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Kotler M, Cohen H, Segman R, Gritsenko I, Nemanov L, Lerer B, Kramer I, Zer-Zion M, Kletz I, Ebstein RP. Excess dopamine D4 receptor (D4DR) exon III seven repeat allele in opioid-dependent subjects. Mol Psychiatry 1997; 2:251-4. [PMID: 9152990 DOI: 10.1038/sj.mp.4000248] [Citation(s) in RCA: 148] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Only in the past decade has a role of heredity in substance abuse been established as a result of extensive twin and family studies. More recently, several candidate genes have been investigated for their possible role in alcoholism and cocaine abuse. Specific genetic factors in opioid substance abuse have not been investigated in man, although animal studies suggest that quantitative trait loci (QTLs) can be identified that predispose mice both to morphine and alcohol preference. Central dopaminergic pathways figure prominently in drug-mediated reinforcement suggesting that dopamine receptors are likely candiadates for association with substance abuse in man. In addition, we recently reported an association between a human personality trait, Novelty Seeking and the long alleles (represented chiefly by the 7-repeat) of the D4 dopamine receptor (D4DR) exon III polymorphism. The personality trait of Novelty Seeking is also more pronounced in substance abusers, who score higher in this dimension than control subjects. The twin role of dopamine receptors in mediating Novelty Seeking and drugreinforcement prompted us to examine a group of Israeli heroin addicts for prevalence of the D4DR repeat polymorphism. We now show that the 7-repeat allele is significantly over-represented in the opioid-dependent cohort and confers a relative risk of 2.46. To our knowledge this is the first report of an association between a specific genetic polymorphism and opioid addiction.
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Stackebrandt E, Kramer I, Swiderski J, Hippe H. Phylogenetic basis for a taxonomic dissection of the genus Clostridium. FEMS IMMUNOLOGY AND MEDICAL MICROBIOLOGY 1999; 24:253-8. [PMID: 10397308 DOI: 10.1111/j.1574-695x.1999.tb01291.x] [Citation(s) in RCA: 116] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The 16S rDNA-based phylogenetic analysis of the genus Clostridium has been completed by determination of the phylogenetic position of the type strains of 15 species and two non-validated species. These strains are members of phylogenetic clusters I, III, IV, V, IX, XIVa and XVIII as defined previously by Collins et al. [Int. J. Syst. Bacteriol. 44 (1994) 812-826]. Members of the genus Clostridium span a large evolutionary distance and the genus is not a phylogenetically coherent taxon but is intermixed with members of different genera, exhibiting a combination of Clostridium- and non-Clostridium-type properties. Anaerobacter polyendosporus, Syntrophococcus sucromutans and Acetivibrio multivorans also cluster within the radiation of Clostridium species. Although several taxa have been described for former Clostridium species with distinct phenotypic properties, the majority of Clostridium species, which are not members of the core cluster I, can at present not be reclassified as long as taxon-specific, phenotypic properties are not available.
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Heuer H, Hartung K, Wieland G, Kramer I, Smalla K. Polynucleotide probes that target a hypervariable region of 16S rRNA genes to identify bacterial isolates corresponding to bands of community fingerprints. Appl Environ Microbiol 1999; 65:1045-9. [PMID: 10049861 PMCID: PMC91142 DOI: 10.1128/aem.65.3.1045-1049.1999] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/1998] [Accepted: 12/08/1998] [Indexed: 11/20/2022] Open
Abstract
Temperature gradient gel electrophoresis (TGGE) is well suited for fingerprinting bacterial communities by separating PCR-amplified fragments of 16S rRNA genes (16S ribosomal DNA [rDNA]). A strategy was developed and was generally applicable for linking 16S rDNA from community fingerprints to pure culture isolates from the same habitat. For this, digoxigenin-labeled polynucleotide probes were generated by PCR, using bands excised from TGGE community fingerprints as a template, and applied in hybridizations with dot blotted 16S rDNA amplified from bacterial isolates. Within 16S rDNA, the hypervariable V6 region, corresponding to positions 984 to 1047 (Escherichia coli 16S rDNA sequence), which is a subset of the region used for TGGE (positions 968 to 1401), best met the criteria of high phylogenetic variability, required for sufficient probe specificity, and closely flanking conserved priming sites for amplification. Removal of flanking conserved bases was necessary to enable the differentiation of closely related species. This was achieved by 5' exonuclease digestion, terminated by phosphorothioate bonds which were synthesized into the primers. The remaining complementary strand was removed by single-strand-specific digestion. Standard hybridization with truncated probes allowed differentiation of bacteria which differed by only two bases within the probe target site and 1.2% within the complete 16S rDNA. However, a truncated probe, derived from an excised TGGE band of a rhizosphere community, hybridized with three phylogenetically related isolates with identical V6 sequences. Only one of the isolates comigrated with the excised band in TGGE, which was shown to be due to identical sequences, demonstrating the utility of a combined TGGE and V6 probe approach.
