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Biomedical subjects

J Fleury

Publications and source records attributed to J Fleury.

At least 91 records · Page 5Linked to original sources

Yawning: a possible confounding variable in EMG biofeedback studies.

An elderly hemiplegic patient participating in an EMG biofeedback training program was observed to produce a synergistic flexion movement of the plegic (determined by functional evaluations) upper limb while yawning. In the course of the training sessions the electrical activity of the anterior deltoid (the target muscle) was recorded during yawning. These peak EMG values were greatly facilitated in comparison with the session mean peak values obtained during an attempted maximum voluntary isometric contraction (shoulder flexion) of the same limb (e.g., Trial 1: 85.00 vs. 4.33 microV). The possibility of yawning as a confounding variable in EMG biofeedback studies is presented and discussed.

Aged↗

[Are ciliary abnormalities always present in Kartagener's syndrome? A study of 16 patients].

Kartagener's syndrome is defined as the combination of bronchiectasis, sinusitis and situs inversus. Assessment of characteristic ultrastructural changes and of their clinical expression was possible by examining the ciliated cells in the airways of 16 patients (12 children). Respiratory cilia of 11/13 patients were found to have abnormal motility. Quantitative ultrastructural data were obtained for 15 patients. Findings were absolutely normal in 2 cases. In 13 cases, ciliary abnormalities affected all the cilia, the majority of them (70-90%) or some of them (20-40%) (n = 7, n = 4, n = 2, respectively). The most frequently encountered aberration was a lacking external dynein arm. Summing it up: 1) ultrastructural ciliary abnormalities do not appear consistently in Kartagener's syndrome; 2) the lack of external dynein arms of cilia is the most frequent anomalous finding: 3) the clinical expression of ciliary dysfunction varies and the exact correlation between ultrastructural data and the intensity of the clinical manifestations remains to be established.

Adult↗

Toxicity of an attapulgite sample studied in vivo and in vitro.

Conflicting data are found in the literature concerning the carcinogenic potency of attapulgite. We tested the carcinogenic potency of French attapulgite in rats, and compared it with 2 chrysotile samples: Rhodesian UICC (Ch A) and short Canadian fibres (Ch C). The mean length of the fibres was 0.77 micron (attapulgite), 3.21 microns (Ch A) and 1.25 microns (Ch C). The mean diameter was 0.06 micron in the 3 samples. The particles (20 mg) in saline were inoculated into the pleural cavity of Sprague-Dawley rats allowed to survive for their full lifespan. The incidence rates of mesothelioma were: 0% (saline controls), 0% (attapulgite), 19% (ChC) and 48% (Ch A). In vitro studies were carried out using cultures of rat pleural mesothelial cells (RPMC). Attapulgite and Ch C did not modify cell growth except at high doses of 10 micrograms/cm2. Unscheduled DNA synthesis (UDS) was detected using [3H]thymidine incorporation in confluent RPMC (GoG1 arrested) and a scintillation method. UDS was stimulated with either Ch A or Ch C at doses ranging from 2 to 10 micrograms/cm2. In contrast, attapulgite did not significantly enhance [3H]thymidine incorporation at doses ranging from 2 to 20 micrograms/cm2. The results show that the attapulgite tested here had no carcinogenic potency. The in vivo and in vitro reactivity of the fibres used in this experiment might perhaps be related to the fibre size; however, other parameters may also be important.

Animals↗

[C3F8 in the treatment of retinal detachment associated with vitreoretinal proliferation].

