of the final diagnosis, and patients were assigned accordingly to the subgroups malleus fixation, incus luxation, and stapes fixation. RESULTS The modified LDI system allowed bilateral evaluation of a subject within 30 minutes. No significant difference between normal subjects and patients having sensorineural HL were found. However, it was possible to distinguish between normal subjects and patients with conductive HL. Furthermore, the system had the ability to differentiate between various middle ear diseases. These groups differed statistically significantly in terms of manubrium vibration amplitude and resonance frequency. In malleus fixation significant differences in tympanic membrane movement patterns were found. CONCLUSIONS Our LDI is applicable in clinical otological practice and serves as a valuable addition to the routine audiological investigations for preoperative evaluation of the mobility and integrity of the ossicular chain.
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Hodby JW, Jenkins TE, Schwab C, Tamura H, Trivich D. Cyclotron resonance of electrons and of holes in cuprous oxide, Cu2O. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3719/9/8/014] [Citation(s) in RCA: 142] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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61
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Bloch PD, Hodby JW, Jenkins TE, Stacey DW, Lang G, Levy F, Schwab C. Electronic transport and cyclotron resonance in 2H-PbI2. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3719/11/24/028] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Arai T, Ikeda K, Akiyama H, Shikamoto Y, Tsuchiya K, Yagishita S, Beach T, Rogers J, Schwab C, McGeer PL. Distinct isoforms of tau aggregated in neurons and glial cells in brains of patients with Pick's disease, corticobasal degeneration and progressive supranuclear palsy. Acta Neuropathol 2001; 101:167-73. [PMID: 11271372 DOI: 10.1007/s004010000283] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
We investigated isoform composition of aggregated tau protein in brains with Pick's disease (PiD), corticobasal degeneration (CBD) and progressive supranuclear palsy (PSP) by immunoblot analysis of sarkosyl-insoluble fractions of brain homogenates. We also examined the adjacent brain tissues immunohistochemically with a rabbit antibody, Ex10, which specifically recognizes exon 10 of tau. The Ex10 recognizes tau isoforms with four microtubule-binding repeats (4Rtau) but not those with three microtubule-binding repeats (3Rtau). Sarkosyl-insoluble tau from the brains of patients with CBD and PSP consisted of 4Rtau. Insoluble tau from the PiD brains contained both 3Rtau and 4Rtau, where 3Rtau predominated over 4Rtau. In brain tissues of CBD and PSP, Ex10 immunostained all neuronal and glial tau-positive structures. They included pre-tangles, astrocytic plaques, tuft-shaped astrocytes, and oligodendroglial coiled bodies. In PiD brains, astrocytic inclusions were also positive for 4Rtau. However, the majority of, if not all, Pick bodies and oligodendroglial tau inclusions were negative for 4Rtau. Such results suggest that, in neurons and oligodendroglia, tau isoforms involved in the pathological processes differ between CBD/PSP and PiD, and are thus disease specific. This contrasts with the astrocytic tau isoforms that accumulate similarly in all three disorders.
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63
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Yasojima K, Schwab C, McGeer EG, McGeer PL. Human neurons generate C-reactive protein and amyloid P: upregulation in Alzheimer's disease. Brain Res 2000; 887:80-9. [PMID: 11134592 DOI: 10.1016/s0006-8993(00)02970-x] [Citation(s) in RCA: 230] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
C-reactive protein (CRP) and amyloid P (AP) are pentraxins which are associated with many pathological lesions, including the amyloid deposits and neurofibrillary tangles (NFTs) of Alzheimer disease (AD). It has always been assumed that they are generated by liver and delivered to their sites of action by serum. Here we report by in situ hydridization, reverse transcriptase-polymerase chain reaction analysis, Western blotting and immunohistochemistry that the mRNAs and proteins of both CRP and AP are concentrated in pyramidal neurons and are upregulated in affected areas of AD brain. Controlling pentraxin production at the tissue level may be important in reducing inflammatory damage in AD.
