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1.
Urol Case Rep ; 40: 101894, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34712587

ABSTRACT

Although primarily a pediatric disease, nephroblastomas (also known as Wilms tumor) occur in adults at a rate of less than 0.2 cases per million per year. Rarer still are teratoid Wilms tumors, which arise from teratomas and therefore can be extrarenal. We describe the sixth recorded case of a testicular teratoid Wilms tumor in an adult patient with accompanying histological images of the specimen. Following the case, there is a brief discussion of the current literature.

2.
Rev Sci Instrum ; 89(7): 075105, 2018 Jul.
Article in English | MEDLINE | ID: mdl-30068093

ABSTRACT

We designed and built a mobile experimental set-up for studying the interaction of ion beams with solid samples in a wide temperature range from 9 to 300 K. It is either possible to mount up to three samples prepared ex situ or to prepare samples by condensation of molecules from gases or vapours onto IR or Visible-ultraviolet (Vis-UV) transparent windows. The physico-chemical evolution during irradiation can be followed in situ with different analysis techniques including Fourier transform infrared spectroscopy, Vis-UV, and quadrupole mass spectrometry.

3.
Rev Sci Instrum ; 82(10): 103301, 2011 Oct.
Article in English | MEDLINE | ID: mdl-22047285

ABSTRACT

We show that an x-ray charge coupled device (CCD) may be used as a particle detector for atomic and molecular mega-electron-volt (MeV) projectiles of around a few hundred keV per atomic mass unit. For atomic species, spectroscopic properties in kinetic energy measurements (i.e., linearity and energy resolution) are found to be close to those currently obtained with implanted or surface barrier silicon particle detectors. For molecular species, in order to increase the maximum kinetic energy detection limit, we propose to put a thin foil in front of the CCD. This foil breaks up the molecules into atoms and spreads the charges over many CCD pixels and therefore avoiding saturation effects. This opens new perspectives in high velocity molecular dissociation studies with accelerator facilities.

4.
Phys Rev Lett ; 104(4): 043401, 2010 Jan 29.
Article in English | MEDLINE | ID: mdl-20366708

ABSTRACT

The complete fragmentation of highly excited and multicharged C(n)(q+) clusters (n=5-10; q=2-4), produced in high velocity collisions of C(n)(+) with atoms, has been measured. Multiplicity distributions are presented and used to deduce, within a statistical framework, the partitioning of energy between the fragments' production and fragments' kinetic energy. This partitioning is found to scale as the charge over mass ratio of the cluster.

5.
J Chem Phys ; 128(12): 124312, 2008 Mar 28.
Article in English | MEDLINE | ID: mdl-18376924

ABSTRACT

We have measured fragmentation branching ratios of neutral C(n)H and C(n)H(+) cations produced in high velocity (4.5 a.u) collisions between incident C(n)H(+) cations and helium atoms. Electron capture gives rise to excited neutral species C(n)H and electronic excitation to excited cations C(n)H(+). Thanks to a dedicated setup, based on coincident detection of all fragments, the dissociations of the neutral and cationic parents were recorded separately and in a complete way. For the fragmentation of C(n)H, the H-loss channel is found to be dominant, as already observed by other authors. By contrast, the H-loss and C-loss channels equally dominate the two-fragment break up of C(n)H(+) species. For these cations, we provide the first fragmentation data (n>2). Results are also discussed in the context of astrochemistry.

6.
Phys Rev Lett ; 93(6): 063401, 2004 Aug 06.
Article in English | MEDLINE | ID: mdl-15323628

ABSTRACT

We present a combined experimental and theoretical study of fragmentation of small Cn clusters (n = 5,7,9) produced in charge transfer collisions of fast (nu = 2.6 a.u.) singly charged Cn+ clusters with He. Branching ratios for all possible fragmentation channels have been measured. Comparison with microcanonical Metropolis Monte Carlo simulations based on quantum chemistry calculations allows us to determine the energy distribution of the excited clusters just after the collision.

