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991.
RMi Targhetta Jean-Marie Bourgeois Roseline Chavagneux Estelle Coste Dominique Amy Pierre Balmes Landre Pourcelot 《Journal of clinical ultrasound : JCU》1993,21(4):245-250
Ultrasonography is considered to have limited application in respiratory diseases because air reflects sound waves. Twenty-four patients with radiologically confirmed pneumothorax and 100 healthy subjects underwent sonography. In all normal subjects, the hyperechoic pulmonary interface showed respiratory motions termed the “gliding sign” with some comet-tail artifacts. Sonographic signs were shown in all pneumothoraces: disappearance of the gliding sign and no comet tails. The extent of collapse cannot be evaluated, but it is possible to determine its area in partial pneumothorax (N = 5). The follow-up (N = 8) showed the reappearance of the gliding sign. Ultrasonography may be helpful in diagnosing pneumothorax in certain cases. © 1993 John Wiley & Sons, Inc. 相似文献
992.
Van Looy S Verplancke T Benoit D Hoste E Van Maele G De Turck F Decruyenaere J 《Critical care (London, England)》2007,11(4):R83
Introduction
Tacrolimus is an important immunosuppressive drug for organ transplantation patients. It has a narrow therapeutic range, toxic side effects, and a blood concentration with wide intra- and interindividual variability. Hence, it is of the utmost importance to monitor tacrolimus blood concentration, thereby ensuring clinical effect and avoiding toxic side effects. Prediction models for tacrolimus blood concentration can improve clinical care by optimizing monitoring of these concentrations, especially in the initial phase after transplantation during intensive care unit (ICU) stay. This is the first study in the ICU in which support vector machines, as a new data modeling technique, are investigated and tested in their prediction capabilities of tacrolimus blood concentration. Linear support vector regression (SVR) and nonlinear radial basis function (RBF) SVR are compared with multiple linear regression (MLR). 相似文献993.
Danet GH Pan Y Luongo JL Bonnet DA Simon MC 《The Journal of clinical investigation》2003,112(1):126-135
It has been proposed that bone marrow (BM) hematopoietic stem and progenitor cells are distributed along an oxygen (O2) gradient, where stem cells reside in the most hypoxic areas and proliferating progenitors are found in O2-rich areas. However, the effects of hypoxia on human hematopoietic stem cells (HSCs) have not been characterized. Our objective was to evaluate the functional and molecular responses of human BM progenitors and stem cells to hypoxic conditions. BM lineage-negative (Lin-) CD34+CD38- cells were cultured in serum-free medium under 1.5% O2 (hypoxia) or 20% O2 (normoxia) for 4 days. Using limiting dilution analysis, we demonstrate that the absolute number of SCID-repopulating cells (SRCs) increased by 5.8-fold in hypoxic cultures compared with normoxia, and by 4.2-fold compared with freshly isolated Lin-CD34+CD38- cells. The observed increase in BM-repopulating activity was associated with a preferential expansion of Lin-CD34+CD38- cells. We also demonstrate that, in response to hypoxia, hypoxia-inducible factor-1alpha protein was stabilized, surface expression of angiogenic receptors was upregulated, and VEGF secretion increased in BM Lin-CD34+ cultures. The use of low O2 levels to enhance the survival and/or self-renewal of human BM HSCs in vitro represents an important advance and could have valuable clinical implications. 相似文献
994.
Peroxynitrite-induced mitochondrial and endonuclease-mediated nuclear DNA damage in acetaminophen hepatotoxicity 总被引:3,自引:0,他引:3
Cover C Mansouri A Knight TR Bajt ML Lemasters JJ Pessayre D Jaeschke H 《The Journal of pharmacology and experimental therapeutics》2005,315(2):879-887
Intracellular sources of peroxynitrite formation and potential targets for this powerful oxidant and nitrating agent have not been identified after acetaminophen (AAP) overdose. Therefore, we tested the hypothesis that peroxynitrite generated in mitochondria may be responsible for mitochondrial DNA (mtDNA) and nuclear DNA (nDNA) damage. C3Heb/FeJ mice were treated with 300 mg/kg AAP and monitored for up to 12 h. Loss of mtDNA (assayed by slot blot hybridization) and substantial nDNA fragmentation (evaluated by anti-histone enzyme-linked immunosorbent assay, terminal deoxynucleotidyl transferase dUTP nick-end labeling assay, and agarose gel electrophoresis) were observed as early as 3 h after AAP overdose. Analysis of nitrotyrosine protein adducts in subcellular fractions established that peroxynitrite was generated predominantly in mitochondria beginning at 1 h after AAP injection. Delayed treatment with a bolus dose of glutathione (GSH) accelerated the recovery of mitochondrial glutathione, which then effectively scavenged peroxynitrite. However, mtDNA loss was only partially prevented. Despite the absence of nitrotyrosine adducts in the nucleus after AAP overdose, nDNA damage was almost completely eliminated with GSH administration. A direct comparison of nDNA damage after AAP overdose with nDNA fragmentation during tumor necrosis factor receptor-mediated apoptosis showed similar DNA ladders on agarose gels but quantitatively different results in three other assays. We conclude that peroxynitrite may be partially responsible for mtDNA loss but is not directly involved in nDNA damage. In contrast, nDNA fragmentation after AAP overdose is not caused by caspase-activated DNase but most likely by other intracellular DNase(s), whose activation is dependent on the mitochondrial oxidant stress and peroxynitrite formation. 相似文献
995.
