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D Gaillard

Publications and source records attributed to D Gaillard.

At least 55 records · Page 3Linked to original sources
PubMed1997

[Vitamin-resistant rickets cured by removal of a bone tumor. Review of the literature].

PURPOSE OF THE STUDY: Rickets secondary to bone or soft tissue tumors are rare in children. Majority of the reported cases occurred in adults older than thirty. This entity can be cured after tumor removal. The authors present a case in a ten year boy and literature review. MATERIAL: A ten year boy complained of diffuse bone and muscle weakness for two years. A diagnosis of arthritis was made but the patient continued to complain. Serum calcium level was normal (2.33 mmol/l), phosphorus was very low (0.43 mmol/l), serum alkaline phosphatase was high, parathyroid hormone and vitamin D level were normal. Urinalysis showed abnormal phosphate excretion. METHODS: The absence of malabsorption, no family history of rickets or hypophosphatermy presence of a marked excess of urinary phosphate, very low serum phosphate and normal serum calcium, vitamin D and parathyroid hormone levels led us to consider a diagnosis of tumor induced osteomalacia. Radiographs showed a large round radiolucent lesion in the left superior pubic ramus and generalized demineralisation. RESULTS: We performed a complete tumor resection and the space was filled with bone graft. On histopathologic examination it was a benign mesenchymal tumor. Rapid reversal of biochemical anomalies, radiographs anomalies and clinical manifestation were observed after complete tumor resection. DISCUSSION: The authors have described the tumor, the osteomalacia and the pathogenesis of tumor rickets. Histologically the most common causative tumors were vascular tumors, mesenchymal tumors and non ossifying tumors. The tumor were of bone or soft tissue origin. Clinical symptoms were muscular weakness, bone and muscle pain. Biochemically there is a very low phosphate level, a normal serum calcium level as well as a normal vitamin D and PTH level. There is a significant high level of urinal phosphate. The mechanism proposed to explain oncogenic osteomalacia includes tumor secretion of phosphaturic substance other than PTH and calcitonin. Another hypothesis is a substance interfering with normal vitamin D metabolism. The pathogenesis is not clearly defined. CONCLUSION: Regardless to the mechanism of osteomalacia, complete removal of the tumor will cure the patient. A diligent search for tumors should be done in patients with vitamin D resistant rickets.

Bone Neoplasms↗
PubMed1996

Changes in adenosine A1- and A2-receptor expression during adipose cell differentiation.

Two adenosine receptors A1 and A2 are associated with either stimulation (A2) or inhibition (A1) of adenylate cyclase. Using the clonal cell line Ob1771, we have studied the expression of the two receptors during the process of adipose conversion accelerated by exposure to dexamethasone and 3-isobutyl-l-methylxanthine (IBMX) during the first 3 days post-confluence. The effects mediated by the two receptors on preadipocyte differentiation and adipocyte metabolism were also investigated. The two adenosine agonists NECA and PIA were used as preferential agonists of the A2- and A1-receptor, respectively. In preadipose cells (just confluent), both of the mouse clonal line and human primary culture, NECA dose-dependently stimulated cAMP production with a significant higher potency (P < 0.01) than did PIA. In adipose cells (16-day post-confluent) NECA was found to exert a biphasic effect on forskolin-stimulated cAMP production: i.e., NECA was clearly inhibitory in the femto- to picomolar concentration range whereas this effect gradually diminished at higher concentrations. The effect of PIA in 16-day post-confluent adipose cells however, was purely inhibitory on both cAMP production (IC50: 33.52 +/- 0.44 fM) and lipolysis (64% +/- 7%; P < 0.01). These findings were corroborated by Northern blot analysis which revealed A1-receptor mRNA to be exclusively expressed in the mature adipocytes, whereas A2-receptor mRNA gradually declined during the differentiation process except in 16-day post-confluent cells. In addition, NECA significantly enhanced the effect of corticosterone-induced differentiation by 46.8% (P < 0.05) but failed to have any adipogenic potency acting either alone or in concert with carbaprostacyclin (cPGI2). Thus, endogenous adenosine may have a bimodal action on adipose tissue metabolism mediated through stimulatory A2- and inhibitory A1-receptors, respectively, as a function of adipose conversion.

