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11.
Microtubule-associated protein tau is required for axonal neurite elaboration by neuroblastoma cells. 总被引:5,自引:0,他引:5
NB2a/d1 neuroblastoma cells constitutively express multiple isoforms of the microtubule-associated protein tau and incorporate this protein into the axonal neurites elaborated during serum deprivation. To examine whether or not tau played an essential role in axonal outgrowth, cells cultured in serum-free medium were treated at 24 h intervals with antisense- and sense-oriented cDNA oligonucleotides (25 or 36 mers that span or are upstream of tau initiation codon) and were simultaneously serum deprived. Oligonucleotide uptake was confirmed by determination of intracellular levels of radiolabeled oligonucleotides. Treatment for 48 h with tau antisense oligonucleotides reversibly inhibited the expression of tau and the number of neurite-bearing cells compared with treatment with sense oligonucleotides. By contrast, tubulin expression was not affected. When cells were treated with antisense oligonucleotide simultaneously with serum deprivation, the initial outgrowth of neurites was unaffected, but continued neurite elongation was prevented. By contrast, neurite outgrowth at 4 h was inhibited when cells were pretreated with tau antisense 24 h before serum deprivation. Furthermore, intracellular delivery of anti-tau antiserum prevented neurite outgrowth and, in cells that had previously been deprived of serum for 24 h, induced retraction of existing neurites. These findings indicate that both the initiation and the continued outgrowth of neurites are dependent on tau and that pre-existing cytoplasmic pools of tau can mediate initial neuritogenesis. 相似文献
12.
J. Thiele T. K. Zirbes J. Lorenzen H. M. Kvasnicka S. Scholz A. Erdmann U. Flucke V. Diehl R. Fischer 《Annals of hematology》1997,75(1-2):33-39
In order to determine the dynamics of hematopoietic cell turnover, proliferative activity and incidence of apoptosis (programmed
cell death) were evaluated in bone marrow trephine biopsies. Selection of patients (20 in each group) included in addition
to a control group, idiopathic thrombocytopenia (ITP), reactive thrombocytosis (TH), secondary polycythemia-smokers' polyglobuly
(PG), primary (essential-hemorrhagic) thrombocythemia (PTH), polycythemia vera (PV), and finally acute myeloid leukemia (AML).
Apoptosis was demonstrated by the in situ end-labeling technique (ISEL) and proliferative activity by applying the monoclonal
antibody PC10 raised against proliferating cell nuclear antigen (PCNA). To assess dynamic features of hematopoiesis, an index
was calculated consisting of the ratio between PCNA-positive nuclei and the apoptotic cell fraction. This factor was termed
the hematopoietic turnover index (HTI). Morphometric analysis revealed that the HTI was significantly increased in AML and
PV. According to cell culture studies both disorders are characterized by either a prevalent proliferation of the myeloid
or erythroid cell mass. On the other hand, PG, PTH, and TH showed no relevant enhancement of this index in comparison to the
control specimen. In vitro experiment results are in keeping with the finding that PG and PTH are not associated with a significant
expansion of the erythroid lineage (CFU-E). Similar to ITP and TH, in PTH megakaryocyte proliferation (CFU-MEG) is the predominant
feature of cell turnover. Differences between PTH and TH are in line with the reduced in vitro formation of CFU-MEG in the
latter disorder. In conclusion, our in situ study on turnover rates of the bone marrow in various neoplastic and reactive
lesions extends previous experimental data on hematopoietic cell kinetics.
Received: 10 March 1997 / Accepted: 18 May 1997 相似文献
13.
14.
15.
M. Guillemin H. Cachier C. Chini D. Dabill D. Dahmann F. Diebold A. Fischer H.-H. Fricke J. A. Groves R. Hebisch M. Houpillart G. Israël M. Mattenklott W. Moldenhauer J. P. Sandino C. Schlums E. Sutter E. Tucek 《International archives of occupational and environmental health》1997,70(3):161-172
Object: Diesel soot has been recognized as probably carcinogenic to humans. Elemental carbon (also called black carbon) in soot
is considered at the moment as the most significant surrogate to be measured for assessing the exposure to this pollutant.