The perfluoropropane gas was used as an adjunct to vitreoretinal microsurgery in 60 eyes of 60 patients with rhegmatogenous retinal detachment complicated by proliferative vitreoretinopathy. 0.3 ml to 1.8 ml (average 0.9 ml) of pure perfluoropropane gas was used. The surgical procedure included vitrectomy and scleral buckling in all patients. The follow-up after complete gas absorption ranged from 6 months to 3 years in the successful eyes. Total retinal reattachment was achieved in 41 eyes (68.3%). The anatomical success rate was 88% (22/25 eyes) in grade C1-C2 PVR cases, 68.7% (11/15 eyes) in grade C3-D1 PVR cases, and 42% (8/19 eyes) in grade D2-D3 PVR cases. Visual acuity of 0.1 or better was achieved in 80% of eyes with grade C PVR and 61% of eyes with grade D PVR. Visual acuity of 0.4 or better was achieved in 26.9% of eyes with grade C PVR. Macular changes were revealed by fluorescein angiography in 53% of successful eyes. We recommend the use of C3F8 rather than SF6 in the management of rhegmatogenous retinal detachment complicated by PVR. In our experience the anatomical success rate achieved with C3F8 is approximately the same as that achieved with SF6. However permanent retinal reattachment was achieved with a single operation in 87.8% of successful eyes of the present series of patients managed with C3F8 as compared to only 12% of successful eyes of a previous series of patients managed with SF6. The anatomical results achieved with a single operation in the C3F8 series are probably related to the greater longevity of C3F8 as compared to that of SF6.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Enhancement of adriamycin antitumor activity by its binding with an intracellular sustained-release form, polymethacrylate nanospheres, in U-937 cells.

We investigated the antitumor activity of Adriamycin on a monocytic-like cancer cell line U-937 after its binding on polymethacrylate nanospheres (diameter, 270-350 nm). Compared to free Adramycin (F-ADR), nanosphere-bound Adriamycin (B-ADR) exhibits a 3-fold enhancement of cytotoxicity, as determined by cell growth inhibition and DNA synthesis, after continuous exposure to 0.02 and 0.04 microgram/ml. The 90% growth inhibition concentration was 0.051 microgram/ml for F-ADR and was 0.018 microgram/ml for B-ADR (P less than 0.001). Furthermore, the nanosphere densities per cell play an important role since for the same drug concentration the higher the density increases, the better the activity is. Indeed, after 4 days of incubation in a medium containing 160 nanospheres at 0.5 fg/cell, the cell counts were 62.8 +/- 12.8% (SD) of the initial inoculum and they were only 16.1 +/- 0.1% after incubation in a medium containing 800 nanospheres at 0.1 fg/cell (P less than 0.001). A comparable enhancement of activity regarding the nanosphere densities was observed after a 24-h exposure to 0.02 and 0.05 microgram/ml. Short-term uptake studies showed that B-ADR accumulation was higher with B-ADR than with F-ADR. In addition, the efflux kinetics was modified. For cells exposed to F-ADR for 4 h, the efflux half-life was 23.7 +/- 7.7 h and the area to infinity under the efflux curve was 8.6 +/- 2.8 micrograms/mg protein x h-1. For cells exposed to B-ADR, the efflux half-life increased to 85.9 +/- 19.2 h and the area to infinity under the efflux curve to 29.6 +/- 6.6 micrograms/mg protein x h-1 (P less than 0.001). Electron transmission microscopy and previous findings have revealed that B-ADR was well internalized into cells. Our data support the hypothesis that B-ADR acts as an intracellular drug release complex after endocytosis. The findings regarding the number of nanospheres per cell and dose-effect relationships are consistent with mechanisms of drug actions extending to membrane domains.

Cell Compartmentation↗

Clinical evaluation of cervical facet joint infiltration.

Twenty-one patients with cervical facet syndrome underwent 39 facet joint infiltrations with corticosteroids using fluoroscopic guidance. There were 22 intra-articular and 17 peri-articular injections. This treatment relieved symptoms in 91% of patients. Follow-up ranged from one week to 12 months. However, symptoms usually recurred, specifically in 71% of patients with complete responses and in 42% of those with partial relief. There was no significant difference in response between patients receiving intra-articular or peri-articular injections (chi 2 = 2.283).

Adult↗

Evaluation of three assays on alveolar lavage fluid in the diagnosis of cytomegalovirus pneumonitis after bone marrow transplantation.

