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Icodextrin is a glucose polymer derived from starch that is used as an osmotic agent in peritoneal dialysis. Its high molecular weight limits blood absorption and is useful for long dwell since there is few osmotic gradient dispersal. Its benefits are numerous: ltrafiltration optimization and better salt and water control especially in anuric patients with a high peritoneal permeability and also in case of infectious peritonitis, glucose sparing with less metabolic complications and a better preservation of peritoneal membrane, better biocompatibility. However it should not be forgotten that icodextrin has also side effects that must be known: allergies, cases of aseptic peritonitis, overintense water and salt depletion, lymphatic absorption of icodextrin and its metabolites (including maltose) with a risk of false capillary glucose rate estimation and a moderate increase in plasma osmolality. That is why it is not recommended now to use more than one daily icodextrin dwell. Nevertheless, several dialysis units use icodextrin in more than one daily dwell, especially in patients with an important ultrafiltration loss or in those in whom glucose sparing is essential. It seems to profit them with no more side effects. A large multicenter trial is in progress to test the efficacy and safety of icodextrin dwell twice a day in elder incident patients in peritoneal dialysis (DIDo). Moreover, icodextrin is also used combined with glucose in a long dwell (bimodal ultrafiltration) with encouraging results in terms of ultrafiltration and glucose sparing.

Conventional peritoneal dialysis solutions are mostly bioincompatible in relationship with a low pH, a high glucose and glucose degradation products (GDP) concentrations inducing anatomical and functional peritoneal membrane alterations. Use of icodextrin solution instead of glucose hypertonic solution preserves peritoneal membrane minimizing glucose exposure and its peritoneal absorption. Physiological fluids with a neutral pH and less GDP seem to have a positive effect on residual renal function which declines more slowly when they are early prescribed, before highly damaged and sclerotic kidneys. Preliminary data show that patients and technique survivals are better when physiological solutions are used either for diabetic and non diabetic patients. However, these new solutions do not improve peritonitis rates except for bicarbonate solutions but this fact must still be confirmed by other studies. In spite of a higher cost, physiological solutions must be proposed mainly for patients with a low comorbidity index and a high life expectancy.

Mouldy surfaces are encountered in up to 20 % of dwellings. Because this indoor air contamination is so widespread, respiratory physicians should be aware of its effects on health and especially of its impact on respiratory diseases.The air contaminants within mouldy dwellings are very diverse. Therefore, a given heath effect cannot be attributed specifically to an individual contaminant. In the field of respiratory diseases, excluding asthma and allergy, long-term exposure to indoor moulds has been recognized as a risk factor for both ENT and bronchial symptoms. Hydrophilic moulds seem to have a larger health impact than other mould species. Among respiratory diseases, inhalation fever and, to a lesser extent, childhood respiratory infections are linked to exposure to moulds. In contrast, the relationship between exposure to indoor moulds and diseases such as sinusitis, mucous irritation syndrome, recurrent respiratory infections in adults, COPD and pulmonary haemorrhage has not been clearly established.There are still many scientific uncertainties in this field. However, the authorities are becoming more active in dealing with unhealthy buildings and encouraging research.The health impact of mouldy dwellings represents a major public health issue. It needs incentives from institutions and financial support as well as the involvement of many specialists.

Cardiovascular disease remains the leading cause of death in ESRD patients related to long-standing hypertension. Early studies had recognized the favourable effect of PD in controlling hypertension but it was soon realized that such benefit was not sustained. A U shaped trend of hypertension in patients on PD has been recently demonstrated as a result of a steadily increased blood pressure partly attributed to fluid retention resulting from lower sodium removal with time. Effort in selecting the best strategy of ultrafiltration for a single patient along with a careful and frequent monitoring of combined 24 hours sodium elimination coupled with dietician counseling can improve significantly fluid an sodium balance which in turn will result in much better blood pressure control. The contribution of progress in biocompatibility of PD fluid that better preserve renal function and the implementation of the first glucose polymer Icodextrin were key interventions in that aim. Further studies should be conducted to assess the power of innovative PD solutions--Low Sodium PDF and/or Bimodal Ultrafiltration--in enhancing fluid and sodium removal during CAPD/APD programmes.

The ability of different hydrolytic bacteria from the human colon to grow on various algal polymers (carrageenans, Palmaria palmata xylan, ulvan, desulphated ulvan and laminaran) was investigated and the interactions between Bacteroides thetaiotaomicron and H2-utilizing microorganisms (one methanogenic archaea and an acetogenic bacterium) were studied during laminaran degradation. None of the algal polysaccharides supported the growth of any of the hydrolytic species tested, except for laminaran, which allowed substantial growth of B thetaiotaomicron. This suggested that bacterial consortia were involved in algal polymer breakdown rather than one specific bacterial species. The presence of H2-utilizing microorganisms did not increase the extent of laminaran degradation by B thetaiotaomicron. Whereas the decrease in formate and H2 concentrations attested to their utilization by both hydrogenotrophic microorganisms, the large increase in acetate production observed in the coculture with acetogenic bacteria was mainly due to acetogenic fermentation of sugars released during laminaran hydrolysis.

