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M Julien

Publications and source records attributed to M Julien.

At least 19 recordsLinked to original sources
PubMed1997

12-O-tetradecanoylphorbol-13-acetate inhibits aminophospholipid translocase activity and modifies the lateral motions of fluorescent phospholipid analogs in the plasma membrane of bovine aortic endothelial cells.

The tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) is a potent mitogenic factor which can replace the growth promoting activity of basic fibroblast growth factor (bFGF) on bovine aortic endothelial cells. However, TPA-treated cells lose their strict contact inhibition at confluence, which is a characteristic of cells grown in the presence of bFGF. We have examined whether these changes could be related to modifications of the transbilayer and lateral motions of fluorescent lipids, namely 1-acyl-2-[6-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]caproyl]-p hosphatidylcholine (C6-NBD-PC), -phosphatidylserine (C6-NBD-PS), and -phosphatidylethanolamine (C6-NBD-PE) inserted in the outer leaflet of the cell plasma membrane. In TPA-treated cells, the three fluorescent phospholipids remained located in the outer leaflet for at least 1 h at 20 degrees C after their insertion, indicating a blockade of the aminophospholipid translocase activity which is normally present in the plasma membrane of bFGF-treated cells. TPA also induced a large increase in the percentage of C6-NBD-PC and C6-NBD-PE probes which were free to diffuse laterally. The mobile fractions M reached values of approximately 100% for the two lipids, while for bFGF-treated cells they were found around 85 and 75%, respectively. For the C6-NBD-PS probe, M remained unchanged in bFGF and TPA-treated cells, at around 85%. TPA treatment also induced a twofold increase in the lateral diffusion coefficients of C6-NBD-PC and C6-NBD-PE, while that of C6-NBD-PS remained nearly unchanged. These effects of TPA may be related to the observed loss of differentiated properties of vascular endothelial cells and not to its mitogenic properties.

4-Chloro-7-nitrobenzofurazan↗
PubMed1997

Factors influencing long-term survival in 100 cases of small intestine primary adenocarcinoma.

BACKGROUND: Factors influencing long-term survival in patients undergoing operation for adenocarcinoma of the small intestine are poorly recognized. METHODS: Retrospective study of 100 cases culled within a 10-year period by questionnaire, including 59 males and 41 females, median age 61 years (range 30 to 86). No patients were lost to follow-up (median 27 months). All patients underwent operation: curative in 65% and palliative in 35%. RESULTS: Overall actuarial 5-year survival was 38%, 0% after palliative treatment and 54% after curative resection. In patients undergoing curative resection, 5-year survival was 63% when the lymph nodes were not involved, and 52% when they were; 57% when the serosa was not involved, and 53% when it was; 56% when the tumor was well or moderately well differentiated and 40% when it was undifferentiated. Other factors influencing long-term survival were the emergency setting, the site, the multiplicity, and the size of tumor (none with statistically significant differences). Five and 10-year survival was 78% and 69%, respectively, when the patient was anemic compared with 35% and 17%, respectively when the patient was not (P <0.01). There were 14 patients with previous carcinoma, 2 with Crohn's disease, and 1 each with celiac disease and ileal tuberculosis. There were also 8 patients with associated duodenal and proximal jejunal polyps. Thirteen patients sustained a total of 14 further cancers. CONCLUSIONS: Patients should be followed up closely because the possibility of sustaining another abdominal carcinoma is high (16%). As associated polyps are nearly always duodenal or jejunal, preoperative or intraoperative endoscopy of the upper gastrointestinal tract including the initial portion of the jejunum should be able to detect their presence and reduce the risk of early recurrence.

Actuarial Analysis↗
PubMed1997

Shelf-life of bioprosthetic heart valves: a structural and mechanical study.

