Search PubMed⌕ Search

Biomedical subjects

D Bergeron

Publications and source records attributed to D Bergeron.

At least 55 records · Page 3Linked to original sources
PubMed1992

Determinants of thymotropism in Kaplan radiation leukemia virus and nucleotide sequence of its envelope region.

Radiation leukemia viruses (RadLVs) are a group of murine leukemia viruses which are induced by radiation and cause T-cell leukemia. Viral clones isolated from the BL/VL3 lymphoid cell line derived from a thymoma show variable tropism and leukemogenic potential. We have constructed chimeric viruses by in vitro recombination between two viruses, a RadLV that is thymotropic and an endogenous ecotropic virus that is nonthymotropic. We show here that, in contrast to thymotropism determinants identified previously, which lie in the long terminal repeat (LTR), it is the envelope region that is responsible for the thymotropism of BL/VL3 RadLV. The nonthymotropic virus which we have rendered thymotropic by transfer of the env region of RadLV in the present study has been shown previously to become thymotropic when the LTR of another thymotropic virus is inserted in its genome. Thus, the LTR and envelope gene may be involved in complementary action to lead to thymotropism.

Amino Acid Sequence↗
PubMed1991

High-yield method for directional cDNA library construction.

Improvement of a cDNA synthesis procedure using a single stranded (ss) vector primer [Bellemare et al., Gene 52 (1987) 11-19] is reported. This vector (pPBS27), upon linearization with XbaI using an appropriate restriction site-directed fragment, releases a thymidilic tail used to prime cDNA synthesis. DNA polymerase I and RNase H replace the RNA strand and replicate the vector before double-stranded (ds) blunt-end ligation with T4 DNA ligase. More than 10(7) cfu/microgram of vector can be obtained with an efficient transformation protocol using either globin-encoding or 7.5-kb poly(A)-tailed RNA. This improved cloning method is easier, faster and a few hundred times more efficient than the original procedure as it involves ds rather than ss DNA for transformation.

Base Sequence↗
PubMed1991

The human homolog of the mouse common viral integration region, FLI1, maps to 11q23-q24.

FLI1 is a common mouse viral integration region in virus-induced leukemias and lymphomas. Using an evolutionarily conserved mouse probe and Southern hybridization to (rodent x human) somatic cell hybrid DNAs, the human homolog of FLI1 has been shown to lie on a fragment of chromosome 11 flanked on the centromeric side by the acute lymphoblastic leukemia-associated t(4;11)(q21;q23) translocation breakpoint and on the telomeric side by the Ewing- and neuroepithelioma-associated t(11;22) (q24;q12) breakpoint.

Animals↗
PubMed1991

Identification of a common viral integration region in Cas-Br-E murine leukemia virus-induced non-T-, non-B-cell lymphomas.

The Cas-Br-E murine leukemia virus is a nondefective retrovirus that induces non-T-, non-B-cell lymphomas in susceptible NIH/Swiss mice. By using a DNA probe derived from Cas-Br-E provirus-flanking sequences, we identified a DNA region, originally called Sic-1, rearranged in 16 of 24 tumors analyzed (67%). All proviruses were integrated in a DNA segment smaller than 100 bp and were in the same 5'-to-3' orientation. Ecotropic as well as mink cell focus-forming virus types were found integrated in that specific DNA region. On the basis of Southern blot analysis of somatic cell hybrids and progeny of an interspecies backcross, the Sic-1 region was localized on mouse chromosome 9 near the previously described proto-oncogenes or common viral integration sites: Ets-1, Cbl-2, Tpl-1, and Fli-1. Restriction map analysis shows that this region is identical to the Fli-1 locus identified in Friend murine leukemia virus-induced erythroleukemia cell lines and thus may contain sequences also responsible for the development of mouse non-T-, non-B-cell lymphomas.

Animals↗
PubMed1990

[A new space for feminine desire].

