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PubMed2001

Efficient control of activated sludge filamentous bulking by means of a multi-component additive.

A multi-component additive formulated for a more efficient control of activated sludge filamentous bulking was evaluated at a full-scale treatment plant experiencing a severe filamentous bulking. It was found that, besides offering an immediate improvement of sludge settling, the multi-component additive was able to eliminate the filamentous bacteria causing the bulking. Hence, contrarily to ordinary additives, this novel additive yielded immediate as well as long-term improvement of sludge sedimentation upon a few additions.

Food Industry↗
PubMedDate not supplied

Effect of alum addition on the performance of submerged membranes for wastewater treatment.

The effect of aluminum sulfate (alum) addition on membrane performance was investigated, with a particular focus on membrane fouling. During initial operation, alum was added and the performance monitored. After terminating alum addition, the transmembrane pressure (TMP), which is indicative of membrane resistance to flow or fouling, increased. Accompanying the increase in TMP was an increase in the organic nonsettleable fraction (colloidal + dissolved) content of the mixed liquor and deterioration of permeate quality and floc strength. Permeate polysaccharide concentrations increased significantly, suggesting a preferential binding of solution polysaccharides by alum. Upon reinitiating alum addition, the TMP only partially recovered, indicating some irreversible fouling, while mixed liquor nonsettleable organic material, permeate quality, and floc strength returned to initial levels. These results suggest that direct alum addition to membrane bioreactors can improve membrane performance by reducing the organic fouling material and improving floc structure and strength. It appears that bulk liquid polysaccharides may contribute to irreversible membrane fouling, and this fraction can be efficiently controlled through the alum addition.

Alum Compounds↗
PubMed2005

Effect of biological additives and micronutrients on the anaerobic digestion of physicochemical sludge.

Two additives (lyophilized bacilli and enzymes) and a solution of micronutrients (Fe, Co, Ni and Mo) were tried separately and in combination, in order to assess their effect on the anaerobic digestion of waste sludge from an enhanced primary treatment (EPT) of municipal wastewater. Three batch tests were carried out in serological bottles. In the first test, addition of bacilli increased production of methane from day 11 and at day 1 7 the production was 95% greater than the control. In that experiment, the concentration of volatile fatty acids (VFAs) was 1,391 mg/L, 40% lower than the control. In the second test, the combination of micronutrients with bacilli, reached from the first days a better methane production than the control, 167% higher in day 17. At the end of the experiment, this combination achieved a lower concentration of VFAs and a greater percentage of volatile solid removal than the rest of the treatments. The third test was based on an experimental design in order to statistically determine the best doses of bacilli additive and micronutrients. The anaerobic thermophilic digestion of sludge from aluminium sulfate EPT will be improved with the addition of Fe: 4.5 mg/g VS, Ni: 0.75 mg/g VS, Co: 0.45 mg/g VS, Mo: 0.09 mg/g VS and bacilli additive: 12 mg/g VS.

Alum Compounds↗
PubMed1990

Addition of 2-nitroimidazole radiosensitizers to cis-diamminedichloroplatinum(II) with radiation and with or without hyperthermia in the murine FSaIIC fibrosarcoma.

We have examined the ability of misonidazole (MISO) or etanidazole (ETA) to improve the antitumor efficacy of cisplatin (CDDP), hyperthermia, and radiation in the FSaIIC murine fibrosarcoma. A growth delay of about 25 days was produced with CDDP (5 mg/kg) and hyperthermia (43 degrees C, 30 min) prior to radiation (3 Gy daily for 5 days) on day 1. The addition of MISO (1 g/kg) on day 1 resulted in a tumor growth delay of about 28 days. The addition of ETA at 0.5 g/kg or 1 g/kg resulted in tumor growth delays of about 33 and 43 days, respectively. Tumor cell survival assay showed that MISO was additive with CDDP either at 37 degrees C or with hyperthermia (43 degrees C, 30 min). In contrast, ETA at both 0.5 g/kg and 1 g/kg was dose modifying over the CDDP dosage range at 37 degrees C or 43 degrees C. Analysis of tumor cell killing in Hoechst 33342 selected bright (presumably oxic) and dim (presumably hypoxic) tumor cell subpopulations demonstrated that the addition of MISO to the CDDP trimodality regimen increased killing in the dim cell subpopulation, while the addition of ETA increased tumor cell killing in both subpopulations, although the greater effect was in the dim cell subpopulation. These results indicate that ETA may add to the efficacy of the CDDP trimodality in the clinic and may be of value as a chemosensitizer with CDDP.