This study was undertaken to evaluate the influence of storage conditions on the shelf-life of porcine bioprosthetic valves. Fifty-five unimplanted porcine bioprostheses have been evaluated. The valves were stored in 0.5% buffered glutaraldehyde solution for different periods of time (7, 23 and 32 months). Twenty-eight valves were refrigerated while the remaining valves were stored at room temperature. The pH of the glutaraldehyde solution at room temperature decreased with time of storage, while that kept in the refrigerator remained stable over the course of the study. Macroscopic observations showed that the valve tissues kept at room temperature, especially for the periods of 23 and 32 months, became darker and more yellow in colour, whereas the refrigerated specimens exhibited no such changes in appearance. Scanning electron microscopy analysis revealed no noticeable differences on the surfaces of the leaflets stored under different conditions. Mechanical tests, including stress-strain response, stress relaxation and fracture behaviour, were carried out. Analysis of variance showed that the storage temperature, but not the length of storage, had a significant effect on some mechanical properties. The stress relaxation at 1000 s (P = 0.05), the ultimate tensile strength (P = 0.01) and the strain at fracture (P = 0.04) were all higher after storage at room temperature compared to the results after refrigeration. No statistically significant changes in the denaturation temperature of the collagen were observed between the different storage conditions. In conclusion, the storage temperature appears to have some influence on the bioprosthetic tissue. The bioprostheses stored under ambient conditions experience changes which may influence their longterm in vivo performance.

Animals↗
PubMed1997

Are intraaortic balloons suitable for reuse? A survey study of 112 used intraaortic balloons.

To assess the safety of reusing single-use intraaortic balloon devices (IABs), 112 used devices were investigated in terms of physical integrity, gas leakage inspection, mechanical performance, surface chemistry and morphology, and physical stability. These IABs were all used clinically only once, and the duration of the IABs in vivo ranged from 6 to 312 h. Macroscopic examination of the balloons and the outer catheters revealed no obvious change in either shape or color. No discernible abrasions or cracks were observed on the balloons. However, 61% of the balloons were creased, and 40% of the central lumens and 21% of the sheaths showed visible bending flaws. Moreover, 65% of the balloons and 38% of the central lumens were contaminated by visible residual organic debris. The physical integrity of each device was verified in a specially designed leakage-fatigue tester for 72 h. Ninety-seven percent of the devices passed the leakage inspection. Stress-strain testing, differential scanning calorimetry, attenuated total reflection-Fourier transform infrared, and scanning electron microscopy analyses clearly indicated that there were no significant differences in the mechanical properties, bulk material morphology, surface chemistry, and external surface morphology between the used balloons and virgin controls. Although some surface modifications occurred on the internal side of the balloons, the external surfaces of most balloons suffered no trauma. Most of the used IABs examined in this study maintained physical and mechanical properties similar to those of the virgin devices. The chemistry of the balloon material was stable after short-term in vivo use. However, it does not seem possible to establish a rigorous protocol of cleaning, sterilization, and inspection to guarantee a safer reuse of these devices. The presence of residual organic debris that cannot be eliminated results in an imperative preclusion not to reuse the IABs.

Calibration↗
PubMed1997

[Lingual thyroid and intra-lingual thyroglossal cyst. Apropos of 2 cases].

Lingual thyroid and intra lingual thyro-glossal cyst are two benign tumours of similar embryological pathogenesis respectively with the arrest in the ectopic position of the thyroid gland during its downward migration and from abnormal persistence of the thyro-glossal tract for the cyst. The occurrence of lingual thyroid is rare 1/100,000 patients and outnumbers the incidence of intra-lingual cyst which represents an estimated 2.1% of the thyro-glossal cysts or fistulas. Both lesions are a rare cause of dysphagia and dyspnoea due to oropharyngeal obstruction, and radionuclide scintigraphy combined with CT and/or MRI will establish the diagnosis. Surgical pharyngotomy with an infra-hyoid approach provides excellent access to the lesions and complete removal of the tumours.

Adolescent↗
PubMed1996

The MAN antigens are non-lamin constituents of the nuclear lamina in vertebrate cells.

The characterization of the human antiserum designated MAN has led to the identification of a subset of non-lamin proteins that are exclusively located at the nuclear periphery in all vertebrate cell types examined, from human to fish. Immunoreactive protein species were shown to comprise three major polypeptides of Mr 78000, 58000 and 40000. These antigens co-partitioned with the nuclear lamina during in situ isolation of nuclear matrices from lamin A/C-positive and -negative mammalian cells. Using double immunofluorescence, the spatial relationship of MAN antigens to type-A and type-B lamins was further examined throughout the cell cycle of lamin A/C-positive mammalian cells. In interphase HeLa and 3T3 cells, MAN antigens colocalized with both types of lamins at the periphery of the nucleus, but were absent from intranuclear foci of lamin B. As HeLa cells proceeded into mitosis, MAN antigens were seen to segregate from lamins A/C and coredistribute with lamin B. Lamins A/C disassembled during late prophase/early prometaphase and reassociated with chromatin in telophase/cytokinesis. In contrast, MAN antigens and lamin B dispersed late during prometaphase and reassembled on chromosomes in anaphase. Altogether, our data suggest that MAN antigens may play key functions in the maintenance of the structural integrity of the nuclear compartment in vertebrate cells.

