Background/Aim: Substances in the middle molecular weight range have been shown to play a significant pathogenetic role in as diverse disorders as end-stage renal disease and multiple organ failure. To overcome the limitations in the amount removed by hemofilters, new sorbents with a high biocompatibility are actively being developed. Furthermore, biocompatible sorbents by their nonspecific adsorptive behavior could have great impact on detoxification treatment in exogenous intoxications. We performed an in vitro evaluation of a newly developed highly biocompatible sorbent cartridge (Betasorb^®), examining its adsorptive capacity concerning therapeutic drugs. Methods: Uremic blood spiked with a range of therapeutic drugs was recirculated for 2 h in an in vitro hemoperfusion circuit containing a Betasorb device for hemoperfusion. The drug concentrations before and after the passage of the cartridge were measured, and the total amount removed was calculated. Results: The sorbent showed effective removal of glycopeptide antibiotics, digoxin, theophylline, phenobarbital, phenytoin, carbamazepine, and valproic acid. Moderate removal could be demonstrated for tacrolimus and cyclosporine A; aminoglycosides were removed to a small extent only. Conclusions: Betasorb hemoperfusion shows a potent adsorptive capacity concerning therapeutic drugs (except aminoglycosides) and could be of major value in the treatment of intoxications. On the other hand, drug monitoring and possible adjustments are necessary during Betasorb hemoperfusion to maintain the therapeutic ranges of the drugs in blood.

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Very few innovations have characterized the different components of the hemodialyzers in the past 20 years. Most improvements have concerned membrane biocompatibility. In this article, we focus our attention on the most recent advances in hemodialyzer components from the macro design of the unit to the nanostructure of the membrane. For this purpose, we took as an example the FX class of hemodialyzers (FMC, Bad Homburg, Germany). The studied devices were chosen as an example representing some of the most recent hemodialyzers and are well suited to describe technical innovations occurring in the field of dialyzer technology. In vitro and in vivo studies were performed to characterize hemodynamic parameters of three models (1.4-1, 8, and 2.2 m2) and to determine membrane permeability, sieving coefficients, and solute clearances. The units were characterized by a relatively high resistance of the blood and dialysate compartments, leading to an increased internal filtration if compared with similar hemodialyzers of other series. Nevertheless, the flow distribution in both compartments was homogeneous and well balanced. This effect was obtained by the improved blood and dialysate ports design, the increased packing density of the fibers and a reduction of the inner diameter of the fibers from 200 to 180 microm. At the same time, the sieving coefficients for middle-large solutes such as beta2 microglobulin and insulin were higher than those observed in standard high flux dialysers. The same effect was noted for the clearance values of these solutes. This was observed in the absence of significant albumin leakage. These results were obtained thanks to a new nano-controlled spinning technology applied to the fiber. The innermost layer of the membrane is in fact characterized by a homogeneous porosity, with increased number of pores of large dimension but a sharp cutoff of the membrane excluding albumin losses. In conclusion, new technologies and new diagnostic tools today allow for improvement in hemodialyzer design from its macro-components to its nano-structure. The application of nanotechnology to hemodialysis will probably contribute to further developments in hemodialyzer manufacturing.

Age and close living conditions are known to be risk factors for the acquisition of Helicobacter pylori (HP) infection. It is unknown whether institutionalization of asymptomatic, elderly subjects is an additional risk factor and whether gastric function and nutritional status are affected by the HP infection. The study sample comprised 102 subjects over 65 years of age: 52 living in a nursing home and 50 at home. No subject had symptoms or previous pathology related to the upper digestive tract. In all subjects, serum levels of specific anti-HP antibodies were determined. Gastric function was evaluated by levels of pepsinogen A (PGA), pepsinogen C (PGC) and gastrin. The nutritional status of the subject was evaluated by measuring: albumin, haemoglobin, iron, ferritin, transferrin, vitamin B12, and folic acid in blood, and body mass index and mid-arm muscle area. The prevalence of anti-HP antibodies was 86.5% in institutionalized subjects (men: 100%; women:76.6%, p <0.05) and 82.0% in subjects living at home (men:86.3%; women:76.3%). No differences between the two groups were observed in levels of serum anti-HP antibodies and PGC was identified. In neither group were differences observed between serum positive (HP + ve) and negative (HP - ve) subjects with respect to the biohumoral and anthropometric indices of nutritional status. We conclude: (1) the seroprevalence of the HP infection was high (82-86%) in asymptomatic elderly patients living either at home or in an institution; (2) the presence of specific IgG anti-HP antibodies in asymptomatic elderly individuals, at home or in a nursing home, was not associated with changes in PGA levels in institutionalized subjects; (3) nutritional indices were not influenced by the presence of anti-HP antibodies.

In the elderly, triple therapy with omeprazole+metronidazole+clarithromycin for 1 week is well tolerated and highly effective; anti-H. pylori antibody and PGC serum levels decrease soon after anti-H. pylori therapy only in patients cured of H. pylori infection.