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Biomedical subjects

F Gouin

Publications and source records attributed to F Gouin.

At least 55 records · Page 3Linked to original sources

Presence of leukaemia inhibitory factor (LIF) and LIF-receptor chain (gp190) in osteoclast-like cells cultured from human giant cell tumour of bone. Ultrastructural distribution.

The behaviour of multinucleated giant cells (MNC) obtained from a giant cell tumour of the tibia and cultured on glass coverslips or on devitalized dentin slices was investigated using light and electron microscopy. Cells were studied in the presence or absence of LIF a cytokine known to be involved in bone turnover and to act as a growth factor in some solid tumours. The direct effect of LIF on MNC was examined by a post-embedding colloidal gold immunocytochemistry process using human anti-LIF and anti-LIF-receptor (chain gp190) antibodies. After 7 days of culture, the MNC obtained displayed osteoclast immunocytochemical features. Moreover, these MNC were able to resorb large amounts of dentin and presented typical features of active osteoclasts. Immunolocalization of LIF and LIF-receptor revealed the presence of this cytokine and its receptor within the cytoplasm and nucleus of active resorbing MNC. LIF upmodulated MNC number and nucleation but decreased their ability to resorb dentin. The present study suggests that MNC obtained from human GCT, currently considered as osteoclast-like cells, are targets for LIF and may be a source of LIF production in this pathological condition.

Bone Neoplasms↗

Upper-extremity deep vein thrombosis after central venous catheterization via the axillary vein.

OBJECTIVE: To determine the frequency of central venous catheter-induced thrombosis of the axillary vein. DESIGN: Prospective, controlled study. SETTING: Tertiary care university center. PATIENTS: Sixty patients in a medical-surgical intensive care unit who required central venous catheterization via the axillary vein. INTERVENTIONS: Single-lumen, silicone elastomer or polyurethane catheters were inserted for a mean duration of 14.7+/-7.4 days (range, 4-33 days). On catheter removal, bilateral upper-extremity phlebographic examination was performed in each patient. The incidence of deep vein thrombosis in catheterized arms was compared with that in uncatheterized arms. MEASUREMENTS AND MAIN RESULTS: Of the 60 patients who underwent axillary vein cannulation, one patient had clinical signs of arm vein thrombosis, but no patient had clinical sign of pulmonary embolism. There were 35 patients (58.3%) who developed positive phlebographic examinations homolateral to the catheter. Fibrin sleeves that developed around the catheters were observed in 28 patients (47%). Five patients (8.3%) had phlebographic signs of partial axillary vein thrombosis: nonobstructive clots adherent to the vessel wall and/or the catheter. Two patients (3.3%) had phlebographic signs of complete axillary vein thrombosis. No thrombosis was observed in patients with catheterizations lasting < or =6 days, two cases were observed for duration of 7-14 days, and five cases were observed for duration of > or =15 days (p < .01). In the seven patients with axillary vein thrombosis, the vessel was cannulated with fewer than three puncture attempts, and the mean duration for catheter insertion (10+/-2.5 min) was not different from that of patients with no axillary vein thrombosis (14+/-9 min). CONCLUSIONS: Based on the data from the present study, we conclude that axillary vein catheterization is associated with a 11.6% frequency of upper-extremity deep vein thrombosis. This rate of vein thrombosis is similar to that observed after internal jugular or subclavian vein cannulation. Given the acceptable rate of this clinically important complication, axillary vein cannulation offers an attractive alternative site for catheter insertion to the internal jugular or subclavian vein in the critically ill. Because thrombosis is rare or absent in catheterizations lasting <15 days, it seems wise to withdraw axillary catheters after a maximum of 2 wks.

Arm↗

[Physiopathology of tumor-induced osteolysis].

