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Objective of the study: comparative evaluation of the bacteriotropic activity of Actoflor-S metabiotic and the exometabolic bifidobacteria complex.Materials and methods: in our work we used Actoflor-S dietary supplement as oral solution in 2 ml drop tubes (Solopharm). As a comparator drug, we used an exometabolite complex from the culture fluid of strain Bifidobacterium bifidum 1 obtained by method of ultrafiltration using separation apparatus with HOMM 15 kDa. We studied the stimulating effect of metabolite compositions on the acid forming activity and dynamics of the accumulation of lactobacilli Lactobacillus plantarum 8P-A3. Antagonistic activity against enterobacteria was determined in the test of inhibition of bioluminescence of the indicator strain Escherichia coli lum+ and quantified as an index of antibacterial activityResults and discussions. A comparative study of the effects of metabiotics on the acid forming activity of lactobacilli showed that both drugs have a pronounced stimulating effect on the probiotic strain L. plantarum. A comparative study of the effects of metabiotics on the model test strain of enterobacteria showed that whole preparations quickly and significantly (by more than 90%) inhibit the bioluminescence of E.coli lum+. Preparation dilutions 1:10 and 1:100 discovered significant differences in their activity. Given equal pH values (5.8 ± 0.1), Actoflor-S (dilution 1:10) inhibited the luminescence of E. coli lum + to a greater degree, exceeding almost 2 times the indicators of the metabolite bifidobacteria complex. It is revealing that Actoflor-S diluted 1:10 is not inferior to the whole preparation in terms of the level of effect on the test strain culture. What calls attention to itself is that large dilutions of UFLC of bifidobacteria after a short period of inhibition of luminescence of E. coli lum + have a stimulating effect. There is evidence that effect of inhibition of the luminescence of the control culture is dose-dependent.Conclusion. The results of a comparative examination of the bacterial action profile of the native exometabolites complex and Actoflor-S preparation confirm the presence of combination of the necessary inhibitory and stimulating activity against various agents of the microbiota. Creation of the metabiotics line based on Actoflor-S preparation with variability of biological properties and specialized for the management of various dysbiotic conditions show promise. An additional inclusion of native exometabolites of bifidobacteria and/or lactobacilli into the formula of artificial compositions will make it possible to expand the spectrum of the positive effect of probiotic preparations on the microorganism.

IntroductionPilot study associating hemodialysis-to-general-anesthesia time interval and post-operative complications in hemodialysis patients to better define a more optimal pre-anesthetic waiting period.MethodsPre-anesthetic and 48-hours post-anesthetic parameters (age, gender, body-mass-index, pre-operative ultrafiltrate, potassium, renal disease etiology, hemodialysis sessions per week, Acute Physiology and Chronic Health Evaluation-II score, Portsmouth-Physiologic and Operative Severity Score for the Enumeration of Mortality and Morbidity, American Society of Anesthesiologists physical status, Johns Hopkins Surgical Classification System Category, surgical urgency, intra-operative fluids, estimated blood loss, post-operative complications) were collected on chronic hemodialysis patients between 11/2009-12/2010. Continuous data were analyzed by Analysis of Variance or t-test. Bivariate data were analyzed by Fisher's Exact Test. Relative Risks/Confidence Intervals were calculated for statistically significant comparisons (p=0.05). Exclusion criteria were incomplete records, peritoneal dialysis, intra-operative hemodialysis, liver transplant, and cardiopulmonary bypass.ResultsPatients were grouped by dialysis to anesthesia time interval: Group 1 >24 hours, Group 2 7-23.9 hours, Group 3 < 7 hours. Among Surgical Category 3-5 patients, hypotension was more common in Group 3 than Group 1 (63.6% vs 9.2%, p

