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The capture of heavy metals from incineration using a spray dryer integrated with a fabric filter using various additives.

This study investigated the effects of feedstock additives [polyvinyl chloride (PVC) and NaCl] and spray dryer additives (SiO2, CaCl2, NaHCO3) on heavy metal and fly ash removal efficiencies, and on particle size distribution of heavy metals. A spray dryer with an integrated fabric filter was used as an air pollution control device (APCD). Removal efficiencies for fly ash and heavy metals were greater than 95 and 90%, respectively. When additives of PVC or NaCl were used, the concentration of heavy metals distributed in fly ash apparently varied when the particle diameter was <1 microm. Although the effects of the additives SiO2, CaCl2, and NaHCO3 on the elemental size distribution of Cr were insignificant, these additives did slightly increase concentrations of Cd, Zn, and Pb partitioning in coarser particles (>1 microm).

Air Pollutants↗

Industry research on the use and effects of levulinic acid: a case study in cigarette additives.

Public health officials and tobacco researchers have raised concerns about the possible contributions of additives to the toxicity of cigarettes. However, little attention has been given to the process whereby additives promote initiation and addiction. Levulinic acid is a known cigarette additive. Review of internal tobacco industry documents indicates that levulinic acid was used to increase nicotine yields while enhancing perceptions of smoothness and mildness. Levulinic acid reduces the pH of cigarette smoke and desensitizes the upper respiratory tract, increasing the potential for cigarette smoke to be inhaled deeper into the lungs. Levulinic acid also may enhance the binding of nicotine to neurons that ordinarily would be unresponsive to nicotine. These findings held particular interest in the internal development of ultralight and so-called reduced-exposure cigarette prototypes. Industry studies found significantly increased peak plasma nicotine levels in smokers of ultralight cigarettes following addition of levulinic acid. Further, internal studies observed changes in mainstream and sidestream smoke composition that may present increased health risks. The use of levulinic acid illustrates the need for regulatory authority over tobacco products as well as better understanding of the role of additives in cigarettes and other tobacco products.

Enzyme Inhibitors↗

[Improvement of the feed value of straw by pelleting and sodium hydroxide addition. 1. Changes in the digestibility of rye and wheat straw].

Four series of pelleting experiments were conducted using straw from winter rye and winter wheat crops. Pelleting was done with and without grain addition. In each of the experimental series, 7 NaOH dosage levels were tested Further, 2 to 5% urea were added to the mixture to be pelleted. The 28 different pellet batsches and untreated straw were fed to sheep to study digestibility. Evaluation by difference trial revealed that straw pelleting without NaOH addition reduces the digestibility of organic matter by 4.7 units, on the average, whilst NaOH addition was found to increase digestibility depending on the dose applied. The following relationship was found between digestibility of straw dry matter (y) and NaOH dose in g/kg straw dry matter (x): y = 43.4 + 0.358x -0.00116x2. The grain proportion proved largely inert as far as the NaOH action is concerned. In one experimental series in which wheat straw without grain addition had been compacted at high pressing temperatures, an additional disintegration effect was observed irrespective of the NaOH dose applied. It increased digestibility by 8.0 units and is very likely to originate from the specific action of urea.

Animal Feed↗

Storage and retrieval of addition facts: the role of number comparison.

It is proposed that arithmetical facts are organized in memory in terms of a principle that is unique to numbers--the cardinal magnitudes of the addends. This implies that sums such as 4 + 2 and 2 + 4 are represented, and searched for, in terms of the maximum and minimum addends. This in turn implies that a critical stage in solving an addition problem is deciding which addend is the larger. The COMP model of addition fact retrieval incorporates a comparison stage, as well as a retrieval stage and a pronunciation stage. Three tasks, using the same subjects, were designed to assess the contribution of these three stages to retrieving the answers to single-digit addition problems. Task 3 was the addition task, which examined whether reaction times (RTs) were explained by the model; Task 1 was a number naming task to assess the contribution of the pronunciation stage; Task 2 was a magnitude comparison task to assess the contribution, if any, of the comparison stage. A regression equation that included just expressions of these three stages was found to account for 71% of the variance. It is argued that the COMP model fits not only the adult RT data better than do alternatives, but also the evidence from development of additional skills.

