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Bozna BL, Blass J, Albrecht M, Hausen F, Wenz G, Bennewitz R. Friction mediated by redox-active supramolecular connector molecules. Langmuir 2015; 31:10708-10716. [PMID: 26367352 DOI: 10.1021/acs.langmuir.5b03026] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We report on a friction study at the nanometer scale using atomic force microscopy under electrochemical control. Friction arises from the interaction between two surfaces functionalized with cyclodextrin molecules. The interaction is mediated by connector molecules with (ferrocenylmethyl)ammonium end groups forming supramolecular complexes with the cyclodextrin molecules. With ferrocene connector molecules in solution, the friction increases by a factor of up to 12 compared to control experiments without connector molecules. The electrochemical oxidation of ferrocene to ferrocenium causes a decrease in friction owing to the lower stability of ferrocenium-cyclodextrin complex. Upon switching between oxidative and reduction potentials, a change in friction by a factor of 1.2-1.8 is observed. Isothermal titration calorimetry reveals fast dissociation and rebinding kinetics and thus an equilibrium regime for the friction experiments.
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Affiliation(s)
- B L Bozna
- INM - Leibniz-Institute for New Materials, 66123 Saarbrücken, Germany
| | - J Blass
- INM - Leibniz-Institute for New Materials, 66123 Saarbrücken, Germany
| | | | - F Hausen
- INM - Leibniz-Institute for New Materials, 66123 Saarbrücken, Germany
| | | | - R Bennewitz
- INM - Leibniz-Institute for New Materials, 66123 Saarbrücken, Germany
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2
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Blass J, Rohatgi VK. C113. Independence of certain events. J STAT COMPUT SIM 2007. [DOI: 10.1080/00949658108810520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Abstract
Haemophilus influenzae lacks most of the biosynthetic enzymes for hemin synthesis. However, the organism has retained ferrochelatase activity, which we identified to be encoded by a hemH-homologous gene. In this report we characterize the growth physiology conferred by hemH mutations under infection and laboratory conditions.
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Affiliation(s)
- S Schlör
- Zentrum für Infektionsforschung, Universität Würzburg, 97070 Würzburg, Germany
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5
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Schlör S, Riedl S, Blass J, Reidl J. Genetic rearrangements of the regions adjacent to genes encoding heat-labile enterotoxins (eltAB) of enterotoxigenic Escherichia coli strains. Appl Environ Microbiol 2000; 66:352-8. [PMID: 10618247 PMCID: PMC91829 DOI: 10.1128/aem.66.1.352-358.2000] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/1999] [Accepted: 09/28/1999] [Indexed: 02/02/2023] Open
Abstract
One of the most common bacterially mediated diarrheal infections is caused by enterotoxigenic Escherichia coli (ETEC) strains. ETEC-derived plasmids are responsible for the distribution of the genes encoding the main toxins, namely, the heat-labile and heat-stable enterotoxins. The origins and transfer modes (intra- or interplasmid) of the toxin-encoding genes have not been characterized in detail. In this study, we investigated the DNA regions located near the heat-labile enterotoxin-encoding genes (eltAB) of several clinical isolates. It was found that the eltAB region is flanked by conserved 236- and 280-bp regions, followed by highly variable DNA sequences which consist mainly of partial insertion sequence (IS) elements. Furthermore, we demonstrated that rearrangements of the eltAB region of one particular isolate, which harbors an IS91R sequence next to eltAB, could be produced by a recA-independent but IS91 sequence-dependent mechanism. Possible mechanisms of dissemination of IS element-associated enterotoxin-encoding genes are discussed.
