[Not Available]. / Influence de la complexation sur le transfert des cations en osmose inverse.

The influence of complexation by different ligands on the transfer of metallic cations in reverse osmosis has been studied by using membranes composed of aromatic polyamides. In spite of the large volume increase of the diffusing solute, the addition of a complexant can significantly improve the transfer of metallic cations through a reverse osmosis membrane. The most important factor in the improvement of the transfer is the solubility in the membrane of the complexes created. This solubility is linked to the possibility of creating hydrogen bonds between the membrane and the complex. Moreover, the addition of substances which strongly solvate both the membrane and the solute leads to an improvement of transfer which increases considerably with the increasing pressure. These results suggest the possibility of separating metal cations by specific complexation.

[Not Available]. / Mise au point d'un programme de calcul des diagrammes de repartition des complexes a force ionique variable.

A computer program DISCOMP FORTRAN permits the drawing of distribution diagrams for different complexes as a function of the concentration of ligand, taking into account the continuous variation of ionic strength. The scope of the program has been limited to cases in which one metal and one ligand are involved, without protonated or hydrolysed species, but an attempt has been made to establish the program so that it can be adapted to each practical case. The first part of the study deals with the theory and general equations corresponding to the formation of complexes, and in the second the program is developed step by step. Because the changes in ionic strength are not negligible, stress has been laid upon their importance. It should be noted that the empirical coefficient C of the Debye-Hückel equation has to be determined to obtain better precision.

Selective demineralization of water by nanofiltration application to the defluorination of brackish water.

Nanofiltration is generally used to separate monovalent ions from divalent ions, but it is also possible to separate ions of the same valency by careful application of the transfer mechanisms involved. Analysis of the retention of halide salts reveals that small ions like fluoride are the best retained, and that this is even more marked under reduced pressure when selectivity is greatest. The selectivity desalination of fluorinated brackish water is hence feasible and drinking water can be produced directly at much lower cost than using reverse osmosis by optimizing the pressure for the type of water treated.

Oxidising and disinfecting by hydrogen peroxide produced in a two-electrode cell.

Hydrogen peroxide was produced by direct current electrolysis using two electrodes only, a carbon felt cathode and a dimensional stabilised anode (titanium coated with RuO2), without adding any chemical. The required oxygen was supplied by water oxidation and by transfer from the atmosphere. The intensity should be maintained under a maximum value to avoid peroxide reduction. High peroxide production rate and concentration were then reached. Electroperoxidation partially removed dissolved organic carbon (DOC) contained in solutions of phenol, salicylic acid, benzoic acid and humic acids. The DOC removal in effluent of municipal sewage plant corresponded to a breakage of the double bonds. Real effluents were significantly disinfected owing to the direct effect of electric current and the indirect effect of peroxide. Moreover, a remnant effect was ensured.

Writing disorders and their relationship to reading-writing methods: a longitudinal study.

This study was designed to investigate some writing disorders shown by children who have been taught by different methods of reading and writing. Methods differ in that some emphasize the processes of decoding bottom-up (e.g., syllabic and phonic method) while others stress top-down processes, that is, they put greater emphasis on meaning (e.g., global-natural method). A longitudinal study using a sample of 260 school children was performed. The children were of both sexes from public and private schools and from different socioeconomic backgrounds. It was found that the pupils who learn by a global-natural method make errors that relate more to reproductive aspects of information. In contrast, the pupils who learned by the phonic and syllabic methods made more errors of meaning.

[Dermatomyositis associated with lethal pulmonary fibrosis and cutaneous necrosis (author's transl)]. / Dermatomyosite, fibrose pulmonaire léthale, nécroses cutanées (A propos d'un cas).

This clinical report concerns a 57 year old woman with dermatomyositis and cardiac involvement. After an apparent clinical and biological improve of the muscular and myocardic symptoms, a pulmonary involvement was reported. There was a persistent high rate of lacticodeshydrogenase serum activity. Then, cutaneous ulcerations and necrosis appeared on the extremities of limbs. Dermatomyositis associated with cutaneous necrosis and pulmonary fibrosis has a very severe prognosis.

[Methicilline-sensitive and methicilline-resistant Staphylococcus aureus related morbidity in chronic wounds: a prospective study]. / Etude prospective comparative de la morbidité des Staphylococcus aureus métisensibles et métirésistants dans les plaies chroniques.

OBJECTIVE: Staphylococcus aureus is the most common bacteria responsible for cutaneous infections. Its capacity to adapt has led to the selection of methicilline-resistant strains (MRSA). These strains create specific problems in their management in dermatology (mode of contamination, treatment, added costs, increased nosocomial risks). The objective of our study was to search for morbidity of MRSA in chronic cutaneous wounds in hospital settings and assess the need of systemic antibiotic therapy. PATIENTS AND METHODS: We have conducted a one-year prospective study. All the patients hospitalized in the department with leg ulcers or foot wounds were included. Following local sampling for bacteriological examination, three groups were constituted: methicilline-sensitive patients with staphylococcus aureus (MSSA), methicilline-resistant staphylococcus aureus patients and patients in whom these bacteria were absent. Only the first two groups were compared after studying the past history, clinical description of the wound at the start of the study, results of the infectious bacteriology and of the clinical and bacteriological evolution of the wounds. RESULTS: The two groups studied were similar in number, past history, clinical aspect and therapeutic management. Only malnutrition was more frequent in patients exhibiting MRSA. There was no difference with the evolution of the wounds. CONCLUSION: Our study did not reveal any difference in the morbidity of staphylococcus aureus in the cutaneous wounds whether methicilline sensitive or resistant. Systematic antibiotherapy is not justified in the absence of signs of infection.