Psychoanalitical literature evolved around the idea of a space for desire structured according to the boy-mother relationship model. Is the feminine clinical approach, together with the historical contribution of feminism, discovering a new space for feminine desire? The psychotic female, for whom the role of the father has no meaning in the mother's discourse, refuses the Law as a symbol of social authority. As for the hysteric female, she does not rely on the Father as a safeguard against the emptyness that lies behind the Laws and the beliefs of men. In its own way, feminism adopts these positions of psychotic rejection and hysteric contestation by projecting them on to the social landscape. Furthermore, feminism requires new forms of social interaction that embody the esthetical space women need to experience life as full-fledged citizens.

Cultural Characteristics↗
PubMed1989

Cystic schwannoma of the brainstem.

A rare case of cystic schwannoma occurring in the brainstem in the absence of von Recklinghausen's disease is reported. This appears to be the first case in the literature of a cystic schwannoma ever described in this location. While the exact origin of this tumor in this unusual location remains uncertain, different hypotheses are discussed and the possible origin of this tumor from perivascular elements in the brainstem is seriously considered.

Brain Neoplasms↗
PubMed1989

[Post-intubation right paratracheal abscess. Apropos of a case].

We report the case of a young woman who had undergone a difficult emergency intubation and rapidly developed a mediastinal collection of pus. Mediastinoscopy, requested for diagnostic purposes, was also therapeutic as it drained the abscess. The patient received a course of antibiotics and was cured without sequelae. Accidents of tracheal intubation are severe, especially when unrecognized. They often include perforation of the oesophagus resulting in mediastinitis or abscess with an estimated 30 to 40% mortality rate, and they constitute a medico-surgical emergency. In the case reported here mediastinoscopy was crucial, but the theoretical value of computerized tomography must be stressed since this method not only detects the lesion but is also used to perform a guided drainage.

Abscess↗
PubMed1988

Imaging the pneumoconioses: a multidisciplinary approach.

The initial early reaction of pulmonary tissue to inorganic dust inhalation is a fibrosing macrophagic alveolitis. This initial pulmonary lesion can be detected by an enhanced gallium 67 pulmonary uptake and analyses of bronchoalveolar lavage. These two techniques can document not only the increased proliferation of macrophages, but also the activation of macrophages to produce excessive amounts of fibronectin and other factors of fibroblastic growth implicated in the pathogenesis of the pneumoconioses. Of equal clinical interest is the development of computed tomography, which has permitted better characterization of the early stages of fibrosis in the pneumoconioses. These refinements in disease recognition will contribute to the earlier detection of pneumoconioses before they become incapacitating. Newer therapeutic methods are also under investigation that could permit inactivation of either the dust itself or the pulmonary macrophage. The coupling of these new diagnostic and therapeutic developments will bring in a new era in occupational pulmonary medicine.

Bronchoalveolar Lavage Fluid↗
PubMed1988

Lung function in silica-exposed workers. A relationship to disease severity assessed by CT scan.

To investigate the relationship of lung function, airflow limitation, and lung injury in silica-exposed workers, we analyzed the clinical, functional, and radiologic data of 94 long-term workers exposed in the granite industry or in foundries. The subjects were divided into four subsets based on chest roentgenogram and CT scan of the thorax: group 1 consisted of 21 subjects with category 0 chest roentgenogram and category 0 CT scan; group 2, 28 subjects with category E 1 on both chest roentgenogram and CT scan; group 3, 18 subjects with category E 1 on chest roentgenogram but with coalescence or conglomeration or both seen only on CT scan; and group 4, 27 subjects with category E 1 and coalescence or conglomeration or both on roentgenogram and CT scan. The groups did not differ in terms of age, height, cigarette smoking, or years of exposure. Lung volumes were significantly reduced only in group 4 (p less than 0.05). Lung compliance, diffusion capacity, and the rest-exercise P(A-a)O2 gradient were reduced in groups 3 and 4 (p less than 0.05). Expiratory flow rates were significantly reduced in groups 2, 3, and 4, with the lowest values in group 4. The expiratory flow rates in group 3 were significantly lower in group 3 than in group 2. These results support the concept that airflow in silica-exposed workers is significantly reduced when the disease is detectable on simple chest roentgenogram; coalescence or conglomeration or both on chest roentgenogram or CT scan is associated with significant loss of lung volumes, gas exchange function, and increased airflow obstruction.