1-Methyl-3-isobutylxanthine↗
PubMed1996

Fryns syndrome phenotype and trisomy 22.

Trisomy 22 was detected in a 32-week-old fetus born to an overweight mother with hypertension. Severe intrauterine growth retardation was associated with phenotypic manifestations of Fryns syndrome: diaphragmatic hernia, facial defects, and nail hypoplasia with short distal fifth phalanges. This is the second report of congenital diaphragmatic hernia in trisomy 22. This case demonstrates the importance of karyotyping malformed fetuses or newborns, even if a nonchromosome syndrome seems identifiable on clinical grounds. To date, at least 10 cases of Fryns syndrome have been reported without chromosome analysis.

Adult↗
PubMed1996

Effects of two different crystalloid cardioplegic solutions assessed by myocardial pH, tissue lactate content and energy metabolism.

OBJECTIVE: The influence of composition of crystalloid cardioplegia is imprecise in clinical practice. Therefore, we investigated changes in intramyocardial pH, tissue lactate content and energy metabolism during cardioplegic arrest with 2 different crystalloid cardioplegic solutions. METHODS: Twenty patients were randomly allocated to 2 groups: 10 patients had crystalloid cardioplegia buffered with bicarbonate (neutral pH of 7.8 at 20 degrees) with no additives (St Thomas' II solution) and 10 patients had a non buffered crystalloid cardioplegia (mildly acidic pH of 7.4 at 20 degrees) enriched with glutamate and mannitol (Menasché's solution). Tissue lactate and energy metabolism were measured on myocardial biopsy specimens and intramyocardial pH were continuously measured during cardioplegic arrest by a miniature glass electrode. RESULTS: There were no statistical differences in hemodynamic results and in AMP, ADP, ATP, lactate values measured on biopsy specimens. The curves of intramyocardial pH were very similar in the 2 groups, the median values were 7.42 +/- 0.1 in group 1 and 7.41 +/- 0.1 in group 2 (temperature corrected values) and the areas under the curves were 260 +/- 4 and 259 +/- 4 in groups 1 and 2 respectively (P = NS). CONCLUSIONS: Glutamate provided no additive metabolic myocardial protection, bicarbonate had a weak buffering capacity in cold cardioplegic solutions and the 2 studied crystalloid solutions warranted a good myocardial protection in clinical practice.

Acid-Base Equilibrium↗
PubMed1996

Bilateral skeletonized mammary artery grafting: experience with 560 consecutive patients.

OBJECTIVE: To test the hypothesis that the skeletonized technique of harvesting the internal thoracic artery improves the surgical results of bilateral internal thoracic artery grafting, we reviewed our 7-year experience with this technique. METHODS: Between July 1987 and December 1994, 560 patients received bilateral internal thoracic artery grafts and 236 additional grafts (average 2.6 +/- 0.6 anastomoses per patient). There were 515 men (92%) and the average age was 56.9 +/- 8.8 years. There were 63 diabetic patients (11.3%). During harvesting, the internal thoracic arteries were always totally skeletonized from the surrounding tissues without the use of electrocautery. RESULTS: Postoperative complications included reoperation for bleeding, 17 patients (3%), phrenic nerve paresis, 17 patients (3%), acute respiratory distress syndrome, 9 patients (1.6%), digestive complications, 8 patients (1.4%), neurologic complications, 6 patients (1.1%), and sternal complications, 6 patients (1.1%). No wound complications were observed in diabetic patients. The hospital mortality rate was 1.6% (9 patients, 2 cardiac causes). The early patency of internal thoracic artery grafts was 97.9%. Follow-up averages 29 +/- 20 months. There were 14 late deaths (4 cardiac causes). Angina recurred in 51 patients and the maximal stress test was abnormal in 47 patients. CONCLUSION: Bilateral internal thoracic artery grafting with skeletonized harvesting carried low post-operative mortality and morbidity and therefore it could be applied routinely without the fear of increased complication rate.

