[Preparedness for influenza A/H5N1 pandemic in Niger: a study on health care workers' knowledge and global organization of health activities]. / Pandémie grippale A/H5N1 et niveau de préparation du Niger: une étude sur les connaissances des soignants et l'organisation générale des soins.

In industrialized countries, the emergence of potentially pandemic influenza virus has invited reactions consistent with the potential threat represented by these infectious agents. However, with globalization, controlling epidemics depends as much on an effective global coordination of control methods as on preparedness of northern and southern national health care systems, at the core of which are health care workers. Our study was conducted in the National Hospital of Niamey, the main Nigerian hospital. Its objective was to evaluate the knowledge of health care professionals regarding flu pandemic and control of infection. We interviewed 178 nursing staff, doctors and paramedics on the basis of a survey. This study - the first to our knowledge to explore these issues in the African context-revealed that caregivers have a rather good mastery of theoretical knowledge. Nevertheless, beyond theoretical knowledge, miscellaneous factors compromise the effectiveness of the health care structure. Some of them seem to occupy a critical position, particularly the absence of shared references among sanitary authorities and health care professionals, and the weaknesses of global coordination of preventive activities and case management.

An integrated approach to distance learning with digital video in the French-speaking Virtual Medical University.

The aim of the French-speaking Virtual Medical University project (UMVF) is to share common resources and specific tools in order to improve medical training. Digital video on IP is an attractive tool for higher education but there are a number of obstacles to widespread implementation. This paper describes the UMVF approach to integrating digital video technologies and services in educational projects.

Evidence for qualitative abnormalities in high-density lipoproteins from myeloma patients: the presence of amyloid A protein could explain HDL modifications.

HDL apolipoproteins (apo) from normal subjects and patients with multiple myeloma were studied by isoelectric focusing (IEF) and by two-dimensional gel electrophoresis. Qualitative abnormalities were detected in myeloma HDL apolipoproteins. We observed two new bands not previously described in this disease. As determined by IEF and two-dimensional gel electrophoresis, the relative molecular weight of these two proteins was 12,600, with pI = 6.04 and 6.36, respectively. They correspond to two isoforms of serum amyloid A protein (SAA), as confirmed by western blot assay against specific antiserum to SAA. The high sensitivity of this assay revealed also other SAA isoforms. Our data are consistent with the hypothesis that major apolipoproteins of normal HDL, apo A-I and apo A-II, could be displaced by SAA isoproteins in myeloma HDL. This could lead structural changes in HDL.

Proliferative effect of high density lipoprotein (HDL) and HDL fractions (HDL1,2, HDL3) on virus transformed lymphoblastoid cells.

The growth-promoting activities of plasma lipoproteins (LDL, HDL, HDL1,2, HDL3) and total HDL apolipoproteins on a virus transformed lymphoblastoid cell line in vitro, has been compared. When maintained in lipoprotein-deficient serum-supplemented medium, these cells do not proliferate optimally. The addition of either HDL, HDL1,2 or HDL3 induced optimal cell proliferation as compared to the result observed in fetal calf serum-supplemented medium. The HDL1,2 subfraction was found to be more potent than the HDL3 subfraction in supporting cell growth. Total HDL apolipoproteins were able to support significant cell proliferation. In contrast, LDL did not promote cell growth. In serum-free conditions and in the presence of transferrin, only HDL and HDL subfractions induced cell proliferation. These results suggest that HDL and HDL subfractions could initiate B lymphoblastoid cell growth and that total HDL apolipoproteins could support a part of cell proliferation.

[Imported malaria at the Marseilles Hôpital-Nord, France: a prospective study on 352 cases between 2001 and 2003]. / Le paludisme d'importation à l'Hôpital-Nord de Marseille en 2001-2003: étude prospective de 352 cas.