Arnault TauziedeEspariat Batrice Parfait Aurore Besnard Joëlle Lacombe Johan Pallud Sanaa Tazi Stphanie Puget Guillaume Lot Benoît Terris Joëlle Cohen Michel Vidaud Dominique FigarellaBranger Franck Monnien Marc Polivka Homa AdleBiassette Pascale Varlet 《Brain pathology (Zurich, Switzerland)》2018,28(4):466-474
Clear cell meningioma (CCM) is a rare grade II histopathological subtype that usually occurs in young patients and displays high recurrence rate. Germline SMARCE1 mutations have been described in hereditary forms of this disease and more recently in small syndromic and sporadic CCM series. The diagnostic value of SMARCE1 in distinguishing between CCM and other meningioma variants has not been yet established. The aim of our study was to investigate the status of SMARCE1 in a series of CCMs and its morphological mimickers. We compared the performance of an anti‐SMARCE1 antibody and the molecular analysis of the SMARCE1 gene in a retrospective multicenter series of CCMs. All CCMs lossed SMARCE1 immunoexpression. Bi‐allelic inactivating events were found by NGS‐based sequencing in all of these cases, except for one, which was incompletely explored, but had a wild‐type sequence. We then validated the anti‐SMARCE1 antibody specificity by analyzing additional 305 pediatric and adult meningiomas of various subtypes and 15 non‐meningioma clear cell tumors by SMARCE1 immunohistochemistry. A nuclear immunostaining was preserved in all other meningioma variants, as well as non‐meningioma clear cell tumors. In conclusion, our series showed, for the first time, that SMARCE1 immunostaining is a highly sensitive biomarker for CCM, useful as a routine diagnostic biomarker. 相似文献
996.
Lacroix D Klug D Marquié C Kouakam C Grandmougin D Kacet S 《Pacing and clinical electrophysiology : PACE》2002,25(11):1561-1570
VT late after myocardial infarction usually originates from the endocardial surface; subepicardial substrates are also possible. The identification of these atypical locations with endocardial mapping remains unresolved even with new mapping technologies. This study compared isopotential maps, signal morphology, and activation patterns around left endocardial breakthroughs recorded in VTs originating from the subepicardium or subendocardium after remote myocardial infarction. These results were extracted from a database of 111 tachycardias obtained at surgery in 34 patients. Mapping was performed with a 128-unipolar electrode system using an epicardial mesh and a left ventricular endocardial balloon. Subepicardial (n = 7) and subendocardial VTs (n = 10) were defined as complete superficial reentry and/or as tachycardias with a > or = 25-ms delay between the earliest activity and the breakthrough of activation on the opposite surface. A positive potential distribution covering the area of initial endocardial activity was observed in a single subepicardial VT but in none of the subendocardial ones (P = NS). R waves were observed on the earliest endocardial unipolar signals in two subepicardial VTs and five subendocardial VTs (P = NS). The area covered by the first 5-ms or 10-ms isochrone at the endocardial level was larger in subepicardial VTs than in subendocardial VTs but the difference was not significant. In conclusion, despite a wider endocardial area of early activity in VTs of subepicardial origin, no reliable criteria can be proposed to identify these tachycardias from mapping data restricted to the endocardial surface. This is probably due to highly nonuniform anisotropic propagation around the scarred tissue. 相似文献
997.
998.