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Morse A, McDonald MM, Kelly NH, Melville KM, Schindeler A, Kramer I, Kneissel M, van der Meulen MCH, Little DG. Mechanical load increases in bone formation via a sclerostin-independent pathway. J Bone Miner Res 2014; 29:2456-67. [PMID: 24821585 PMCID: PMC4501925 DOI: 10.1002/jbmr.2278] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2014] [Revised: 04/22/2014] [Accepted: 05/06/2014] [Indexed: 01/24/2023]
Abstract
Sclerostin, encoded by the Sost gene, is an important negative regulator of bone formation that has been proposed to have a key role in regulating the response to mechanical loading. To investigate the effect of long-term Sclerostin deficiency on mechanotransduction in bone, we performed experiments on unloaded or loaded tibiae of 10 week old female Sost-/- and wild type mice. Unloading was induced via 0.5U botulinum toxin (BTX) injections into the right quadriceps and calf muscles, causing muscle paralysis and limb disuse. On a separate group of mice, increased loading was performed on the left tibiae through unilateral cyclic axial compression of equivalent strains (+1200 µe) at 1200 cycles/day, 5 days/week. Another cohort of mice receiving equivalent loads (-9.0 N) also were assessed. Contralateral tibiae served as normal load controls. Loaded/unloaded and normal load tibiae were assessed at day 14 for bone volume (BV) and formation changes. Loss of BV was seen in the unloaded tibiae of wild type mice, but BV was not different between normal load and unloaded Sost-/- tibiae. An increase in BV was seen in the loaded tibiae of wild type and Sost-/- mice over their normal load controls. The increased BV was associated with significantly increased mid-shaft periosteal mineralizing surface/bone surface (MS/BS), mineral apposition rate (MAR), and bone formation rate/bone surface (BFR/BS), and endosteal MAR and BFR/BS. Notably, loading induced a greater increase in periosteal MAR and BFR/BS in Sost-/- mice than in wild type controls. Thus, long-term Sclerostin deficiency inhibits the bone loss normally induced with decreased mechanical load, but it can augment the increase in bone formation with increased load.
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Research Support, N.I.H., Extramural |
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Groth I, Schumann P, Schuetze B, Augsten K, Kramer I, Stackebrandt E. Beutenbergia cavernae gen. nov., sp. nov., an L-lysine-containing actinomycete isolated from a cave. INTERNATIONAL JOURNAL OF SYSTEMATIC BACTERIOLOGY 1999; 49 Pt 4:1733-40. [PMID: 10555355 DOI: 10.1099/00207713-49-4-1733] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Two aerobic, Gram-positive bacteria, strains HKI 0122T and HKI 0132, were isolated from a cave. Cells are not acid-fast, non-motile, non-spore-forming and exhibit a rod-coccus growth cycle. The cell wall peptidoglycan contains lysine in position 3 of the peptide subunit and an interpeptide bridge of L-Lys<--L-Glu. The major menaquinone is MK-8(H4), 13-methyl and 12-methyl tetradecanoic acids are the predominating fatty acids. The polar lipids consist of phosphatidylinositol, diphosphatidylglycerol and three unknown phospholipids. Mycolic acids are absent. The DNA base composition is 71 mol% G + C. Phylogenetic analysis revealed that strain HKI 0122T forms a novel taxon among the families and unassigned genera of the suborder Micrococcineae, within the order Actinomycetales. On the basis of the genotypic, chemotaxonomic, morphological and physiological characteristics of these two isolates it is proposed to assign strains HKI 0122T and HKI 0132 to a new genus and species for which the name Beutenbergia cavernae gen. nov., sp. nov. is proposed. The type strain is HKI 0122T (= DSM 12333T).