OBJECTIVE: The authors had for aim to study epidemiological, clinical, and parasitological characteristics, as well as regimen received, of imported malaria cases hospitalised at the North University Hospital, in Marseilles, France. DESIGN: The patients presenting with imported malaria included in this study were hospitalised in the infectious and tropical diseases unit and in the pediatrics unit at the North University Hospital, from January 1, 2001 to December 31, 2003. Variables were prospectively collected and recorded. RESULTS: 352 patients including 240 adults and 112 children were included. Most of them (67% of the adults and 92% of the children) were contaminated during a trip to the Comoros Islands. Plasmodium falciparum was the most common species identified. 97.5% of adult and 98% of child patients back from Comoros did not take any chemoprophylaxis against malaria or took inadequate regimens. Halofantrin was the most commonly used drug for children to treat uncomplicated P. falciparum malaria. In adults, atovaquone-proguanil was used as a first line drug in the absence of vomiting, and a 3-day intravenous regimen of quinine-clindamycin in case of vomiting. CONCLUSION: The specificity of imported malaria in Marseilles is the high proportion of Comorian patients who go back home periodically to visit friends and relatives. A better education of the Comorian population in Marseilles, regarding malaria risks and prophylaxis, needs to be implemented.

[Chicken erythrocyte nuclei: composition and analysis of phospholipids]. / Les noyaux de globules rouges de poussin: composition et analyse des phospholipides

While many works analyse lipid composition of cellular nuclei, essentially of liver, few describe bird erythrocyte nuclei. For them very discordant results are reported due to very different methods of preparation. In the method we adopted a good reproducibility is controlled by electron microscopy, evaluation of specific enzymatic activities and by protein, RNA and DNA determinations. Total lipid content and phospholipid composition were determined showing, in agreement with other works, the predominance of phosphatidylcholine and phosphatidylethanolamine. On the contrary, the nuclear fraction is poor in sphingomyelin, which is essentially a plasma membrane phospholipid.

Involvement of tyrosine kinase activity in the low-density lipoprotein receptor expression in human lung adenocarcinoma cell line A549.

In common with other tumour cell lines but in contrast to normal cells, the human adenocarcinoma cell line A549 showed a biphasic regulation of the LDL receptor activity during growth both LDL binding and metabolism (sum of internalised and degraded LDL) increased during the log exponential growth phase and decreased when the cells approached confluence. This period of increasing LDL receptor activity coincided with a high resistance to cholesterol down-regulation which suggested a sterol-independent pathway of stimulation. Since A549 cells have an autocrine loop of growth factors, two of which have tyrosine kinase activity, the LDL receptor activity was tested in the presence of the tyrosine kinase inhibitor, genistein. When cells were incubated in the absence of cholesterol (LPDS medium), the inhibition that occurred was two-fold higher during the exponential growth phase than during the confluent phase. Moreover, the residual LDL binding and metabolism after genistein inhibition were completely resistant to down-regulation by cholesterol only during the growth phase. When cholesterol was present (FCS medium). inhibition was observed only during the growth phase. The inhibition of LDL receptor activity by genistein was found to be the result of a loss in the number of LDL binding sites, while the dissociation constant was not affected. This loss was accompanied by a disappearance of mRNA as shown by RNase mapping. By comparison, LDL receptor activity of normal cells (fibroblasts) was also affected by genistein during the exponential growth phase but was much more cholesterol-dependent. Taken together, these results suggest that the tyrosine kinase pathway is essential to up-regulate LDL receptor expression in highly dividing cells and particularly in tumour cells in which the sterol regulation is deficient.

Evidence for up-regulated low density lipoprotein receptor in human lung adenocarcinoma cell line A549.

Human lung adenocarcinoma cell line A549 was studied with respect to the metabolism of human low density lipoprotein (LDL) and 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase (HMGR) activity. After incubation in medium containing lipoprotein-deficient serum (LPDS) for 24 h, the A549 cell line expresses a single class of high affinity LDL binding sites (KD at 37 degrees C of 15.1 +/- 0.7 nM and capacity of 118 +/- 2.8 ng/mg cell protein) and an HMGR activity of 111.4 +/- 7 pmol/min/mg cell protein. After binding, the LDLs were internalized and degraded by a common saturable process. The HMGR activity was higher in A549 cells than in fibroblasts but LDL affinity and binding capacity were similar in both cell types. However, in the presence of lipoproteins, A549 cells showed a two-fold higher binding capacity than fibroblasts. When the cells were deprived of cholesterol, the amount of LDLR sites increased but the extent of stimulation was lower in A549 than in fibroblast cells (2.5-fold versus six-fold respectively). This increase was accompanied by a similar increase in the specific LDLR mRNA cellular levels (two-fold versus six-fold respectively). When cells were deprived of exogenous and endogenous cholesterol (biosynthesis blocked by compactin), the binding capacity and the LDLR mRNA levels were yet again increased in A549 cells but not in fibroblasts. Taken together these results suggest that the level of expression of the LDLR is up-regulated in A549 cells compared to fibroblasts.