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Affiliation(s)
- S Schlör
- Zentrum für Infektionsforschung, Universität Würzburg, 97070 Würzburg, Germany
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6
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Nesper J, Blass J, Fountoulakis M, Reidl J. Characterization of the major control region of Vibrio cholerae bacteriophage K139: immunity, exclusion, and integration. J Bacteriol 1999; 181:2902-13. [PMID: 10217785 PMCID: PMC93736 DOI: 10.1128/jb.181.9.2902-2913.1999] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/1998] [Accepted: 02/22/1999] [Indexed: 11/20/2022] Open
Abstract
The temperate bacteriophage K139 is highly associated with pathogenic O1 Vibrio cholerae strains. The nucleotide sequence of the major control region of K139 was determined. The sequences of four (cox, cII, cI, and int) of the six deduced open reading frames and their gene order indicated that K139 is related to the P2 bacteriophage family. Two genes of the lysogenic transcript from the mapped promoter PL encode homologs to the proteins CI and Int, with deduced functions in prophage formation and maintenance. Between the cI and int genes, two additional genes were identified: orf2, which has no significant similarity to any other gene, and the formerly characterized gene glo. Further analysis revealed that Orf2 is involved in preventing superinfection. In a previous report, we described that mutations in glo cause an attenuation effect in the cholera mouse model (J. Reidl and J. J. Mekalanos, Mol. Microbiol. 18:685-701, 1995). In this report, we present strong evidence that Glo participates in phage exclusion. Glo was characterized to encode a 13.6-kDa periplasmic protein which inhibits phage infection at an early step, hence preventing reinfection of vibriophage K139 into K139 lysogenic cells. Immediately downstream of gene int, the attP site was identified. Upon analysis of the corresponding attB site within the V. cholerae chromosome, it became evident that phage K139 is integrated between the flagellin genes flaA and flaC of O1 El Tor and O139 V. cholerae lysogenic strains.
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Affiliation(s)
- J Nesper
- Zentrum für Infektionsforschung, Universität Würzburg, 97070 Würzburg, Germany
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7
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Gasparini L, Racchi M, Binetti G, Trabucchi M, Solerte SB, Alkon D, Etcheberrigaray R, Gibson G, Blass J, Paoletti R, Govoni S. Peripheral markers in testing pathophysiological hypotheses and diagnosing Alzheimer's disease. FASEB J 1998; 12:17-34. [PMID: 9438407 DOI: 10.1096/fasebj.12.1.17] [Citation(s) in RCA: 110] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Alterations in amyloid precursor protein (APP) metabolism, calcium regulation, oxidative metabolism, and transduction systems have been implicated in Alzheimer's disease (AD). Limitations to the use of postmortem brain for examining molecular mechanisms underscore the need to develop a human tissue model representative of the pathophysiological processes that characterize AD. The use of peripheral tissues, particularly of cultured skin fibroblasts derived from AD patients, could complement studies of autopsy samples and provide a useful tool with which to investigate such dynamic processes as signal transduction systems, ionic homeostasis, oxidative metabolism, and APP processing. Peripheral cells as well as body fluids (i.e., plasma and CSF) could also provide peripheral biological markers for the diagnosis of AD. The criteria required for a definite diagnosis of AD presently include clinical criteria in association with histopathologic evidence obtained from biopsy or autopsy. Thus, the use of peripheral markers as a diagnostic tool, either to predict or at least to confirm a diagnosis, may be of great importance.