Cytologic examination, immunofluorescence assays, and cultures for virus were compared prospectively in the detection of cytomegalovirus (CMV) in cells obtained by 41 bronchoalveolar lavages (BALs) from 30 bone marrow transplant recipients with pneumonia. No evidence of CMV was found in 21 BALs. Viral inclusions, positive immunologic assays, and positive cultures were found in 14, 15, and 18 BALs, respectively. Cytological and immunologic results were closely related except in one BAL. In five BALs, a positive culture for virus was the sole criterion noted for diagnosis of CMV. The patients with both cytologically and immunologically positive results were more likely to die with or from respiratory failure (P less than .05), diffuse interstitial patterns (P less than .01), and severe acute graft-vs.-host disease (P less than .02) than were the patients without any criterion for diagnosis of CMV. The discrepancies with the previously reported data, the interpretation of the three diagnostic procedures, and the ability of BAL to diagnose CMV pneumonia are discussed.

Adolescent↗

Pleural carcinogenic potency of mineral fibers (asbestos, attapulgite) and their cytotoxicity on cultured cells.

The carcinogenicity of several samples of mineral fibers was tested following injection of 20 mg in the pleural cavity of noninbred Sprague-Dawley rats. Three samples of chrysotile asbestos (mean length: 3.2, 2.1, and 1.2 micron) induced mesotheliomas at a rate of 48, 52, and 19%, respectively. The first sample was acid leached prior to intrapleural injection; in that group, the percentage of mesotheliomas was reduced to 25%. Treatment with amosite and crocidolite resulted in the occurrence of 57 and 56% of mesotheliomas. Acid-treatment of amphiboles did not significantly modify the percentage of mesotheliomas. When the Stanton's fiber dimensions were taken into consideration to correlate with mesothelioma incidence, the observed number of mesotheliomas in the chrysotile-treated animals was much lower than that expected, suggesting that other fiber parameters (chemistry, physicochemistry) play a role in the carcinogenicity. Attapulgite fibers (mean length: 0.77 micron) did not induce tumor, and the mean survival time was of the same order as that observed in the control groups. The injection of quartz resulted in no mesothelioma but did result in 6 malignant histiocytic lymphomas (17%) and 2 malignant schwannomas (6%). In vitro experiments did not show strong correlation between cytotoxicity and the carcinogenic potency of these minerals, but the qualitative cellular responses might give some indications on the fiber's potency. In addition, the in vitro effects of the fibers seem to be modulated by their size.

Animals↗

[Comparative frequencies of the beats of nasal and bronchial ciliary cells. Study in 10 adults without respiratory pathology].

The frequencies of nasal and bronchial ciliated cell beats were compared in 10 adult subjects (mean age 56 years) with E.N.T. tumoral pathology but no recent respiratory disease. Ciliated cells were collected by simultaneous nasal curettage and bronchial brushing carried out under general anaesthesia during endoscopic evaluation of the tumors. The frequency of beats was measured by the stroboscopic method at room temperature (18 degrees-25 degrees C) at least 3 hours after cell collection. A significant (p less than 0.05) difference was found between nasal (8.89 +/- 0.84 Hz) and bronchial (9.6 +/- 1.03 Hz) beats. A study of nasal ciliated cell beats therefore provides a first assessment of ciliary function which is of interest in patients with recurrent respiratory diseases. It is a simple procedure that can easily be performed prior to more complex investigations, such as study of the bronchial ciliated cell beats or ultrastructural study of the cilia.

Aged↗

[Natural killer cells of the lung].

Natural killer cells are lymphocytes which spontaneously destroy tumoral or virus-infected cells in vitro. They are identified on morphological criteria (LGL) and/or on the presence of "surface markers". However, none of these criteria is specific, and they can only be defined by their spontaneous cytolytic activity. These cells, present in numerous organs, have been particularly studied in blood and lymphoid tissue. They intervene in defence mechanisms against virus-infected cells, in the graft-versus-host reaction and in immunosurveillance or tumours. Few studies have been devoted to natural killer cells of the lung. They are present in that organ in the same proportion of lymphocyte population as in blood, but their activity is inhibited by the local microenvironment.