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Groth I, Schumann P, Martin K, Schuetze B, Augsten K, Kramer I, Stackebrandt E. Ornithinicoccus hortensis gen. nov., sp. nov., a soil actinomycete which contains L-ornithine. INTERNATIONAL JOURNAL OF SYSTEMATIC BACTERIOLOGY 1999; 49 Pt 4:1717-24. [PMID: 10555353 DOI: 10.1099/00207713-49-4-1717] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Two Gram-positive coccoid, non-motile bacteria with L-ornithine as diagnostic diamino acid of the peptidoglycan and an interpeptide bridge of L-Orn<--Gly(1,2)<--D-Glu were isolated from a sample of garden soil. The major menaquinone is MK-8(H4). 13-methyl and 12-methyl tetradecanoic acids are the predominant fatty acids. The polar lipids are phosphatidylinositol, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylserine and two unknown phospholipids. Mycolic acids are absent. The DNA base composition is 72 mol% G + C. Recent comparative 16S rDNA studies revealed that strains HKI 0125T and HKI 0131 represent a novel lineage adjacent to the family Intrasporangiaceae of the order Actinomycetales but distinct from the previously described genera of this family. On the basis of the genotypic, chemotaxonomic, morphological and physiological characteristics of these two isolates it is proposed to classify HKI 0125T and HKI 0131 in a new genus and species for which the name Ornithinicoccus hortensis gen. nov., sp. nov. is proposed. The type strain is HKI 0125T (= DSM 12335T).
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Hippe H, Hagelstein A, Kramer I, Swiderski J, Stackebrandt E. Phylogenetic analysis of Formivibrio citricus, Propionivibrio dicarboxylicus, Anaerobiospirillum thomasii, Succinimonas amylolytica and Succinivibrio dextrinosolvens and proposal of Succinivibrionaceae fam. nov. INTERNATIONAL JOURNAL OF SYSTEMATIC BACTERIOLOGY 1999; 49 Pt 2:779-82. [PMID: 10319502 DOI: 10.1099/00207713-49-2-779] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The phylogenetic position of Gram-negative, strictly anaerobic, non-spore-forming bacteria, representing four different genera, was determined by analysis of their 16S rDNA sequences. Formivibrio citricus and Propionivibrio dicarboxylicus are members of the beta-subclass of the class Proteobacteria. While Formivibrio citricus stands phylogenetically isolated, Propionivibrio dicarboxylicus is moderately related to members of the genus Rhodocyclus. Succinimonas amylolytica and Succinivibrio dextrinosolvens are members of the gamma-subclass of the class Proteobacteria in which they, together with members of the genus Anaerobiospirillum and Ruminobacter amylophilus, form a separate line of descent. This phylogenetic group is described as Succinivibrionaceae fam. nov.
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Rosenstein BJ, Markowitz M, Goldstein E, Kramer I, O'Mansky B, Seidel H, Sigler A, Tramer A. Factors involved in treatment failures following oral penicillin therapy of streptococcal pharyngitis. J Pediatr 1968; 73:513-20. [PMID: 4971165 DOI: 10.1016/s0022-3476(68)80266-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Croft D, McIntyre P, Wibulswas A, Kramer I. Sustained elevated levels of VCAM-1 in cultured fibroblast-like synoviocytes can be achieved by TNF-alpha in combination with either IL-4 or IL-13 through increased mRNA stability. THE AMERICAN JOURNAL OF PATHOLOGY 1999; 154:1149-58. [PMID: 10233853 PMCID: PMC1866562 DOI: 10.1016/s0002-9440(10)65367-9] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Rheumatoid arthritis is characterized by hyperplasia of the synovial lining and invasion of cartilage and bone by a subset of resident synovial cells named fibroblast-like synoviocytes. They are characterized by elevated expression of the vascular cell adhesion molecule-1 (VCAM-1). The intensity of VCAM-1 expression correlates with the degree of inflammation of the synovial joint. Differential VCAM-1 expression may determine inflammatory cell accumulation through its interaction with leukocytes that express the counterreceptor integrins alpha4beta1 and alpha4beta7. Elevated levels of VCAM-1 expression are thought to be a consequence of the presence of inflammatory mediators, in particular IL-1beta and TNF-alpha. Fibroblast-like synoviocytes rapidly up-regulate VCAM-1 expression in response to IL-1beta and TNF-alpha, but also to IL-4. However, we now show that the response to IL-1beta or TNF-alpha is of a brief transient nature, even when applied continuously over a period of 12 days, whereas the response to IL-4 or IL-13 is sustained. Great synergy is obtained by combining either IL-4 or IL-13 with TNF-alpha, which results in a highly elevated but also sustained expression of VCAM-1. The mechanism by which IL-4 or IL-13 prolongs VCAM-1 expression can be explained by a dramatic increase in the half-life of VCAM-1 mRNA.