This study comprehensively investigated the influences of salinity, exposure concentration and time on the aggregate size, surface charge and dissolution of zinc oxide nanoparticles (ZnO–NPs; 20 nm) in seawater, and examined the interacting effect of salinity and waterborne exposure of ZnO–NPs on the marine diatom Thalassiosira pseudonana for 96 h. We found that aggregate sizes of ZnO–NPs significantly increased with increasing salinity, but generally decreased with increasing exposure concentration. Ion release decreased with increasing salinity, whereas the surface charge of the particles was not affected by salinity. The increased aggregate size and decreased ion release with increasing salinity, and consequently lower concentration of bioavailable zinc ions, resulted in decreased toxicity of ZnO–NPs at higher salinity in general in terms of growth inhibition (IC50) and chlorophyll fluorescence (EC50 – Ф Po and EC50 – Ф 2 ). However, IC50s and EC50s of ZnO–NPs were smaller than those of Zn 2+ (from ZnO–NPs ultrafiltrate and ZnCl 2 ), indicating that dissolved Zn 2+ can only partially explain the toxicity of ZnO–NPs. SEM images showed that ZnO–NPs attached on the diatom frustule surface, suggesting that the interaction between the nanoparticles and the cell surface may acerbate the toxicity of ZnO–NPs. Our results linked the physicochemical characteristics of ZnO–NPs in seawater with their toxicities to the marine diatom and highlighted the importance of salinity as an influential environmental factor governing the aggregation, dissolution and the toxicity of ZnO–NPs. [ABSTRACT FROM AUTHOR]

Effects of uremic ultrafiltrate on the regulation of the parathyroid cell cycle by calcitriol. Background. Calcitriol (CTR) is used in the treatment of hyperparathyroidism secondary to renal failure because it decreases parathyroid hormone (PTH) synthesis and parathyroid cell proliferation. Previous studies in tissues other than parathyroids have demonstrated that uremic factors affect the action of CTR on the target cells. We questioned whether the uremic milieu interferes with the inhibition of parathyroid cell proliferation by CTR. Methods. Studies were performed in vitro using freshly excised normal dog parathyroid tissue incubated for 24 hours with and without CTR and in the presence of either total uremic ultrafiltrate (UUF) from uremic patients or high-pressure liquid chromatography (HPLC)-derived fractions (hydrophilic compounds eluting early and hydrophobic compounds eluting late) of this UUF (F1 to F4). Parathyroid cell proliferation was assessed by flow cytometry. Results. The addition of CTR 10-8 and 10-7 mol/L to parathyroid tissue produced an inhibition of the proliferation that was prevented in the presence of UUF. In a medium containing CTR 10-8 mol/L, the addition of F1, F2 and F3, but not F4, prevented the CTR-induced inhibition of parathyroid cell proliferation. With CTR 10-7 mol/L, the inhibition of proliferation was observed even in the presence of F1, F2 and also F4, but was prevented by F3. Uric acid (7 mg/dL), indoxyl sulfate (5 mg/dL) and p-cresol (1.4 mg/dL), which coeluted with F1, F2 and F4, respectively, did not interfere with the inhibitory action of CTR 10-7 mol/L; however, the addition of phenol (0.14 mg/dL), which coeluted with F3, prevented the CTR-induced inhibition of parathyroid cell proliferation. Conclusions. The presence of uremic toxins prevents the inhibition of parathyroid cell proliferation induced by calcitriol. [ABSTRACT FROM AUTHOR]

Hemofiltration reduces the serum priming activity on neutrophil chemiluminescence in septic patients. Background. Priming of the polymorphonuclear neutrophil (PMN) response has been implicated in the activation of oxidative burst and tissue injury in patients with septic shock and acute renal failure (ARF). This study evaluated whether hemofiltration (HF) removes substances able to enhance the oxidative burst of PMNs. Methods. Chemiluminescence (CL) priming activity induced by sera and ultrafiltrates of seven patients with septic shock, multiorgan dysfunction syndrome, and ARF (ARF/HF group) and of 10 uremic stable patients (Control/HF group) was evaluated on normal human PMNs stimulated with bacterial formyl-methionyl-leucyl-phenylalanine (FMLP). Patients submitted to HF were studied by determining blood and ultrafiltrate interleukin-8 (IL-8), platelet-activating factor (PAF), and CL priming activity at the beginning (T0), and after four hours (T4) of treatment. Results. Preincubation of normal human PMNs with sera and ultrafiltrates from septic patients induced a potent priming of CL activity in subsequent FMLP stimulation. In the ARF/HF group, the prefilter blood concentrations of IL-8 and CL PMN-priming activity significantly decreased during the four hours of HF treatment, with a loss of IL-8 in the ultrafiltrate of 6930 (median, range 4292 to 9282) ng per four hours. PAF detected in the ultrafiltrate and associated with the membrane (7.3 ng, range 1.45 to 9.89) was minimal. In the ARF/HF group, a significantly positive correlation between CL PMN-priming activity and IL-8 concentrations was observed. The CL priming activity in blood and ultrafiltrates was reduced to 55 and 46% by preabsorption with monoclonal antibody (mAb) anti-IL-8. In contrast, the PAF receptor antagonist WEB 2170 did not affect CL priming activity. In the control/HF group, the CL PMN-priming activity was significantly lower than in the ARF/HF group and was... [ABSTRACT FROM AUTHOR]

