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91.
van der Loo B Oechslin E Jenni R 《The New England journal of medicine》2002,347(12):949; author reply 949
92.
Sasse-Klaassen S Gerull B Oechslin E Jenni R Thierfelder L 《American journal of medical genetics. Part A》2003,(2):162-167
Isolated noncompaction of the ventricular myocardium (INVM, MIM 300183 and 604169) is a congenital unclassified cardiomyopathy with numerous prominent trabeculations and deep intertrabecular recesses in a hypertrophied and hypokinetic myocardium. Mutations in the G4.5 gene result in a wide spectrum of severe infantile X-linked cardiomyopathic phenotypes including Barth syndrome with dilated cardiomyopathy and INVM. Molecular genetic analysis of INVM has only been performed in pediatric patients. Although adult INVM patients show similar cardiac abnormalities, the influence of genetic factors, especially of mutations in G4.5, is unknown. We analyzed 25 adult INVM patients for the presence of mutations in the G4.5 gene and performed a pedigree analysis of probands. Mutations were not found in the coding sequence or splice sites of G4.5. Systematic analysis of relatives from seven of nine probands showed multiple affected members consistent with an autosomal dominant pattern of inheritance in the majority of cases. We conclude that INVM in the adult is an autosomal dominant disorder rarely caused by mutations in G4.5 and therefore genetically distinct from infantile X-linked cases. 相似文献
93.
Studies on the origin of redox enzymes in seminal plasma and their relationship with results of in-vitro fertilization 总被引:3,自引:0,他引:3
Yeung CH; Cooper TG; De Geyter M; De Geyter C; Rolf C; Kamischke A; Nieschlag E 《Molecular human reproduction》1998,4(9):835-839
Glutathione (GSH), GSH peroxidase (GPX), GSH reductase (GRD), superoxide
dismutase (SOD) and catalase-like enzyme activity were quantified in
seminal plasma from normozoospermic patients, men with known distal ductal
occlusion, proven fathers and male partners of couples receiving in-vitro
fertilization (IVF) treatment for both male and female causes. Glutathione
was non-detectable (< 2.5 microM) in seminal plasma. None of the enzyme
activities per unit volume were lower in semen from vasectomized men,
suggesting that they did not originate substantially from the testis or
epididymis. The strongest relationships between enzyme activities and
accessory gland markers were between zinc and GRD (r = 0.678), SOD (r =
0.602) and GPX (r = 0.548), suggesting a largely prostatic origin of these
enzymes. Only weak relationships between accessory gland markers and
catalase-like activity suggested a multi-glandular source of this enzyme.
There was no relationship between the activity of any of the enzymes in the
IVF patients with their fertilization rates in vitro or the establishment
of pregnancy after IVF. Nor was there any correlation of enzyme activity
with the morphology and percentage of motile spermatozoa in semen or with
the percentage motility of spermatozoa immediately after swim-up or after
overnight incubation. These findings suggest that the protective enzymes in
the seminal plasma are contributed largely by the prostate and little by
the epididymis, and that in most cases of IVF, they have no major influence
on the outcome.
相似文献
94.
Maries F. van den Broek David Kgi Rolf M. Zinkernagel Hans Hengartner 《European journal of immunology》1995,25(12):3514-3516
Adaptive immune surveillance by T cells against infections and tumors depends on the presence of antigenic peptides presented by major histocompatibility complex (MHC) molecules. If antigenic tumor-specific peptides or MHC class I molecules are absent, the adaptive T cell immune response fails. Natural killer (NK) cells seem to complement the specific T cells by recognizing target cells lacking MHC class I (e.g. RMA-S). The role of perforin, which is crucially involved in T cell and NK cell-mediated target cell lysis, was evaluated in mice lacking perforin with respect to their capacity to eliminate a syngeneic lymphoid tumor. Here, we show that growth of MHC class I? RMA-S tumor cells in unprimed mice was controlled by NK cells through perforin-dependent cytotoxicity. 相似文献
95.
Detection of perforin and granzyme A mRNA in infiltrating cells during infection of mice with lymphocytic choriomeningitis virus 总被引:12,自引:0,他引:12
Christoph Müller David Kgi Toni Aebischer Bernhard Odermatt Werner Held Eckhard R. Podack Rolf M. Zinkernagel Hans Hengartner 《European journal of immunology》1989,19(7):1253-1259
The analysis of gene expression in cytotoxic T cells by in situ hybridization of serial liver and brain sections from mice infected with lymphocytic choriomeningitis virus (LCMV) and immunostaining with T cell marker- and virus-specific antibodies revealed a close histological association of infiltrating lymphocytes expressing the perforin and granzyme A genes with virally infected cells. Maximal frequency of perforin and granzyme A mRNA-containing cells on liver sections preceded by about 2 days maximal LCMV-specific cytotoxicity of the lymphoid liver infiltrating cells. These results are most consistent with an involvement of perforin and granzyme A in cell-mediated cytotoxicity in vivo. 相似文献
96.
