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41.
Podlowski S Wenzel K Luther HP Müller J Bramlage P Baumann G Felix SB Speer A Hetzer R Köpke K Hoehe MR Wallukat G 《Journal of molecular medicine (Berlin, Germany)》2000,78(2):87-93
A substantial body of evidence suggests involvement of the human beta1-adrenoceptor (beta1-AR) gene in the pathophysiology of dilated cardiomyopathy (DCM), a severe heart disease of significant public health impact. Beta1-AR-mediated signal transduction is dramatically altered due to downregulation, resulting in an impairment of myocardial response. The important role of genetic factors in idiopathic dilated cardiomyopathy (IDCM) recently recognized, we analyzed this prime candidate gene for genetic variation in carefully selected patients and controls. In this preliminary study, 18 single nucleotide polymorphisms were observed, 17 of which were located in the N-terminal and C-terminal region of the coding exon, resulting in 7 amino acid exchanges: Ser-49-Gly, Ala-59-Ser, Gly-389-Arg, Arg-399-Cys, His-402-Arg, Thr-404-Ala, and Pro-418-Ala. These mutations resulted in 11 different beta1-AR genotypes. Importantly, the genotypes carrying the Ser-49-Gly mutation in the N-terminus of the molecule in a heterozygous or homozygous form were observed significantly more frequently in the group of IDCM patients. The present results may provide a clue on the molecular mechanisms involved in IDCM, and add moreover interesting information on nature, distribution, and evolutionary aspects of sequence variation in human adrenergic receptor genes. 相似文献
42.
Philippe Rondou Marcel Van Beylen Celest Samyn Gert S'Heeren Andre Persoons 《Macromolecular chemistry and physics.》1992,193(12):3045-3055
The synthesis and second harmonic coeficients d33, d 31 and the susceptibilities χ(2) are reported of three series of (co)polymethacrylates that possess 4-(2,2-dicyanovinyl)- or 4-(2-cyano-2-methoxycarbonyl)vinyl-N,N-dialkylaniline (P1 and P2), 4-(2,2-dicyanovinyl)- or 4-(2-cyano-2-methoxycarbonyl)vinyl-(-piperidino)benzene (P5 and P6) and 4-(2,2-dicyano)- or 4-(2-cyano-2-methoxycarbonyl)vinyl-1-alkoxybenzene (P3 and P4) dyes 1 System. names of the monomers see Exptl. part. . The second-order nonlinear optical properties of corona-poled aligned polymer films were evaluated by second harmonic generation measurements. The χ values for the P1 and P2 polymers vary from 58 to 318, respectively 32 to 106 · 10?9 esu, for P3 and P4 from 7,6 to 19, respectively 4,4 to 7,4 · 10 ?9 esu and for P5 and P6 from 219 to 42,8 respectively 28,1 to 8,1 · 10?9 esu, depending on the dye chromophore concentration incorporated in the polymer structure. 相似文献
43.
44.
Joachim Böttcher M.D. Alexander Pfeil Anders Rosholm Ph.D. Max-Ludwig Schäfer Ansgar Malich M.D. Alexander Petrovitch M.D. Bettina Seidl Gabriele Lehmann M.D. Hans-Joachim Mentzel M.D. Gert Hein M.D. Gunter Wolf M.D. Werner A. Kaiser M.D. M.S. 《Journal of digital imaging》2006,19(3):279-288
Purpose Our study evaluates digital x-ray radiogrammetry (DXR) and Radiogrammetry Kit (RK) as a new diagnostic method for the measurement
of disease-related osteoporosis including quantification of joint space narrowing dependent on the severity of rheumatoid
arthritis (RA).
Materials and Methods A total of 172 unselected patients with RA underwent computerized measurements of bone mineral density (BMD) and metacarpal
index (MCI) by DXR, as well as a semiautomated measurement of joint space distances at the metacarpal–phalangeal articulation
(JSD-MCP 2–5), both were analyzed from plain radiographs of the nondominant hand.