8.
J Spinal Disord ; 10(6): 467-72, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9438810

ABSTRACT

This study evaluated the use of recombinant human bone morphogenetic protein (rhBMP-2) with various types of carrier media, and the effect of rhBMP-2 as an adjunct to autogenous iliac crest bone graft in the canine spinal fusion model. BMP induces mesenchymal cells to differentiate into cartilage and bone. The recent availability of rhBMP-2 has created the opportunity to evaluate this material's properties in augmenting autogenous bone graft in spinal fusion. Currently, the most appropriate type of carrier media for rhBMP-2 is undetermined. Bilateral intertransverse spinal fusions were performed on six canine lumbar spines at L1-L2, L3-L4, and L5-L6, using autogenous posterior iliac crest bone graft at each level, creating a total of 18 segmental fusion sites. All 18 sites were then randomly assigned to one of six fusion methods: autogenous bone graft (ABG) alone, ABG + rhBMP-2, ABG + collagen (Helistat) "sandwich" + rhBMP-2, ABG + collagen (Helistat) morsels + rhBMP-2, ABG + polylactic/glycolic acid sponge (PLGA) sandwich + rhBMP-2, and ABG + open-pore polylactic acid morsels + rhBMP-2. Each material was evaluated for ease of handling and application at the index surgery. The animals underwent computed tomography (CT) scanning of the lumbar fusion sites after 8 weeks. Volumetric measurements of total fusion mass at each level were performed using two-dimensional CT scan slices and a volumetric program supplied by the Siemens Medical System. The animals were killed after imaging studies. The lumbar spine fusion sites were evaluated for integrity of the fusion mass, both visually and with manual mechanical stressing. Crossover of the fusion mass to adjoining levels was also evaluated. Histologic evaluation of all fusion sites was performed. The addition of rhBMP-2 significantly increased bone graft volume as noted on CT scan. Carrier that could be mixed with morselized bone graft offered easier handling and application and all spine segments fused. Polylactic/glycolic acid (PLGA) sites were associated with a greater incidence of voids within the fusion mass. No significant difference in carrier media for rhBMP-2 could be determined. However, PLGA was associated with a higher rate of fusion mass void formation. rhBMP-2, when added to autograft, significantly increased the volume and the maturity of the resulting fusion mass.


Subject(s)
Bone Morphogenetic Proteins/therapeutic use , Bone Transplantation , Osteogenesis/drug effects , Spinal Fusion , Transforming Growth Factor beta , Animals , Biocompatible Materials , Bone Morphogenetic Protein 2 , Cell Differentiation/drug effects , Collagen/administration & dosage , Dogs , Drug Carriers , Ilium/transplantation , Lactic Acid/administration & dosage , Mesoderm/drug effects , Polyglycolic Acid/administration & dosage , Polylactic Acid-Polyglycolic Acid Copolymer , Polymers/administration & dosage , Recombinant Proteins/therapeutic use , Surgical Sponges
9.
J Otolaryngol ; 25(2): 108-12, 1996 Apr.
Article in French | MEDLINE | ID: mdl-8683650

ABSTRACT

Branchial cysts located in the parapharyngeal space are extremely rare; only seven cases were described in the literature between 1927 and today. In Quebec City, two cases were operated on during the last 3 years. Often, many antibiotic and surgical treatments have been inefficiently used, before getting to the correct diagnosis and final curative treatment. We stress the importance of a detailed evaluation of the lesion and of a noninvasive surgery. Magnetic resonance imaging is the primary imaging modality for parapharyngeal space masses, and surgical excision using the transoral approach is advantageous in selected cases.


Subject(s)
Branchioma/surgery , Pharynx/surgery , Adolescent , Adult , Branchioma/diagnosis , Branchioma/physiopathology , Female , Humans , Magnetic Resonance Imaging , Pharynx/physiopathology , Tomography, X-Ray Computed
11.
Pediatr Cardiol ; 14(1): 9-12, 1993 Jan.
Article in English | MEDLINE | ID: mdl-8456034

ABSTRACT

Outcome in 81 pediatric patients with dilated cardiomyopathy was reviewed to assess whether treatment with angiotensin-converting enzyme (ACE) inhibitors affected survival. Age at onset was 3.6 +/- 0.6 years. Twenty-seven children (group 1) were treated with ACE inhibitors. Conventional therapy was used in the remaining 54 patients (group 2). There were no significant differences between the two groups in age at onset, left ventricular shortening fraction, left ventricular end-diastolic pressure, or mean pulmonary artery pressure. Patients treated with ACE inhibitors had a significantly better survival during the first year (p < 0.05) with continuation of this trend throughout the second year (p = 0.06). Beyond 2 years there was a tendency toward better survival in ACE inhibitor-treated patients, but the differences were no longer significant (p = 0.14). These data, along with observations in adult patients with chronic cardiac failure, indicate that converting enzyme inhibitors have a beneficial effect on prolonging survival of infants and children with severe left ventricular dysfunction from dilated cardiomyopathy.