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Affiliation(s)
- L Gasparini
- I.R.C.C.S San Giovanni di Dio, Alzheimer's Disease Unit Sacred Heart Hospital-FBF, Brescia, Italy
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8
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Gasparini L, Racchi M, Binetti G, Trabucchi M, Solerte SB, Alkon D, Etcheberrigaray R, Gibson G, Blass J, Paoletti R, Govoni S. Peripheral markers in testing pathophysiological hypotheses and diagnosing Alzheimer's disease. FASEB J 1998. [DOI: 10.1096/fsb2fasebj.12.1.17] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- L. Gasparini
- I.R.C.C.S San Giovanni di DioAlzheimer's Disease Unit Sacred Heart Hospital‐FBFBrescia
| | - M. Racchi
- I.R.C.C.S San Giovanni di DioAlzheimer's Disease Unit Sacred Heart Hospital‐FBFBrescia
| | - G. Binetti
- I.R.C.C.S San Giovanni di DioAlzheimer's Disease Unit Sacred Heart Hospital‐FBFBrescia
| | - M. Trabucchi
- Department of Experimental Medicine and Biochemical SciencesUniversity of Roma Tor VergataUniversity of Pavia Italy
| | - S. B. Solerte
- Internal Medicine DepartmentGeriatric ClinicUniversity of Pavia Italy
| | - D. Alkon
- Laboratory of Adaptive SystemsNational Institute of Neurological Disorders and StrokeNational Institutes of Health Bethesda Maryland 20892 USA
| | - R. Etcheberrigaray
- Institute for Cognitive and Computational SciencesGeorgetown University Medical Center Washington DC 20007 USA
| | - G. Gibson
- Cornell University Medical CollegeBurke Medical Research Institute New York 10605 USA
| | - J. Blass
- Cornell University Medical CollegeBurke Medical Research Institute New York 10605 USA
| | - R. Paoletti
- Institute of Pharmacological SciencesUniversity of MilanoItaly
| | - S. Govoni
- Institute of Pharmacological SciencesUniversity of MilanoItaly
- University of PaviaItaly
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Abstract
Abnormalities in calcium regulation, amyloid-beta-protein (A beta) production and oxidative metabolism have been implicated in Alzheimer's disease (AD). The use of cultured fibroblasts complement post-mortem and genetic approaches in clarifying the interaction of these processes and the underlying mechanism for the changes in AD. Definition of gene defects in particular Alzheimer families (FAD) permits elucidation of the role of those genetic abnormalities in altered signal transduction in cell lines from those families. Abnormalities in calcium regulation, ion channels, cyclic AMP, the phosphatidylinositide cascade and oxidative metabolism are well documented in fibroblasts from patients with primary genetic defects in the presenilins. Recent studies in AD fibroblasts that demonstrate abnormal secretion of A beta, a protein known to form the characteristic extracellular amyloid deposits in AD brain, further supports the use of these cells in AD research. Comparison of changes in calcium signaling, mitochondrial oxidation and A beta production in these cells suggests that changes in signal transduction including calcium may be a more consistent observation than altered A beta production in fibroblasts from some FAD families. An understanding of these abnormalities in fibroblasts may provide further insights into the pathophysiology of AD, new diagnostic measures and perhaps innovative therapeutic approaches.
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Affiliation(s)
- G Gibson
- Cornell University Medical College, Burke Medical Research Institute, White Plains, NY 10605, USA
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Aisen ML, Sevilla D, Edelstein L, Blass J. A double-blind placebo-controlled study of 3,4-diaminopyridine in amytrophic lateral sclerosis patients on a rehabilitation unit. J Neurol Sci 1996; 138:93-6. [PMID: 8791245 DOI: 10.1016/0022-510x(96)00012-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
3,4-Diaminopyridine (DAP) enhances acetylcholine release from the nerve terminal and improves conduction in demyelinated axons. In this double-blinded placebo controlled cross over study we examined the effects of DAP combined with inpatient rehabilitation in nine patients with disabling motor weakness due to amyotrophic lateral sclerosis (ALS). A single dose of DAP or placebo was increased daily to the maximum (range: 10-80 mg) tolerated dose; after patients were assessed on the first treatment, the alternate drug was given in the same manner. Functional Independence Measurement (FIM), Ashworth, grip strength, limb strength measurements, nerve conduction studies and speech assessments were initiated 1/2 h after receiving the maximum tolerated dose of DAP or placebo. DAP was tolerated in all patients, but limited by gastrointestinal side effects in four patients. The mean peak serum level was 20.11 (S.D. = 5.11) ng/ml, occurring 1.25 (S.D. = 0.56) h after dose. A statistically significant improvement in FIM and speech assessment scores between admission and discharge occurred. However, no significant differences in clinical or electrophysiologic measures were seen between DAP and placebo treatments. This study suggests that intensive inpatient rehabilitation has a role in the management of patients with ALS, but DAP does not diminish motor impairment.