Osteolysis, the most common expression of bone tumor, can cause pain, pathological fracture, epidural spinal cord compression and hypercalcemia. Multinucleated osteoclast-like cells, the main agents in bone resorption, are numerous in benign giant cell tumor of bone and can be recruited and activated by various carcinoma cell lines in vitro in animal models. Polykarion macrophages are also able to resorb bone matrix in a favourable tumoral environment. Direct bone resorption by tumor cells has recently been described in vitro and in vivo in animals. The presence of diffusible substances such as hormones, cytokines and growth factors creates a favourable microenvironment for stimulation of osteoclast-like cells and polykarion macrophages functional ability to resorb bone matrix. These mediators act within a complex but still unelucidated network involving high cell production (tumor cells, normal and reactional stroma as well as hematopoietic cells) and many targets (tumor production (tumor cells, normal and reactional stroma as well as hematopoietic cells) and many targets (tumor cells, monocyte/macrophage lineage cells, and osteoclast-like cells). The presence in the same environment of all these stimulating factors for tumor cell growth and resorbing ability could explain the vicious circle of tumoral and osteolytic progression. A better understanding of the complex mechanism of tumor induced osteolysis is essential for improving the conventional surgical approach to this pathology.

Animals↗

Multiple rheumatoid bursitis with migrating chylous cysts. Report of a case in a European woman and review of the literature.

We report a case of recurrent multiple bursitis (19 episodes at nine sites) requiring seven surgical procedures in a European women with a 38-year history of severe, nodular, destructive seropositive rheumatoid arthritis unresponsive to second-line drugs. The episodes of bursitis were not correlated with activity of the joint disease. Some cysts migrated over a considerable distance. At least two cysts contained chylous fluid. The histologic study of one cyst demonstrated a cholesterol crystal granuloma. Potential relationships linking cholesterol crystals, chylous cysts, and migrating multiple bursitis are discussed. The relevant literature is reviewed.

Aged↗

Oncostatin M stimulates macrophage-polykaryon formation in long-term human bone-marrow cultures.

Though oncostatin M (OSM) is a potent mediator of the inflammatory reaction, its role in inflammation and bone resorption is still unclear. A long-term bone-marrow culture system is usually developed to allow the formation of multinucleated cells (MNC) and was used here to define the effects of human recombinant OSM on human MNC formation. OSM significantly upregulated (1.9- to 5.6-fold) the number of MNC in these cultures in a dose- and time-dependent manner. Cell nucleation and tartrate-resistant acid phosphatase activity were also increased. MNC did not display osteoclast characteristics, such as response to calcitonin and failure to resorb dentin surface. However, they expressed a non-specific alpha-naphthyl acetate esterase as well as macrophage differentiation antigens (CD11b, CD13 and CD33) and were able to perform phagocytosis. Similar effects were observed after addition of 1 alpha, 25-dihydroxyvitamin D3. Moreover, in these culture conditions, human bone-marrow mononuclear cells were capable of low-grade resorption in the presence of bone-marrow stromal cells. This low-grade resorption was significantly inhibited by addition of 25 ng/ml OSM. Our data demonstrate for the first time that human recombinant OSM significantly stimulates the formation of MNC and could be involved in the inflammatory process via macrophage-polykaryon formation from human bone marrow.

Acid Phosphatase↗

Increased levels of leukaemia inhibitory factor (LIF) in urine and tissue culture supernatant from human primary bone tumours.

Fifty-five adult patients with primary bone tumour, 27 benign and 28 malignant tumours, were assayed for leukaemia inhibitory factor (LIF) in urine and serum samples. Supernatant was obtained from primary tumour tissue cultures in 24 cases (14 benign, 10 malignant tumours). LIF was found in 11 urine samples (16.7%, 1 benign and 10 malignant tumours). In 23 urine samples from patients with malignant bone tumour tested before any treatment, LIF was detectable in eight cases (34.7%). High LIF levels were found in all supernatants from malignant tumour cultures and in supernatant from 12 of the 14 benign tumours cultured. LIF was never detected in control urine samples or supernatants from normal cancelous bone cultures. These first in vivo data concerning LIF in primary bone tumours raise the question as to the cellular origin of this multifunctional cytokine and its potential role in solid bone tumours and bone tumour resorption.

Adolescent↗

Cytokines, growth factors and osteoclasts.

Osteoclasts, the main protagonists involved in bone resorption mechanisms, are generally considered to be of haematopoietic origin, although the exact nature of the primary osteoclastic stem cells is still unknown. In vitro cellular models developed to study the different events of osteoclastic differentiation have revealed that not only several cell types (osteoblasts, monocytes, lymphocytes, etc.) but also many soluble factors (cytokines, hormones, vitamins, ions, etc.) and extracellular matrix elements (osteopontin, osteocalcin, etc.) are involved in osteoclastic differentiation and activation. This article provides an exhaustive review of recent knowledge on the origin of the osteoclast and the main substances involved in the osteoclastogenesis and activation of these cells.