Subject(s)
Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Cardiomyopathy, Dilated/drug therapy , Cardiomyopathy, Dilated/mortality , Captopril/therapeutic use , Child, Preschool , Enalapril/therapeutic use , Female , Humans , Life Tables , Male , Retrospective Studies , Survival Analysis , Time Factors
13.
Biochem J ; 286 ( Pt 3): 693-9, 1992 Sep 15.
Article in English | MEDLINE | ID: mdl-1417727

ABSTRACT

The turnover of choline-containing phosphoglycerides (PC) in response to agonist stimulation is well documented in human neutrophils. We have now compared the enzymic pathways of N-formylmethionyl-leucylphenylalanine (fMLP)-, A23187- and phorbol-12-myristate 13-acetate (PMA)-induced diglyceride (DG) and phosphatidic acid (PA) generation in these cells. In order to distinguish between phospholipase C- and D-mediated PC breakdown, human neutrophils were radiolabelled with 1-O-[3H]alkyl-2-acyl-glycero-3-phosphocholine and stimulated in the presence of ethanol or propranolol. The addition of 0.5% ethanol to the incubation mixture resulted in the production of phosphatidylethanol, indicative of phospholipase D activation, in response to all three stimuli. Concomitant with phosphatidylethanol formation was a partial block of PA production. The production of DG was also partially blocked by addition of ethanol. Propranolol (200 microM) was also used to assess the contributions of phospholipases C and D toward DG generation. Inhibition of PA phosphohydrolase by propranolol resulted in the complete abolition of DG generation when neutrophils were stimulated with fMLP. In contrast, propranolol only partially inhibited DG generation in response to A23187 and PMA. These results suggested that DG production in response to fMLP stimulation is mediated via the activation of phospholipase D, whereas A23187- or PMA-induced DG generation may involve more than one pathway. However, examination of the water-soluble choline metabolites produced indicated that phospholipase D was responsible for the production of PA and DG in response to all three stimuli.


Subject(s)
Calcimycin/pharmacology , Diglycerides/metabolism , Glycerophosphates/metabolism , N-Formylmethionine Leucyl-Phenylalanine/pharmacology , Neutrophils/metabolism , Tetradecanoylphorbol Acetate/pharmacology , Cells, Cultured , Choline/metabolism , Drug Interactions , Ethanol/pharmacology , Glycerophosphates/chemistry , Humans , Hydrolysis , Neutrophils/drug effects , Phospholipase D/metabolism , Propranolol/pharmacology , Type C Phospholipases/metabolism
14.
16.
Am J Cardiol ; 68(4): 365-9, 1991 Aug 01.
Article in English | MEDLINE | ID: mdl-1858677

ABSTRACT

A review of 81 infants and children with dilated, poorly contracting left ventricles without associated structural abnormalities was undertaken to identify risk factors for poor outcome, which could be used in selecting candidates for cardiac transplantation. Significant atrial or ventricular dysrhythmias, or both, were detected on presentation or during follow-up in 24 patients. Arrhythmias were present in only 8 of 51 survivors (16%) but were detected in 16 of 30 patients (53%) who died (p less than 0.05). Patients dying suddenly were even more likely to have had documented dysrhythmias (8 of 11, p less than 0.05). Left ventricular shortening fraction was similar in survivors and nonsurvivors (14.9 +/- 1.0% vs 15.3 +/- 1.7%). Left ventricular end-diastolic pressure in 44 patients who had cardiac catheterization averaged 20.8 +/- 1.6 mm Hg. Left ventricular end-diastolic pressure was significantly higher in patients who died than in those who survived (29.5 +/- 2.2 vs 15.0 +/- 1.6 mm Hg, p less than 0.001). Analysis of actuarial survival revealed that mortality was highest during the first 6 months after presentation (19% mortality). Survival declined more gradually thereafter and was 70% at 2 years, 64% at 5 years and 52% after 11.5 years. Age at initial presentation did not have any significant impact on survival. However, left ventricular end-diastolic pressure greater than 25 torr was associated with a significantly increased mortality rate (p less than 0.05). Early cardiac transplantation should be considered in patients with markedly elevated left ventricular end-diastolic pressure or complex atrial or ventricular arrhythmias.