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Stadlinger B, Korn P, Tödtmann N, Eckelt U, Range U, Bürki A, Ferguson SJ, Kramer I, Kautz A, Schnabelrauch M, Kneissel M, Schlottig F. Osseointegration of biochemically modified implants in an osteoporosis rodent model. Eur Cell Mater 2013; 25:326-40; discussion 339-40. [PMID: 23832686 DOI: 10.22203/ecm.v025a23] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The present study examined the impact of implant surface modifications on osseointegration in an osteoporotic rodent model. Sandblasted, acid-etched titanium implants were either used directly (control) or were further modified by surface conditioning with NaOH or by coating with one of the following active agents: collagen/chondroitin sulphate, simvastatin, or zoledronic acid. Control and modified implants were inserted into the proximal tibia of aged ovariectomised (OVX) osteoporotic rats (n = 32/group). In addition, aged oestrogen competent animals received either control or NaOH conditioned implants. Animals were sacrificed 2 and 4 weeks post-implantation. The excised tibiae were utilised for biomechanical and morphometric readouts (n = 8/group/readout). Biomechanical testing revealed at both time points dramatically reduced osseointegration in the tibia of oestrogen deprived osteoporotic animals compared to intact controls irrespective of NaOH exposure. Consistently, histomorphometric and microCT analyses demonstrated diminished bone-implant contact (BIC), peri-implant bone area (BA), bone volume/tissue volume (BV/TV) and bone-mineral density (BMD) in OVX animals. Surface coating with collagen/chondroitin sulphate had no detectable impact on osseointegration. Interestingly, statin coating resulted in a transient increase in BIC 2 weeks post-implantation; which, however, did not correspond to improvement of biomechanical readouts. Local exposure to zoledronic acid increased BIC, BA, BV/TV and BMD at 4 weeks. Yet this translated only into a non-significant improvement of biomechanical properties. In conclusion, this study presents a rodent model mimicking severely osteoporotic bone. Contrary to the other bioactive agents, locally released zoledronic acid had a positive impact on osseointegration albeit to a lesser extent than reported in less challenging models.
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Genot E, Reif K, Beach S, Kramer I, Cantrell D. p21ras initiates Rac-1 but not phosphatidyl inositol 3 kinase/PKB, mediated signaling pathways in T lymphocytes. Oncogene 1998; 17:1731-8. [PMID: 9796702 DOI: 10.1038/sj.onc.1202101] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
p21ras is activated by the T cell antigen receptor (TCR) and then co-ordinates important signaling pathways for T lymphocyte activation. Effector pathways for this guanine nucleotide binding protein in T cells are mediated by the serine/threonine kinase Raf-1 and the Ras-related GTPase Rac-1. In fibroblasts, an important effector for the Ras oncogene is Phosphatidylinositol 3-kinase (PtdIns 3-kinase). Activation of this lipid kinase is able to induce critical Rac-1 signaling pathways and can couple p21ras to cell survival mechanisms via the serine/threonine kinase Akt/PKB. The role of PtdIns 3-kinase in Ras signaling in T cells has not been explored. In the present study, we examined the ability of PtdIns 3-kinase to initiate the Rac-1 signaling pathways important for T cell activation. We also examined the possibility that Akt/PKB is regulated by Ras signaling pathways in T lymphocytes. The results show that Ras can initiate a Rac-1 mediated pathway that regulates the transcriptional function of AP-1 complexes. PtdIns 3-kinase signals cannot mimic p21ras and induce the Rac mediated responses of AP-1 transcriptional activation. Moreover, neither TCR or Ras activation of AP-1 is dependent on PtdIns 3-kinase. PKB is activated in response to triggering of the T cell antigen receptor; PtdIns 3-kinase activity is both required and sufficient for this TCR response. In contrast, p21ras signals are unable to induce Akt/PKB activity in T cell nor is Ras function required for Akt/PKB activation in response to the TCR. The present data thus highlight that PtdIns 3-kinase and Akt/PKB are not universal Ras effector molecules. Ras can initiate Rac-1 regulated signaling pathways in the context of T cell antigen receptor function independently of PtdIns 3-kinase activity.