[The fluorosis problem in Senegal: data evaluation and presentation of a new method for defluoridating the water supply]. / Sur le problème de la fluorose au Sénégal: bilan des connaissances et présentation d'une nouvelle méthode de défluoruration des eaux de boisson.

Fluoride intoxication is a serious public health problem in Senegal. The concentration of fluoride ions in underground water in Senegal is higher than the acceptable standard (0.7 mg/l at 25 degrees C) varying between 5 and 15 mg/l according to the season. The hydrological pattern of fluoride ions in Senegalese water is presented. The high levels of fluoride ions are due to the presence of phosphate ores. The health problems associated with the ingestion of toxic doses (about 4 mg/l) are discussed. Epidemiological investigation shows that the intoxication in Senegal is serious. In addition to fluoride in drinking water, high levels are also found in food, particularly tea and vegetables. Nanofiltration is a low cost membrane-based process which can be used to eliminate fluoride from drinking waters. Also known as low pressure reverse osmosis, this process is selective for small molecules and ions. It can thus sterilize and partially demineralize water. Furthermore, it can require only small amounts of energy, such that it can be run from photoelectric cells.

Improved oral hygiene and Candida species colonization level in geriatric patients.

OBJECTIVES: This work consists in improving oral hygiene (OH) for elderly dependent people in long-term hospital care, in order to decrease the degree of colonization and the associated risk of developing oral candidiasis. As this population frequently suffers from such colonization and because it is difficult to install and practice OH care, a study protocol was designed at the request of geriatricians. The objective of the present study was to set up a programme of OH, applied by the care staff, and to monitor oral colonization of by Candida spp. BASIC RESEARCH DESIGN: We compared the levels of hygiene and Candida spp. colonization for a group of 110 long-term patients in geriatric departments at T1, when clinical data were collected and oral mycological samples taken before the OH protocol was applied, and at T2, during the postprotocol phase after 3 months of application, when the clinical data and sample collection were repeated. RESULTS: During these 3 months 11 patients died. These patients were excluded from the results, which are presented for matched series of the 99 patients still present at T2. Statistical analysis comparing the clinical and biological parameters at T1 and T2 established that there had been an improvement in OH: the 'adequate' level was reached for 72.4% of patients at T2 compared with 41.8% at T1 (P < 0.001) and the 'very inadequate' level was observed for 9.2% at T2 compared with 27.9% at T1 (P < 0.01). A reduction was observed in the number of patients showing the highest degree of C. albicans and C. glabrata colonization (> 50 colony forming units) from 41.9% at T1 to 24.9% at T2 (P < 0.05) and from 56.4% at T1 to 13.0% at T2 (P < 0.05) respectively. The number of patients with candidiasis fell significantly from 43.2% at T1 to 10.2% at T2. CONCLUSIONS: The OH protocol led to an overall decrease in Candida spp. colonization, a significant reduction in the number of candidiasis and an improvement in the level of oral and denture hygiene but vigilance is still necessary concerning OH care and the initial training of staff in specific care of the mouth.

[Effects of the PETN-piridoxylate combination in the long-term treatment of cardiac failure in the aged patient]. / Effets de l'association PETN-piridoxilate dans le traitement au long cours de l'insuffisance cardiaque du sujet âgé.

Vasodilator treatment with long-activity nitrate derivatives intensifies the effects of treatment with digitalis and diuretics in left ventricular insufficiency. The object of this study was to evaluate, in an open comparative trial, the clinical effects of a prolonged adjunctive treatment with Mycoril, which is composed of a sustained-release nitrate derivative (pentaerythrityl tetranitrate: PETN) and an antianoxic agent (piridoxilate). The study was conducted in 90 patients with cardiac insufficiency who were treated and followed-up for at least one year. Study patients were divided into two groups matched for age, sex and etiology. The control group (42 patients) received digitalis and diuretics; the treatment group (48 patients) was given digitalis, diuretics and Mycoril in a daily dose of 4 to 6 capsules. The results show a significant improvement of symptoms in patients with ischemic cardiac insufficiency treated with Mycoril (83%) compared with the control group (52%) (p less than 0,03). Diuretics were needed in lower doses or withdrawn in a significantly higher number of patients in the Mycoril group (67%) than in the control group (38%) (p less than 0,01). This study provides clinical confirmation of the value of adjunctive treatment with a product such as Mycoril in patients under digitalis and diuretic therapy.

Plasma DNA as cell death marker in elderly patients.

Plasma DNA increases where cell death occurs in vivo. To investigate its significance in elderly patients, plasma DNA was assayed in 79 institutionalized patients over 68 years of age. The patients were divided into two groups: group I comprises 39 patients suffering from various acute or chronic illnesses; group II comprises 40 patients without chronic disease, and free of any clinical or biological symptoms of any infectious or inflammatory process. Plasma DNA was higher in group I than in group II (p < 0.0001) and in group II than in a control group of middle-aged subjects (p < 0.05). In group I, increase in plasma DNA concentration was found in various pathological situations associated with cell death phenomena, including infections, cancers with metastasis, hepatitis, irreversible cardiac failure, severe respiratory insufficiency and thrombophlebitis. Plasma DNA concentrations were not correlated with erythrocyte sedimentation rate, fibrinogen concentration, hemoglobin concentration or leukocyte count. In group I, as well as in the overall population, survival after 1 month was significantly reduced in patients with increased concentrations of plasma DNA. In conclusion, plasma DNA as a marker of cell death phenomena occurring in vivo, could be helpful for follow-up and management of elderly patients.