Adult↗
PubMed1996

Expression and localization of epidermal growth factor, transforming growth factor-alpha, and localization of their common receptor in fetal human lung development.

Transforming growth factor-alpha (TGF-alpha), epidermal growth factor (EGF), and their common EGF receptor have been shown to be involved in cell proliferation and lung maturation. The aim of the study was to determine the site of production of TGF-alpha and EGF mRNA and the cellular distribution of TGF-alpha/EGF proteins and EGF receptor, in fetal human lung. By using in situ hybridization with 35S-labeled cDNA probes in frozen sections from eight lungs from fetuses ranging from 12 to 33 wk of gestation, TGF-alpha and EGF mRNA transcripts appeared to be confined to the mesenchymal cells and mainly found in the dense connective tissue along the pleura, bronchi, and large vessels, but undetected in bronchial epithelial cells. The streptavidin-biotin immunoperoxidase method, applied to paraffin-embedded specimens from 39 fetuses ranging from 10 to 41 wk, showed that TGF-alpha, EGF, and EGF receptor exhibited a similar cellular distribution during the whole period of gestation. They were detected in the undifferentiated cells of the airway surface epithelium, mesothelial cells, smooth muscle, and a few mesenchymal cells, as early as 10 wk. After 12 wk, the immunoreactivity was strong in the ciliated, secretory, and basal cells, and in growing glands along the large airways, but proved lower in the distal airways. After 24 wk, the immunoreactivity remained in the airway epithelium, but was mainly localized in the apical domain of ciliated cells, in alveolar cells, and in the serous cells of the glands. The presence of TGF-alpha, EGF, and EGF receptor during the whole period of fetal lung development suggests that these factors are not only mitogenic, but can also be involved in epithelial maturation, through paracrine secretion, as most TGF-alpha and EGF mRNA transcripts are expressed in mesenchymal cells.

Antibody Specificity↗
PubMed1995

Thiazolidinediones and fatty acids convert myogenic cells into adipose-like cells.

Fatty acids and thiazolidinediones act as potent activators of the adipose differentiation program in established preadipose cell lines. In this report, the effects of these agents on the differentiation pathway of myoblasts have been investigated. Exposure of C2C12N myoblasts (a subclone of the C2C12 cell line) to thiazolidinediones or fatty acids prevents the expression of myogenin, alpha-actin, and creatine kinase, thus abolishing the formation of multinucleated myotubes. These treatments lead in parallel to the expression of a typical adipose differentiation program including acquisition of adipocyte morphology and activation of adipose-related genes. A similar transition toward the adipose differentiation pathway also occurs in mouse muscle satellite cells maintained in primary culture. Thiazolidinediones exert their adipogenic effects only in non-terminally differentiated myoblasts; myotubes are insensitive to the compounds. Continuous exposure to inducers after growth arrest is not required to maintain the adipose phenotype, but proliferation of adipose-like C2C12N cells leads to a complete reversion toward undifferentiated cells able to undergo either myogenic or adipogenic differentiation depending on the composition of culture medium. These results indicate that adipogenic inducers, such as thiazolidinediones or fatty acids, specifically convert the differentiation pathway of myoblasts into that of adipoblasts.

5,8,11,14-Eicosatetraynoic Acid↗
PubMed1995

Determination of reliable histological features associated with early triploidy using DNA image cytometry.