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Van Lier RA, Brouwer M, De Groot ED, Kramer I, Aarden LA, Verhoeven AJ. T cell receptor/CD3 and CD28 use distinct intracellular signaling pathways. Eur J Immunol 1991; 21:1775-8. [PMID: 1647959 DOI: 10.1002/eji.1830210731] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Ligation of the T cell membrane antigen CD28 strongly enhances cytokine secretion in human T lymphocytes that are activated via T cell receptor (TcR)/CD3 or CD2 molecules. This study was undertaken to investigate whether, as has been indicated for activation via TcR/CD3, stimulation via CD28 is dependent on the activation of protein kinase C (PKC). Two inhibitors of PKC, 1-alkyl 2-methyl-glycerol and staurosporine, caused a dose-dependent inhibition of T cell proliferation induced by anti-CD3 monoclonal antibodies (mAb). The induction of interleukin (IL) 2 secretion was found to be more sensitive to the effects of the PKC inhibitors than the up-regulation of IL 2 receptor expression. In marked contrast, the anti-CD28 mAb-mediated enhancement of T cell proliferation and IL 2 secretion were insensitive to the action of either compound. We conclude that two independent signaling pathways may be operational in human T cells. The first used by TcR/CD3 depends on the activation of PKC, whereas the second is employed by CD28 and functions independently of PKC.
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Morse A, Yu NYC, Peacock L, Mikulec K, Kramer I, Kneissel M, McDonald MM, Little DG. Endochondral fracture healing with external fixation in the Sost knockout mouse results in earlier fibrocartilage callus removal and increased bone volume fraction and strength. Bone 2015; 71:155-63. [PMID: 25445453 DOI: 10.1016/j.bone.2014.10.018] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 09/24/2014] [Accepted: 10/24/2014] [Indexed: 12/11/2022]
Abstract
Sclerostin deficiency, via genetic knockout or anti-Sclerostin antibody treatment, has been shown to cause increased bone volume, density and strength of calluses following endochondral bone healing. However, there is limited data on the effect of Sclerostin deficiency on the formative early stage of fibrocartilage (non-bony tissue) formation and removal. In this study we extensively investigate the early fibrocartilage callus. Closed tibial fractures were performed on Sost(-/-) mice and age-matched wild type (C57Bl/6J) controls and assessed at multiple early time points (7, 10 and 14days), as well as at 28days post-fracture after bony union. External fixation was utilized, avoiding internal pinning and minimizing differences in stability stiffness, a variable that has confounded previous research in this area. Normal endochondral ossification progressed in wild type and Sost(-/-) mice with equivalent volumes of fibrocartilage formed at early day 7 and day 10 time points, and bony union in both genotypes by day 28. There were no significant differences in rate of bony union; however there were significant increases in fibrocartilage removal from the Sost(-/-) fracture calluses at day 14 suggesting earlier progression of endochondral healing. Earlier bone formation was seen in Sost(-/-) calluses over wild type with greater bone volume at day 10 (221%, p<0.01). The resultant Sost(-/-) united bony calluses at day 28 had increased bone volume fraction compared to wild type calluses (24%, p<0.05), and the strength of the fractured Sost(-/-) tibiae was greater than that that of wild type fractured tibiae. In summary, bony union was not altered by Sclerostin deficiency in externally-fixed closed tibial fractures, but fibrocartilage removal was enhanced and the resultant united bony calluses had increased bone fraction and increased strength.
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Dorhout Mees SM, Algra A, Wong GKC, Poon WS, Bradford CM, Saver JL, Starkman S, Rinkel GJE, van den Bergh WM, van Kooten F, Dirven CM, van Gijn J, Vermeulen M, Rinkel GJE, Boet R, Chan MTV, Gin T, Ng SCP, Zee BCY, Al-Shahi Salman R, Boiten J, Kuijsten H, Lavados PM, van Oostenbrugge RJ, Vandertop WP, Finfer S, O'Connor A, Yarad E, Firth R, McCallister R, Harrington T, Steinfort B, Faulder K, Assaad N, Morgan M, Starkman S, Eckstein M, Stratton SJ, Pratt FD, Hamilton S, Conwit R, Liebeskind DS, Sung G, Kramer I, Moreau G, Goldweber R, Sanossian N. Early Magnesium Treatment After Aneurysmal Subarachnoid Hemorrhage: Individual Patient Data Meta-Analysis. Stroke 2015; 46:3190-3. [PMID: 26463689 DOI: 10.1161/strokeaha.115.010575] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 09/08/2015] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Delayed cerebral ischemia (DCI) is an important cause of poor outcome after aneurysmal subarachnoid hemorrhage (SAH). Trials of magnesium treatment starting <4 days after symptom onset found no effect on poor outcome or DCI in SAH. Earlier installment of treatment might be more effective, but individual trials had not enough power for such a subanalysis. We performed an individual patient data meta-analysis to study whether magnesium is effective when given within different time frames within 24 hours after the SAH. METHODS Patients were divided into categories according to the delay between symptom onset and start of the study medication: <6, 6 to 12, 12 to 24, and >24 hours. We calculated adjusted risk ratios with corresponding 95% confidence intervals for magnesium versus placebo treatment for poor outcome and DCI. RESULTS We included 5 trials totaling 1981 patients; 83 patients started treatment<6 hours. For poor outcome, the adjusted risk ratios of magnesium treatment for start <6 hours were 1.44 (95% confidence interval, 0.83-2.51); for 6 to 12 hours 1.03 (0.65-1.63), for 12 to 24 hours 0.84 (0.65-1.09), and for >24 hours 1.06 (0.87-1.31), and for DCI, <6 hours 1.76 (0.68-4.58), for 6 to 12 hours 2.09 (0.99-4.39), for 12 to 24 hours 0.80 (0.56-1.16), and for >24 hours 1.08 (0.88-1.32). CONCLUSIONS This meta-analysis suggests no beneficial effect of magnesium treatment on poor outcome or DCI when started early after SAH onset. Although the number of patients was small and a beneficial effect cannot be definitively excluded, we found no justification for a new trial with early magnesium treatment after SAH.
