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101.
Maria C. Kuppner Marie-France Hamou Nicolas de Tribolet 《Journal of neuroimmunology》1990,29(1-3):229-238
Frozen tissue sections obtained from human glioblastomas, brain tumor metastases and normal brain were examined for the expression of molecules known to be involved in lymphocyte activation and/or adhesion and migration. The molecules studied included CD3, CD45R, UCHL-1 (CD45RO), lymphocyte function-associated antigen 1 (LFA-1) (CD11a, CD18), intercellular adhesion molecule 1 (ICAM-1) (CD54), 4B4 (CD29), CD44, CD2, and LFA-3 (CD58). CD3+ lymphocytes infiltrating human glioblastomas and brain tumor metastases expressed LFA-1 alpha and beta. Many cells were also UCHL-1+ whereas only a small percentage were CD45R+. CD2+ lymphocytes were also present. Tumor-infiltrating lymphocytes (TIL) were found to be negative for CD29, which was, however, expressed on intratumoral vessels in addition to vessels found in normal brain. Glioblastoma cells and intratumoral vessels expressed ICAM-1 whereas no ICAM-1 was found on TIL or on normal brain. Glioblastoma cells also expressed high levels of both CD44 and LFA-3 whereas TIL were negative for these antigens. CD44 was also expressed on certain regions of normal brain. Antibodies to LFA-1 alpha and -beta and ICAM-1 could significantly block the binding of lymphokine-activated killer (LAK) cells or TIL to human glioblastoma cells suggesting that these molecules play a role in the binding and subsequent migration of lymphocytes into brain tumor tissue. 相似文献
102.
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104.
Féras Chéhadé Claire de Labriolle-Vaylet Nicole Moins Marie-France Moreau Janine Papon Pierre Labarre Pierre Galle Annie Veyre Elif Hindié 《Journal of nuclear medicine》2005,46(10):1701-1706
Further development of nuclear medicine for imaging and internal radiotherapy demands a precise knowledge of the tissue and cellular distribution of radiopharmaceuticals. Ion microscopy (secondary ion mass spectrometry [SIMS]) may be particularly useful in this respect. We used SIMS to study the biodistribution of the melanoma-targeting molecule N-(2-diethylaminoethyl)-4-iodobenzamide (I-BZA), both in its native state and radiolabeled with (14)C. METHODS: C57BL6/J1/co mice bearing pulmonary colonies of B16 melanoma cells were injected with I-BZA or (14)C-I-BZA. Appropriate tissues were fixed and included in epoxy embedding resin for SIMS studies. The distribution of unlabeled I-BZA was studied by detecting its stable iodine atom ((127)I). (14)C-I-BZA distribution was studied by dual detection of (127)I and (14)C. The time course of I-BZA concentrations at sites of tissue fixation was studied by measuring the signal ratio of (14)C and the naturally occurring isotope (13)C. RESULTS: SIMS showed that I-BZA concentrated in the cytoplasm of tumoral melanocytes (melanoma cells) and in the cytoplasm of tumor-infiltrating macrophages (melanophages). I-BZA was also detected in the cytoplasm of normal melanocytes in the pigmented structures of skin and eye. Interpretation of I-BZA distribution by using electron micrographs of adjacent sections showed that the intracytoplasmic melanin-rich organelles (melanosomes) were responsible for I-BZA retention. The distributions of (127)I and (14)C after (14)C-I-BZA injection were identical, even when I-BZA was separately labeled with (14)C at 2 different positions, indicating the stability of the amide bond of I-BZA. The time course of the (14)C/(13)C ratio in the melanosomes of melanoma cells suggested a retention half-life of about 38 h. CONCLUSION: Contrary to previous suggestions that I-BZA fixes principally to sigma-1 membrane receptors, our results strongly indicate that I-BZA associates with intracytoplasmic melanin pigments. Early I-BZA accumulation, in both melanocytes and melanophages, suggests that this compound fixes to preformed melanin rather than being incorporated during de novo melanin synthesis. These quantitative and qualitative data obtained with I-BZA illustrate the excellent potential of SIMS for studying the biologic fate of radiopharmaceuticals. 相似文献
105.