Its analysis is done by combustion in an oven and determination of the CO2 formed, after elimination of the organic fraction of the soot by heating and/or by solvent extraction. The analysis allows
determination of both fractions of the soot: “elemental carbon” (EC) and organic carbon␣(OC). The sum of EC and OC is called
TC (total carbon). Method: An informal European coordination group organized two round robin tests on filter samples collected from diluted diesel
emissions. The first round (RRT1) was performed on 13 different samples analyzed by ten laboratories. The range of loading
was 2.5 to 150 μg/cm2 of EC. No evaluation of the precision within laboratories could be made since each laboratory gave only one result per sample.
Therefore a second round (RRT2) was organized with two samples and a blank filter sent in several portions to 11 laboratories.
It should be stressed that each laboratory used its own method and that no standardization was planned at this stage. Results: Results of RRT1 showed that the coefficient of variation between laboratories decreased with higher loading and was around
10% to 15% for EC above about 20 μg/cm2. Dispersion of the results varied and it appeared that the way OC is removed from the soot is probably the most important
factor of influence. The correlation between the laboratories was good as a whole but some systematic differences could be
detected. Besides the different techniques to remove the organic carbon, the pretreatment of the filter by HCl (either as
a vapor or as a solution) to remove the inorganic carbonates (potential interference sources), is probably also a significant
factor of influence in the dispersion of the results between laboratories. It is not yet clear from these results whether
the “environmental” laboratories give different results from the “occupational” laboratories, but it is clear that their objectives
differ since for the “environmentalists”, EC is not a specific marker of diesel immissions, in contrast to the “occupationalists”.
Conclusion: It can be concluded that, although significant differences exist between laboratories they can be attributed mainly to the
narrow distribution of the results within a single laboratory, and that the overall agreement of the results for EC and TC
is fairly good. These results obtained with pure diesel engine emissions, should be complemented by field samples, but they
have already achieved relevant findings in the performance of the procedures used to assess exposure to diesel soot.
Received: 30 December 1996 / Accepted: 21 February 1997 相似文献
16.
The prognostic value of evoked responses from primary somatosensory and auditory cortex in comatose patients. 总被引:9,自引:0,他引:9
OBJECTIVE: To evaluate somatosensory and auditory primary cortices using somatosensory evoked potentials (SEPs) and middle latency auditory evoked potentials (MLAEPs) in the prognosis of return to consciousness in comatose patients. METHODS: SEPs and MLAEPs were recorded in 131 severe comatose patients. Latencies and amplitudes were measured. Coma had been caused by transient cardiac arrest (n=49), traumatic brain injury (n=22), stroke (n=45), complications of neurosurgery (n=12) and encephalitis (n=3). One month after the onset of coma patients were classified as awake, still comatose or dead. Three months after (M3), they were classified into one of the 5 categories of the Glasgow outcome scale (GOS). RESULTS: At M3, 41.2% were dead, 47.3% were conscious (GOS 3-5) and 11.5% had not recovered consciousness. None of the patients in whom somatosensory N20 and auditory Pa were absent did return to consciousness and in the post-anoxic group, reduced cortical amplitude too was always associated with bad outcome. Conversely, N20 and Pa were present, respectively, in 33/69 and 34/69 patients who did not recover. CONCLUSIONS: The prognostic value of SEPs and MLAEPs in comatose patients depends on the cause of coma. Measurement of response amplitudes is informative. Abolition of cortical SEPs and/or cortical MLAEPs precludes post-anoxic comatose patients from returning to consciousness (100% specificity). In any case, the presence of short latency cortical somatosensory or auditory components is not a guarantee for return to consciousness. Late components should then be recorded. 相似文献
17.
A O Goldstein W R Westbrook R E Howell P M Fischer 《The Journal of family practice》1992,34(6):729-734
BACKGROUND. This study reports the barriers and challenges for hospital tobacco control efforts after the institution of smoke-free policies. METHODS. Surveys of employees and inpatients of five hospitals in Augusta, Georgia, were conducted and evaluated 4 months after joint hospital implementation of smoke-free policies. A random sample of 1997 employees and a convenience sample of 517 inpatients returned usable surveys. RESULTS. Although attitudes to the hospital bans on smoking reflected strong support for smoke-free policies, four out of five hospitals reported significant implementation problems. Despite the bans, 49% of patients who were smokers continued to smoke while hospitalized, and almost one half of all hospitalized smokers had received no advice to quit smoking from a physician or a nurse since admission. Employees and patients both agreed that the smoke-free policies had benefited employees more than patients. CONCLUSIONS. Despite achieving a smoke-free status, there are many challenges that remain for comprehensive hospital tobacco-control efforts. Hospitals and health care professionals must remain particularly alert and attentive to the needs of patients and employees still addicted to tobacco. 相似文献
18.