Subject(s)
Cardiomyopathy, Dilated/mortality , Actuarial Analysis , Adolescent , Arrhythmias, Cardiac/complications , Blood Pressure , Cardiomyopathy, Dilated/complications , Cardiomyopathy, Dilated/drug therapy , Cardiomyopathy, Dilated/physiopathology , Child , Child, Preschool , Female , Follow-Up Studies , Humans , Infant , Infant, Newborn , Male , Prognosis , Risk Factors , Survival Rate , Ventricular Function, Left
17.
Cancer Res ; 50(22): 7174-8, 1990 Nov 15.
Article in English | MEDLINE | ID: mdl-2224852

ABSTRACT

The glycerolipids of most cells are characterized by a specific proportion of ether linkages at the sn-1 position of the glycerol backbone. A number of tumors are known to have altered concentrations of ether-linked lipids compared to normal tissues. However, no through examination of the ether-lipid content of human leukemia cells has been reported despite the importance of these lipids in normal leukocyte function. In the present study samples were obtained from adults with acute myelogenous leukemia (AML), chronic granulocytic leukemia in blast crisis, and acute lymphocytic leukemia and from healthy human donors. The cellular lipids were extracted, the individual phospholipid classes were isolated, lipid phosphorus content was determined, and the lipids were converted to diglyceride benzoate derivatives for separation and quantitation of the subclasses by high performance liquid chromatography. The data indicate that all the leukemic cells analyzed have an altered phospholipid composition compared to their respective normal leukocytes. Furthermore, among the AML patients both the percentage of the choline-containing phosphoglyceride fraction (PC) which is alkyl linked and the nmoles alkyl-PC/10(6) cells differ significantly by FAB subtype. A positive correlation between the levels of alkyl-PC and the degree of cellular differentiation is observed. Although no differences are observed between chronic granulocytic leukemia in blast crisis and AML lipids, the leukemic cells contain dramatically lower levels of alkyl-linked PC than do normal polymorphonuclear leukocytes. In contrast, no differences are observed between the alkyl-PC content of normal and leukemic lymphocytes. In light of the relations among ether-lipids, protein kinase C, and cell differentiation, these data suggest the ether-linked lipids are important in myeloid cell function and differentiation.


Subject(s)
Leukemia, Lymphoid/metabolism , Leukemia, Myeloid/metabolism , Neutrophils/chemistry , Phospholipid Ethers/analysis , Alkylation , Chromatography, High Pressure Liquid , Chromatography, Thin Layer , Humans , Leukemia, Myeloid/classification , Phosphatidylcholines/analysis , Phosphatidylethanolamines/metabolism , Phosphatidylinositols/analysis , Phosphatidylinositols/chemistry , Phospholipid Ethers/metabolism , Sphingomyelins/analysis , Sphingomyelins/metabolism , Tumor Cells, Cultured
18.
J Clin Endocrinol Metab ; 69(5): 1047-52, 1989 Nov.
Article in English | MEDLINE | ID: mdl-2529265