Animals↗
PubMed1990

[Are additional filters made of niobium superior to the copper filter in dental radiology?].

At a dental X-ray unit the effect of an additional filter made of niobium has been tested in the molar region of the mandible with respect to dose reduction. It has been compared against the effect of an additional filter made of copper. With regard to the same dose at the film, radiation dose at the surface of the patient proved to be slightly more reduced after application of the copper filter than after application of the niobium filter. Radiographs have been made by exposure of intraoral dental films (Kodak film Ultra Speed D) together with a hydroxyapatite step-wedge. Measurements of optical density resulted in the same values after application of the copper filter and the niobium filter, respectively. Reduced image contrast due to application of one of these additional filters proved to be helpful. In short, an additional copper filter placed in the X-ray beam shows identical or better results when compared against an additional filter made of niobium.

Copper↗
PubMed1985

Angiotensin converting enzyme inhibition in clinical practice. The second step in "stepped-care": addition or substitution?

The step-wise addition of drugs in stepped-care therapy is based in good part on the need to control different pressor mechanisms in order to lower blood pressure effectively over a long period of time. These mechanisms include the primary mechanisms assumed to be responsible for the hypertensive process and subsequently, either the mechanisms missed by the first drug or the secondary mechanisms evoked by therapy. Although stepped-care therapy has proven effective for many, its rigid application misses the importance of control of systolic blood pressure and of reversal of cardiovascular hypertrophy as additional goals of treatment. Further, the addition of a second drug might mean, in some cases, that an ineffective first drug is continued for no apparent reason. Substitution rather than addition of drugs is a reasonable option. Moreover, the advent of newer drugs with multiple mechanisms of action suggests that a step-wise addition of drugs might not be needed if the list of first step drugs is reviewed with recent advances in mind.

Antihypertensive Agents↗
PubMed1989

Additive diuretic effect of S-8666 during furosemide-induced diuresis in rats.

In order to verify that the novel uricosuric loop-acting diuretic S-8666 has an additional site of action in the distal tubule, we investigated the additive diuretic effect of S-8666 during furosemide-induced diuresis in rats. Intravenous bolus injection of S-8666 (3-30 mg/kg) and trichlormethiazide (TCM) (1-10 mg/kg) caused dose-dependent increases in Na+ excretion during furosemide-induced diuresis (primary, 10 mg/kg i.v.; sustaining, 10 mg/kg/hr i.v.), whereas injection of furosemide (5 mg/kg) did not. Ca++ excretion was decreased by injection of each drug. A significant reduction in Ca++/Na+ was observed at all doses of S-8666 and TCM. Additional natriuretic and hypocalciuric effects were lower in the S-8666 than in the TCM group. From these observations we conclude that: 1) S-8666 has a natriuretic effect which is additive to that of furosemide; 2) S-8666 attenuates the calciuric effect of furosemide; and, 3) S-8666 may have an additional site of action in the distal tubule.

Animals↗
PubMed1987

Moisture permeability mechanisms of some aqueous-based tablet film coatings containing soluble additives.

Moisture permeation parameters--diffusion, solubility and permeation coefficients--for hydroxypropyl methylcellulose (HPMC) and partially hydrolyzed polyvinyl alcohol (PVA) films containing either of two water-soluble additives (citric acid and urea) have been evaluated from transmission and time lag data. Contrary to expectations, the moisture diffusivities of the films were markedly lowered by the presence of these additives. However, the solubility coefficients increased while the permeability coefficients were largely unchanged up to 10 wt% of the additives. A complex phenomenon involving an extensive interlacing network of mainly hydrogen bond interactions between additive and films former was believed to influence the permeation properties of the films. The estimated limits of compatibility of the additives with the film-former were in the range of 5-10 wt%.

