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991.
Protection of zinc against tumor necrosis factor induced lethal inflammation depends on heat shock protein 70 and allows safe antitumor therapy 总被引:1,自引:0,他引:1
Van Molle W Van Roy M Van Bogaert T Dejager L Van Lint P Vanlaere I Sekikawa K Kollias G Libert C 《Cancer research》2007,67(15):7301-7307
Tumor necrosis factor (TNF)-induced inflammation prevents its broad application as an antitumor agent. We here report that addition of ZnSO(4) to the drinking water of mice induces expression of heat shock protein 70 (HSP70) in several organs, notably the gastrointestinal track. Zinc conferred dose-responsive protection against TNF-induced hypothermia, systemic induction of interleukin-6 and NO(x), as well as against TNF-induced bowel cell death and death of the organism. The protective effect of zinc was completely absent in mice deficient in the major HSP70-inducible gene, hsp70.1, whereas transgenic mice constitutively expressing the human HSP70.A gene, under control of a beta-actin promoter, was also protected against TNF, indicating that an increase in HSP70 is necessary and sufficient to confer protection. The therapeutic potential of the protection induced by ZnSO(4) was clearly shown in a TNF/IFNgamma-based antitumor therapy using three different tumor models. In hsp70.1 wild-type mice, but not in hsp70.1-deficient mice, zinc very significantly protected against lethality but left the antitumor effect intact. We conclude that zinc protects against TNF in a HSP70-dependent way and that protection by zinc could be helpful in developing a safer anticancer therapy with TNF/IFNgamma. 相似文献
992.
Bay JO Jacques-Olivier B Linassier C Claude L Biron P Pierre B Durando X Xavier D Verrelle P Pierre V Kwiatkowski F Fabrice K Rosti G Giovanni R Demirer T Taner D;EMBT solid tumors working party 《International journal of cancer. Journal international du cancer》2007,120(8):1782-1786
Radiotherapy plus concomitant and adjuvant temozolomide have demonstrated improved survival for glioblastoma. However, prognosis remains poor. High-doses chemotherapy with carmustine is another way to improve response and survival by increasing the dose delivered. Myelotoxicity imposes autologous stem cell rescue. European Group for Blood and Marrow Transplantation experience of this treatment in patients with high-grade glioma was reported here. A retrospective analysis of 217 patients from European Group for Blood and Marrow Transplantation database was realized. Ninety-six patients underwent complete surgical resection while the 121 others had partial resection or only biopsy and were evaluable for an antitumor effect. Patients received 800 mg/m2 of carmustine intravenously at least 1 month after neurosurgery. Forty-eight to 72 hr after chemotherapy, 108 patients received autologous hematopoietic stem cells from bone marrow harvest and 109 patients autologous hematopoietic stem cells from peripheral blood. Radiotherapy was started approximately 40 days after transplantation. Ten deaths were related to the treatment. Of the 121 patients evaluable for tumor response, 64 (53%) presented an objective response. This protocol appear feasible, but with toxicity-related mortality of 4.5%. Median overall survival was 20 months and median time to treatment failure was 7 months. Overall survival and time to treatment were correlated with age, quality of resection and histological subtypes. In glioblastoma multiforme, age and surgery quality appeared to be prognostic factors. Compared with Stupp et al.'s recent study, this study did not favor high-dose carmustine for patients with glioblastoma multiforme with complete surgical resection. 相似文献
993.
Humblot C Murkovic M Rigottier-Gois L Bensaada M Bouclet A Andrieux C Anba J Rabot S 《Carcinogenesis》2007,28(11):2419-2425
2-amino-3-methylimidazo[4,5-f]quinoline (IQ) is a genotoxic/carcinogenic compound formed in meat and fish during cooking. Following absorption in the upper part of the gastrointestinal tract, IQ is mainly metabolized in the liver by xenobiotic-metabolizing enzymes. Among them, UDP-glucuronosyl transferases lead to harmless glucuronidated derivatives that are partly excreted via the bile into the digestive lumen, where they come into contact with the resident microbiota. The purpose of this study is to investigate if microbial beta-glucuronidase could contribute to IQ genotoxicity by releasing reactive intermediates from IQ glucuronides. We constructed a beta-glucuronidase-deficient isogenic mutant from a wild-type Escherichia coli strain carrying the gene uidA encoding this enzyme and compared the genotoxicity of IQ in gnotobiotic rats monoassociated with the wild-type or the mutant strain. The Comet assay performed on colonocytes and hepatocytes showed that the presence of beta-glucuronidase in the digestive lumen dramatically increased (3-fold) the genotoxicity of IQ in the colon. This deleterious effect was paralleled by slight modifications of the pharmacokinetics of IQ. The urinary and faecal excretion of the parent compound and its conjugated derivatives reached a maximum 24-48 h after gavage in rats harbouring the beta-glucuronidase-deficient strain. In rats associated with the wild-type strain, the kinetics of urinary excretion showed a biphasic curve with a second, smaller peak after 144 h. This is the first in vivo demonstration that bacterial beta-glucuronidase plays a pivotal role in the genotoxicity of a common food-borne carcinogen. 相似文献
994.