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Research Support, Non-U.S. Gov't |
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Kramer I, Vienken K, Vienken J, Zimmermann U. Magneto-electro-fusion of human erythrocytes. BIOCHIMICA ET BIOPHYSICA ACTA 1984; 772:407-10. [PMID: 6722154 DOI: 10.1016/0005-2736(84)90158-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
In inhomogeneous (static) magnetic fields close contact between 'magnetic' human erythrocytes was established. The cells were made magnetic by incubating them in a medium containing small Fe3O4 -particles which adsorbed to the outer membrane surface. Fusion was induced by applying two electric field pulses (field strength: 8.5 kV X cm-1; duration: 60 microseconds) to the magnetically collected cells. This procedure allowed the use of electrically conductive media (3 X 10(-3) omega -1 X cm-1). Fusion of red blood cells occurred very often. If cell suspensions of high density were used fusion resulted in the formation of giant red blood cells with osmotically intact membranes.
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Pukall R, Kramer I, Rohde M, Stackebrandt E. Microbial diversity of cultivatable bacteria associated with the North Sea bryozoan Flustra foliacea. Syst Appl Microbiol 2001; 24:623-33. [PMID: 11876370 DOI: 10.1078/0723-2020-00073] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The microbial diversity of cultivatable bacteria associated with the bryozoan species Flustra foliacea from the North Sea was investigated by a molecular approach. Amplified ribosomal RNA restriction analyses (ARDRA) and 16S rDNA partial sequence analysis revealed differences in the composition of cultivatable bacteria populations from single bryozoan colonies collected from two different sampling sites in the North Sea as well from one site taken at different points in time. Whereas gamma-Proteobacteria identified as Shewanella frigidimarina, Pseudoalteromonas ssp. and Psycbrobacter ssp. were predominant on samples of Flustra I (taken near the island of Helgoland), most bacteria isolated from Flustra II, originating from the Steingrund, could be affiliated to Gram-positive taxa. Survey of the bryozoan samples from the latter site in February 2000 led to the detection of a phylogenetically mixed bacterial population, consisting of gamma-, and alpha-Proteobacteria and Gram-positive bacteria with low and high GC-content (Flustra III). As these bacteria are among the most widely isolated organisms from the marine environment, it may be concluded that the bryozoan Flustra foliacea accepts colonization of surfaces by bacteria which are common inhabitants of the marine environment and which may have been transferred into this environment from terrestrial sites.