Mahemuti A Meneveau N Seronde MF Schiele F Mercier M Racadot E Bassand JP 《中华医学杂志(英文版)》2007,120(22):1986-1991
Background Early local platelet activation after coronary intervention identifies patients at increased risk of acute stent thrombosis (AST). However, early changes in platelet activation in coronary circulation following drug-eluting stent (DES) implantation have never been reported.
Methods In a prospective study of 26 consecutive elective stable angina patients, platelet activation was analyzed by measuring soluble glycoprotein V (sGPV) and P-selectin (CD62P) before and after implantation of either DES or bare metal stent (BMS). All patients were pretreated with clopidogrel (300 mg loading dose) and aspirin (75 mg orally) the day before the procedure. Blood samples were drawn from the coronary ostium and 10 - 20 mm distal to the lesion site.
Results Consistent with the lower baseline clinical risk, the levels of CD62P and sGPV were within normal reference range, both in the coronary ostium and distal to the lesion before percutaneous coronary intervention (PCI) procedure. The levels of CD62P and sGPV did not change significantly (CD62P: (31.1 ± 9.86) ng/ml vs (29.5 ± 9.02) ng/ml, P=0.319 and sGPV: (52.4 ± 13.5) ng/ml vs (51.8 ± 11.7) ng/ml, P=0.674, respectively) after stent implantation when compared with baseline. Changes in these platelet activation markers did not differ between stent types.
Conclusions Intracoronary local platelet activation does not occur in stable angina patients before and immediately followina DES implantation when dual anti-Dlatelet is administered. 相似文献
106.
Saugier-Veber P Bonnet C Afenjar A Drouin-Garraud V Coubes C Fehrenbach S Holder-Espinasse M Roume J Malan V Portnoi MF Jeanne N Baumann C Héron D David A Gérard M Bonneau D Lacombe D Cormier-Daire V Billette de Villemeur T Frébourg T Bürglen L 《Human mutation》2007,28(11):1098-1107
Sotos syndrome is an overgrowth syndrome characterized by distinctive facial features, learning difficulties, and macrocephaly with frequent pre- and postnatal overgrowth with advanced bone age. Here, we report on our experience in the molecular diagnostic of Sotos syndrome on 116 patients. Using direct sequencing and a quantitative multiplex PCR of short fluorescent fragments (QMPSF)-based assay allowing accurate detection of both total and partial NSD1 deletions, we identified NSD1 abnormalities in 104 patients corresponding to 102 Sotos families (90%). NSD1 point mutations were detected in 80% of the index cases, large deletions removing the NSD1 gene entirely in 14%, and intragenic NSD1 rearrangements in 6%. Among the 69 detected distinct point mutations, 48 were novel. The QMPSF assay detected an exonic duplication and a mosaic partial deletion. QMPSF mapping of the 15 large deletions revealed the heterogeneity of the deletions, which vary in size from 1 to 4.5 Mb. Clinical features of NSD1-positive Sotos patients revealed that the phenotype in patients with nontruncating mutations was less severe that in patients with truncating mutations. This study confirms the heterogeneity of NSD1 alterations in Sotos syndrome and therefore the need to complete sequencing analysis by screening for partial deletions and duplications to ensure an accurate molecular diagnosis of this syndrome. 相似文献
107.
The DNA damage signaling pathway is a critical mediator of oncogene-induced senescence 总被引:5,自引:0,他引:5
Here we report that RNA interference against ATM inhibited p53 accumulation in cells expressing oncogenic STAT5 and cooperated with Rb inactivation to suppress STAT5A-induced senescence. Knocking down ATM was also effective to bypass E2F1-induced senescence and in combination with Rb inactivation, inhibited RasV12-induced senescence. Cells that senesced in response to ca-STAT5A or RasV12 accumulated DNA damage foci and activated ATM, ATR, Chk1, and Chk2, indicating that aberrant oncogene activation induces a DNA damage signaling response. Intriguingly, bypassing oncogene-induced senescence by inactivation of p53 and Rb did not eliminate the accumulation of oncogene-induced DNA damage foci (ODDI), suggesting a mechanism that may limit transformation in immortalized cells. 相似文献
108.