Fatty acid composition of aortic lipids in male and female rabbits.

Aortic tissue of adult New-Zealand male and female white rabbits was studied. After thin-layer chromatography of cholesterol esters, triglycerides, free fatty acids, phosphatidylethanolamines and phosphatidylcholines, their fatty acid compositions are determined. Phosphatidylcholines and phosphatidylethanolamines contain important quantities of arachidonic acid. The level of linoleic acid in these phospholipids is higher in male animals than in female. Conversely the level of arachidonic acid is higher in females than in males.

Pharmacokinetics of Ro 03-8799 in mice bearing melanosarcoma: comparison with tumors without melanin.

The pharmacokinetics of Ro 03-8799 has been studied in melanic and non-melanic tumor bearing mice after iv administration of 150 mg/kg. The peak concentration in B16 melanosarcoma tumor reached 152 micrograms/g, that is 7.6-fold higher than the plasma concentration at the same time. This concentration is 3-times greater than that obtained in the tumor of mice bearing non melanic sarcoma (DB16) or Lewis lung carcinoma (3LL). The exposure of B16 tumor (AUC) is respectively 15-times and 11-times higher than the 3LL and the DB16 ones. These experimental data confirm that this 2-nitro-imidazol compound has an important affinity for melanin and suggest that it might be used as a radiosensitizer for the treatment of malignant melanoma.

Uptake and binding of teniposide (VM26) in Krebs II ascites cells.

With [3H] VM26 as marker, the uptake and binding of teniposide have been made in cells of Krebs II ascitic tumors. The intracellular accumulation of drug displayed a passive diffusion and a saturation kinetics with an apparent Michaelis-Menten constant of 37.54 10(-6) M and a flux of 13.4 nM/min/mg of protein. VM26 was rapidly taken and an equilibrium was established with the extracellular drug in about 30 min. The steady-state accumulation was diminished by Na+ and Ca2+ absence and VP16-213, whereas, K+ and Mg2+ have no effect. Energy dependence of the system was characterized by a Q10 of 1.75 +/- 0.2 and the uptake was reduced by ouabain and iodoacetamide, when 2-4-dinitrophenol and glucose absence were without appreciable change. The study of the efflux showed that about 87% of the uptaken drug was removed, the residual amount being probably irreversibly bound. The intracellular accumulation of the drug was associated with various cell organelles, however, only the nuclear fraction demonstrated a high affinity binding.

An in vitro study of hemicholinium-3 on phospholipid metabolism of Krebs II ascites cells.

With [Me-14C]choline as marker and after separation of choline and phosphocholine by ion-exchange column chromatography or thin layer chromatography on alumina, it is shown that 40 microM hemicholinium-3 (HC-3) inhibits the cytosolic choline-kinase of rat liver and Krebs cells. This inhibition is competitive (Km different, Vm similar) in the first case and mixed in the second (Km and Vm different). Despite this general inhibition of the phosphocholine formation, the synthesis of phosphatidylcholine (PC) by post-nuclear supernatants of rat liver and Krebs cells is different when tested with HC-3. It is unaffected in rat liver; however, HC-3 induces a PC deficiency in Krebs cells which is time-course dependent between 15 and 120 min and proportional to the drug concentrations in the interval 5-40 microM. Incorporation of AT-[gamma 32P] or [2-14C]ethanolamine into phospholipids shows that the sequential methylation pathway is not detectable in Krebs cells. These results are discussed in relation to those established concerning HC-3 action on phospholipid metabolism in other tissues.

Comparative study of the incorporation of ellipticine-esters into low density lipoprotein (LDL) and selective cell uptake of drug--LDL complex via the LDL receptor pathway in vitro.