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Affiliation(s)
- M L Aisen
- Burke Rehabilitation Center, White Plains, NY 10605, USA
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11
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Abstract
The slow potassium channel blocker 3,4-diaminopyridine (DAP) enhances acetylcholine release from the nerve terminal and improves conduction in unmyelinated nerve. In this open label pilot study, we examined the effect of DAP combined with inpatient rehabilitation in seven patients with motor weakness due to amyotrophic lateral sclerosis (ALS). A single daily 20 mg oral dose of DAP was gradually increased to the maximum tolerated dose, and serum DAP concentrations were measured. Videotaped motor examination (for subsequent "blinded" review and assignment of a quantitative motor score), Functional Independence Measure (FIM) assessment, nerve conduction studies and neuropsychological evaluations were performed on admission, 1 h after maximum DAP dose, and post-treatment. DAP was tolerated in all patients, though dose was limited by gastrointestinal side effects in five patients. The mean peak serum level was 128 (+/- 50) ng/ml, occurring 1.0 (+/- 0.50) h after dose. A modest but statistically significant (p = 0.045) peak in motor score occurred on DAP. A significant (p = 0.045) improvement from baseline in FIM performance was apparent with DAP. Nerve conduction studies showed small increases in evoked response amplitudes and conduction velocities on DAP, but they did not reach statistical significance. No cognitive or affective changes were apparent. This unblinded pilot study shows that DAP is tolerated in ALS patients, and may be associated with functional and electrophysiologic improvement.
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Affiliation(s)
- M L Aisen
- Burke Rehabilitation Hospital, White Plains, NY 10605, USA
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Huang HM, Martins R, Gandy S, Etcheberrigaray R, Ito E, Alkon DL, Blass J, Gibson G. Use of cultured fibroblasts in elucidating the pathophysiology and diagnosis of Alzheimer's disease. Ann N Y Acad Sci 1994; 747:225-44. [PMID: 7847673 DOI: 10.1111/j.1749-6632.1994.tb44412.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- H M Huang
- Cornell University Medical College, Department of Neurology and Neuroscience, Burke Medical Research Institute, White Plains, New York 10605
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13
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Abstract
To test whether chromosomal instability is associated with familial Alzheimer's disease, we examined breakage on X chromosomes of fibroblasts derived from patients with familial Alzheimer's disease, using gene cotransfer methodology. The X chromosome is a convenient target for analyzing DNA breakage because of its numerous markers and ease of selection in rodent-human hybrid cells. Patients with familial Alzheimer's disease, including the large Nova Scotia Alzheimer's kindred, show a significantly lower cotransfer of the X-linked glucose-6-phosphate dehydrogenase (G6PD) gene with the selected HPRT gene in hybrid cells, indicating breakage between the markers. Lower cotransfer of the more distant X-linked gene, MIC-2, was statistically significant in this kindred, but not in other patients with familial Alzheimer's disease. The distance between MIC2 and HPRT is sixfold to ninefold greater than that between HPRT and G6PD, suggesting that there may be a "hot spot" for breakage in the latter interval on the X chromosome of patients with familial Alzheimer's disease. The somatic cell hybrid model provides insights into underlying mechanisms for chromosomal breakage induced by the Alzheimer defect. A hypothesis implicating a candidate gene, C1-THF synthase, in the generation of chromosome instability in the pathogenesis of familial Alzheimer's disease, is presented.