ABSTRACT

The combined infusion of [3H]dehydroepiandrosterone sulfate [( 3H]DS) and [14C]estrone (E1) for 6 h in four normal women in the follicular phase of the cycle demonstrated values of 13.77 +/- 0.27 L/day (mean +/- SE) for the DS MCR (MCRDS) and 1343 +/- 206 L/day for MCRE1. The fraction of DS metabolized to dehydroepiandrosterone (D), [rho]DS-D, was 0.285 +/- 0.044, and the fraction of D arising from DS (delta D) was 0.318 +/- 0.096, determined using isotopic techniques. Raising the plasma DS concentration by 8.6 micrograms/mL (23 mumol/L) by infusing DS iv increased the MCRDS to 24.49 L/day in the first subject, and raising the plasma DS by 11.40 +/- 0.33 micrograms/mL (30.94 +/- 0.90 mumol/L) in the next three subjects raised the MCRDS to 35.7 +/- 1.3 L/day (P less than 0.01) without changing the MCRE1. The increase in MCRDS produced by increasing plasma DS makes it difficult to accurately measure the MCRDS in effect at the subject's endogenous plasma DS concentration by infusion of nonisotopic DS. Determination of the fractions of D, androstenedione (delta delta 4A), and testosterone (T) arising from DS using the increase in the plasma concentrations of these steroids produced by infusion of nonisotopic DS gave the following estimates: delta D = 0.262 +/- 0.042, delta delta 4A = 0.089 +/- 0.046, and delta T = 0.273 +/- 0.14.


Subject(s)
Androstenedione/biosynthesis , Dehydroepiandrosterone/analogs & derivatives , Dehydroepiandrosterone/biosynthesis , Dihydrotestosterone/blood , Testosterone/biosynthesis , Adult , Androstenedione/blood , Dehydroepiandrosterone/administration & dosage , Dehydroepiandrosterone/blood , Dehydroepiandrosterone/pharmacokinetics , Dehydroepiandrosterone Sulfate , Dose-Response Relationship, Drug , Estrone/administration & dosage , Female , Follicular Phase , Humans , Mathematics , Metabolic Clearance Rate , Radioimmunoassay , Testosterone/blood
19.
Cancer Res ; 49(16): 4441-5, 1989 Aug 15.
Article in English | MEDLINE | ID: mdl-2743333

ABSTRACT

A number of synthetic ether-linked phospholipids are selectively cytotoxic to neoplastic cells. However, the mechanisms underlying this selective cytotoxicity are not known. We have investigated the ether-lipid content of HL-60 and K562 human leukemia cells in relation to their sensitivity to 1-O-alkyl-2-O-methyl-rac-glycero-3-phosphocholine (ET-18-OCH3). HL-60 cells are much more sensitive than K562 cells to the cytotoxic effects of ET-18-OCH3 and, at the same time, they contain nearly twice as much ether lipid as the more resistant K562 cells. These observations suggested a relation between the cellular ether-lipid content and sensitivity to ET-18-OCH3. Further evidence linking these properties was obtained when the ether-lipid content of K562 cells was increased by incubating them in medium containing 1-O-hexadecyl-sn-glycerol. This supplementation not only increased the ether-lipid content of the cells but also increased their sensitivity to ET-18-OCH3. The 50% inhibitory concentration for ET-18-OCH3 decreased from 18.4 microM in the control cells to 9.83 microM in the supplemented cells.


Subject(s)
Antineoplastic Agents/metabolism , Leukemia/metabolism , Phospholipid Ethers/analysis , Phospholipid Ethers/metabolism , Antineoplastic Agents/classification , Drug Screening Assays, Antitumor , Humans , Leukemia/drug therapy , Membrane Lipids/classification , Membrane Lipids/metabolism , Phospholipid Ethers/classification , Tumor Cells, Cultured/drug effects , Tumor Cells, Cultured/metabolism
20.
FEBS Lett ; 250(2): 341-4, 1989 Jul 03.
Article in English | MEDLINE | ID: mdl-2546802

ABSTRACT

Human neutrophils incorporate and metabolize platelet-activating factor (PAF). We dissociated these events from PAF binding to its receptors. Cells were pretreated with either pronase, a PAF antagonist (L652731), or excess PAF. This reduced PAF receptor numbers by 70 to almost 100% but had no comparable effect upon the neutrophil's ability to metabolize PAF. Furthermore, HL-60 cells efficiently metabolized, but did not specifically bind, PAF. Thus, PAF receptor availability did not correlate with PAF metabolic capacity and we conclude that myelogenous tissues can process this bioactive ligand by a receptor-independent pathway.


Subject(s)
Platelet Activating Factor/metabolism , Platelet Membrane Glycoproteins , Receptors, Cell Surface/metabolism , Receptors, G-Protein-Coupled , Humans , Neutrophils/metabolism , Tumor Cells, Cultured
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