The desertomycin action upon Saccharomyces uvarum wall synthesis has been studied. Spheroblast regeneration was carried out in a liquid medium containing labeled glucose to monitor the synthesis of different wall components. In the presence of desertomycin, wall synthesis was affected; this was expressed as a net reduction of insoluble alkali constituents content, more precisely the insoluble acido-alkali fraction that, in yeasts, is constituted by chains of beta(1,3)-glucans linked among themselves by beta(1,6) bonds. Mannan formation was not inhibited such polymers that cannot be fixed to the glucan matrix of the wall were liberated in the regeneration medium. Because of desertomycin action, the decrease in insoluble alkali content revealed an interference with the enzymatic systems catalyzing glucan synthesis. In vitro, however, this antifungal had little effect upon glucan synthetase activity: doses 5 times superior to the subinhibiting level used in vivo caused only 30% inhibition. This result can be explained by an indirect action of desertomycin. Parietal disorders were the result of membrane structure disturbance, notably the phospholipids and localized enzymatic systems. This antifungal presents an analogical structure with macrolides with recognized membrane action.

Like other fungi, Botrytis cinera produces an exocellular beta-(1 leads to 3)-glucanase. This constitutive enzyme is produced only when Botrytis is cultivated in a glucose depleted medium. The enzyme is precipitated by ammonium sulfate from 20 to 80% saturation. Maximum activity is at pH between 5 and 6 and temperature between 40 and 50 degrees C; stability is good up to 30 degrees C. This enzyme cannot be applied to the treatment of wines containing Botrytis glucan.

The effect of beta-1,3 glucan and cell walls of S. cerevisiae on one hand and of peptidoglycans from strain LDC 15 and C. renale and cell walls of C. Hofmannii on the other hand has been investigated in the experimental leprosy infection in mice. beta-1,3 glucan, by enhancing the function of the reticulo-endothelial system, is the most active inhibitor of the multiplication of Hansen's bacilli. Peptidoglycan of strain LDC 15 is less active and seems non specific.

The immunopotentiating activity and mechanisms of PSAT and scleroglucan, two beta 1-3, beta 1-6 glucan, were investigated in mice: these polysaccharides increase the chemiluminescence of peritoneal phagocytes and the serum C3 level. Augmentation of DNA synthesis of spleen cells was induced in vivo by injecting PSAT or scleroglucan. An additional proliferative effect of these polysaccharides was observed when spleen cells were incubated with mitogens. Moreover, PSAT enhances the number of Thy1 lymphocytes and increases the ratio of lymphocytes L3T4/Lyt2 in mice infected with Toxoplasma gondii. No significant changes in immunoglobulin levels were found. These data indicate that PSAT and scleroglucan favorably affect the non-specific host defense and cellular immune response in mice.

A chemical method for lipid extraction has been applied to Candida albicans blastospores previously to their examination by transmission electron microscopy. The results led to the concept of a superficial location of lipids bounded to the peptidopolysaccharidic matrix of the cell wall. This lipid extraction also allowed us to describe cell wall microfibrillar structures. Two types of microfibrills have been particularly identified: microfibrils of approximately 50 A in diameter, involved in a network of the cell wall intermediate layers and supposed to correspond to beta 1-3 glucans; fibrillar structures of 120 A in diameter, similar to chitin microfibrils, observed in the bud scar septum.

Several polysaccharides have been isolated from the cell walls of Phytophthora parasitica, a phytopathogenic fungus of carnation. The crude polysaccharides were fractionated by successive chromatographies on DEAE-cellulose, Sephadex G-25, concanavalin-A-Sepharose and Sephadex G-200 columns. The neutral polysaccharides consist of a mixture of beta(1----3, 1----6)-D-glucans whose relative molecular masses varied from 9000 to about 200 000. All these polysaccharides have a main chain of beta(1----3)-linked D-glucose residues. They differ by the presence of 1----6 branched chains consisting of D-glucose and D-Glc-(1----3)-D-Glc, for the lowest molecular mass polysaccharides or D-Glc-(1----3)-D-Glc-(1---3)-D-Glc for the highest molecular mass polysaccharides.

Immunomodulators, whether natural (polysaccharides) or industrial (non-hemolytic detergents) proved active by themselves, in preventive or curative schemes of experimental leprosy and malaria. However, their activity was most often increased, through joint administration with chemotherapeutic agents.