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Affiliation(s)
- S Ettinger
- Department of Medicine, Cornell University Medical College, New York, NY 10021
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Blass J. Convergence mechanisms in aging of the brain: A thermodynamic approach. Neurochem Int 1992. [DOI: 10.1016/0197-0186(92)90010-o] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Gibson G, Nielsen P, Mykytyn V, Carlson K, Blass J. Regionally selective alterations in enzymatic activities and metabolic fluxes during thiamin deficiency. Neurochem Res 1989; 14:17-24. [PMID: 2496326 DOI: 10.1007/bf00969752] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
To further elucidate the molecular basis of the selective damage to various brain regions by thiamin deficiency, changes in enzymatic activities were compared to carbohydrate flux through various pathways from vulnerable (mammillary bodies and inferior colliculi) and nonvulnerable (cochlear nuclei) regions after 11 or 14 days of pyrithiamin-induced thiamin deficiency. After 11 days, large decreases (-43 to -59%) in transketolase (TK) occurred in all 3 regions; 2-ketoglutarate dehydrogenase (KGDHC) declined (-45%), but only in mammillary bodies; pyruvate dehydrogenase (PDHC) was unaffected. By day 14, TK remained reduced by 58%-66%; KGDHC was now reduced in all regions (-48 to -55%); PDHC was also reduced (-32%), but only in the mammillary bodies. Thus, the enzyme changes did not parallel the pathological vulnerability of these regions to thiamin deficiency. 14CO2 production from 14C-glucose labeled in various positions was utilized to assess metabolic flux. After 14 days, CO2 production in the vulnerable regions declined severely (-46 to 70%) and approximately twice as much as those in the cochlear nucleus. Also by day 14, the ratio of enzymatic activity to metabolic flux increased as much as 56% in the vulnerable regions, but decreased 18 to 30% in the cochlear nuclei. These differences reflect a greater decrease in flux than enzyme activities in the two vulnerable regions. Thus, selective cellular responses to thiamin deficiency can be demonstrated ex vivo, and these changes can be directly related to alterations in metabolic flux. Since they cannot be related to enzymatic alterations in the three regions, factors other than decreases in the activity of these TPP-dependent enzymes must underlie selective vulnerability in this model of thiamin deficiency.
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Affiliation(s)
- G Gibson
- Cornell University Medical College, Burke Rehabilitation Center, White Plains, NY 10605
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Blass J, Detruit H, Aime L, Fiancette JY, Gaillard M, Verriest C, Vicaigne MB, Weiss M. [Protaminase activity of plasma. III. Role of conversion enzyme (kininase II) in protaminase activity of plasma]. Pathol Biol (Paris) 1988; 36:1192-8. [PMID: 2853323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Kininase I (carboxypeptidase N) and kininase II (angiotensin converting enzyme) were isolated from human plasma by gel filtration on Sephadex G 200, then separated and partially purified by ion exchange chromatography. These two partially purified enzymic preparations allowed us to demonstrate that protamine underwent an extensive degradation only when both kininases acted simultaneously. The effects of CoCl2, an activator, and of several inhibitors, amongst which captopril, suggest that the same enzymatic system is responsible for the in vitro protaminasic activity of diluted unfractionated plasma.
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Affiliation(s)
- J Blass
- Hôpital Marie Lannelongue, Le Plessis-Robinson, France
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Weiss M, Blass J, Detruit H, Aime L, Baudet B, Fiancette JY, Gaillard M, Vicaigne MB, Verriest C. Determination of "in vitro" degradation of protamine in plasma by three different methods. Thromb Res 1986; 41:593-604. [PMID: 3961737 DOI: 10.1016/0049-3848(86)90356-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Three techniques for the quantitative or semi-quantitative determination of the degradation of protamine in plasma are described. One is based on the measurement of liberated arginine, since arginine is the single most important constituent of protamine (80% in weight). The second utilizes successive estimations of protamine by addition to a secondary heparinized medium in which excess heparin is measured by thrombin time and polybrene titration. The third method employs electrophoresis on cellulose acetate, and offers direct visualization of the soluble complexes formed between protamine and albumin, and of their degradation. When applied to an incubation mixture containing diluted plasma (1 : 8) and protamine 0.8 mg/ml, the first two methods were well correlated and showed that protamine degradation proceeded linearly with time. The third method had good semiquantitative agreement with the two former. The rate of protamine degradation was different when estimated by each of the three methods, due probably to the different physico-chemical reactions involved.
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Abstract
Of 225 patients referred to a dementia clinic, depression occurred in 31 (70%) of 44 patients not thought to be demented, six (24%) of 25 with cognitive impairment not severe enough to warrant the label dementia, and 24 (15%) of 156 with various forms of dementia, including 19 (19%) of 99 with Alzheimer-type dementia. Follow-up over three years has shown that 16 (57%) of 28 of the depressed, nondemented patients went on to develop frank dementia. Thirteen of these 16 had some sign, often subtle, of organic neurologic disease. Depressed elderly patients with any of the following are at high risk to develop dementia: evidence of cerebrovascular, extrapyramidal, or spinocerebellar disease; a modified Hachinski ischemic score of 4 or greater; a Mental Status Questionnaire score under 8; a dementia behavior score of 7 or higher; or confusion on low doses of tricyclic antidepressants. Dementing illnesses can present as depression with relatively little cognitive impairment.