3T3 Cells↗
PubMed1996

[Limitation of blood transfusions during hepatectomies. Study of 150 consecutive hepatic resections on healthy and pathological livers].

OBJECTIVE: Over the last 5 years, a policy to limit blood transfusions has been adopted in patients undergoing liver resection. The aim of this retrospective study was to report the results of 150 liver resections performed during this period. METHODS: There were 63 major (42%) and 87 minor hepatectomies (58%). Resection was performed for malignant lesions in 64% of the patients. Vascular exclusion of the liver was used in large (> or = 10 cm) tumors and those located at the cavohepatic junction. Clamping of the portal triad or selective clamping of the pedicle of the portal lobe was used in peripheral lesions < 10 cm in diameter. Anesthesia was adapted to the type of vascular clamping and blood transfusions were deliberately limited. Red blood cells were transfused to maintain the hematocrit level above 25% in healthy patients and above 30% in patients with risk of coronary artery disease. RESULTS: Ninety three patients (62%) did not receive blood transfusions. Three patients received more than 10 units of packed red blood cells (2%). 48% of patients with major hepatectomies and 72% with minor hepatectomies were not transfused. The rate of non transfused patients was 93% for benign lesions and 44% for malignant lesions. The presence of pathologic changes in non-tumor liver parenchyma did not influence the need for transfusions. Hospital mortality was 3% (5/150). There was no mortality in patients with normal non-tumorous livers, 14% in the presence of cirrhosis, and 12% in the presence of obstructive jaundice or steatosis > 50%. The specific morbidity rate was 7% in patients with normal livers and 54% in patients with abnormal livers. CONCLUSION: This series shows that more than 60% of liver resections can be performed without blood transfusions. These results require an appropriate surgical technique and collaboration between anesthesiologist and surgeon. Thus hepatectomies in normal non-tumorous livers can be performed without mortality. In contrast, the presence of abnormalities of the non-tumorous liver parenchyma remains a major risk factor.

Adult↗
PubMed1996

[Osteoma of the mastoid: apropos of 2 cases].

The authors report two cases of mastoid osteoma: it is a rare benign tumor attached to the cortex of the mastoid bone, approximatively fifty cases have been described in the english language literature and eight in the french literature. The clinical and radiological characteristics combined with histopathologic evidence demonstrate the diagnosis of mastoid osteoma, the most common type being the compact osteoma. Differential diagnosis should be considered with others benign bone-forming lesions (osteochondroma, chondroma, osteoblastoma, exostosis, fibrous dysplasia...) and with malignant lesions (osteosarcoma...). Surgical removal proposed for cosmetic deformity is a simple procedure for the vast majority of small osteomas. Early surgical intervention is recommended to avoid the evolution toward giant osteoma with potential risks of surgical complications.

Adult↗
PubMed1995

Basic fibroblast growth factor modulates the aminophospholipid translocase activity present in the plasma membrane of bovine aortic endothelial cells.