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MESH Headings
- Animals
- Base Sequence
- Bryozoa/microbiology
- Bryozoa/ultrastructure
- Cluster Analysis
- DNA Restriction Enzymes/chemistry
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- Electrophoresis, Agar Gel
- Gram-Positive Bacteria/genetics
- Gram-Positive Bacteria/isolation & purification
- Gram-Positive Bacteria/metabolism
- Microscopy, Electron, Scanning
- Molecular Sequence Data
- North Sea
- Phylogeny
- Polymerase Chain Reaction
- Proteobacteria/genetics
- Proteobacteria/isolation & purification
- Proteobacteria/metabolism
- RNA, Ribosomal, 16S/chemistry
- RNA, Ribosomal, 16S/genetics
- Ribotyping
- Sequence Analysis, DNA
- Sequence Homology, Nucleic Acid
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Markowitz M, Kramer I, Goldstein E, Perlman A, Klein D, Kramer R, Blue ML. Persistence of group A streptococci as related to penicillinase-producing staphylococci: comparison of penicillin V potassium and sodium nafcillin. J Pediatr 1967; 71:132-7. [PMID: 5006422 DOI: 10.1016/s0022-3476(67)80245-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Pluim HJ, Boersma ER, Kramer I, Olie K, van der Slikke JW, Koppe JG. Influence of short-term dietary measures on dioxin concentrations in human milk. ENVIRONMENTAL HEALTH PERSPECTIVES 1994; 102:968-71. [PMID: 9738212 PMCID: PMC1567454 DOI: 10.1289/ehp.94102968] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Breast-feeding may expose infants to high levels of toxic chlorinated dioxins. To diminish intake of these lipophilic compounds by the baby, two diets were tested for their ability to reduce concentrations of dioxins in human milk. The diets were a low-fat/high- carbohydrate/low-dioxin diet. (about 20% of energy intake derived from fat) and a high fat /low-carbohydrate/low-dioxin diet. These diets were tested in 16 and 18 breast-feeding women, respectively. The test diets were followed for 5 consecutive days in the fourth week after delivery. Milk was sampled before and at the end of the dietary regimen, and dioxin concentrations and fatty acid concentrations were determined. Despite significant influences of these diets on the fatty acid profiles, no significant influence on the dioxin concentrations in breast milk could be found. We conclude that short-term dietary measures will not reduce dioxin concentration in human milk.
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Skodda S, Kramer I, Spittler JF, Gehlen W. Non-convulsive status epilepticus in two patients receiving tiagabine add-on treatment. J Neurol 2001; 248:109-12. [PMID: 11284127 DOI: 10.1007/s004150170244] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We report two patients with epileptic syndromes who developed non-convulsive status epilepticus under adjunctive antiepileptic therapy with tiagabine. The paradoxical effect may be the result of a difference in effects between GABAA and GABAB receptors, or between GABA receptors in different regions of the brain.
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Schumann P, Tindall BJ, Mendrock U, Kramer I, Stackebrandt E. Pelczaria aurantia ATCC 49321T (=DSM 12801T) is a strain of Kocuria rosea (Flügge 1886) Stackebrandt et al. 1995. Int J Syst Evol Microbiol 2000; 50 Pt 4:1421-1424. [PMID: 10939645 DOI: 10.1099/00207713-50-4-1421] [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: 11/18/2022] Open
Abstract
Phylogenetic and chemotaxonomic analyses of Pelczaria aurantia ATCC 49321T (= DSM 12801T) indicate that this species is very closely related to Kocuria rosea. The DNA-DNA reassociation value of 87.1% determined for the type strains of the two species supports this finding. The results of phylogenetic analysis of the 16S rDNA of a subculture of the original strain of Pelczaria aurantia, deposited at the National Institutes of Health, Bethesda, MD, USA, as 'Neisseria aurantia', are identical to those for strain ATCC 49321T and indicate that Pelczaria aurantia ATCC 49321T is an authentic subculture of the original culture described by Poston (1993). On the basis of these findings it is concluded that P. aurantia ATCC 49321T and K. rosea DSM 20447T are members of the same taxon. The taxonomic consequences of this union are discussed.
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Abstract
A 15-month-old boy, thought to have a congenital myopathy, was subsequently diagnosed as having mucolipidosis type IV, with typical membranous inclusions in muscle fibers. Involvement of skeletal muscle in this lysosomal storage disease may explain the motor delay and hypotonia that are its most common presenting signs.
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Korn P, Kramer I, Schlottig F, Tödtman N, Eckelt U, Bürki A, Ferguson SJ, Kautz A, Schnabelrauch M, Range U, Kneissel M, Stadlinger B, Stadlinger B. Systemic sclerostin antibody treatment increases osseointegration and biomechanical competence of zoledronic-acid-coated dental implants in a rat osteoporosis model. Eur Cell Mater 2019; 37:333-346. [PMID: 31112281 DOI: 10.22203/ecm.v037a20] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Osseointegration of dental implants can be promoted by implant-surface modifications using bisphosphonate coatings. In addition, it is of clinical interest to promote peri-implant bone formation and to restore bony structure in low bone-mass patients. The present study evaluated a combination of an anti-resorptive zoledronic acid (ZOL) implant-coating and a systemically applied sclerostin antibody, a known bone anabolic treatment principle, versus sole sclerostin antibody treatment or ZOL implant-coating in a rat osteoporosis model. Uncoated reference surface implants or ZOL-coated implants (n = 64/group) were inserted into the proximal tibia of aged osteoporotic rats three months following ovariectomy. 32 animals of each group received once weekly sclerostin antibody therapy. Osseointegration was assessed 2 or 4 weeks post-implantation by ex vivo µCT, histology and biomechanical testing. Overall implant survival rate was 97 %. Histomorphology revealed pronounced bone formation along the entire implant length of ZOL-coated implants. At 4 weeks following implant insertion, bone-implant contact, cancellous bone mineral density and bone volume/tissue volume were significantly increased for the combination of ZOL and sclerostin antibody as compared to sclerostin antibody or ZOL implant-coating alone. Removal torque was also significantly increased in the combination therapy group relative to animals receiving only sclerostin antibody therapy or ZOL-coated implants. In an osteoporotic rat model, the combination of anti-resorptive ZOL implant-coating and systemically applied sclerostin antibody led to significantly increased peri-implant bone formation. Therefore, the combination of ZOL and the osteoanabolic sclerostin antibody was more effective than either agent alone.