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Burstein S, Schaff-Blass E, Blass J, Rosenfield RL. The changing ratio of bioactive to immunoreactive luteinizing hormone (LH) through puberty principally reflects changing LH radioimmunoassay dose-response characteristics. J Clin Endocrinol Metab 1985; 61:508-13. [PMID: 3894406 DOI: 10.1210/jcem-61-3-508] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The ratio (B/I) of bioactive to immunoreactive LH in plasma varies during pubertal maturation. To elucidate the basis for these changes, we compared the dose-response characteristics of LH standards to those of plasma LH before and after GnRH infusion in normal males at various pubertal stages and girls with Turner's syndrome. We used a human LH (hLH) RIA modified to optimize specificity for LH bioactivity by employing a hLH tracer maximally bioactive in the rat interstitial cell testosterone production (RICT) bioassay. The pituitary hLH standards LER-907, NHPP I-1, and NHPP I-2 were not parallel to one another in the RIA, but were parallel in the RICT. Their relative slopes in the RIA were 1:1.35:1.49, respectively. The B/I for immunoreactive LH in these standards were 1 (LER-907):3 (I-1):5 (I-2). Dose-response characteristics varied greatly by patient category in the RIA. In contrast to the RICT, in which plasma from all subject groups, except the prepubertal basal group, gave parallel dose-response slopes, the groups differed in the steepness of their plasma LH RIA dose-response curves in the following order: adult post-GnRH congruent to adult basal congruent to pubertal post-GnRH greater than pubertal basal congruent to prepubertal post-GnRH congruent to prepubertal basal greater than Turner's syndrome. Prepubertal basal samples most closely resembled LER-907 in dose-response characteristics, while adult samples were most similar to NHPP I-1 and I-2. These characteristics were not related to the absolute LH concentration. Although the RIA dose-response characteristics of plasma LH changed during puberty, the B/I of basal LH did not increase through puberty using the modified hLH RIA, although B/I still rose in GnRH-stimulated samples during puberty. Our data demonstrate that the principal cause of variability in B/I is the changing dose-response characteristics of plasma LH in the RIA. We suggest that the source of this variability is a change in the molecular characteristics of LH in different states of pubertal maturation and gonadal function. The results imply that better ways of assaying LH are needed.
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Horoupian DS, Thal L, Katzman R, Terry RD, Davies P, Hirano A, DeTeresa R, Fuld PA, Petito C, Blass J. Dementia and motor neuron disease: morphometric, biochemical, and Golgi studies. Ann Neurol 1984; 16:305-13. [PMID: 6148912 DOI: 10.1002/ana.410160306] [Citation(s) in RCA: 86] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
In three patients dementia without neurofibrillary tangles or Pick bodies antedated amyotrophy by several years. The motor neuron disorder in two patients was characterized by terminal bulbar symptoms; in one it was similar to classic amyotrophic lateral sclerosis. In two patients, quantitative studies of selected regions of the cortex using a computerized image analyzer disclosed, as in patients with senile dementia of Alzheimer type, a marked reduction in the number of neurons, especially those larger than 90 mu 2. The findings differed from those in Alzheimer dementia, however, in that the cells in the substantia innominata were not reduced and the levels of choline acetyltransferase and somatostatin-like immunoreactivity, determined in one patient, were within normal limits. A variable degree of sponginess of the upper layers of the cortex was attributed to attrition of pyramidal cell dendrites, observed in the one patient in whom Golgi study was successful. Because of severe degeneration of the substantia nigra in all three, the disease in these patients may represent a subset of motor neuron disease or a multisystem atrophy.