Humans↗
PubMed1988

[New methods in the early detection of pulmonary fibrosis in asbestosis and silicosis].

Much recent work in thoracic medicine has been slanted towards the early detection of respiratory disease and the prevention of disabling sequelae. In the field of pneumoconioses associated with inhalation of mineral dust the interest of research workers has been largely orientated towards the objectives of early detection and the prevention of fibrotic scarring. To achieve real progress the research workers have used new investigational techniques such as axial tomography of the thorax, quantitative scintigraphy using Gallium-67 and analyses of bronchiolar lavage in parallel with a traditional approach, namely: a clinical examination of the patient, a pulmonary radiograph and respiratory function tests. These studies have enabled further clarification of the specific value of each of these new methods of investigation, whether at the level of early detection, the early recognition of pulmonary fibrosis, the characterisation of the current state of the disease and the prediction of fibrogenic power. Several different forms of intervention on the fibrotic process are currently under trial and may contribute to the prevention of pulmonary fibrosis.

Asbestosis↗
PubMed1988

[Post-traumatic pneumatocele and hemato-pneumatocele of the lung. Apropos of 3 cases].

Pneumatocele and haemato-pneumatocele are air or air/fluid cavitary lesions which develop in the lung parenchyma after thoracic trauma. The formation of this lesion requires a direct violent impact on the pliable lung wall which explains its frequency in young adults. They are preferentially localised in the lung bases. The importance of associated lesions often marks the pneumatocele. Though rarely described, its frequency is certainly underestimated. If haemoptysis is the most frequent clinical sign it is the chest x-ray which demonstrates the early abnormality in the form of a rounded translucent image with a fine contour and variable diameter. The existence of a fluid level suggests the presence of blood (haemato-pneumatocele). The differential diagnosis with a localised pneumothorax, a diaphragmatic hernia and a pre-existing cystic lesion is easy as a rule but an evacuated pulmonary haematoma may lead to the discussion, especially as the mechanism of their formation may be the same. In isolation their clinical implications are minimal, their evolution favourable and after several weeks with a restitution of the integrity of the pulmonary parenchyma the absence of therapeutic intervention is justified.

Adolescent↗
PubMed1987

CT assessment of silicosis in exposed workers.

For evaluation of the clinical usefulness of CT of the thorax in workers exposed to silica, 58 workers with long-term exposure to silica in the granite and foundry industries of the Eastern Townships of Quebec were examined. CT scans were compared with standard posteroanterior chest radiographs by using the International Labour Office 1980 grading system for silicosis. Six areas of the lung in each patient were assessed by both techniques for profusion (number) of opacities (small nodules), coalescence, and the presence of large opacities. CT scans and chest radiographs yielded similar average scores for detection of opacities. CT identified significantly more coalescence and large opacities in patients with simple silicosis. In patients with complicated silicosis, CT results were comparable with those of chest radiographs. CT of the thorax in workers exposed to silica does not identify more patients with minimal parenchymal disease, but it does detect earlier changes of coalescence.

Humans↗
PubMed1987

Aseptic necrosis of the cricoid: a complication of tracheal intubation.

Necrosis of the cricoid is a rare complication of tracheal intubation. Almost all cases previously reported were purulent. A 25-year-old man presented with a respiratory distress, two months after 2 days of tracheal intubation. The posterior larynx was the site of a major inflammation with fixity of the arytenoids. After an emergency control of the airway in the acute phase, a posterior cricoid split with widening by a laryngeal stent was performed for treatment of sequelae. Evolutional data from clinical examinations, direct fiberoptic laryngoscopy, CT scan, respiratory function tests, and pathology are described. Successive phases of latency, then acute manifestations, then sequelae can be distinguished. The work-up did not reveal any sign in favor of a septic necrosis. A physiopathologic hypothesis is suggested, explaining the necrosis as an ischemic one, due to destruction of the internal perichondrium vascular network of the cricoid.