Citrates↗
PubMed1986

[Additional images and subsequent palpation--indispensable conditions for efficient diagnosis using mammography].

As adjuvant to standard two-view mammography with craniocaudad and oblique projection additional mammographic views are required to definitely establish a diagnosis in about 30% of patients. These are further views of the entire breast in other planes, repetition of standard mammographic projections, special views of parts of the breast and of the axillary region and tangential spot films. In case of nonpalpable mammographic abnormalities additional views help to study the constancy of the findings (superimposition effect?), the diagnostic significance (occult carcinoma?, parenchymal asymmetry?, benign or malignant microcalcification?) and to determine the topographical position of the lesion. Not uncommonly palpatory findings can be picked up mammographically only by special views, often they require further views in other planes for better delineation of the lesion. The important correlation of palpatory and mammographic findings is frequently possibly only with tangential spot films. Only personal physical examination by the mammographist will ensure the appropriate use of additional mammographic views. This concomitant palpation should be carried out immediately before mammography and especially after completion of mammography while viewing the mammographic images. Additional mammographic views make it possible to improve the diagnostic accuracy of numerous malignant and benign lesions of the breast and of the axilla. Conclusive proof of the benignity of a lesion and thus prevention of an unnecessary biopsy is mostly only possible by means of additional special views. This includes superimposition effects, tumorlike asymmetry, lipomas, fibroadenolipomas and oil cysts all of which amount to 12% of all patients in our material.

Breast Neoplasms↗
PubMed1977

Increased cell-mediated lysis of chicken erythrocytes following the addition of metabolic inhibitors.

The effect of a variety of metabolic inhibitors on the cell-mediated lysis of chicken erythrocytes by immune spleen cells was investigated using the Cr-release assay. The addition of cycloheximide, puromycin, emetine, pactamycin, actinomycin D or EDTA during the early stages of the reaction (0-2 h) produced partial to complete inhibition of the cytotoxic reaction, while the addition of these compounds at later time periods (2-4 h) resulted in the progressive loss of inhibitory effects. Later additions (4-6 h) of all compounds, except EDTA, resulted in a significant increase in target cell lysis. The ability of these compounds to induce increased cytotoxicity required complete inhibition of protein synthesis and the presence of reactive effector cells. It did not appear to be due to an increase in the rate of 51Cr release from previously damaged target cells, or inhibition of a target-cell repair mechanism dependent on protein synthesis. At least a portion of the increased reactivity was due to effector cell-target cell adhesions which formed after the addition of the inhibitor. The data suggests that the addition of metabolic inhibitors during the later stages of the reaction induced an increase in the efficiency or number of cytotoxic attacks.

Animals↗
PubMed1980

Oxidative phosphorylation in isolated canine myocardial mitochondria. Effects of in vitro volume dilution, lactate, phosphate, and calcium addition, and lactic acidosis.

Oxidative phosphorylation of isolated canine myocardial mitochondria was evaluated after exposure to different concentrations of phosphate (5-50 mM), lactate ion in excess (5-40 mM, pH 7.4), and calcium (50-200 microM), to lactic acidosis (pH 6.3), and to mitochondrial protein dilution (in vitro volume expansion) for 10 min to 8 hr. The influence of phosphate and lactate ion addition, lactic acidosis, and in vitro volume expansion on mitochondrial function were studied in the isolation medium (0.18 M KCl, 0.5% bovine serum albumin (BSA) with or without Tris-EDTA, pH 7.4) prior to evaluation of mitochondrial function in the assay medium (0.25 M sucrose, 10 mM Tris-HCl, and 10 mM inorganic phosphate, pH 7.4). The effect of calcium addition was assessed in the assay medium. The results of these studies demonstrate that each of these interventions detrimentally alters mitochondrial oxidative phosphorylative ability. The most severe mitochondrial function impairment resulted from phosphate (5-50 mM) or calcium (50 or 200 microM) addition, each of which decreased the rate of oxygen consumption by 40% or greater. The mitochondrial functional alterations resulting from the interventions that were studied persisted after their removal, but the detrimental effect of phosphate addition and in vitro volume expansion was partially corrected by the addition of cytochrome c. The data are consistent with the possibility that each of these interventions is capaable of altering mitochondrial function but suggest that phosphate and calcium ion accumulation exert the most important detrimental effect on oxidative phosphsorylation in isolated canine cardiac mitochondria.