Puyal J Sage C Demêmes D Dechesne CJ 《Brain research. Developmental brain research》2002,139(1):51-57
We investigated the distribution of the glutamate receptor subunits, alpha-amino-3-hydroxy-5-methyl-4 isoazolepropionic acid (AMPA) GluR2 and GluR2/R3, and N-methyl-D-aspartate (NMDA) NR1, and the timing of their appearance during early development of the mouse vestibular and spiral ganglia. NMDA NR1 was the first to be expressed, in the statoacoustic ganglion neurons on E11. GluR2/R3 immunoreactivity was detected in these neurons on E12. This signal probably corresponded exclusively to GluR3, as no signal was obtained for GluR2 alone at this stage. The appearance of these proteins began much earlier than previously reported. GluR2 staining was observed later, on E14 in the vestibular neurons and on E17 in the spiral neurons. The sequence in which these three glutamate receptors appeared suggested possible differences in their roles in the establishment of neuronal circuitry in the inner ear sensory epithelia. The production of NR1 and GluR2/R3 began during the early period of neuron growth and fasciculation. GluR2 appeared later and its expression paralleled synaptogenesis in the vestibular sensory epithelia and in the organ of Corti. 相似文献
995.
D Taussig G Dorfmüller M Fohlen C Jalin C Bulteau S Ferrand-Sorbets M Chipaux O Delalande 《Seizure》2012,21(8):631-638
PurposeIn children with drug-resistant focal epilepsy who are candidates for surgery, invasive exploration is sometimes required. However, this is being controversially discussed for children younger than 3 years. The question of its necessity, feasibility and its risks is often raised, since it concerns primarily lesional epilepsy and a lesionectomy might be proposed right away. However, this attitude does not take into account the specificities of epilepsy at this age, including poor specificity of electroclinical semiology and the ongoing myelination challenging the interpretation of magnetic resonance imaging (MRI).MethodsWe retrospectively studied the records of children with drug-resistant epilepsy who were younger than 3 years of age at the time of their invasive exploration at our institution from 2000 to 2009. We reviewed the clinical, imaging and electrophysiological data, and included post-operative outcome for those who underwent surgery.Key findings26 Children met the inclusion criteria. All had drug-resistant epilepsy that started at an average of 5.2 months (range 0–20 months) with multiple daily seizures in all and developmental delay in 16. The average age at the time of exploration was 21.8 months (range 5–35). In 20 children, subdural electrodes in combination with two or three depth electrodes were implanted, and in six children aged over 2 years a stereo-electro-encephalography (SEEG) was performed. SEEG was considered technically difficult to achieve before the age of 2 years. The tolerance of invasive exploration was good with a 3% morbidity consisting of one subdural hematoma during exploration by subdural electrodes, evacuated without any particular sequelae. In 25 patients, the exploration permitted to propose a focal resection. The surgical intervention was in the frontal lobe in 12 cases, the parietal lobe in six, the occipital lobe in two patients, and the temporal lobe in one child who underwent an additional resection. Four children had a resection of two or three lobes. Five underwent a second surgery, following a second invasive exploration. Histologically, the resected tissue revealed focal cortical dysplasia in 21 cases (including three patients with tuberous sclerosis), two post-ischemic lesions, one dysembryoplastic neuroepithelial tumor, and one gangliglioma associated with dysplasia. The mean postoperative follow-up period was 51 months (range 4–110). For the children operated on twice, follow-up was counted from the second surgery on. Seventeen children (68%) had an outcome of Engel class 1. In five (20%), seizure frequency was significantly improved (Engel class 3). In two of three patients without improvement in seizure frequency (Engel class 4), a new SEEG is planned and the third is presently a candidate for hemispherotomy.SignificanceInvasive exploration is feasible, well tolerated and carries a low morbidity in children under 3 years of age. At this age, it is indicated for drug-resistant lesional epilepsy associated with developmental delay. It permits delineating the lesion, which is not possible with MRI. The choice of the technique is in part age-dependent. The discussion of its indication arises in the same way as in the older child. 相似文献
996.