Esters of elliptinium with stearic (ST-NME), palmitic (PAL-NME) or oleic (OL-NME) acids, a series of lipophilic derivatives of ellipticine, were synthetized, in order to evaluate their incorporation into Low Density Lipoprotein (LDL). Among the three derivatives, OL-NME shows the most potent incorporation (83 micrograms/mg protein LDL) compared to ST-NME (37 micrograms/mg protein LDL) and PAL-NME (58 micrograms/mg protein LDL). The size of OL-NME-LDL was determined by size distribution particles, showing their homogeneity compared to native LDL. When culture normal human fibroblasts were incubated with [125I]LDL incorporated drug, they bound to the LDL receptor with the same affinity as native LDL and were internalized and degraded intracellularly. The presence of excess native LDL inhibited the cellular uptake and degradation of [125I]drug-LDL. We have used [125I]acetyl-LDL as a probe for a binding site on macrophages that mediated the uptake and degradation of chemically altered or denatured LDL. Mouse peritoneal macrophages were shown to take up and degrade [125I]acetyl-LDL at rates that were greater than those for the uptake and degradation of native [125I]LDL and [125I]drug-LDL. The in vitro cytotoxic test on L1210 murine leukemic cells demonstrated that the complex was cytotoxic and was more effective than the free drug. This cytotoxic activity of the drug-LDL complex depends on the LDL high affinity receptor since the addition of native LDL reduces the killing power. In contrast, methylated LDL, which does not bind to the LDL receptor, has no effect on it. We conclude that it is possible to incorporate a large amount of cytotoxic drug into LDL without modifying their cellular metabolism via the high affinity LDL receptor pathway. It indicates also that the delivery of lipophilic drugs using LDL might provide distinct advantages over the use of synthetic carriers.

Distribution and tumor penetration properties of a radiosensitizer 2-[14C] misonidazole (Ro 07-0582), in mice and rats as studied by whole-body autoradiography.

The hypoxic cell radiosensitizer 2-[14C] misonidazole: 1-(2-nitro-1-imidazolyl)-3-methoxy-2-propanol (Ro 07-0582) MISO was administered to mice, control rats, and rats bearing chemically induced rhadbdomyosarcoma. The dose injected was 250 mg/kg and the delivered activity was 100 microCi/kg. Whole-body autoradiography was performed in all animals. We noted the highest uptake of radioactivity in the liver and the kidney. In the liver there was an accumulation of [14C] from 5 min to the 2 hour after treatment, followed by a decrease; this observation is probably related to the metabolic pathway of the drug. The radioactivity was also concentrated in the renal medulla (30 min after injection); this organ is the excretion route for most of the misonidazole or its metabolites. Fecal excretion is also important following biliary elimination. Radioactivity is present in the central nervous system in the first hours after dosage. [14C] Tumor activity was lowest 5 min after IP treatment. By contrast, 12 h after administration of labeled compound the highest activity was detected in this tissue.

Autoradiographic distribution of [14C]-labelled pimonidazole in rhabdomyosarcoma-bearing rats and pigmented mice.

The hypoxic cell radiosensitizer [2-14C] pimonidazole (2-nitro-alpha-(piperidinomethyl)-l-imidazole ethanol) was injected i.p. into pigmented mice and rats bearing transplanted rhabdomyosarcoma. The injected dose level was 200 mg/kg, and the delivered activity was 96 microCi/kg. Whole-body autoradiography was carried out on all animals. We noted an extensive whole-body distribution of radioactivity. At short intervals, the autoradiograms were characterized by an accumulation of radioactivity in the metabolic and excretory organs (liver, kidney, urinary tract, and intestinal content) as well as in lymphomyeloid tissues (thyroid gland, suprarenal gland, and hypophysis) and salivary glands. In pigmented mice, the uveal and biliary tracts were the highest labelled. The liver and particularly the renal medulla were identified as sites of retention of radioactivity. In the tumor the radioactivity was detected only in peripheral regions, with higher uptake in viable zones than in necrotic islets.

Pharmacokinetics of teniposide (VM 26) after IV administration in serum and malignant ascites of patients with ovarian carcinoma.

Nine patients with ovarian carcinoma and malignant ascites treated with IV teniposide chemotherapy (30 mg/m2/30 min) entered this study. Plasma and peritoneal fluid levels were measured by an HPLC method with electrochemical detection. Plasma decay kinetics followed a triexponential function. A high variability of drug diffusion in ascites was noticed. Peak concentrations in ascites ranged from 1.6% to 20.5% of serum peak concentration. The concentration in peritoneal fluid reached a maximum level 6 h after the infusion ended. Teniposide was less slowly eliminated from ascites than from serum. The exposure of the inflammatory peritoneal fluid to the drug expressed by area under the concentration-time curve (AUC) was also subject to significant interindividual variation, ranging from 223 to 2332 micrograms/ml X min. However, the peritoneal AUC was correlated with serum AUC and with the systemic clearance of the drug. A significant relationship between gamma glutamyltranspeptidase and both systemic clearance and either the serum or the peritoneal AUC was found, suggesting that liver plays a role in drug disposition.