Results Correlations between DXR-BMD and DXR-MCI vs. parameters of RK were all significant (0.34 < R < 0.61; p < 0.01). An expected negative association was observed between RK parameters and the different scoring methods (−0.27 < R < −0.59). The maximum relative decrease in BMD vs. MCI as measured by DXR between the highest and lowest RA severity group
was −27.7% vs. −27.5% (p < 0.01) for the modified Larsen Score, whereas the minimal value of relative DXR-BMD and DXR-MCI reduction could be documented
for the Sharp Erosion Score (−20.8% vs. −26.8%; p < 0.01). The relative reduction of mean JSD-MCP using RK significantly varied from −25.0% (Sharp Erosion Score) to −41.2%
(modified Larsen Score). In addition, an excellent reproducibility of DXR and RK could be verified.
Conclusion DXR in combination with RK could be a promising, widely available diagnostic tool to supplement the different scoring methods
of RA with quantitative data, allowing an earlier and improved diagnosis and more precision in determining disease progression. 相似文献
45.
D. J. Schendel Ralph Oberneder Christine S. Falk Petra Jantzer Susanne Kressenstein Barbara Maget Alfons Hofstetter Gert Riethmüller Elfriede Nößner 《Journal of molecular medicine (Berlin, Germany)》1997,75(6):400-413
Renal cell carcinomas belong to the small group of tumors that are able to induce antitumor responses. Here we describe two
general types of cytotoxic effector lymphocytes that can eliminate autologous tumor cells and discuss the role that major
histocompatibility complex encoded molecules play in governing their specificities. Improved understanding of the cellular
and molecular basis of renal cell carcinoma recognition opens new avenues of research with the potential to develop better
immunotherapies for patients with metastatic disease.
Received: 24 July 1996 / Accepted: 1 November 1996 相似文献
46.
Schollen E Matthijs G Gewillig M Fryns JP Legius E 《European journal of human genetics : EJHG》2003,11(1):85-88
Noonan syndrome (NS, MIM 163950) is an autosomal dominant condition characterised by facial dysmorphy, congenital cardiac defects and short stature. Recently missense mutations in PTPN11, the gene encoding the nonreceptor protein tyrosine phosphatase SHP-2 on 12q24, were identified in 50% of analysed Noonan cases. A large four-generation Belgian family with NS and some features suggestive of cardio-facio-cutaneous syndrome (CFC) was previously used to fine map the Noonan syndrome candidate region to a 5 cM region in 12q24. We now report the identification of a mutation (Gln79Arg) in the PTPN11 gene in this large family. In D. melanogaster and C. elegans the PTPN11 gene has been implicated in oogenesis. In this family two affected females had dizygous twins. This suggests that PTPN11 might also be involved in oogenesis and twinning in humans. 相似文献
47.
Varsamos S Diaz JP Charmantier G Blasco C Connes R Flik G 《Anatomy and embryology》2002,205(3):203-213
Location and morphology of chloride cells were studied in the sea bass ( Dicentrarchus labrax) from hatching to the juvenile stage to determine the development of the adult osmoregulatory function as seen in adult fish. During the studied developmental sequence changes were observed in the location, number, size and structure of these cells, that were studied by microscopy (light, scanning electron, transmission electron and confocal) and immunocytochemistry. Chloride cells were found on the tegument and on the gills. They were present on the tegument already at hatching, before the development of the gills. Their density as well as their association in multicellular complexes decreased during the postembryonic development. In old larvae and in juveniles, cutaneous chloride cells were associated with the fins, the developing scales and the lateral line. Gills developed gradually during the prelarval stage and the gill arches were present at mouth opening. At that time chloride cells were already numerous on the gill arches. In older larvae, during the progressive development of the gill filaments, chloride cells were numerous on these structures and formed multicellular complexes. Several stages in the differentiation of these cells were studied, including the development of the tubulovesicular system at the end of the prelarval stage, as well as the stratification appearance of the cytoplasm that was concomitant with the considerable development of the tubular system and its association with the endoplasmic reticulum during the larval period. The involvement of different epithelia in the osmoregulatory process during the postembryonic development of this species, as well as the role of chloride cells during successive developmental stages, is discussed. 相似文献
48.