Vascular endothelial cells form the inner nonthrombogenic lining of the large blood vessel. Through back-exchange and fluorescence recovery after photobleaching experiments and using the two fluorescent lipids 1-acyl-2-[6-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino] hexanoyl]glycerophosphocholine and 1-acyl-2[6-N-(7-nitrobenz-2-oxa-1, 3-diazol-4-yl)amino]hexanoyl]glycerophosphoethanolamine, we have recently shown that an energy-dependent and protein-dependent aminophospholipid translocase activity is present in the plasma membrane of cultured bovine aortic endothelial cells, which specifically transports phosphatidylethanolamine from the outer leaflet toward the inner leaflet of the membrane lipid bilayer. In the present study, using the same approach and 1-acyl-2-[6-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]hexanoyl] glycerophosphoserine as the probe, it is shown that this conclusion is also valid for phosphatidylserine. Furthermore, evidence is presented indicating that this aminophospholipid translocase activity can be maintained, suppressed, and restored at will, depending on the conditions of cell incubation. Thus, the translocase activity is detected for cells maintained in their normal culture medium or in a serum-free incubation medium [Dulbecco's modified Eagle's medium (DMEM)] supplemented with the basic fibroblast growth factor, whereas inhibition is observed for cells exposed for at least 2 h to DMEM. The translocase activity is restored when these pretreated cells are further incubated at least for 1 h in the presence of serum or of basic fibroblast growth factor. In view of the importance of basic fibroblast growth factor as a mitogenic and differentiating agent for vascular endothelial cells, various growth factors were tested (acidic fibroblast growth factor, epidermal growth factor, platelet-derived growth factor, transforming growth factors alpha and beta, vascular endothelial growth factor, interferon gamma, tumor-necrosis factor, insulin, and interleukin 4). Only basic fibroblast growth factor was active in the maintenance and restoration of the translocase activity. With respect to the effects of serum, evidence is presented showing that high-density lipoproteins might play a role in the control of the translocase activity. However, the positive effects of basic fibroblast growth factor, serum and high-density lipoproteins on the translocase activity were suppressed when experiments were carried out in the presence of an anti-(basic fibroblast growth factor) IgG, thus indicating that in all cases, basic fibroblast growth factor was directly involved in the modulation of the aminophospholipid translocase activity present in the plasma membrane of bovine aortic endothelial cells.

Adenosine Triphosphate↗
PubMed1995

Intrahepatic cholangiocarcinoma. Results of aggressive surgical management.

OBJECTIVE: To report the results of a deliberately aggressive surgical management in patients with intrahepatic cholangiocarcinoma. DESIGN: A case series of patients with intrahepatic cholangiocarcinoma. SETTING: A tertiary care university hospital in a metropolitan area. PATIENTS: From 1989 to 1993, 19 patients with intrahepatic cholangiocarcinoma underwent laparotomy, with a 74% resectability rate (14 liver resections). In addition, two selected patients with a slow-growing tumor underwent orthotopic liver transplantation after limited recurrence following resection in one case and after exploratory laparotomy in the other. INTERVENTIONS: The 14 liver resections included six right or left hepatectomies and eight extended right or left hepatectomies. Total vascular exclusion of the liver was used in nine cases (64%) and resection of the biliary confluence with reconstruction was used in six cases (43%). RESULTS: There was one postoperative death (7%). There were four postoperative biliary fistulas (28%). Overall actuarial 1- and 2-year survival rates were 58% and 32%, respectively. The 1- and 2-year survival rates were 100% after curative resection (no lymph node invasion, clearance margin of < or = 1 cm, and solitary tumor [five cases]) and 48% and 10% after palliative resection. Median survival was 14 months for the whole series and 27 and 9 months following curative and palliative resections, respectively. The two liver transplant recipients are alive and free of disease at 25 and 31 months. CONCLUSION: These results support aggressive surgical management in patients with intrahepatic cholangiocarcinoma, including complex liver resection procedures and selective use of orthotopic liver transplantation.

Actuarial Analysis↗
PubMed1995

Characterization of the 2H12 antigen as a nonshuttling human isoelectric variant of the nucleolar protein B23.

It has become obvious that a better understanding of the nucleolar compartment should encompass the elucidation of structural and functional relationships between its molecular constituents. Using a mouse monoclonal antibody referred to as 2H12, we have identified a human epitope that appears to be implicated in the regulatory events governing the elaboration and stabilization of the nucleolar architecture. By immunofluorescence and immunoblotting, the 2H12 monoclonal was shown to be directed against a nucleolar protein with a relative mobility of 38-40 kDa and an isoelectric point of 5.1 that is present in human cells, regardless of their proliferation state. No reactivity was detected in cells from other species, implying that the targeted epitope could be unique to humans. Investigation of the fate of the epitope throughout the cell cycle led to evidence that its immunoreactivity was phosphodependent and suggested that the disassembly and reassembly of the nucleolar apparatus during cell division is accompanied by dephosphorylation/phosphorylation modifications at this site. In a series of double immunofluorescence experiments and two-dimensional immunoblotting analyses, it was demonstrated that the 2H12 antigen corresponds to an isoelectric variant of the human nucleolar protein B23 that is most prominent during interphase. Tightly associated with the nuclear matrix, this human B23 isoelectric variant did not shuttle between the nucleus and the cytoplasm but remained sequestered within the human nucleolus during mobility assays in human-murine heterokaryons.