Acidosis↗
PubMed1981

[Studies on Au-Ag-Pd-Cu alloys. (Part 3) Effects of additional elements to Au-Ag-Pd-Cu alloys (author's transl)].

In the previous papers, the author pointed out that alloys containing 30 wt% Au, 15-25 wt% Pd and Cu were more favourable for Au-Ag-Pd-Cu quarternary dental alloys. In this paper, the experiments were carried out to find the effects of additional elements and so, Pt, Ir, Os, W, Mo, Cr, Mn, Co, Zn, In, Sn and Si were added to 30 wt% Au-30 wt% Ag-20 wt% Pd-20 wt% Cu alloys ranging 0.1 wt% to 2.0 wt% respectively. Then, tensile strength, elongation, hardness, corrosion resistivity and porosity ratio were tested on these specimen. Results were as follows. 1) The addition of 0.2 wt% Ir, 0.2 wt% Os and 1.0 wt% Co were comparatively effective for the fineness of grain sizes, elongation and tensile strength. 2) The addition of 0.2 wt% W, 1.0 wt% Mo and 0.2 wt% Si showed respectively bad effect for porosities or mechanical properties. 3) The addition of 1.0 wt% Cr, 2.0 wt% Mn, 1.0 wt% Co, 2.0 wt% Zn and 2.0 wt% In were good for the decrease of porosities respectively and showed that the porosity ratio was lower than 0.2%. 4) The additions of 2.0 wt% Zn-1.0 wt% Pt-0.5 wt% Co to Au-Ag-Pd-Cu alloy was especially good and showed 80 kg/mm2 of tensile strength, 5.1% of elongation, 249 of Vicker's hardness number and 0.4% of porosity ratio.

Copper↗
PubMed1980

Liberation of endotoxin from Escherichia coli by addition of antibiotics.

The liberation of endotoxin from Escherichia coli by the addition of antibiotics was investigated using a new method of limulus test, i.e. dry up method. The addition of the bactericidal antibiotic, aminobenzylpenicillin or streptomycin sulfate, to the suspension of Escherichia coli (about 10(6)/ml) increased the concentration of endotoxin in the suspension about eight to nine times during a 3-hour period after the addition of antibiotic accompanying with the concomitant decrease of viable cell counts. The addition of the bacteriostatic antibiotic, tetracycline hydrochloride, also increased the endotoxin level, but this increase was rather mild. On the other hand, in the case of the addition of polymyxin B sulfate, there was no evident increase of the endotoxin level. This ability of polymyxin, i.e. the ability to suppress the elevation of endotoxin levels, was shown when polymyxin in the concentration of more than 2.5 micrograms/ml was added against about 10(6)/ml Escherichia coli and was also shown by the combinational use of polymyxin with aminobenzylpenicillin or streptomycin. Furthermore, the endotoxin-inactivating ability of polymyxin was shown in the study where extracted lipopolysaccharide was used in place of viable cells.

Anti-Bacterial Agents↗
PubMed1995

Feedback activation of factor XI by thrombin in plasma results in additional formation of thrombin that protects fibrin clots from fibrinolysis.