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Renfrew C, Dickson R, Schwab C. Severe hypertension following ephedrine administration in a patient receiving entacapone. Anesthesiology 2000; 93:1562. [PMID: 11149468 DOI: 10.1097/00000542-200012000-00054] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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65
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Bloch PD, Meyer B, Schwab C. Sample thickness dependence of the exciton polariton absorption coefficient in Cu2O. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0022-3719/13/2/014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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66
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Tchapkui-Niat JM, Goltzene A, Schwab C. Paramagnetic defects in as-grown and iron doped CuInSe2. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0022-3719/15/22/013] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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67
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Biellmann J, Prevot B, Schwab C. First-order Raman line intensity ratio in GaAs: a potential lattice perfection scale. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0022-3719/16/6/019] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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68
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Lee CY, Ho J, Chow SN, Yasojima K, Schwab C, McGeer PL. Immunoidentification of gonadotropin releasing hormone receptor in human sperm, pituitary and cancer cells. Am J Reprod Immunol 2000; 44:170-7. [PMID: 11028904 DOI: 10.1111/j.8755-8920.2000.440307.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
PROBLEM To generate monoclonal antibodies specific to the receptor of gonadotropin releasing hormone (GnRH) for immunoidentification of the GnRH receptor (RGnRH) in human sperm, pituitary and cancer cells. METHODS Four oligopeptides corresponding to RGnRH amino acid residues 1-29, 182-193, 195-206 and 293-306 in the extracellular domains were synthesized, conjugated to hemocyanin from Keyhole Limpet and used as immunogens to generate specific monoclonal antibodies. Enzyme-linked immunosorbent assay was used for initial screening of hybridomas. RESULTS A total of 15 hybrid cell lines secreting RGnRH-specific monoclonal antibodies were initially established. By using some of these monoclonal antibodies as immunohistochemical probes, RGnRH was localized in the acrosomal region of human sperm, in the anterior pituitary tissue and in cancer cells of human ovarian and cervical origins. RGnRH was shown to have a molecular size of 45,000 +/- 5,000 kDa by Western blot assay. Expression of RGnRH mRNA in several human tissues and cancer cells was established by the reverse transcriptase-polymerase chain reaction method. CONCLUSION RGnRH-specific monoclonal antibodies may be a valuable tool of identifying the presence of RGnRH in various normal and malignant human tissues.
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Schwab C, DeMaggio AJ, Ghoshal N, Binder LI, Kuret J, McGeer PL. Casein kinase 1 delta is associated with pathological accumulation of tau in several neurodegenerative diseases. Neurobiol Aging 2000; 21:503-10. [PMID: 10924763 DOI: 10.1016/s0197-4580(00)00110-x] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The distribution of casein kinase 1 delta (Cki delta) was studied by immunohistochemistry and correlated with other pathological hallmarks in Alzheimer's disease (AD), Down syndrome (DS), progressive supranuclear palsy (PSP), parkinsonism dementia complex of Guam (PDC), Pick's disease (PiD), pallido-ponto-nigral degeneration (PPND), Parkinson's disease (PD), dementia with Lewy bodies (DLB), amyotrophic lateral sclerosis (ALS), and elderly controls. Cki delta was found to be associated generally with granulovacuolar bodies and tau-containing neurofibrillary tangles in AD, DS, PSP, PDC, PPND, and controls, and Pick bodies and ballooned neurons in PiD. It was not associated with tau-containing inclusions in astroglia and oligodendroglia in PPND, PSP, and PDC. It was also not associated with tau-negative Lewy bodies in PD and DLB, Hirano bodies in PDC, Marinesco bodies in PD, AD, and controls and "skein"-like inclusions in anterior motor neurons in ALS. The colocalization of the kinase Cki delta and its apparent substrate tau suggests a function for Cki delta in the abnormal processing of tau.
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Lefkowitz DL, Roberts E, Grattendick K, Schwab C, Stuart R, Lincoln J, Allen RC, Moguilevsky N, Bollen A, Lefkowitz SS. The endothelium and cytokine secretion: the role of peroxidases as immunoregulators. Cell Immunol 2000; 202:23-30. [PMID: 10873303 DOI: 10.1006/cimm.2000.1638] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The endothelium is frequently exposed to many proinflammatory mediators. The present study was done to determine the effects of human recombinant myeloperoxidase (MPO) and porcine eosinophil peroxidase (EPO) on certain endothelial cell (HUVEC) functions. The following areas were evaluated: (1) production of reactive oxygen intermediates (ROI), (2) cytokine secretion, and (3) regulation of mRNA cytokine transcripts. Both MPO and EPO induced the production of ROI, but an enzymatically inactive form of MPO (iMPO) was the most effective. Enzymatically inactive MPO, but not MPO, induced the secretion of interleukins 6 and 8 and granulocyte-monocyte colony-stimulating factor. A ribonuclease protection assay indicated that both iMPO and MPO upregulated mRNA cytokine transcripts; however, the former was markedly more effective. The simultaneous addition of EPO and iMPO resulted in a decrease in cytokine-specific mRNA. These data indicate a major role for peroxidases in the regulation of inflammation.