Gruchy N Jacquemont ML Lyonnet S Labrune P El Kamel I Siffroi JP Portnoï MF 《American journal of medical genetics. Part A》2007,(20):2417-2422
Inverted duplications with terminal deletions have been reported in an increasing number of chromosomes and are probably more frequent than suspected until recently. We describe the cytogenetic and molecular characterization of an inverted duplication of chromosome 2p in an 8-year-old girl. Firstly interpreted as partial duplication 2p, the rearrangement was in fact an inverted duplication associated with a terminal deletion of the short arm of the rearranged chromosome 2, the latter not being detectable by cytogenetic analysis. The complete karyotype was: 46,XX,add(2)(p23)dn.ish inv dup del(2)(:p23.2-->p25.3::p25.3-->qter) (wcp2+,N-MYC++,2pter-)dn. We precisely define the extension of both the duplication and the deletion using bacterial artificial chromosomes clones spanning the regions. The size of the inverted duplicated segment was estimated to be 28 Mb, spanning from 2p23.2 to 2p25.3, and an approximately 1.6 Mb segment at 2pter-p25.3 was deleted in the abnormal chromosome. The physical findings noted in our patient include prominent forehead, hypertelorism, flat nasal bridge, and low-set and large ears. In addition, she had congenital heart defect and scoliosis. Her psychomotor development was severely delayed from the beginning. All these clinical features are the same as observed for the typical trisomy 2p23-pter syndrome. The phenotypic effects of the terminal deletion of 2p in addition to the trisomy are discussed. This is the third patient presenting with a severe clinical phenotype and a de novo inv dup del (2p). 相似文献
109.
Kolb S Radon K Valois MF Héguy L Goldberg MS 《Archives of environmental & occupational health》2007,62(4):169-176
The authors' purpose in this study was to determine whether changes in weather conditions were associated with daily mortality among people aged 65 years and older diagnosed as having congestive heart failure in Montreal, Canada, and who died in the urban area between 1984 and 1993. The authors used a time-stratified case-crossover design and adjusted the models for nitrogen dioxide and ozone. They found a strong nonlinear association with maximum temperature in the warmer months of the year, with a threshold at about 25 degrees C. The authors observed no associations after lag 3 days. In the cold period, they found that risks increased linearly with increasingly colder temperatures, but only after lag 2 days. The authors found no associations with relative humidity. For change in barometric pressure from the previous day, they found no associations in the cold period, but an increase in pressure from the previous day increased risk for lags 0 or 1 days. The authors found some differences between men and women. 相似文献
110.
OBJECTIVE: Seniors use a wide variety of health services delivered by numerous practitioners and organizations. Self-report is the most accessible and cost-effective method to collect information on their use. It is thus important to demonstrate the reliability of this approach. STUDY DESIGN AND SETTING: As part of a longitudinal study on the effect of an integrated service delivery system, participants (or their proxies) were instructed to use a calendar to record their use of health services. Every 2 months, an interviewer collected use since the last phone contact. A subsample was recontacted by the same or another interviewer to estimate test-retest and interinterviewer reliability, respectively. Data collections were compared using delta and weighted kappa as well as intraclass correlation coefficients. RESULTS: Almost perfect agreement was obtained for hospitalization, day surgery, visits to general practitioners and medical specialists, help for home maintenance, and use of voluntary services. Agreement was substantial for visits to the emergency room and home help for personal care. For visits to or by nurses and other health professionals, agreement can be qualified as moderate-to-substantial. CONCLUSION: Assisted self-report of health-services use by older adults or their proxies through bimonthly phone calls is reliable. 相似文献