Adsorption in hemodialysis. The use of sorbents in different blood purification techniques is reviewed. The sorbents used in these therapies are divided into two groups: ( 1 ) Adsorption occurs fundamentally because of the hydrophobic properties of the sorbents. In this group, the sorbents used in different dialysis techniques are charcoal and nonionic macroporous resins. ( 2 ) Adsorption occurs by chemical affinity, such as ion exchange resins and chemisorbents. Sorbents were initially used in hemoperfusion, which caused many adverse events; later, with the use of coated charcoal, these undesired effects decreased or disappeared, but the adsorptive properties, water control, and acid-base balance still created problems. For these reasons, the use of sorbents in the treatment of chronic renal failure was almost totally discontinued. Little by little, interest in these substances has reappeared, and at present, they have been used in combination with other blood purification techniques such as hemodialysis, hemofiltration, peritoneal dialysis, and finally, hemodiafiltration. Within the various hemodiafiltration techniques, paired filtration dialysis-charcoal is being used to regenerate the ultrafiltrate, which is used as the replacement fluid. Charcoal regenerates the ultrafiltrate and transforms it into a physiological solution with a normal electrolyte composition, calcium, bicarbonate, and glucose, having eliminated the majority of both middle and large molecule uremic toxins. If regeneration is done properly, this replacement fluid is bacteria and endotoxin free. Studies currently are underway on the adsorption of different inflammatory substances in the ultrafiltrate, which could lead to improvement in the biocompatibility of the system. [ABSTRACT FROM AUTHOR]

Introduction: Pilot study associating hemodialysis-to-general-anesthesia time interval and post-operative complications in hemodialysis patients to better define a more optimal pre-anesthetic waiting period., Methods: Pre-anesthetic and 48-hours post-anesthetic parameters (age, gender, body-mass-index, pre-operative ultrafiltrate, potassium, renal disease etiology, hemodialysis sessions per week, Acute Physiology and Chronic Health Evaluation-II score, Portsmouth-Physiologic and Operative Severity Score for the Enumeration of Mortality and Morbidity, American Society of Anesthesiologists physical status, Johns Hopkins Surgical Classification System Category, surgical urgency, intra-operative fluids, estimated blood loss, post-operative complications) were collected on chronic hemodialysis patients between 11/2009-12/2010. Continuous data were analyzed by Analysis of Variance or t-test. Bivariate data were analyzed by Fisher's Exact Test. Relative Risks/Confidence Intervals were calculated for statistically significant comparisons (p=0.05). Exclusion criteria were incomplete records, peritoneal dialysis, intra-operative hemodialysis, liver transplant, and cardiopulmonary bypass., Results: Patients were grouped by dialysis to anesthesia time interval: Group 1 >24 hours, Group 2 7-23.9 hours, Group 3 < 7 hours. Among Surgical Category 3-5 patients, hypotension was more common in Group 3 than Group 1 (63.6% vs 9.2%, p<0.0001, relative risk=6.9, confidence interval=3.0-15.7) or Group 2 (63.6% vs 17.3%, p=0.0002, relative risk=3.7, confidence interval=1.9-7.2). Other complications rates were not statistically significant. Disease and surgical severity scores, preoperative ultrafiltrate, and intra-operative fluids were not different., Conclusions: Post-anesthetic hypotension within 48 hours was more common in those with < 7 hours interval between dialysis and anesthesia. Therefore, if surgical urgency permits, a delay of ≥7 hours may limit postoperative hypotension. More precise associations should be obtained through a prospective study.