Roussin R Belli E Lacour-Gayet F Godart F Rey C Bruniaux J Planché C Serraf A 《The Journal of thoracic and cardiovascular surgery》2002,123(3):443-8; discussion 449-50
OBJECTIVE: The optimal technique for aortic arch reconstruction through median sternotomy is still under debate. We have introduced the technique of pulmonary autograft patch aortoplasty as a reliable alternative. METHODS: The outcomes of 51 infants who underwent neonatal repair of interrupted aortic arch (n = 28) or coarctation associated with ventricular septal defect (n = 23) since 1992 were analyzed. The patients were reviewed in three groups according to the aortic arch reconstruction technique: group I underwent direct anastomosis (n = 23), group II underwent homograft or pericardial patch aortoplasty (n = 8), and group III underwent pulmonary autograft patch aortoplasty (n = 20). The pulmonary autograft patch consisted in the anterior wall of the main pulmonary artery, between the supracommissural level and the divided ductus arteriosus. The created defect was replaced with fresh autologous pericardium. RESULTS: All patients except 1 were discharged without significant residual gradient at the level of the aortic arch. At a median delay of 7 months (range 2-51 months), 11 patients (22%) had recurrence of arch obstruction and underwent balloon angioplasty (n = 8) or surgical correction (n = 3). One patient who had undergone direct anastomosis required reoperation for bronchial compression. At a median follow-up of 29 months, the actuarial freedoms from recurrent arch obstruction were 81% for direct anastomosis, 28% for homograft or pericardial patch aortoplasty, and 100% for pulmonary autograft aortoplasty (P =.03 for group III vs group I and P <.0001 for group III vs group II). CONCLUSIONS: The aortic arch repair associated with pulmonary autograft patch augmentation resulted in superior midterm outcomes and therefore constitutes a reliable alternative to the direct anastomosis technique. It allowed complete relief of anatomic afterload and diminished the anastomotic tension, thus reducing the risk of restenosis and tracheobronchial compression. We observed a significantly higher rate of recurrence after patch aortoplasty with other materials. 相似文献
997.
Outcome of treatment in adults with acute lymphoblastic leukemia: analysis of the LALA-94 trial. 总被引:21,自引:0,他引:21
Xavier Thomas Jean-Michel Boiron Fran?oise Huguet Hervé Dombret Ken Bradstock Norbert Vey Tibor Kovacsovics André Delannoy Nathalie Fegueux Pierre Fenaux Aspasia Stamatoullas Jean-Paul Vernant Olivier Tournilhac Agnès Buzyn Oumedaly Reman Christiane Charrin Claude Boucheix Jean Gabert Véronique Lhéritier Denis Fiere 《Journal of clinical oncology》2004,22(20):4075-4086
PURPOSE: We analyzed the benefits of a risk-adapted postremission strategy in adult lymphoblastic leukemia (ALL), and re-evaluated stem-cell transplantation (SCT) for high-risk ALL. PATIENTS AND METHODS: A total of 922 adult patients entered onto the trial according to risk groups: standard-risk ALL (group 1), high-risk ALL (group 2), Philadelphia chromosome-positive ALL (group 3), and CNS-positive ALL (group 4). All received a standard four-drug/4-week induction course. Patients from group 1 who achieved a complete remission (CR) after one course of induction therapy were randomly assigned between intensive and less intensive postremission chemotherapy, whereas those who achieved CR after salvage therapy were then included in group 2. Patients in groups 2, 3, and 4 with an HLA-identical sibling were assigned to allogeneic SCT. In groups 3 and 4, autologous SCT was offered to all other patients, whereas in group 2 they were randomly assigned between chemotherapy and autologous SCT. RESULTS: Overall, 771 patients achieved CR (84%). Median disease-free survival (DFS) was 17.5 months, with 3-year DFS at 37%. In group 1, the 3-year DFS rate was 41%, with no difference between arms of postremission randomization. In groups 2 and 4, the 3-year DFS rates were 38% and 44%, respectively. In group 2, autologous SCT and chemotherapy resulted in comparable median DFS. Patients with an HLA-matched sibling (groups 2 and 4) had improved DFS. Three-year DFS was 24% in group 3. CONCLUSION: Allogeneic SCT improved DFS in high-risk ALL in the first CR. Autologous SCT did not confer a significant benefit over chemotherapy for high-risk ALL. 相似文献
998.