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Schwab C, McGeer PL. Abeta42-carboxy-terminal-like immunoreactivity is associated with intracellular neurofibrillary tangles and pick bodies. Exp Neurol 2000; 161:527-34. [PMID: 10686074 DOI: 10.1006/exnr.1999.7307] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Co-occurrence of neurofibrillary tangles (NFTs) and beta-amyloid (Abeta)-containing plaques is the pathological hallmark of Alzheimer's disease (AD). Much research has been carried out to elucidate the possible interactions of these two characteristic lesions. Here we show by immunohistochemistry that an Abeta42-carboxy-terminal-like epitope (tAbeta42) is associated with NFTs at an early, intraneuronal stage. The NFTs immunoreactive for tAbeta42 were also positive for tau2. tAbeta42 NFTs occurred even in cases without plaques or any other form of extracellular Abeta deposits. NFTs were tAbeta42 immunoreactive under all tangle forming conditions studied: AD, the parkinsonism dementia complex of Guam, progressive supranuclear palsy, and elderly controls. In Pick disease, which is another "tauopathy" Pick bodies and ballooned neurons were found to be immunoreactive for tAbeta42. Appearance of an epitope of Abeta in neurons at such an early stage of tangle formation and in Pick bodies may indicate a direct connection of Abeta42 and cytoskeletal disarrangement, although cross-reactivity with other epitopes cannot be ruled out.
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Schwab C, Dilworth K. Gas embolism produced by hydrogen peroxide abscess irrigation in an infant. Anaesth Intensive Care 1999; 27:418-20. [PMID: 10470402 DOI: 10.1177/0310057x9902700417] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The production of gaseous oxygen when hydrogen peroxide interacts with tissue is a well-known phenomenon that has been reported as a rare cause of gas embolism. We present the case of an 11-month-old infant who sustained an immediate cardiorespiratory arrest following the use of this agent during a minor surgical procedure. Clinical features, radiological findings and the rapid response to resuscitation were strongly suggestive of major gas embolism. Adverse effects of inappropriate use of hydrogen peroxide, and the diagnosis and management of these problems are discussed.
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Yasojima K, Schwab C, McGeer EG, McGeer PL. Distribution of cyclooxygenase-1 and cyclooxygenase-2 mRNAs and proteins in human brain and peripheral organs. Brain Res 1999; 830:226-36. [PMID: 10366679 DOI: 10.1016/s0006-8993(99)01389-x] [Citation(s) in RCA: 186] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
We used the techniques of reverse transcriptase-polymerase chain reaction, Western blotting and immunohistochemistry to evaluate the expression of cyclooxygenase (COX)-1 and -2 in brain and peripheral organs of Alzheimer disease (AD) and control cases. We found both COX-1 and COX-2 to be constitutively expressed in all organs tested, i.e., brain, heart, liver, kidney, spleen and intestine. COX-2 was substantially upregulated in affected areas of AD brain and in infarcted areas of human heart. COX-1 was only mildly upregulated in AD brain. Immunohistochemically, COX-2 was strongly expressed in the perinuclear, dendritic and axonal areas of pyramidal neurons, with enhanced staining in AD. These data suggest a special role for COX-2 in neuronal function.
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Abstract
Seventy-two cases of pyloric stenosis treated in our institution in the last five years were reviewed in an attempt to determine the need for postoperative analgesia after pyloromyotomy in infants. All children had their wound infiltrated with a mean dose of 2.16+/-1.43 mg x kg(-1) of bupivacaine, and first analgesia was required 9.12+/-8.04 h after surgery. Paracetamol was the main analgesic administered (average of two doses of approximately 20 mg x kg(-1)). Only three patients required postoperative opioids. In conclusion, there was a low consumption of analgesics after pyloromyotomy. Furthermore, infiltration of the wound appeared to be beneficial since time to administration of first postoperative analgesia was delayed.
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Yasojima K, Schwab C, McGeer EG, McGeer PL. Up-regulated production and activation of the complement system in Alzheimer's disease brain. THE AMERICAN JOURNAL OF PATHOLOGY 1999; 154:927-36. [PMID: 10079271 PMCID: PMC1866427 DOI: 10.1016/s0002-9440(10)65340-0] [Citation(s) in RCA: 229] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
We used reverse transcriptase-polymerase chain reaction and Western blotting techniques to measure the levels of complement mRNAs and their protein products in Alzheimer's disease (AD) brain compared with non-AD brain. mRNAs for C1q, C1r, C1s, C2, C3, C4, C5, C6, C7, C8, and C9 were detected in the 11 regions of brain that were investigated. The mRNA levels were markedly up-regulated in affected areas of AD brain. In the entorhinal cortex, hippocampus, and midtemporal gyrus, which had dense accumulations of plaques and tangles, C1q mRNA was increased 11- to 80-fold over control levels, and C9 mRNA 10- to 27-fold. These levels were substantially higher than in the livers of the same cases. Western blot analysis of AD hippocampus established the presence of all of the native complement proteins as well as their activation products C4d, C3d, and the membrane attack complex. These data indicate that high levels of complement are being produced in affected areas of AD brain, that full activation of the classical complement pathway is continuously taking place, and that this activation may be contributing significantly to AD pathology.
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