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Uniparental disomy 7 in Silver--Russell syndrome and primordial growth retardation 总被引:12,自引:2,他引:12
Kotzot Dieter; Schmitt Silke; Bernasconi Fabiana; Robinson Wendy P.; Lurie Iosif W.; Ilyina Helena; Mehes Karoly; Hamel Ben C.J.; Otten Barto J.; Hergersberg Martin; Werder Edmond; Schoenle Eugen; Schinzel Albert 《Human molecular genetics》1995,4(4):583-587
Maternal uniparental disomy for the entire chromosome 7 hasso far been reported in three patients with intrauterine andpostnatal growth retardation. Two were detected because theywere homozygous for a cystic fibrosis mutation for which onlythe mother was heterozygous, and one because he was homozygousfor a rare COL1A2 mutation. We investigated 35 patients witheither the Silver-Russell syndrome or primordial growth retardationand their parents with PCR markers to search for uniparentaldisomy 7. Four of 35 patients were found to have maternal disomy,including three with isodisomy and one with heterodisomy. Thedata confirm the hypothetical localization of a maternally imprintedgene (or more than one such gene) on chromosome 7. It is suggestedto search for UPD 7 in families with an offspring with sporadicSilver-Russell syndrome or primordial growth retardation. 相似文献
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Phosphatidylcholine-Specific Phospholipase C from Listeria monocytogenes Is an Important Virulence Factor in Murine Cerebral Listeriosis 总被引:1,自引:0,他引:1 下载免费PDF全文
Dirk Schlüter Eugen Domann Christine Buck Torsten Hain Herbert Hof Trinad Chakraborty Martina Deckert-Schlüter 《Infection and immunity》1998,66(12):5930-5938
Meningoencephalitis is a serious and often fatal complication of Listeria monocytogenes infection. The aim of the present study was to analyze the role of internalin A (InlA) and B, which are involved in the invasion of L. monocytogenes into cultivated host tissue cells, and that of phosphatidylcholine-specific phospholipase C (PlcB), which mainly promotes the direct cell-to-cell spread of L. monocytogenes, in murine cerebral listeriosis by use of an InlA/B (ΔinlAB2)- and a PlcB (ΔplcB2)-deficient isogenic deletion mutant strain and the wild-type (WT) L. monocytogenes EGD. Listeria strains were directly applied to the brain, a technique which has been employed previously to study the pathogenesis of cerebral listeriosis (D. Schlüter, S. B. Oprisiu, S. Chahoud, D. Weiner, O. D. Wiestler, H. Hof, and M. Deckert-Schlüter, Eur. J. Immunol. 25:2384–2391, 1995). We demonstrated that PlcB, but not InlA or InlB, is an important virulence factor in cerebral listeriosis. Nonimmunized mice infected intracerebrally with the ΔplcB2 strain survived significantly longer and had a reduced intracerebral bacterial load compared to mice infected with the ΔinlAB2 strain or WT bacteria. In addition, immunization with the WT prior to intracerebral infection significantly increased the survival rate of mice challenged intracerebrally with the ΔplcB2 strain compared to that of mice infected with the WT or ΔinlAB2 strain. Histopathology revealed that the major difference between the various experimental groups was a significantly delayed intracerebral spread of the ΔplcB2 mutant strain, indicating that cell-to-cell spread is an important pathogenic feature of cerebral listeriosis. Interestingly, irrespective of the Listeria mutant used, the apoptosis of hippocampal and cerebellar neurons and an internal hydrocephalus developed in surviving mice, indicating that these complications are not dependent on the virulence factors InlA/B and PlcB. In conclusion, this study points to PlcB as a virulence factor important for the intracerebral pathogenesis of murine L. monocytogenes meningoencephalitis. 相似文献
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Baumgartner C Gröppel G Leutmezer F Aull-Watschinger S Pataraia E Feucht M Trinka E Unterberger I Bauer G 《Neurology》2000,55(3):432-434
ARTICLE ABSTRACT: The authors describe six patients with medically refractory temporal lobe epilepsy whose seizures were characterized by an aura of ictal urinary urge. All seizures originated in the nondominant temporal lobe as evidenced from interictal spikes, ictal EEG, and MRI. Ictal SPECT, which was obtained in two patients, showed a hyperperfusion of the insular cortex, indicating a critical role of the insula for the generation of this symptom. Ictal urinary urge represents a new lateralizing sign indicating a seizure onset in the nondominant temporal lobe. 相似文献
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Barbu E Sarvaiya I Green KL Nevell TG Tsibouklis J 《Journal of biomedical materials research. Part A》2005,74(4):598-606
Copolymeric hydrogels constituting of vinylpyrrolidone and methacrylic or acrylic acid repeat units have been prepared and investigated for their ability to act as controlled release vehicles in ophthalmic drug delivery. The materials were synthesized by radical-induced polymerization in the presence of N,N'-methylenebisacrylamide crosslinker, and the influences of network composition and drug solubility upon the swelling properties, adhesion behavior, and drug release characteristics were studied. In vitro release experiments showed that some of these materials could be useful vehicles for the delivery of drugs such as pilocarpine or chloramphenicol, while in vivo studies, using the rabbit model, confirmed their high potential for the controlled ocular delivery of pilocarpine hydrochloride. 相似文献
50.
High interindividual variability in the CD4/CD8 T cell ratio and natalizumab concentration levels in the cerebrospinal fluid of patients with multiple sclerosis 下载免费PDF全文
A. Harrer G. Pilz P. Wipfler K. Oppermann J. Sellner W. Hitzl E. Haschke‐Becher S. Afazel T. Rispens D. van der Kleij E. Trinka J. Kraus 《Clinical and experimental immunology》2015,180(3):383-392
Strongly decreased leucocyte counts and a reduced CD4/CD8 T cell ratio in the cerebrospinal fluid (CSF) of natalizumab (NZB)‐treated multiple sclerosis (MS) patients may have implications on central nervous (CNS) immune surveillance. With regard to NZB‐associated progressive multi‐focal leucoencephalopathy, we aimed at delineating a relationship between free NZB, cell‐bound NZB, adhesion molecule (AM) expression and the treatment‐associated shift in the CSF T cell ratio. Peripheral blood (PB) and CSF T cells from 15 NZB‐treated MS patients, and CSF T cells from 10 patients with non‐inflammatory neurological diseases and five newly diagnosed MS patients were studied. Intercellular adhesion molecule‐1 (ICAM‐1), leucocyte function antigen‐1 (LFA‐1), very late activation antigen‐4 (VLA‐4), NZB saturation levels, and T cell ratios were analysed by flow cytometry. NZB concentrations were measured by enzyme‐linked immunosorbent assay (ELISA). Lower NZB saturation levels (P < 0·02) and a higher surface expression of ICAM‐1 and LFA‐1 (P < 0·001) were observed on CSF CD8 T cells. CSF T cell ratios (0·3–2·1) and NZB concentrations (0·01–0·42 µg/ml) showed a pronounced interindividual variance. A correlation between free NZB, cell‐bound NZB or AM expression levels and the CSF T cell ratio was not found. Extremely low NZB concentrations and a normalized CSF T cell ratio were observed in one case. The differential NZB saturation and AM expression of CSF CD8 T cells may contribute to their relative enrichment in the CSF. The reduced CSF T cell ratio appeared sensitive to steady‐state NZB levels, as normalization occurred quickly. The latter may be important concerning a fast reconstitution of CNS immune surveillance. 相似文献