André M Baudoux E Bron D Canon JL D'Hondt V Fassotte MF D'Hondt L Fillet G Humblet Y Jerusalem G Vermeulen P Symann M Beguin Y 《Transfusion》2003,43(1):50-57
BACKGROUND: It is not known whether increasing the dose of filgrastim after mobilizing chemotherapy improves collection of peripheral blood progenitor cells (PBPC) and leads to faster hematopoietic engraftment after autologous transplantation. STUDY DESIGN AND METHODS: A randomized, open-label, multicenter trial was carried out in patients with breast cancer, multiple myeloma, and lymphoma, in which patients were randomized to receive 5 or 10 microg per kg per day of filgrastim after standard chemotherapy to mobilize PBPCs. After high-dose chemotherapy, the components from the first two leukapheresis procedures were returned, and all patients received 5 microg per kg day of filgrastim after transplantation. RESULTS: A total of 131 patients were randomized, of whom 128 were mobilized (Group A, 5 microg/kg, n = 66; Group B, 10 microg/kg, n = 62) and 112 were transplanted. Only six patients were not transplanted because of insufficient CD34+ cell numbers. The median number of CD34+ cells collected in the first two leukapheresis procedures tended to be higher in Group B than in Group A (12.0 vs. 7.2 x 10(6)/kg, NS), but after transplantation there was no significant difference in median times to platelet (9 days in both groups) or neutrophil (8 days in both groups) engraftment or the number of platelet transfusions (three in both groups). A subsequent subgroup analysis separating patients transplanted after first- or second-line chemotherapy also showed no measurable impact of filgrastim dose on the median CD34+ cell yield or on platelet engraftment in either subgroup. CONCLUSION: PBPC mobilization with chemotherapy and 5 microg per kg of filgrastim is very efficient, and 10 microg per kg of filgrastim does not provide additional clinical benefit. 相似文献
999.
Iris Noordman Anthonie Duijnhouwer Livia Kapusta Marlies Kempers Nel Roeleveld Michiel Schokking Dominique Smeets Kim Freriks Henri Timmers Janiëlle van Alfen-van der Velden 《European journal of medical genetics》2018,61(6):301-306
Introduction
Turner syndrome (TS) is a genetic disorder characterized by the (partial) absence or a structural aberration of the second sex chromosome and is associated with a variety of phenotypes with specific physical features and cardio-aortic malformations. The objective of this study was to gain a better insight into the differences in dysmorphic features between girls and women with TS and to explore the association between these features, karyotype and cardio-aortic malformations.Methods
This prospective study investigated 14 dysmorphic features of TS girls and women using a checklist. Three major phenotypic patterns were recognized (severe phenotype, lymphatic phenotype and skeletal phenotype). Patient data including karyotype and cardio-aortic malformations (bicuspid aortic valve (BAV) and aortic coarctation (COA)) were collected. Associations between the prevalence of dysmorphic features, karyotype and cardio-aortic malformations were analysed using chi2-test and odds ratios.Results
A total of 202 patients (84 girls and 118 women) were analysed prospectively. Differences in prevalence of dysmorphic features were found between girls and women. A strong association was found between monosomy 45,X and the phenotypic patterns. Furthermore, an association was found between COA and lymphatic phenotype, but no association was found between karyotype and cardio-aortic malformations.Conclusion
This study uncovered a difference in dysmorphic features between girls and women. Monosomy 45,X is associated with a more severe phenotype, lymphatic phenotype and skeletal phenotype. All patients with TS should be screened for cardio-aortic malformations, because in contrast to previous reports, karyotype and cardio-aortic malformations showed no significant association. 相似文献1000.
Crossover sexual offenses are defined as those in which victims are from multiple age, gender, and relationship categories. This study investigates admissions of crossover sexual offending from sex offenders participating in treatment who received polygraph testing. For 223 incarcerated and 266 paroled sexual offenders, sexual offenses were recorded from criminal history records and admissions during treatment coupled with polygraph testing. The majority of incarcerated offenders admitted to sexually assaulting both children and adults from multiple relationship types. In addition, there was a substantial increase in offenders admitting to sexually assaulting victims from both genders. In a group of incarcerated offenders who sexually assaulted children, the majority of offenders admitted to sexually assaulting both relatives and nonrelatives, and there was a substantial increase in the offenders admitting to assaulting both male and female children. Although similar trends were observed for the sample of parolees, the rates were far less dramatic. Parolees appeared to have greater levels of denial, had participated in fewer treatment sessions, and perceived greater supervision restrictions as a result of admitting additional offenses. These findings support previous research indicating that many sexual offenders do not exclusively offend against a preferred victim type. 相似文献