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Chaigne-Delalande B, Anies G, Kramer I, Genot E. Nonadherent cells switch to a Rac-mediated, SHIP regulated, Akt activation mode for survival. Oncogene 2007; 27:1876-85. [PMID: 17906692 DOI: 10.1038/sj.onc.1210830] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Constitutively active Rac stimulates Akt activity in T lymphocytes cultured in suspension. This regulation contrasts with findings obtained in fibroblasts, endothelial or neuronal cells grown on substrate, where Akt stimulation occurs independently of Rac. We now show that V12Rac-mediated stimulation of Akt is not restricted to the hematopoietic lineage but is dependent on the adherence status of the cell. V12Rac-mediated stimulation of Akt as well as molecular association between Rac and Akt occurred exclusively in cells kept in suspension. Stimulation and complex formation are dependent on SHIP but in a manner that differs from its role in dephosphorylation of phosphoinositide lipids. Adherent cells lacking SHIP, but not those lacking PTEN, are able to activate Akt through the Rac pathway. Our data reveal the existence of a bona fide Rac to Akt signaling pathway, tightly regulated by SHIP and operational in suspended cells only. This pathway may point to an alternative survival signal that is called into action when cells lose contact with the substrate and/or with other cells.
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Koefoed P, Dalhoff K, Dissing J, Kramer I, Milman N, Pedersen P, Simonsen K, Tygstrup N, Nielsen FC. HFE mutations and hemochromatosis in Danish patients admitted for HFE genotyping. Scand J Clin Lab Invest 2003; 62:527-35. [PMID: 12512743 DOI: 10.1080/003655102321004549] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Analysis of the common C282Y and H63D mutations in the HFE gene is widely used to diagnose hereditary hemochromatosis (HH). The aim of this study was to evaluate the efficiency with which different hospitals and general practitioners select patients for HH genotype and to determine the distribution of HFE mutations in such patients. Nine hundred unrelated patients from Danish hospitals and general practitioners (group A) and 69 consecutive patients from a specialized liver unit (group B) were examined for HFE substitutions using multiplex real-time polymerase chain reaction. In group A we found 13.0% (0%) C282Y homozygotes, 5.8% (2.6%) H63D/C282Y compound heterozygotes and 1.9% (3.1%) S65C heterozygotes. The values for 420 Danish blood donors are shown in parentheses. The distribution of genotypes in group B was similar to that of the blood donors. Serum ferritin, transferrin iron saturation and pathological data were collected from 38 randomly selected C282Y homozygotes, 36 H63D/C282Y compound heterozygotes, 19 H63D heterozygotes, 17 S65C heterozygotes and 144 wild-types. All of the C282Y homozygotes and 28% of the compound heterozygotes were diagnosed as HH patients. There was no evidence of HH in the H63D homozygotes or S65C heterozygotes. Moreover, 7 wild-type patients, 2 C282Y heterozygote patients and one H63D heterozygote patient fulfilled the criteria for HH. The significant enrichment of HH among associated genotype samples submitted for HFE testing indicates that the clinical selection is generally adequate. However, the study showed substantial deviation in the selection efficiency among the various hospitals and general practitioners.
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Sacks H, Bank S, Kramer I, Novis B, Marks IN. A comparison between spectrophotometric and titrimetric methods of estimating trypsin. Gut 1971; 12:727-8. [PMID: 5098328 PMCID: PMC1411790 DOI: 10.1136/gut.12.9.727] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The spectrophotometric method described is quick and effective and a reliable alternative to a titrimetric method for measuring trypsin activity in duodenal juice.
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