Animals↗
PubMed1995

Residual organic debris on processed surgical instruments.

This preliminary study describes the degree of cleanliness of three categories of surgical instruments after processing (ie, decontamination, inspection, sterilization). The three categories were reusable laparoscopic, reused disposable laparoscopic, and conventional surgical instruments. The objective of the study was to identify from visual inspection and microscopic examination residual particles, stains, or liquid on processed instruments. The investigators studied 32 instruments selected at random from a hospital's supply of processed surgical instruments. On visual inspection, 90.6% (29/32) of the instruments appeared clean. Microscopic examination with a photomicrographic system, however, revealed residual debris on 84.3% (27/32) of the instruments. The quantity of residual debris on both types of laparoscopic instruments (ie, reusable, reused disposable) was equivalent. The conventional instruments contained less residual debris than the laparoscopic instruments. Sites that contained residual debris included junctions between insulating sheaths and activating mechanisms of laparoscopic instruments and articulations and grooves of forceps. More research is needed to determine the prevalence and clinical significance of these findings.

Alberta↗
PubMed1995

Changing patterns in pediatric mortality, Maputo Central Hospital, Mozambique, 1980-1990.

OBJECTIVES: To present an analysis of the Department of Paediatrics' statistics on hospital mortality, covering the period through 1980-1990. METHODS: Basic information was recollected from logbooks of the Department's wards. Descriptive statistics are estimated on death and its main causes. The proportion of deaths in relation to total admissions and in relation to global in-hospital mortality are computed and their changes over time documented. RESULTS: The data show an important decrease of in-hospital global mortality in spite of the increase of the number of admissions over time. The pattern of the main causes of death changed, and the authors postulate that the change is attributed to a dramatic change in the epidemiological pattern of childhood morbidity in Maputo City, especially due to measles vaccination. In parallel, the study suggests an increase in the prevalence of severe malnutrition. CONCLUSIONS: Hospital statistics, while dependent on socio-economic conditions, can be significantly changed by Public Health interventions. Monitoring and analysing hospital statistics is important for documenting epidemiological changes, and also to suggest community interventions. From that point of view, epidemiological surveillance and hospital statistics are complementary.

Child↗
PubMed1995

[Surgical treatment of severe ulcerous hemorrhages: predictive factors of operative mortality].

OBJECTIVES: Multivariate analysis of operative mortality in patients with bleeding peptic ulcer. METHODS: Seventy-eight consecutive patients, who underwent emergency surgical treatment for bleeding peptic ulcer were reviewed retrospectively. There were 49 males and 29 females, with a mean age of 64.3 years, 2/3 of whom had associated medical disease. Surgical treatment was conservative in 63 cases: oversewing or ulcer excision, alone (n = 29) or associated with vagotomy (n = 34); and was radical in 15 cases: antrectomy+vagotomy (n = 10) or partial gastric resection (n = 5). RESULTS: There were 17 (21.8%) postoperative deaths and 19 (24.3%) bleeding recurrences. The causes of death included 9 bleeding recurrences, 7 organ failures and one duodenal leakage. On multivariate analysis, previous medical illness (cirrhosis or cardiac insufficiency (P < 0.001), shock at admission (P < 0.001), prolonged delay until surgery (P < 0.001), and bleeding recurrence (P < 0.001) were independently associated with increased mortality. In contrast, the type of surgical procedure did not influence postoperative mortality, whereas bleeding recurrence was more frequent in case of conservative surgery (P < 0.03) and anticoagulation therapy (P < 0.01). CONCLUSION: These results suggest that surgical treatment of bleeding peptic ulcer should be proposed early in high-risk patients. A radical procedure should be favoured since it reduces bleeding recurrence rate without increasing operative mortality.

Adult↗