Animals↗

Growth hormone stimulates multinucleated cell formation in long-term bone marrow cultures.

Although the effects of growth hormone on bone metabolism are well-documented, their role in the regulation of immune responses such as the inflammatory process has not been thoroughly explored. This study investigated the formation of multinucleated cells (MNC) in long-term human bone marrow cultures. Experiments using 1 and 100 ng/ml of human recombinant growth hormone (hGH) and 10(-7) M of 1,25 dihydroxyvitamin D3 (VD3) showed that hGH increased the total number and nucleation of MNC. The effects of hGH were generally greater than those observed with VD3. Cytological and immunological characterization of MNC revealed several macrophage polykaryon features. MNC did not respond to calcitonin in a cyclic adenosine monophosphate assay and failed to resorb dentin slices. These results demonstrate that MNC formed in the presence of hGH and VD3 present an essentially macrophage polykaryon phenotype. In this context, growth hormone may be involved in the inflammatory process through upmodulation of macrophage polykaryon formation.

Acid Phosphatase↗

Growth hormone stimulatory effects on osteoclastic resorption are partly mediated by insulin-like growth factor I: an in vitro study.

This study investigated the possible role in vitro of insulin-like growth factor I (IGF-I) as a mediator of the effects of growth hormone (GH) on osteoclastic resorption in an unfractioned rabbit bone cell model. After 4 days of rabbit bone cell culture, human GH (hGH) (50 ng/mL) and human IGF-I (hIGF-I) (50 ng/mL) significantly increased the formation of osteoclast-like cells with a lower level than parathyroid hormone (50 ng/mL) or VD3 (10(-8) mol/L). As well as parathyroid hormone and 1-alpha,25-dihydroxyvitamin D3, addition of hGH (1, 10, and 50 ng/mL) and hIGF-I (1, 10, and 50 ng/mL) stimulated the resorption activity of osteoclasts in terms of the percentage of dentin slice surface resorbed, number of lacunae per surface unit, and mean area of lacunae as compared to the control. When neutralizing antiserum against hIGF-I (4 micrograms/mL) was added at the start of culture, the stimulatory effects of hIGF-I and hGH on osteoclastic resorption activity were totally abolished. These results indicate that the effects of GH stimulation on osteoclastic resorption in vitro are mediated via local IGF-I secretion by stromal cells such as osteoblasts. As IGF-I receptors have recently been reported on rabbit osteoclasts, a direct action of IGF-I on mature osteoclasts could be envisaged. Further experiments will be required to determine the real level of IGF-I implicated in the stimulation of bone osteoclastic resorption.

Acid Phosphatase↗

Open-lung biopsy in patients with acute respiratory distress syndrome.

BACKGROUND: It has been suggested that fibrosis present during the fibroproliferative phase of acute respiratory distress syndrome (ARDS) can be treated by corticosteroids. However, neither clinical nor microbiologic criteria permit differentiation of this fibroproliferative phase from a nosocomial pneumonia. The aim of this observational case series was to evaluate the safety and utility of open-lung biopsy (OLB) performed in patients receiving ventilatory support who had persistent ARDS despite negative bacterial cultures. METHODS: During a 4-yr period, 37 OLBs were performed in 36 of 197 patients receiving ventilatory support who had ARDS. The severity of ARDS was assessed by a lung injury score of 3.1 +/- 0.4 (mean +/- SD) and a median ratio of the partial pressure of oxygen (PaO2) to the fraction of inspired oxygen (FiO2) of 118 mmHg. Histologic examination; bacterial, fungal, and acid-fast staining; and cultures of the tissue sample were performed. RESULTS: Fibrosis was present in only 41% of the lung specimens obtained by OLB. Only six patients received corticosteroids (17%). In 9 of the 15 patients with fibrosis, cytomegalovirus pneumonia precluded the use of corticosteroids. Histologic cytomegalovirus pneumonia was diagnosed in 18 cases. Histologic bacterial or mycobacterial pneumonia was diagnosed in five cases. No significant change in arterial blood gases was noted as linked to the biopsy procedure except an increase of the PaO2/FiO2 ratio. One pneumothorax was diagnosed on a chest roentgenogram 12 h after OLB. Only one patient required blood transfusion during the 48-h period after OLB (for an hemothorax). Five patients had moderate air leaks from operative chest tubes for 2-10 days. CONCLUSIONS: Open lung biopsy appeared to be a useful and acceptably safe diagnostic technique in patients with ARDS. It permitted the diagnosis of unexpected cytomegalovirus pneumonia.