In order to determine reliable histological features characterizing triploidy, the following features were examined and graded by three pathologists on 46 early abortion specimens: hydropic swelling of the villi, cisterns, villous scalloping, trophoblastic hyperplasia with syncytial vacuolization, single cytotrophoblastic cells in villous stroma, trophoblastic inclusions, microcalcifications and fibrosis. At the same time, the DNA content of the 46 specimens was quantified cytophotometrically using the CAS 200 image analyzer, in order to confirm or not the diagnosis of triploidy. Triploidy was confirmed in 45.7%, and in the triploid group, the grading of three features differed significantly from the non triploid group i.e. cisterns (p < 0.001), trophoblastic hyperplasia (p < 0.05) and trophoblastic inclusions (p < 0.05). Using these three features we were able to give a triploid score per slide which represents the sum of the grades of each of these three features. The minimum score obtained was 0, the maximum was 6. The average of these scores in the triploid group was 3.095, and 1.45 in the non triploid group (p < 0.001). This scoring method on the three significant features (cisterns, trophoblastic hyperplasia and trophoblastic inclusions) appears to be useful to classify an abortion specimen as triploid or not, and to select the specimens for which a DNA quantification may be necessary.

Abortion, Spontaneous↗
PubMed1995

[Sirenomelia. Review of nosology and a case report].

We report a case of sirenomelus observed at 21 weeks amenorrhoea with oligoamnios. This syndrome results from an anomaly during the fourth week of gestation perturbing development of the lower limbs and the pelvis. Normal differentiation of the sexual organs, urinary tract and terminal intestine is interrupted. Recent progress in embryopathology has led to identification of a caudal regression syndrome but the aetiology remains unknown as is the nature of the relationship with VATER association.

Abortion, Therapeutic↗
PubMed1994

Proliferation and differentiation of rat adipose precursor cells in chemically defined medium: differential action of anti-adipogenic agents.

Primary rat adipose precursor cells, maintained in the minimal chemically defined medium (ITT medium) able to promote differentiation, have been used to investigate the ability of several agents to modulate their proliferation and their differentiation. Fetuin and fibroblast growth factor (FGF), which exhibited a strong and a weak mitogenic activity, respectively, do not significantly affect the proportion of differentiated cells as indicated by glycerol-3-phosphate dehydrogenase (GPDH) activity values. In contrast, carbaprostacyclin (cPGI2), a stable analogue of prostacyclin, behaves as a true adipogenic factor leading to a 4 to 5-fold increase in GPDH-specific activities with no significant effect on cell growth. Submaxillary gland kallikrein (SMGK), transforming growth factor-beta (TGF-beta) and tumor necrosis factor-alpha (TNF-alpha) behave as growth-promoting agents but at the same time elicit a dose-dependent inhibition of differentiation. Epidermal growth factor (EGF) and prostaglandin F2 alpha (PGF2 alpha) do not show any effect on cell proliferation at concentrations which exert a maximal inhibitory action on differentiation. Upon removal of EGF from the culture medium, complete resumption of differentiation occurs, whereas upon removal of PGF2 alpha or SMGK, complete resumption only takes place when differentiation is triggered by cPGI2. Upon removal of TNF-alpha, a partial resumption of differentiation is observed, whereas no subsequent differentiation is observed upon TGF-beta removal. These results emphasize the adipogenic, nonmitogenic role of cPGI2 and also allow the distinction between the various adipogenic/mitogenic factors which affect adipose cell differentiation.

Adipocytes↗
PubMed1994

Glandular-like morphogenesis and secretory activity of human tracheal gland cells in a three-dimensional collagen gel matrix.

The extracellular matrix has been demonstrated to affect the differentiation of epithelial cells. We present evidence that in a three-dimensional (3-D) type I collagen gel matrix, isolated human adult tracheal gland (HTG) cells are capable of reconstructing new functional gland-like tubules in vitro. During the first two weeks in culture, HTG cells developed globular epithelial cell aggregates in which lumina is absent. By the third week in culture, the tubulogenesis and the formation of branching structures became evident with a polarized morphology, which in many aspects resembles the in vivo morphology. A central lumen was lined by polarized secretory epithelial cells exhibiting well-developed microvilli and apical secretory granules. Furthermore, we showed that the capacity of in vitro tracheal gland differentiation was associated with the basal deposition of laminin and type IV collagen around the gland-like tubules. A cell-associated 72 kDa type IV collagenase was expressed in developing tubule cells, as shown by immunocytochemistry. The secretion of the antileucoprotease (ALP), a protein marker of tracheal gland serous cells, was bidirectional in gland-like tubules, since up to 65% of released ALP was in the basolateral direction. Taken together, these observations indicate that isolated HTG cells in a 3-D collagen matrix form functional tracheal gland-like tubules and suggest that similar new tracheobronchial gland formations may occur during the human normal gland development and remodeling.

