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91.
Cytotoxic Effect of Brain Macrophages on Developing 总被引:3,自引:0,他引:3
Brain macrophages are transiently present in different regions of the central nervous system during development or in the course of tissue remodelling following various types of injuries. To investigate the influence of these phagocytes on neuronal growth and survival, brain macrophages stemming from the cerebral cortex of rat embryos were added to neuronal primary cultures. A neurotoxic effect of brain macrophages was demonstrated by the reduction of the number of neurons bearing neurites within two days of contact between the two cell types. Neuronal death and phagocytosis were also directly observed in video recordings of living cultures. This toxicity involved the production by brain macrophages of reactive oxygen intermediates, as shown by the protective effect of catalase, a scavenger of H2O2. In addition, the respiratory bursts of brain macrophages were stimulated in the presence of neurons. These results suggest that brain macrophages could favour the appearance of neuroregressive events which occur either during neurogenesis or in neurodegenerative diseases, implying intracerebral recruitment of mononuclear phagocytes. 相似文献
92.
Pignatelli Brigitte; Bereziat Jean-Claude; Descotes Gerard; Bartsch Helmut 《Carcinogenesis》1982,3(9):1045-1049
Measurements were made of the effects of phenolic compounds,some of which are present in the human diet, on the nitrosationof proline by nitrite to give N-nitrosoproline (NPRO). In vitro,resorcinol, catechin, p-nitrosophenol and phenol were catalystsand chlorogenic acid an inhibitor; guaiacol showed a marginalcatalytic effect. Both the catalytic and the inhibiting effectswere dependent on pH and on the concentration of phenolic compounds;catalysis by resorcinol and catechin was increased at optimalratios of [nitrite]: [phenolic compound]. Endogenous nitrosationwas examined in vivo by co-administration of nitrite, prolineand a phenolic compound to rats and by monitoring the amountof NPRO excreted in the urine. Under similar experimental conditions,the catalytic effects observed in vivo decreased in the sameorder as those observed in vitro: resorcinol > p-nitrosophenol> catechin > phenol guaiacol; chlorogenic acid acted asan inhibitor. Catalysis and inhibition of N-nitrosation in ratsin vivo appears to occur via mechanisms similar to those invitro, although the effects in vivo were smaller. The implicationsof our findings for the endogenous formation of N-nitroso compoundsand for variations in exposure due to different dietary constituentsin humans are discussed. 相似文献
93.
M. Petschler M. Stiller B. Hoffmeister R. Witkowski C. Opitz J. S. Bill H. Peters 《Mund-, Kiefer- und Gesichtschirurgie》2003,1(1):83-87
Hintergrund
Cherubismus ist eine seltene genetisch bedingte Erkrankung der Knochen, die fast ausschlie?lich den Ober- und Unterkiefer betrifft. 相似文献94.
Youdas JW Atwood AL Harris-Love MO Stiller TL Egan KS Therneau TM 《The Journal of orthopaedic and sports physical therapy》2000,30(5):279-286
STUDY DESIGN: Repeated measures of 14 temporal factors of gait obtained with a multimemory stopwatch from a variety of subjects with locomotor impairments. OBJECTIVES: To estimate the intratester and intertester reliability of 14 temporal factors of gait by using a multimemory stopwatch; to compare novice and expert clinicians at mastery of making these temporal measurements. BACKGROUND: Temporal gait measures are useful for describing the effectiveness of treatment interventions in patients with locomotor impairments. METHODS AND MEASURES: Eleven adult subjects (mean age, 48.4 years; SD, 5.7 years), 10 with locomotor impairments and 1 elderly adult, ambulated along a 6-m walkway 3 times at a self-selected walking speed. The subjects were videotaped from the side as they walked. Four physical therapists independently analyzed the videotapes on 2 occasions; 2 examiners were recent graduates, and 2 others had 23 years of clinical experience. Intraclass correlation coefficients were used to estimate intratester reliability. A component of variance analysis quantified the sources of variation. RESULTS: Intraclass correlation coefficients for each of the 14 variables varied from 0.88 to 0.98. The major contributor to variance was subject, followed by trial, error, and tester; the tester factor generally contributed less than 1% to the total variance. CONCLUSIONS: Reliable measurements of the temporal aspects of gait can be made by using a multimemory stopwatch and videotape in a clinical setting on patients with various locomotor problems. Our data suggest that measurements obtained by more experienced physical therapists were no more reliable than those made by recent graduates. 相似文献
95.