Kloover JS van den Bogaard AE van Dam JG Grauls GE Vink C Bruggeman CA 《Virus research》2002,85(2):163-172
The salivary glands are the major sites of persistent replication of rat cytomegalovirus (RCMV). At several months post infection (pi), infectious RCMV is usually still produced in the salivary glands but not in any other organ or tissue of the rat. To investigate whether the persistence of RCMV in the salivary glands is crucial to the pathogenesis of viral infection, we monitored the progression of RCMV-induced disease in rats from which the salivary glands had been surgically removed (desalivated) as well as in sham-operated rats, both after a lethal and sublethal challenge with RCMV. Desalivation did not have a significant effect on either RCMV-induced morbidity or mortality. As expected, at 1 year pi, relatively high levels of infectious virus were detected in the salivary glands of sham-operated rats, whereas neither infectious virus nor RCMV DNA could be detected in liver, spleen and lungs of these animals. Infectious virus and viral DNA were also undetectable in organs from desalivated animals at 1 year pi. Surprisingly, a difference was found between desalivated and sham-operated rats in the titers of anti-RCMV IgG antibodies, which were significantly higher in sham-operated rats than in desalivated animals at 183, 295 and 365 days pi. This finding indicates that the persistence of RCMV in the salivary glands may contribute significantly to the anti-RCMV humoral immunity of infected rats. 相似文献
49.
Albuisson J Pêcheux C Carel JC Lacombe D Leheup B Lapuzina P Bouchard P Legius E Matthijs G Wasniewska M Delpech M Young J Hardelin JP Dodé C 《Human mutation》2005,25(1):98-99
Kallmann syndrome (KAL) combines hypogonadotropic hypogonadism and anosmia. Hypogonadism is due to Gonadotropin Releasing Hormone (GnRH) deficiency and anosmia is related to hypoplasia of the olfactory bulbs. Occasional symptoms include renal agenesis, bimanual synkinesia, cleft lip palate, dental agenesis. KAL is genetically heterogeneous and two genes have so far been identified, namely KAL1 (Xp22.3) and FGFR1/KAL2 (8p12), which underlie the X chromosome‐linked form and an autosomal dominant form of the disease, respectively. We studied a cohort of 98 unrelated Caucasian KAL patients. We identified KAL1 mutations in 14 patients, of which 7 (c.3G>A (p.M1?), g.IVS1+1G>T, c.570_571insA (p.R191fsX14), c.784G>C (p.R262P), c.958G>T (p.E320X), c.1651_1654delinsAGCT (p.P551_E552delinsSX), c.1711T>A (p.W571R)) have not been previously reported. In addition, we found FGFR1 mutations in 7 patients, namely c.303G>A (p.V102I), C.385A>C (p.D129A), c.810G>A (p.V273M), c.1093_1094delAG (p.R365fsX41), c.1561G>A (p.A520T), c.1836_1837insT (p.Y613fsX42), c.2190C>G (p.Y730X), all of which were novel mutations. In this study, unilateral renal agenesis and bimanual synkinesia were exclusively found associated with KAL1mutations, cleft palate and dental agenesia with FGFR1mutations. © 2004 Wiley‐Liss, Inc. 相似文献
50.
Datema G van Meir CA Kanhai HH van den Elsen PJ 《American journal of reproductive immunology (New York, N.Y. : 1989)》2003,49(4):193-201
PROBLEM: The unusual pattern of human leukocyte antigen (HLA) expression on human trophoblasts could play an important role in successful pregnancy outcome. To determine whether alterations in HLA expression are associated with pregnancy abnormalities we have investigated expression of these antigens on chorionic and extravillous cytotrophoblasts. METHODS: Frozen tissue sections of placenta and fetal membranes were collected after pre-term spontaneous delivery, severe pre-eclampsia pre-term Caesarean section, normal term delivery and term Caesarean section. HLA expression was analyzed by immunohistochemistry. RESULTS: We did not observe differences in the expression of HLA on chorionic and extravillous cytotrophoblasts in pregnancy abnormalities. However, we noted higher expression levels of HLA class Ia molecules in amnion epithelial cells in pre-term deliveries. Furthermore, in severe pre-eclampsia the number of extravillous cytotrophoblast islands were elevated when compared with pre-term deliveries. CONCLUSIONS: No alterations in expression of HLA class Ia, HLA-G and HLA class II on human trophoblasts in pregnancy abnormalities were seen. 相似文献