Correction of EOG Artifacts in Event-Related Potentials of the EEG: Aspects of Reliability and Validity 总被引:3,自引:0,他引:3
Correction of EOG artifacts using a regression approach is evaluated in terms of reliability and validity. Transmission rates are estimated for eight EEG channels in 67 subjects. The trimmed group means of these rates are shown to provide reliable measures. Eye artifact correction based on these group means is superior to the conventional rejection in terms of reducing correlation between EOG and EEG. 相似文献
97.
N-Acetyltransferase, which is suggested to be responsible for the production of N
1-acetylspermidine in Leishmania amazonensis and to be involved in the process of inactivation and degradation of excessive polyamines, was partially purified and characterized.
Among the substrates tested, sym-norspermidine, sym-norspermine, and 1,3-diaminopropane had the highest reaction rates, but the naturally occurring polyamines spermine and spermidine
were also acetylated at considerable rates, whereas putrescine was a poor substrate. The Michaelis constants (K
m values) for spermine and spermidine were 0.66 and 3.3 mM, respectively. The Km value for acetylcoenzyme A (acetyl-CoA) was determined to be 34 μM. CoA inhibited the reaction in a competitive manner; the inhibition constant was 5 μM. The enzyme showed an apparent relative molecular mass of 35,000.
Received: 16 November 1995 / Accepted: 10 January 1996 相似文献
98.
Inhibitory effects of clonidine on the allergen-induced wheal-and-flare reactions in patients with extrinsic asthma 总被引:2,自引:0,他引:2
Bjrn R. Lindgren M.D. Astrid Brundin M.D. Rolf G. G. Andersson Ph.D. 《The Journal of allergy and clinical immunology》1987,79(6):941-946
We investigated the possibility that clonidine, an alpha 2-adrenoceptor agonist, can reduce the wheal-and-flare reactions induced by intradermal injections of allergen in patients with extrinsic asthma. Ten adult subjects with asthma with positive skin tests to one or several pollens were selected. They received, in random order and double-blind manner, clonidine (two doses, each 75 micrograms) or placebo for 3 days, and then, after a 1-week washout period, they crossed over to the other treatment for 3 days. Treatment with clonidine reduced the area of wheal-and-flare reaction induced by allergen without significantly changing the blood pressure or the plasma cortisol level. There was a drop in the histamine content of leukocytes and in the number of eosinophils in peripheral blood after allergen challenge during the placebo treatment, whereas clonidine prevented these changes. The results suggest that treatment with clonidine can reduce the inflammatory reactions induced by allergens in subjects with extrinsic asthma. 相似文献
99.
Ralf Thomann Chun Wang Jrg Kressler Rolf Mülhaupt 《Macromolecular chemistry and physics.》1996,197(3):1085-1091
The formation of holes during the late stage of the isothermal crystallization in thin films of isotactic poly(propylene) between two cover glasses was observed by light microscopy and atomic force microscopy. This behavior can be described consistently by the well-known negative pressure effect. Light microscopy reveals the simultaneous and sudden occurrence of a large number of small holes at the liquid-solid interface after the liquid in front of the spherulites is completely confined by other spherulites for a certain time interval. In exceptional cases only a few holes appear and finally large cavities are formed. Atomic force microscopy measurements carried out in the height mode are able to prove the hole formation in front of the spherulites. Furthermore, a substantial thinning of the two-dimensional spherulites in thin films can be observed prior to the hole formation. 相似文献
100.
The effects of fish sera on the growth and fine structure of infective larvae of the eel-pathogenic acanthocephalanParatenuisentis ambiguus (Eoacanthocephala: Tenuisentidae) were studied under in vitro conditions using sera from the final hostAnguilla anguilla and from two accidental fish hosts as well as fetal calf serum. As controls larvae were also kept in medium in the absence of serum and in experimentally infected eels. Sera from the accidental fish hosts carp and rainbow trout exerted toxic effects on the acanthocephalans. Worms maintained in medium containing sera from these two fish were contracted and displayed inverted probosces. Moreover, the tegument exhibited vacuolization and the formation of necrotic areas, including lysis of the mitochondria. Due to these effects, the parasites died at 21 (rainbow trout) or 21–50 days (carp) postincubation. Eel sera had no toxic effect on the infective larvae. The growth of the larvae in medium depended on the composition of the latter, but was reduced as compared with that in the natural final host. Based on these results, we conclude that components of the hosts' blood sera play a role in the determination of the host specificity ofP. ambiguus. 相似文献