Cell Differentiation↗
PubMed1994

Gene transfer to human fetal pulmonary tissue developed in immunodeficient SCID mice.

Human fetal lung rudiments (8-12 weeks of development) undergo considerable growth upon microsurgical ectopic implantation in the xenograft-tolerant SCID mouse, and differentiate into a lung-like tissue that includes: (i) bronchial structures lined with pseudostratified, secretory, ciliated epithelium surrounded by smooth muscle and cartilage rings, (ii) submucosal glands, and (iii) alveolar sacs. Normal expression of the cystic fibrosis transmembrane conductance regulator (CFTR) protein was detected by immunostaining in those grafts, and similar differentiation was observed from either normal or cystic fibrosis (CF) fetal lung rudiments. Upon microinjection into human CF or normal lung grafts in SCID mice, beta-galactosidase-adenovirus gene constructs were efficiently transduced into epithelial and glandular cells. Such an in vivo replica of the human respiratory tissue may be a useful experimental model to study normal and pathologic lung development, and to assay candidate therapeutic gene constructs preclinically.

Adenoviridae↗
PubMed1994

Airway epithelial damage and inflammation in children with recurrent bronchitis.

Inflammation and epithelial damage of the bronchial mucosa are frequently identified in children with bronchial diseases. Nevertheless, until now the quantitative assessment of the epithelial damage has never been studied in relation to clinical or respiratory function or mucus abnormalities. Bronchial biopsies and brushings were performed in 31 children with recurrent bronchitis and without atopia. The quantitative histologic data were compared with clinical results, the endoscopic appearance of the mucosa, ciliary beating frequency, mucus transport capacity, leukocyte count, and protein concentration in mucus samples. Most of the biopsies (87%) collected in this group of children without recent acute infections showed extensive epithelial damage. A significant correlation was observed between the degree of shedding and edema (p < 0.01). Bronchial epithelial edema was associated with a significantly decreased (p < 0.01) mucus transport rate. Inflammation of the submucosa was significantly correlated with lymphocyte epithelial infiltration (p < 0.01), total mucus protein content (p < 0.01), and local airway inflammation estimated by bronchoscopy. These results demonstrate that children with recurrent bronchitis develop a severe bronchial inflammation associated with an increased mucus protein content and a reduction in the mucociliary function.

Biological Transport↗
PubMed1994

Immunohistochemical localization of cystic fibrosis transmembrane conductance regulator in human fetal airway and digestive mucosa.

The cellular distribution of the cystic fibrosis transmembrane conductance regulator (CFTR) in human fetal digestive and respiratory mucosa has been studied by immunohistochemistry. The streptavidin-biotin immunoperoxidase method was applied to paraffin-embedded specimens collected from normal fetuses ranging from 7 to 39 wk of gestation. By the 7th wk, CFTR protein was strongly detected in the yolk sack; in contrast, the staining was weak in the undifferentiated epithelium of the intestine and the airways. At 12 wk, the intestine showed strongly and diffusely stained enterocytes and a basal cytoplasmic reactivity in the first secretory cells. During development, only slight changes could be detected in the digestive epithelial distribution of CFTR. In the airways, the CFTR distribution followed the cephalocaudal maturation. In the tracheal ciliated cells, the CFTR protein was diffusely detected in the cytoplasm as early as 7 wk. After 24-25 wk, CFTR was localized at the apical domain of the ciliated cells and was also present in the collecting ducts and in the glands of the airways, predominantly in the periphery of the acini. Our data suggest that the CFTR is present as early as 7 wk during organogenesis and probably plays an important role during fetal life. There is an evolution in the CFTR distribution during airway development, whereas, in the intestine, CFTR is highly expressed through the epithelium as early as 12 wk and keeps the same distribution until birth.