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Blass J, Verriest C, Vicaigne MB, Detruit H, Weiss M. [Protaminase activity of plasma and serum in vitro. II.- Electrophoretic study of serum albumin-protamine soluble complexes]. Pathol Biol (Paris) 1984; 32:40-4. [PMID: 6701006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Cellulose acetate electrophoresis (pH 8,6 ionic strength 0,05) puts in evidence the soluble complexes "albumin-protamine" which are easily distinguished from albumin being more positively charged. The albumin-protamine complexes formed in serum or plasma, after addition of protamine, undergo in vitro a dissociation progressing with time to the complete restitution of albumin. This dissociation is slowed down by the inhibitors of the carboxypeptidase B (SCPB), an enzyme present in plasma and serum, but is not influenced by the inhibitor phenylmethyl-sulfonyl fluoride (PMSF). A protamine which had lost its four C-terminal arginines by the action of a DFP-treated carboxypeptidase B (CPB) still formed complexes with albumin (and, besides, remained able to neutralize heparin). On the contrary protamine degraded first by CPB, and afterwards by the DFP-treated carboxypeptidase A (CPA) lost these two properties. These results suggest that the dissociation of albumin-protamine complex in plasma and serum requires a protaminase action additional to the action of SCPB.
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Blass J, Verriest C, Vicaigne MB, Weiss M. ["In vitro" protaminase activity of human plasma and serum and the human carboxypeptidase N (author's transl)]. Pathol Biol (Paris) 1980; 28:527-34. [PMID: 6448971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
1 - Protamine was incubated "in vitro", with human plasma and serum, and the initial degradation products (1-4 hours at 30 degrees C) were characterized by paper chromatographic and paper electrophoretic methods. The analysis revealed the presence of the arginine and also, in low quantities, that of a supplementary compound, an arginine peptide. Comparative experiences with the same substrate revealed that carboxypeptidase B liberated exclusively the C-terminal arginine, plasmin exclusively peptides of arginine, and trypsin, besides arginine peptides, minutes quantities of free arginine. 2 - The method used for quantitative determination of arginine liberated by the action of plasma and serum is based on coprecipitation of residual and partly degradated protamine with the plasma proteins by addition of methanol-acetone. The arginine recovered from supernatant is determined with the Sakagushi reagent. 3 - We could thus demonstrate that the protaminase activity of human plasma and serum in greatly enhanced by cobalt and is inhibited by cadmium and EDTA. Trypsin inhibitor of Künitz and PMSF have little effect. These characters are those of the human carboxypeptidase N of Erdös and al. 4 - The comparison of protamines from different laboratories did not reveal essential differences between protamine sulfate and protamine chloride as some authors have claimed. 5 - The results of this investigation suggest that the "in vitro" enzymatic action of human plasma and serum on protamine is mostly due, at least during the first hours of incubation, to the carboxypeptidase N, described by Erdös and al. A low enzymatic additional action on protamine was observed. This action of proteasic character was not inhibited by the trypsin inhibitor of Künitz.
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Blass J. Food selection in the aged. Int J Obes (Lond) 1980; 4:377-80. [PMID: 7419356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Old people's eating habits are often idiosyncratic and unhealthy; their feeding can reflect such brain disease are dementia, depression, paranoia; poor nutrition can contribute to degenerative brain disease. The modification of nutritional requirements of the aged by genetic factors is discussed.
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Detruit H, Blass J, Weiss M. Antigenic similarities between human plasma inhibitor of thrombin (At-III) and its analogues from other mammals. Biomedicine 1979; 31:176-8. [PMID: 93495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cross reactions investigated by double immunodiffusion and by immunoelectrophoresis between human plasma and plasma of 5 animal species using a specific rabbit antiserum against human At-III revealed antigenic relationships between the antithrombins of these species. But the quantitative measurements of At-III by immunologic methods (electro-immunodiffusion and radial immunodiffusion), using the rabbit antiserum, were not possible in common laboratory animals, except in baboons.