Recently, an alternative pathway for factor XI activation has been described in which factor XI is activated by thrombin. Patients with a factor XI deficiency bleed mostly from tissues with high local fibrinolytic activity. Therefore, the role of thrombin-mediated factor XI activation in both fibrin formation and fibrinolysis was studied in a plasma system. Clotting was induced by the addition of tissue factor or thrombin to recalcified plasma in the presence or absence of tissue-type plasminogen activator, after which clot formation and lysis were measured using turbidimetry. Thrombin-mediated activation of factor XI was found to take place in plasma under physiologic conditions in the absence of a dextran sulfate-like cofactor. At high tissue factor concentrations, no effect of factor XI was seen on the rate of fibrin formation. Decreasing amounts of tissue factor resulted in a gradually increasing contribution of factor XI to the rate of fibrin formation. In addition, thrombin-mediated factor XI activation resulted in an inhibition of tissue-type plasminogen activator-induced lysis of the clot. This inhibition occurred even at tissue factor concentrations at which no effect of factor XI was observed on fibrin formation. Trace amounts of activated factor XI (1.25 pmol/L, representing 0.01% activation) were capable of completely inhibiting fibrinolysis in our system. The inhibitory effect was found to be mediated by thrombin that is additionally generated in a factor XI-dependent manner via the intrinsic pathway and is capable of protecting the clot against lysis. We also observed that formation of additional thrombin continued after the clot had been formed. We conclude that thrombin-mediated factor XI activation can take place in plasma. The presence of factor XI during coagulation results in the formation of additional thrombin within the clot capable of protecting this clot from fibrinolytic attack. The large amounts of thrombin that are formed by the intrinsic pathway via factor XI may play an important role in the procoagulant and thrombogenic state of clots and may therefore have important clinical and therapeutic implications.

Blood Coagulation↗
PubMed1994

Efficacy of additive DMARD therapy in patients with rheumatoid arthritis. Double blind controlled trial using bucillamine and placebo with maintenance doses of gold sodium thiomalate.

OBJECTIVE: To examine the efficacy of the addition of small doses of additional disease modifying antirheumatic drugs (DMARD) to ongoing DMARD treatment [additive DMARD therapy (ADT)]. METHODS: A 3-month prospective, double blind, randomized, placebo controlled study was performed using either 100 mg/day of bucillamine (Buc) or an inactive placebo (P1). Two groups of 12 patients each who had experienced an insufficient benefit from gold sodium thiomalate (GSTM) alone were enrolled in the study. RESULTS: The addition of Buc proved more beneficial than P1 regarding improvement in disease activity (p = 0.0032) and drug usefulness (p = 0.0025). A significant within group improvement was observed in joint swelling count, the Lansbury activity index, erythrocyte sedimentation rate and C-reactive protein. However, the difference in the clinical variables between the 2 groups was minimal. CONCLUSION: The usefulness of ADT was suggested by this trial; however, further confirmation by additional studies is still needed.

Aged↗
PubMed1976

Biosynthesis of chondroitin sulfate. Independent addition of glucuronic acid and N-acetylgalactosamine to oligosaccharides.

Pentasaccharide 6-sulfate and hexasaccharide 6-sulfate were prepared from chondroitin 6-sulfate. Each oligosaccharide was incubated with a chick cartilage microsomal enzyme preparation and UDP [14C] glucuronic acid and/or UDP-N-[3H] acetylgalactosamine. As previously reported by other investigators, a single sugar was added from UDP-[14C] glucuronic acid to the nonreducing end of pentasaccharide 6-sulfate and from UDP-N-[3H] acetylgalactosamine to the nonreducing end of hexasaccharide 6-sulfate. The labeled oligosaccharides were characterized by gel chromatography and degradation by chondroitinase ABC followed by identification of products. The oligosaccharides in concentrations above their Km inhibited chondroitin synthesis on endogenous primers, reinforcing the assumption that the enzymes involved in the additions to exogenous oligosaccharides are the same as those involved in chondroitin polymerization. When either the pentasaccharide 6-sulfate or hexasaccharide 6-sulfate was incubated in reaction mixtures containing both of the sugar nucleotides there was generally growth of oligosaccharide by two or three sugars. With longer incubation under conditions of limiting oligosaccharide concentration, as many as 14 to 16 sugars could be added but no further chondroitin polymerization took place. Addition of each sugar was shown to depend upon the concentration of appropriate acceptor but was otherwise independent of the addition of the alternate sugar. No paired addition of sugars was noted. It was concluded that two specific enzymes are involved in alternate additions of sugars to the oligosaccharides and that the two enzymes have no apparent interaction with one another. It is suggested that the rapid polymerization to form large chondroitin chains which previously has been shown to take place on endogenous primers is facilitated by interaction of the two enzymes with a component of the endogenous primer. This component is not present in the exogenous oligosaccharides since they do not serve in the same fashion as primers for polymerization.