APACHE↗

Does norepinephrine modify the effects of inhaled nitric oxide in septic patients with acute respiratory distress syndrome?

UNLABELLED: Hypoxia-related pulmonary vasoconstriction enhanced by norepinephrine could be deleterious in patients with the acute respiratory distress syndrome (ARDS) and sepsis. A prospective study compared the effects of nitric oxide on cardiorespiratory parameters, including the evaluation of right ventricular function in patients with ARDS and sepsis who were receiving or not receiving norepinephrine. METHODS: During a 15-month period, 27 patients with ARDS and sepsis were prospectively investigated (group 1: 15 patients not receiving norepinephrine; group 2: 12 patients receiving norepinephrine). Right ventricular ejection fraction was measured by thermodilution. After baseline measurements, nitric oxide was administered at increasing inspiratory concentrations. RESULTS: The ratio of oxygen tension in arterial blood to the fractional concentration of oxygen in inspired gas increased in the two groups. After logarithmic transformation of the data, an analysis of variance was performed that did not show any difference between the two groups. A dose-dependent decrease in mean pulmonary arterial pressure was observed in the two groups. This decrease and the increase in right ventricular ejection fraction induced by inhaled nitric oxide were more marked when patients received norepinephrine (P < 0.0001). CONCLUSION: Norepinephrine did not influence the beneficial effects of inhaled nitric oxide administered to patients with ARDS and sepsis on oxygenation.

Acute Disease↗

Catheter-related infections following axillary vein catheterization.

BACKGROUND: The aim of this study was to determine the rate of infectious complications following axillary vein cannulation and to compare to that observed after internal jugular vein catheterization. METHODS: A prospective comparative open study was carried out to determine the rate of infectious complications related to the use of catheters inserted via the axillary vein or the internal jugular vein. During the study period all patients submitted to central venous catheterization were evaluated. A total of 141 patients entered and completed the study. Catheter insertion sites were either the axillary vein punctured in the axilla, or the internal jugular vein punctured using an anterior approach. Catheter tips were cultured using a quantitative technique. Clinical information pertaining to the analysis was prospectively collected. RESULTS: A total of 141 catheters from 141 patients entered was studied. Clinical characteristics and risk factors for catheter infection were similar in both groups. The incidence of catheter-related infection (including catheter-related sepsis, and bacteremia) was not different between the two groups (axillary vein: 8.1%; internal jugular vein: 7.6%). Catheter-related bacteremia were seen at a rate of 3.7% in the internal jugular vein group and a rate of 1.6% in the axillary vein group (NS). The incidence of catheter colonization was similar in both groups (axillary vein: 14.5%; internal jugular vein: 11.4%). CONCLUSION: Catheter-related infection after axillary vein catheterization was similar to that observed after internal jugular vein catheterization. The chance of developing catheter-related sepsis was less than 10% with either route when catheters were used for the treatment of severely ill patients.

Analysis of Variance↗

Respective and combined effects of prone position and inhaled nitric oxide in patients with acute respiratory distress syndrome.

Inhaled nitric oxide (NO) and prone position (PP) are two of the new therapeutics proposed in the setting of acute respiratory distress syndrome (ARDS). The aim of this study was to evaluate the hemodynamic and respiratory effects of NO and prone position in patients with ARDS. Fourteen patients, sedated, paralyzed, and ventilated using volume-control mode, were prospectively investigated. All patients had a radial artery catheter, a pulmonary artery catheter, and a 3-F fiberoptic thermistor catheter advanced via the femoral artery into the descending aorta. The protocol consisted of seven phases: baseline measurements in supine position, SP (T0); SP + NO (T1); baseline 2 in SP (T2); PP without NO (T3); NO + PP (T4); SP + NO (T5); and PP + NO (T6). Inhaled NO (T1) induced an increase in PO2/FI(O2) (from 128 +/- 44 to 180 +/- 75 mm Hg, p < 0.004). Prone position (T3) resulted in an increase in PO2/FI(O2) (193 +/- 83 mm Hg, p < 0.003 versus T0). The association of NO with PP (T4) resulted in a significant improvement in PO2/FI(O2) (261 +/- 98 mm Hg) when compared with T0, T1, and T3. Analysis of variance showed a significant and additive effect of NO and PP on both PO2/FI(O2) (p < 0.000) and shunt fraction (QS/QT) (p < 0.01). Since the association of NO with PP presents additive effects on oxygenation, this association can be proposed for the treatment of ARDS.