Regine Schneider-Stock Carsten Boltze Jerzy Lasota Markku Miettinen Brigitte Peters Matthias Pross Albert Roessner Thomas Günther 《Journal of clinical oncology》2003,21(9):1688-1697
PURPOSE: Gastrointestinal stromal tumors (GISTs) represent a distinctive (but histologically heterogeneous) group of neoplasms, the malignant potential of which is often uncertain. To determine the prognostic relevance of p16INK4 alterations in GISTs, we investigated a larger group of GISTs and correlated the genetic findings with clinicopathological factors and patient survival. MATERIAL AND METHODS: We evaluated the methylation status of the promotor by methylation-specific polymerase chain reaction (PCR), the presence of mutations by PCR-SSCP-sequencing, the loss of heterozygosity at the p16INK4 locus (using the c5.1 marker), and the immunohistochemical expression of p16INK4 protein in 43 GISTs in 39 patients. RESULTS: p16INK4 alterations were found in 25 of 43 GISTs (58.1%), with benign, borderline, or malignant GISTs showing no differences in the type and frequency of alteration. p16INK4 alterations were correlated with a loss of p16INK4 protein expression (P <.01). Patients who had tumors with p16INK4 alterations had a poorer prognosis than patients with tumors without such alterations (P =.02). There was a high predictive value for p16INK4 alterations only in the group of benign and borderline GISTs (P <.01) with regard to clinical outcome. Univariate Cox's proportional hazard regression analysis revealed a strong correlation between p16INK4 alterations, tumor size, mitotic index, and overall survival (P <.02), whereas multivariate Cox's analysis confirmed only p16INK4 alterations as an independent prognostic factor. CONCLUSION: We believe that the evaluation of p16INK4 alteration status is a helpful prognosticator, particularly in the benign and borderline groups of GISTs. 相似文献
96.
Phase I trial and pharmacokinetic study of BMS-247550, an epothilone B analog, administered intravenously on a daily schedule for five days. 总被引:4,自引:0,他引:4
Jame Abraham Manish Agrawal Susan Bakke Ann Rutt Maureen Edgerly Frank M Balis Brigitte Widemann Louis Davis Bharat Damle Daryl Sonnichsen David Lebwohl Susan Bates Herb Kotz Tito Fojo 《Journal of clinical oncology》2003,21(9):1866-1873
PURPOSE: The epothilones are a novel class of nontaxane microtubule-stabilizing agents. BMS-247550 is a semisynthetic analog of the natural product epothilone B. We conducted a phase I study administering BMS-247550 as a 1-hour intravenous infusion daily for 5 consecutive days every 21 days. PATIENTS AND METHODS: Twenty-one patients received BMS-247550 without filgrastim in the first cycle. An additional six patients were enrolled at a starting dose of 8 mg/m2/d with filgrastim support. Twenty-one of the 27 patients had received prior paclitaxel, docetaxel, or both. RESULTS: One hundred seven cycles were administered to 27 patients. The maximum-tolerated dose was 6 mg/m2 of BMS-247550 administered as a 1-hour intravenous infusion daily for 5 consecutive days every 21 days. Dose-limiting toxicity at a dose of 8 mg/m2/d was neutropenia with or without filgrastim support. Nonhematologic grade 3 toxicities included fatigue (seven cycles), stomatitis (two cycles), and anorexia (one cycle). The mean terminal half-life of BMS-247550 was 16.8 +/- 6.0 hours, the volume of distribution at steady-state was 798 +/- 375 L, and the clearance was 712 +/- 247 mL/min. Objective responses were observed in patients with breast, cervical, and basal cell cancer. Reductions in CA-125 levels were noted in patients with ovarian cancer. CONCLUSION: The recommended phase II dose of BMS-247550 on the daily schedule for 5 days is 6 mg/m2/d. Neutropenia was dose limiting, but higher doses were tolerated by a large fraction of patients with filgrastim support. Peripheral neuropathy was mild, even after multiple cycles of therapy, and was not dose limiting. 相似文献
97.
Torsten Haferlach Claudia Schoch Helmut L?ffler Winfried Gassmann Wolfgang Kern Susanne Schnittger Christa Fonatsch Wolf-Dieter Ludwig Christian Wuchter Brigitte Schlegelberger Peter Staib Albrecht Reichle Uschi Kubica Hartmut Eimermacher Leopold Balleisen Andreas Grüneisen Detlef Haase Carlo Aul Jochen Karow Eva Lengfelder Bernhard W?rmann Achim Heinecke Maria Cristina Sauerland Thomas Büchner Wolfgang Hiddemann 《Journal of clinical oncology》2003,21(2):256-265
PURPOSE: On the basis of cytomorphology according to the French-American-British (FAB) classification, we evaluated the prognostic impact of dysplastic features and other parameters in de novo acute myeloid leukemia (AML). We also assessed the clinical significance of the recently introduced World Health Organization (WHO) classification for AML, which proposed dysplasia as a new parameter for classification. PATIENTS AND METHODS: We analyzed prospectively 614 patients with de novo AML, all of whom were diagnosed by central morphologic analysis and treated within the German AML Cooperative Group (AMLCG)-92 or the AMLCG-acute promyalocytic leukemia study. RESULTS: Patients with AML M3, M3v, or M4eo demonstrated a better outcome compared with all other FAB subtypes (P <.001); no prognostic difference was observed among other FAB subtypes. The presence or absence of dysplasia failed to demonstrate prognostic relevance. Other prognostic markers, such as age, cytogenetics, presence of Auer rods, and lactate dehydrogenase (LDH) level at diagnosis, all showed significant impact on overall and event-free survival in univariate analyses (P <.001 for all parameters tested). However, in a multivariate analysis, only cytogenetics (unfavorable or favorable), age, and high LDH maintained their prognostic impact. Dysplasia was not found to be an independent prognostic parameter, but the detection of trilineage dysplasia correlated with unfavorable cytogenetics. CONCLUSION: Our results indicate that cytomorphology and classification according to FAB criteria are still necessary for the diagnosis of AML but have no relevance for prognosis in addition to cytogenetics. Our results suggest that the WHO classification should be further developed by using cytogenetics as the main determinant of biology. Dysplastic features, in particular, have no additional impact on predicting prognosis when cytogenetics are taken into account. 相似文献
98.