Acetylgalactosamine↗
PubMed1996

[Additional question ("is there anything else...?") in primary health care].

OBJECTIVES: To assess in two General Medicine clinics the use of the formula "Was there anything else?" in connection with patients' additional requests and the question's possible association with other variables. DESIGN: Quasi-experimental. SETTING: Urban Health Centre. PATIENTS: Patients from two lists attending over a two-month period, with the exclusion of scheduled patients without appointments. MEASUREMENTS AND INTERVENTIONS: For one of the months patients were asked: "Was there anything else?" (intervention group) and for the other month, they were not (control group). On each visit variables were recorded: list, doctor (tutor/intern), age, gender, reason for consultation (pathology/burocratic), whether accompanied, waiting time and additional requests (new problems raised at the end of the visit). A bivariant analysis of each of the variables with the variable 'intervention' was made and, after a prior transformation of the variable 'additional requests' into two, was adjusted to a multiple logistic regression model in order to control the confusion. RESULTS: 2,657 attendances were analysed. The variables which were significant for the prediction of additional requests were: intervention, list, age, gender and reason for consultation. CONCLUSIONS: The intervention of the doctor may generate additional requests, although whether this means that the consultation is better organised remains to be assessed.

Adult↗
PubMed1996

Electrolyte addition to nonionic contrast media. Cardiac effects during experimental coronary arteriography.

Although the incidence of serious adverse effects is low during clinical coronary arteriography, life-threatening cardiovascular complications occasionally occur. Ventricular fibrillation (VF) is most often seen during contrast media (CM) injection through a wedged catheter. A simulated wedged catheter model in dogs has therefore been developed. Further, patients with heart failure are at greater risk for CM-related side effects during coronary arteriography. Thus, an acute ischemic heart failure model has been used. The present thesis was designed to investigate the cardiac electrophysiologic and hemodynamic effects of CM during selective coronary arteriography in normal and failing hearts, and in particular the role of electrolyte addition to nonionic CM. The risk of spontaneously induced VF and the arrhythmogenic mechanisms were studied when using iso-osmolal and low-osmolal CM having different contents of electrolytes, and after pretreatment with antiarrhythmic drugs. Further, effects of adding electrolytes to nonionic CM during single and fast repeated injections in normal and failing hearts were studied. Also possible effects of oxygenating CM were studied. CM injection in a wedged catheter situation had a high risk for VF. Probably, VF was due to induced regional electrophysiologic changes in ventricular activation and repolarization. Pretreatment with antiarrhythmic drugs did not prevent VF. However, addition of low concentrations of electrolytes to nonionic CM reduced the risk for VF in a wedged catheter situation. The results indicate that side-effects of CM during coronary arteriography are related mainly to the passive washout of cardiac electrolytes. Electrolyte shifts during coronary arteriography may change the myocardial Na/Ca balance and cellular calcium control. The nonionic, iso-osmolal CM iodixanol, with a balanced content of sodium and calcium and the low-osmolal, nonionic CM iohexol, also with a balanced content of electrolytes, had about the same low risk for inducing VF and presented a much lower risk for inducing VF than did iohexol and ioxaglate in a wedged catheter situation. Single injection of iohexol with a balanced eletrolyte addition induced only minimal electro-physiologic changes and was well tolerated hemodynamically. Repeated intracoronary CM injections during ischemic heart failure were associated with similar additive electrophysiologic and hemodynamic changes as when using iohexol without electrolyte supplement. Oxygenated and nonoxygenated CM presented the same risk for inducing VF. Only minor electrophysiologic and hemodynamic differences could be detected during wedged catheter injection. In conclusion, addition of key electrolytes to nonionic CM can reduce the risk of cardiac complications during coronary arteriography. Oxygenation of CM does not seem to significantly further reduce the risk.

Animals↗