Administration, Inhalation↗

[Combined tibio-talar and subtalar arthrodesis by retrograde nail in hindfoot rheumatoid arthritis].

PURPOSE OF THE STUDY: Many techniques for ankle arthrodesis have been described. Some are not applicable to patients with severe rheumatoid arthritis (RA) because of osteopenia and deformities. This study describes a new surgical technique for arthrodesis in painful valgus deformity of the hind-foot in advanced rheumatoid arthritis (RA) with severe osteopenia. MATERIALS: The present series included 9 patients. Eleven talocrural and talocalcaneal arthrodeses were performed for degenerative changes secondary to RA involving hind-foot joints. All patients were reviewed after an average follow-up of 6 years. Mean duration of RA was 34 years. All patients had severe osteopenia, including major deformations of the hind-foot in 5 cases. METHODS: After removal of talocrural and talocalcaneal articular surfaces using an anterolateral approach, deformities were corrected by removal of an appropriate bone wedge. A Küntscher nail was then positioned in the calcaneal plantar cortical through the plantar surface of the foot and driven proximally into the medullary canal of the tibia through the talus. This nail allowed both deformity correction and fixation. Aftercare required immobilization in a short leg cast. Weight bearing was allowed with the cast approximately 5 weeks after surgery. The ankle was immobilized for 7.5 weeks. DISCUSSION: Results showed a 80 per cent fusion rate. Two non-unions occurred (one recurrence of valgus deformity after early nail migration requiring removal of the nail; and the other asymptomatic). A complication occurred in one foot (delayed healing). At follow-up, all patients but one were satisfied with respect to pain relief and residual deformities. Our results are comparable with those of other series and should be considered in the context of severe RA. CONCLUSION: This technique of vertical retrograde transarticular nailing allows an easy control of hind-foot deformities correction. Other techniques are preferable in case of solid bone. This technique is an acceptable alternative in advanced RA.

Adult↗

[Effects of intravenous immunoglobulins in thrombopenia related to septic shock].

OBJECTIVES: Intravenous immunoglobulins have been shown to be effective in the treatment of immunologically mediated thrombocytopenia. Several articles have been published on the positive effect of immunoglobulins in sepsis-related death. We retrospectively studied the effects of intravenous immunoglobulins used during septic shock thrombocytopenia over a 5-year period in a polyvalent intensive care unit. PATIENTS AND METHODS: Inclusion criteria were development of acute thrombocytopenia under 75 G/l during septic shock, excluding all cases of disseminated intravascular coagulation. Thirty-five patients were included in the study; 18 were given polyvalent intravenous immunoglobulins (group IgIV) and 17 were not (controls). The two groups were comparable for SAPS and APACHE II gravity scores at admission and at day 0 (first day of septic shock with platelet count under 75 G/l), age, sex, platelet count at admission, OSF score, type of referral unit, McCabe score, and the presence of 4 parameters which might affect platelet count hemofiltration, ARDS, surgery, Swan-Ganz catheter. RESULTS: Platelet counts increased on day 8 in the treatment group (63.5 G/l, range 25-453 versus 105.7 G/l, range 38-355; p = 0.0505). The number of days with thrombocytopenia was the same in both groups. Overall mortality was high (60%) but there was a difference between the two groups in favor of the treated group (74.7% versus 44.4%; p = 0.053). The number of red cell units (214 vs. 164) and plasma units (175 vs. 54) transfused was higher in the control group. Platelet transfusion was equivalent in the two groups. DISCUSSION: Although we were unable to demonstrate a significant difference in the effects of immunoglobulins on platelet level and mortality, the trend during this evaluation was comparable with that reported in the literature. For transfusion, and although the results were not significant, a notion of reduced risk was evident. Prospective trials are needed to confirm these observations.

Acute Disease↗