Antibodies, Monoclonal↗
PubMed1994

Evidence for a common mechanism of action for fatty acids and thiazolidinedione antidiabetic agents on gene expression in preadipose cells.

In diabetic rodents, thiazolidinediones are able to improve insulin sensitivity of target tissues and to reverse, at least partially, the diabetic state. The effects of these drugs on phenotypic expression in various tissues, including adipose tissue, have been reported. We report here that a new thiazolidinedione compound, BRL 49653, exerts, in preadipose cells, potent effects on the expression of genes encoding proteins involved in fatty acid metabolism. These effects of BRL 49653 in Ob 1771 preadipose cells are similar, in terms of kinetics, reversibility, specificity of genes affected, and requirement for protein synthesis, to those already described for natural or nonmetabolizable fatty acids. Moreover, when used at submaximally effective concentrations, BRL49653 and 2-bromopalmitate act in an additive manner to induce gene expression in preadipose cells, but this additivity of effects is lost when one of the compounds is used at a maximally effective concentration. These observations, suggesting similar mechanisms of action for thiazolidinediones and fatty acids, are strongly supported by the demonstration that (i) both molecules activate, in a heterogolous trans-activation assay, the same nuclear receptor of the steroid/thyroid hormone nuclear receptor superfamily and (ii) transfection of 3T3-C2 fibroblasts with an expression vector for this nuclear receptor confers thiazolidinedione inducibility of adipocyte lipid-binding protein gene expression.

3T3 Cells↗
PubMed1994

In situ microdialysis of prostaglandins in adipose tissue: stimulation of prostacyclin release by angiotensin II.

In order to clarify the physiological roles that PGE2 and PGI2, the two major metabolites of arachidonic acid in adipose tissue could play in vivo, their measurements have been undertaken in the interstitial fluid of rat periepididymal adipose tissue using in situ microdialysis. This technique appears suitable with a rather high dialysis yield (70%) for the measurement of prostaglandins. The basal equilibrium extracellular concentrations of 6-keto-PGF1 alpha (the stable metabolite of PGI2) and PGE2 can be estimated to 1 and 0.3 nM, respectively. Experiments designed to study the hormonal regulation of in situ PGI2 and PGE2 production show that (i) lipolysis induced by local perfusion of 10(-6) M isoproterenol is not accompanied by an increase of either 6-keto-PGF1 alpha or PGE2 in the dialysate but, in contrast (ii) perfusion of angiotensin II (10(-7)-10(-5) M) leads, independently of triacylglycerol hydrolysis, to a transient dose-dependent and indomethacin-sensitive increase of released 6-keto-PGF1 alpha with no change in released PGE2. Therefore, in vivo PGI2 appears as the major hormonally regulated prostaglandin in rat adipose tissue, and angiotensin II appears as a physiological effector of its extracellular release.

Adipose Tissue↗
PubMed1994

[DNA quantification and triploidy phenotype in the second and third trimesters of pregnancy].

Triploidy is often associated with early abortions, but may evolve during the second trimester taking a peculiar phenotype. The conditions of diagnosis or abortion do not always let the possibility of karyotyping. Thus, DNA quantification takes all its value. Twenty-three fetuses and placentas, ranging from 14 to 30 weeks of gestation with a phenotype of triploidy were analysed. Twelve cases were proved by karyotype. The DNA index studied in 6 of these was near 1.5, which confirmed the validity of the technique. Out of 11 phenotypes without karyotyping, DNA analysis identified 4 triploidies and a possible tetraploidy. So, a series of 16 cases could be collected, including 10 partial hydatidiform moles and 6 hypotrophic or normal fetuses and placentas.

Adolescent↗