Antigens, Surface↗

Large granular lymphocytes in bronchoalveolar lavage fluids from immunocompromised patients with cytomegalovirus pneumonitis.

Natural killer (NK) cells activities had been demonstrated to be depressed in patients with fatal cytomegalovirus (CMV) pneumonitis. NK cells can be identified by morphologic features characteristic of large granular lymphocytes (LGLs). Bronchoalveolar lavage (BAL) cells from 16 immunocompromised patients with CMV pneumonitis were analyzed. Two different groups of patients could be distinguished depending on the course of the CMV pneumonitis: nine patients who recovered (Group A), seven patients with a fatal outcome (Group B). Except for the increase in polymorphonuclear cells (PMN) in Group B (12.4 +/- 11.6%), no significant difference in the macrophage or the total lymphocyte population was observed. A differential count excluding alveolar macrophages specified the percentage of LGLs from the total lymphocyte population. The LGLs in Group A (7.1 +/- 9.9%) were similar to those previously reported in normal lung. A significant increase in LGLs was observed in the BAL cells from patients of Group B (28.1 +/- 22%). The discrepancy between the high percentage of LGLs in patients with a fatal outcome and their expected protective effects is discussed.

Bronchi↗

Parkinsonian syndrome and central nervous system lymphoma involving the substantia nigra. A case report.

The clinical history and postmortem neuropathologic findings of a case of cerebral lymphoma revealed by a typical parkinsonian syndrome are reported. The clinical symptoms initially improved with dopa therapy. The tumor was classified as a diffuse, non-cleaved, large-cell lymphoma of B-cell origin producing monoclonal lambda light chains. The substantia nigra was infiltrated by the tumor and showed neuronal loss and extraneuronal pigment. The most striking histological feature was the presence of neuronophagic-like nodules composed of lymphomatous cells both in the locus niger and in the left thalamus. No tumoral mass effect and no histological stigmata of other etiologies of parkinsonian syndromes were observed. A hypothesis is that the neuronophagic-like nodules may reflect a neuronotoxic activity of the lymphoma and may be considered at the origin of parkinsonism.

B-Lymphocytes↗

Diagnostic yield of bronchoalveolar lavage in pneumonitis occurring after allogeneic bone marrow transplantation.

Fifty-two bronchoalveolar lavages (BAL) were performed in order to investigate 46 episodes of pneumonitis that occurred after allogeneic bone-marrow transplantation. No complications have been attributed to this procedure. A specific etiologic diagnosis was obtained in 24 of 46 episodes (52%) by 26 of 52 BAL (50%). Cytomegalovirus (CMV), diagnosed by the presence of typical inclusions, was the pathogen most frequently identified by BAL (13 of 46 episodes) and was associated with other causes of pneumonia in 4 patients. The other causes of pneumonitis diagnosed by BAL were: giant-cell pneumonia: 1, aspergillosis alone: 3, Pneumocystis carinii: 1, Hemophilus influenzae: 3, isolated pulmonary hemorrhage: 3. One false negative (aspergillosis, n = 1) was diagnosed at autopsy. The overall mortality rate of these episodes was 24%. Thus, BAL appears to be a rapid and reproducible diagnostic method for monitoring pneumonitis in grafted patients, particularly CMV pneumonitis, and may avoid the need for surgical biopsy.

Adolescent↗

Electron-microscopic immunohistochemical study of the localization of immunoglobulin G in the choroid plexus of the rat.

The localization of autologous antiperoxidase immunoglobulin G (IgG) was studied in the choroid plexus of Lewis rats immunized against horseradish peroxidase (HRP). This experiment was performed to study the permeability of the choroid plexus to intravascular IgG. It was shown that autologous IgG was present in the extravascular spaces. The transendothelial transfer appeared to occur mainly via the fenestrations and some interendothelial junctions. No transfer of IgG at the level of epithelial cells toward the cerebrospinal fluid was demonstrated. Interstitial spaces in contact with the connective-tissue cells of the choroid stroma were strongly labeled. The significance of these spaces remains hypothetical and raises the question of the fate of IgG from the interstitial space.

Animals↗