Acute Disease↗
PubMed1986

[For a new clinical approach to psychosis : the " 388 "].

The history of the last thirty years of North-American psychiatry points up the difficulties encountered in the treatment of psychotic patients in a hospital setting but also in the maintaining of their social integration. In a search for solutions, and taking into account the needs observed at the Robert-Giffard Hospital in Quebec, a group of professionals of GIFRIC decided to open, in the center of town, a Psychoanalytical Center for psychotics. Operating since 1982, the "388" is arming at a social réintégration of the psychotic patients in order to read a more satisfying life according to their possibilities of co-existence with others. It is an outside of the hospital structure which permits the treatment of the crisis as well as providing longterm care. The care and services given are based on a psychoanalytical frame. This paper describes the clientele, the services offered, the treatment, the patients' evolution and the problems that arise from the evaluation of such a new structure.

English Abstract↗
PubMed1986

[Diagnosis of inflammatory sacroiliitis. Comparison of complementary examinations].

In order to test the sensitivity of different techniques in the diagnosis of sacroiliitis, we have made a prospective and non-controlled study of 22 patients using standard radiography of the sacroiliac joint; conventional tomography and axial scintigraphy (calculation of an ISI sacroiliac index). The normal upper limit of the sacroiliac index (1.42) was studied in parallel, using a group of 63 control subjects. Correlation between the radiological examinations was average, but was very poor between radiology and scintigraphy. Conventional tomography and calculation of the sacroiliac index were of equal value diagnostically. Clear images of juxta-articular geodes were seen during scanning, but were not taken into account in the diagnosis. They may represent the onset of larger erosions and need to be verified.

Adolescent↗
PubMed1984

Radiographic assessment of pleuropulmonary disease in asbestos workers: posteroanterior, four view films, and computed tomograms of the thorax.

To study the clinical usefulness of computed tomography (CT) scanning of the thorax in asbestos related pleuropulmonary disease, 127 long term asbestos workers of the mines and mills in the Eastern Townships of Québec were examined. The CT scan was compared with the standard posteroanterior (PA) chest film and the four view films using the ILO grading system for profusion of disease. Six lung areas and six pleural sites were studied. On the basis of the usual diagnostic criteria, 41% of the workers had asbestosis. For profusion of parenchymal disease, there was an excellent correlation (r = 0.96, p less than 0.001) between PA and four view films and the latter did not significantly increase the total profusion score; the CT scan correlated less well with the PA film (r = 0.79, p less than 0.01) and the scatter of the data was larger. In 10 of the 53 (19%) workers with asbestosis the pulmonary lesions were not recognised by CT scan. For profusion of pleural plaques, there was an excellent correlation (p = 0.91, p less than 0.001) between PA and four view films; scores were identical in 73%, higher for PA in 7%, and higher for four view films in 19%. CT scan scores, however, were identical with PA films in 31%, higher for CT scan in 13% (owing to higher scores on lateral pleural sites), and lower for CT scan in 56% (owing to lower scores at diaphragm and costophrenic angle sites). Pleural calcifications were identified in 24 workers for a total of 40 sites; 13 as possible, 31% identified by two modes, and 27 as definite. Of the latter, 14 were seen only on CT scan. In the workers with rigid pressure volume curve of the lung and increased Gallium-67 lung uptake only, CT scan total scores were not significantly higher than in those without these markers of early interstitial lung disease (5 +/- 1 v 4 +/- 1, p less than 0.05). Thus the four view films and CT scan appear to be useful mainly in the assessment of pleural disease. The four view film identifies more sites of pleural plaques and the CT scan more pleural calcified plaques.

Adult↗