Comparison of the inflammatory response between miniaturized and standard CPB circuits in aortic valve surgery. 总被引:1,自引:0,他引:1
Olivier M Bical Yves Fromes Didier Gaillard Marc Fischer Olivier Ponzio Philippe Deleuze Marie-Fran?oise Gerhardt Fran?ois Trivin 《European journal of cardio-thoracic surgery》2006,29(5):699-702
OBJECTIVE: One of the complications of CPB is the systemic inflammatory response syndrome (SIRS). Recent developments tend to minimize the biological impact of CPB in using miniaturized closed circuit with reduced priming volume and less blood-air interface. The benefit of these miniaturized closed circuits in terms of inflammatory response has been proved in coronary surgery. However, in open heart surgery, the CPB circuit is no more closed and the benefit of the miniaturized set-up could disappear. The aim of the study is to compare the SIRS between standard and miniaturized circuits in aortic surgery. METHODS: Forty patients who underwent singular aortic valve replacement were randomly assigned either to a standard CPB (group A, n=20) or to a miniaturized CPB (group B, n=20). Pertinent clinical and surgical data were collected. Hematological parameters (leukocyte and neutrophil counts) and biochemical parameters (C-reactive protein, cytokine tests) were determined pre-, on and post-CPB. RESULTS: There were an increase in leukocyte and neutrophil counts and a decline in hematocrit in both groups. In both groups, there was a raise after CPB, in C-reactive protein, IL-6, TNF-alpha, neutrophil elastase, and IL-10. However, the raises of elastase and TNF-alpha were significantly lower after the weaning of miniaturized CPB (116+/-46 ng/ml and 10+/-4 pg/ml, respectively) compared to standard CPB (265+/-120 ng/ml, P=0.01 and 18+/-7 pg/ml, P=0.03). The raise of IL-10 is also lower with miniaturized circuit (15+/-6 pg/ml) compared to standard circuit (51+/-26, P=0.004). CONCLUSIONS: This study demonstrates in aortic surgery, the lesser inflammatory response of a miniaturized CPB compared to a standard CPB. However, there is always some inflammation after CPB and a small bio-reactive free perfusion circuit is still to be found in open heart surgery. 相似文献
19.
INTRODUCTION: The increasing shortage of cadaveric organs makes living-related liver transplantation a more and more important option. Safety for the donor has the highest priority, and therefore detailed and thorough evaluation is needed. MATERIALS AND METHODS: All potential donors who had been evaluated at our center from January 2001 to March 2002 ( n=100) were included in a retrospective study to analyse the qualitative, logistical, and economic aspects of the evaluation. RESULTS: Seventy-three percent of the potential donors were found to be unsuitable for living donation during the evaluation process. The main reasons were: uncompatible blood group, availability of cadaveric transplant by Eurotransplant, steatosis of more than 10% of hepatocytes in liver biopsy, insufficient liver volume, and psychosocial reasons. The expenditure for all scheduled investigations was 4,469 euro for a complete evaluation. CONCLUSION: While on the one hand, high standards of the evaluation process must be guaranteed, insufficient reimbursement on the other should not lead centers to reduce either quantity or quality of necessary examinations entered in the evaluation protocol. 相似文献
20.
D Fischer D Labayle J M Versapuech D Grange F Kemeny 《Gastroentérologie clinique et biologique》1987,11(6-7):514-517
We report the case of a 51 year-old man who developed candidiasis of the small bowel associated with intestinal perforation. This condition is very rarely recognized ante mortem. Here, the diagnosis was established by pathological examination of a surgically resected specimen of small bowel at the time of surgery. A complete work-up failed to disclose any predisposing condition to digestive candidiasis. Antifungal therapy resulted in complete recovery. 相似文献