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Weiss M, Blass J, Leau A, Verriest C. Heparin cofactor activity during and after extracorporeal circulation with bubble and membrane oxygenators. Biomedicine 1977; 27:248-9. [PMID: 73390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Heparin cofactor activity as measured by an amidolytic method has been investigated in 48 patients undergoing cardiac surgery with extra-corporeal circulation (E.C.C.). Heparin cofactor activity is reduced soon after the start of E.C.C., due to hemodilution but it returns towards initial levels at the completion of the procedure and 3 hours later. Thus heparin cofactor does not seem to play a role in the heparin rebound phenomenon. In our patients bubble oxygenators did not modify heparin cofactor activity more than did membrane oxygenators.
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Abstract
In patients with partial deficiencies of pyruvate dehydrogenase, cerebellar ataxia has been the most prominent and sometimes the only neurologic abnormality. It is not clear how this generalized enzyme deficiency (with activity 15 to 30 percent of normal in several tissues) might lead to clinical signs referable to a limited part of the nervous system. We therefore compared the normal activity of pyruvate dehydrogenase with the normal rate of pyruvate oxidation in different parts of animal brains and then calculated the effect on pyruvate oxidation of partial deficiencies of the enzyme. The data indicate that pyruvate oxidation could be impaired in an area of anterior cerebellar vermis by deficiencies of pyruvate dehydrogenase too mild to affect pyruvate oxidation in the other areas of the brain we examined.
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Blass J, Verriest C, Leau A, Detruit H, Weiss M. [Comparative study of fixation on heterografts of several aldehydes used for their tanning. Application of the Sawicki-Paz aldehyde assay method]. Pathol Biol (Paris) 1974; 22:593-601. [PMID: 4612463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Pardun H, Blass J, Kroll E. Veränderungen der Fette unter Fritierbedingungen und deren analytische Erfassung Beurteilung des Gebrauchswertes und Analytik von Fritierfetten I. ACTA ACUST UNITED AC 1974. [DOI: 10.1002/lipi.19740760302] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Pardun H, Blass J, Kroll E. Veränderungen der Fette unter Fritierbedingungen und deren analytische Erfassung Beurteilung des Gebrauchswertes und Analytik von Fritierfetten II. ACTA ACUST UNITED AC 1974. [DOI: 10.1002/lipi.19740760403] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Lecroisey A, Bizzini B, Blass J, Raynaud M. [Relations between the structure of diphtheric toxin and anatoxin]. C R Acad Hebd Seances Acad Sci D 1972; 274:2395-7. [PMID: 4114147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Bizzini B, Blass J, Turpin A, Raynaud M. Chemical characterization of tetanus toxin and toxoid. Amino acid composition, number of SH and S-S groups and N-terminal amino acid. Eur J Biochem 1970; 17:100-5. [PMID: 5486573 DOI: 10.1111/j.1432-1033.1970.tb01141.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Nauciel C, Blass J, Mangalo R, Raynaud M. Evidence for two molecular forms of streptococcal erythrogenic toxin. Conversion to a single form by 2-mercaptoethanol. Eur J Biochem 1969; 11:160-4. [PMID: 4982089 DOI: 10.1111/j.1432-1033.1969.tb00754.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Blass J, Bizzini B, Raynaud M. [Study on the mechanism of protein toxin detoxification by formol. II. Quantitative fixation of C14 formol]. Ann Inst Pasteur (Paris) 1969; 116:501-21. [PMID: 5366476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Blass J, Bizzini B, Raynaud M. [Study on the mechanism of detoxification of protein toxins by formol. I. Incorporation of free radioactive lysine in pure diphtheria toxin in the presence of formol (irreversible detoxification)]. Ann Inst Pasteur (Paris) 1968; 115:881-98. [PMID: 5750250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Blass J, Bizzini B, Raynaud M. [Mechanism of detoxification by formol]. C R Acad Hebd Seances Acad Sci D 1965; 261:1448-9. [PMID: 4954193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Blass J, Sarraff A, Nicolas MB. Analyse des amines biologiques par les techniques de chromatoïonophorèse, électrophorèse et chromatographie sur papier. J Chromatogr A 1960. [DOI: 10.1016/s0021-9673(01)96973-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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