PURPOSE: To determine retrospectively the accuracy of screening ultrasonography (US) in patients with hypotension (systolic blood pressure or =2) (consensus by three readers) and were assigned to a low- or high-risk group according to the presence of hematuria and/or axial fracture on radiographs. Screening US results were compared with findings with the best available reference standard (computed tomography [CT]), repeat US, other diagnostic test, laparotomy, autopsy, clinical course). Data were compared by using chi(2) or Fisher exact test, depending on expected frequencies, with Bonferroni correction for multiple comparisons. Continuous variables were compared by using unpaired Student t test or Mann-Whitney U test, depending on data distribution. RESULTS: The study included 77 male and 51 female patients (mean age, 42 years). Sensitivity was 85% (44 of 52) for detection of any injuries, 97% (30 of 31) for surgical injuries (ie, injuries requiring surgery), and 100% (10 of 10) for fatal injuries. Specificity was 96% (73 of 76), 82% (80 of 97), and 69% (81 of 118), and accuracy was 91% (117 of 128), 86% (110 of 128), and 71% (91 of 128), for respective injury categories. One nonfatal surgical injury was missed in a high-risk patient. For each injury category, frequency of injury in patients with a fluid score of 2 or more was nine times that in patients with a score of 0 (P < .001 for all comparisons). Frequency of false-negative US findings in high-risk patients was eight times that in low-risk patients (P < .01). CONCLUSION: In patients who are hypotensive after blunt abdominal trauma and not hemodynamically stable enough to undergo diagnostic CT, negative US findings virtually exclude surgical injury, while positive US findings indicate surgical injury in 64% of cases. 相似文献
999.
Yves Rossetti Bruno Tadary Claude Prablanc 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1994,97(3):487-496
Encoding of visual target location in extrapersonal space requires convergence of at least three types of information: retinal signals, information about orbital eye positions, and the position of the head on the body. Since the position of gaze is the sum of the head position and the eye position, inaccuracy of spatial localization of the target may result from the sum of the corresponding three levels of errors: retina, ocular and head. In order to evaluate the possible errors evoked at each level, accuracy of target encoding was assessed through a motor response requiring subjects to point with the hand towards a target seen under foveal vision, eliminating the retinal source of error. Subjects had first to orient their head to one of three positions to the right (0, 40, 80°) and maintain this head position while orienting gaze and pointing to one of five target positions (0, 20, 40, 60, 80°). This resulted in 11 combinations of static head and eye positions, and corresponded to five different gaze eccentricities. The accuracy of target pointing was tested without vision of the moving hand. Six subjects were tested. No systematic bias in finger pointing was observed for eye positions ranging from 0 to 40° to the right or left within the orbit. However, the variability (as measured by a surface error) given by the scatter of hand pointing increased quadratically with eye eccentricity. A similar observation was made with the eye centreed and the head position ranging from 0 to 80°, although the surface error increased less steeply with eccentricity. Some interaction between eye and head eccentricity also contributed to the pointing error. These results suggest that pointing should be most accurate with a head displacement corresponding to 90% of the gaze eccentricity. These results explain the systematic hypometry of head orienting towards targets observed under natural conditions: thus the respective contribution of head and eye to gaze orientation might be determined in order to optimize accuracy of target encoding. 相似文献
1000.
Regulatory effects of macrolides on bacterial virulence: potential role as quorum-sensing inhibitors 总被引:5,自引:0,他引:5
Pseudomonas aeruginosa is an opportunistic pathogen, and this organism is a major cause of pulmonary damage and mortality in patients with cystic fibrosis (CF), diffuse panbronchiolitis (DPB) and other forms of bronchiectasis. A break-through in the treatment of DPB and associated chronic P. aeruginosa pulmonary infection was realized when a patient with DPB improved dramatically after treatment with erythromycin for years. Now, long-term macrolide therapy has become a first line of treatment in DPB patients, and the immunomodulatory properties have now been extended to other clinical settings, including CF. An important factor in the pathogenesis of chronic P. aeruginosa infection is a bacterial cell-to-cell signaling mechanism, referred to as "quorum sensing", which enables bacteria to coordinately turn on and off specific virulence genes through the production of autoinducer molecules. Interference or blocking of quorum-sensing systems has been considered an attractive therapeutic strategy. Clinical and basic science data suggests the potential of macrolides as relevant inhibitors of the Pseudomonas quorum-sensing system. In fact, certain macrolides strongly suppressed quorum-sensing associated genes and autoinducer production, in addition to inhibition of a variety of virulence factors. In this review, clinical efficacy of macrolides on DPB and CF patients will be briefly summarized. Additionally, the mechanisms of action of macrolides will be discussed from the standpoint of sub-MIC macrolide effects on P. aeruginosa, particularly the ability of this antibiotic to suppress quorum-sensing systems, which may be crucial in the pathogenesis of chronic P. aeruginosa infection. 相似文献