Automated immunoturbidimetric assay of serum apolipoprotein A-II using the Cobas-Bio centrifugal analyser: influence of hyperlipoproteinemia.

A quantitative automated immunoturbidimetric procedure for the analysis of apolipoprotein A-II (Apo A-II) in human serum is described. Dilution of antibody with a 5% solution of PEG 6000 enhanced the quantification. The within- and between-assay coefficients of variation were less than 5%. Results correlated well with those obtained by classic electroimmunodiffusion and immunonephelometry. No extraction of samples with organic solvent was necessary, whatever the triglyceride concentration. Large lipoproteins such as VLDL and immunocomplexes did not affect the method, nor was there interference from icteric or hemolyzed serum or from serum with excessive hyperlipemia. Physiological values of Apo A-II were determined in a normal population. Concentrations were found to be age-dependent, and higher in women than in men. The procedure is very suitable for the rapid, precise, reproducible and inexpensive assay of Apo A-II.

A sensitive immunochemiluminescence assay for human serum amyloid A protein.

We describe an immunochemiluminescence assay for human plasma serum amyloid A protein (SAA) in which specific rabbit polyclonal antibodies against synthetic peptides are used. The detection of the antigen-antibody reaction at 425 nm is based on a brief emission of light by a luminophor component (signal) in response to chemical energy. The working range of the assay covers plasma SAA concentrations from 5 to 100 micrograms/L. The lower detection limit is 5 micrograms/L, the within- and between-assay CVs are less than 12%. Bilirubin, cholesterol and triglyceride in final concentrations of up to 220 mumol/L, 8.1 mmol/L and 2.68 mmol/L, respectively, do not interfere with the assay. Results were correlated with those obtained by the enzyme-linked immunosorbent assay using the same antibodies (r = 0.95; p less than 0.001; n = 50). This method is inexpensive, simple and easily automated.

Epidemiology and clinical features of vivax malaria imported to Europe: sentinel surveillance data from TropNetEurop.

BACKGROUND: Plasmodium vivax is the second most common species among malaria patients diagnosed in Europe, but epidemiological and clinical data on imported P. vivax malaria are limited. The TropNetEurop surveillance network has monitored the importation of vivax malaria into Europe since 1999. OBJECTIVES: To present epidemiological and clinical data on imported P. vivax malaria collected at European level. MATERIAL AND METHODS: Data of primary cases of P. vivax malaria reported between January 1999 and September 2003 were analysed, focusing on disease frequency, patient characteristics, place of infection, course of disease, treatment and differences between network-member countries. RESULTS: Within the surveillance period 4,801 cases of imported malaria were reported. 618 (12.9%) were attributed to P. vivax. European travellers and immigrants were the largest patient groups, but their proportion varied among the reporting countries. The main regions of infection in descending order were the Indian subcontinent, Indonesia, South America and Western and Eastern Africa, as a group accounting for more than 60% of the cases. Regular use of malaria chemoprophylaxis was reported by 118 patients. With 86 (inter-quartile range 41-158) versus 31 days (inter-quartile range 4-133) the median symptom onset was significantly delayed in patients with chemoprophylaxis (p < 0.0001). Common complaints were fever, headache, fatigue, and musculo-skeletal symptoms. All patients survived and severe clinical complications were rare. Hospitalization was provided for 60% and primaquine treatment administered to 83.8% of the patients, but frequencies varied strongly among reporting countries. CONCLUSIONS: TropNetEurop data can contribute to the harmonization of European treatment policies.

Hyperphosphatasemia related to three intestinal alkaline phosphatase isoforms: biochemical study.

An unexplained hyperphosphatasemia was noted in a healthy 47-year-old woman. The electrophoretic pattern on agarose gel with and without wheat germ lectin of the serum of this patient showed the presence of three isoforms which have been characterised as being of intestinal origin: their biochemical (neuraminidase, phenylalanine) and thermodenaturation properties are similar to those of intestinal tissue extract. The pI and pH optima of these isoforms agree with an intestinal origin. Our results suggest the existence of different allelozymes of intestinal alkaline phosphatase.