Florence Perillat-Menegaux Jacqueline Clavel Marie-Fran?oise Auclerc André Baruchel Guy Leverger Brigitte Nelken No?l Philippe Danièle Sommelet Etienne Vilmer Denis Hémon 《Cancer epidemiology, biomarkers & prevention》2003,12(1):60-63
The association between a familial history of autoimmune disease and childhood acute leukemia was investigated in a French case-control study that, overall, was designed to assess the role of perinatal, infectious, environmental, and genetic factors in the etiology of childhood acute leukemia. Familial histories of autoimmune disease in first- and second-degree relatives were compared in 279 incident cases, 240 cases of acute lymphocytic leukemia (ALL) and 39 cases of acute non-lymphoblastic leukemia (ANLL), and 285 controls. Recruitment was frequency matched by age, gender, hospital, and ethnic origin. Odds ratios (OR) were estimated using an unconditional regression model taking into account the stratification variables, socioeconomic status, and familial structure. A statistically significant association between a history of autoimmune disease in first- or second-degree relatives and ALL (OR, 1.7; 95% confidence interval (CI), 1.0-2.8) was found. A relationship between thyroid diseases overall and ALL (OR, 2.0; 95% CI, 1.0-3.9) was observed. This association was more pronounced for potentially autoimmune thyroid diseases (Grave's disease and/or hyperthyroidism and Hashimoto's disease and/or hypothyroidism) (OR, 3.5; 95% CI, 1.1-10.7 and OR, 5.6; 95% CI, 1.0-31.1, respectively for ALL and ANLL), whereas it was not statistically significant for the other thyroid diseases (thyroid goiter, thyroid nodule, and unspecified thyroid disorders) (OR, 1.6; 95% CI, 0.7-3.5 and OR, 1.3; 95% CI, 0.2-7.0, respectively, for ALL and ANLL). The results suggest that a familial history of autoimmune thyroid disease may be associated with childhood acute leukemia. 相似文献
99.
100.
Leticia Duart-Castells Lídia Cantacorps Raúl Lpez-Arnau Sandra Montagud-Romero Brigitte Puster Paula Mera Dolors Serra Jorge Camarasa David Pubill Olga Valverde Elena Escubedo 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2021,24(1):77
BackgroundPrenatal alcohol exposure is a leading cause of neurobehavioral and neurocognitive deficits collectively known as fetal alcohol spectrum disorders, including eating disorders and increased risk for substance abuse as very common issues. In this context, the present study aimed to assess the interaction between prenatal and lactation alcohol exposure (PLAE) and a high-fat diet (HFD) during childhood and adolescence.MethodsPregnant C57BL/6 mice underwent a procedure for alcohol binge drinking during gestation and lactation periods. Subsequently, PLAE female offspring were fed with an HFD for 8 weeks, and thereafter, nutrition-related parameters as well as their response to cocaine were assessed.ResultsIn our model, feeding young females with an HFD increased their triglyceride blood levels but did not induce overweight compared with those fed with a standard diet. Moreover, PLAE affected how females responded to the fatty diet as they consumed less food than water-exposed offspring, consistent with a lower gain of body weight. HFD increased the psychostimulant effects of cocaine. Surprisingly, PLAE reduced the locomotor responses to cocaine without modifying cocaine-induced reward. Moreover, PLAE prevented the striatal overexpression of cannabinoid 1 receptors induced by an HFD and induced an alteration of myelin damage biomarker in the prefrontal cortex, an effect that was mitigated by an HFD-based feeding.ConclusionTherefore, in female offspring, some effects triggered by one of these factors, PLAE or an HFD, were blunted by the other, suggesting a close interaction between the involved mechanisms. 相似文献