Adult↗

Solutol and cremophor products as new additives in suppository formulation.

Our research has a double purpose. On the one hand, doctors have expressed the need to formulate a rectal suppository dosage form from diuretic ethacrynic acid, which would add to the choice of treatment methods and thereby increase the possibilities of individual cure. On the other hand, the liberation and thereby the bioavailability of poorly-soluble ethacrynic acid needs to be enhanced, and for this purpose solubility-increasing additives new to rectal therapy were used. Solutol HS 15, Cremophor RH 40, and Cremophor RH 60 were used as additives in concentrations of 1, 3, 5, and 10%. The quantity of drug released changed as a function of additive concentration. Depending on the acceptor phase, the best results were achieved with an additive concentration of 1-3%, which is related to the optimal additive quantity accumulated on the boundary surface.

Biological Availability↗

Site of addition of N-acetyl-galactosamine to the E1 glycoprotein of mouse hepatitis virus-A59.

By pulse-chase labeling with [35S]methionine and long-term labeling with 3H-sugars, the E1 glycoprotein of coronavirus MHV-A59 has been shown to acquire O-linked oligosaccharides in a two-step process. About 10 min after synthesis of the E1 protein, N-acetyl-galactosamine was added. This was followed approximately 10 min later by the addition of both galactose and sialic acid to give the mature oligosaccharides. This sequence of additions was confirmed by analyzing the 3H-labeled oligosaccharides bound to each of the E1 forms using gel filtration on P4 columns. The intracellular location of the first step was determined by exploiting the temperature sensitivity of virus release. The virus normally buds first into a smooth membrane compartment lying between the rough endoplasmic reticulum and the cis side of the Golgi stack (Tooze et al., 1984). At 31 degrees C the virus is assembled but does not appear to enter the Golgi stacks. The addition of N-acetyl-galactosamine is unaffected although the addition of galactose and sialic acid is inhibited. These results strongly suggest that addition of N-acetyl-galactosamine occurs in this budding compartment, the morphology of which is similar to that of transitional elements and vesicles.

Acetylgalactosamine↗

Addition of fibronectin to alginate matrix improves peripheral nerve regeneration in tissue-engineered conduits.

Schwann cell (SC) transplantation has been proposed to encourage peripheral nerve regeneration, but an optimal SC-carrying matrix would be needed. The aim of this study was to characterize how the addition of fibronectin to alginate would affect the outcome of nerve regeneration promoted by Schwann cells embedded in this matrix. Genetically labeled rat SCs were obtained by lacZ gene transduction. SCs were suspended in alginate hydrogel matrix with/without addition of liquid fibronectin, and their viability and growth in the different types of matrices were assessed in vitro by AlamarBlue assay. In vivo assessment of SC transplantation in the matrix was carried out with poly-3-hydroxybutyrate (PHB) conduits to bridge a sciatic nerve gap. The grafted conduits were harvested at 2, 3, and 6 weeks and assessed for the presence of labeled SCs in relation to regrowing axons. The amount and rate of axonal regeneration were assessed by quantitative immunohistochemistry. Addition of fibronectin to alginate hydrogel improved SC viability and growth profile in vitro. X-Gal staining confirmed that SCs transplanted in PHB conduits were viable throughout the time course, and that the labeled SCs were clearly associated with regenerating axons. The regeneration rate was enhanced when liquid fibronectin was added to the alginate matrix. Furthermore, the presence of SCs also enhanced regeneration and there was an additive effect when both SCs and fibronectin were combined with alginate. In conclusion, the addition of fibronectin to alginate hydrogel matrix contributed to improve nerve regeneration, supporting SC viability and augmenting their effect on axonal growth when transplanted in a bioengineered nerve conduit.

Alginates↗

Effects of graded sucrose additions on taste preference, acceptability, glycemic index, and insulin response to butter beans.

Dried beans, because of their high-fiber content and low-glycemic index, are especially suitable for diabetic diets. Most South African bean recipes contain sucrose, and since a restriction of artificial sweeteners seems desirable, replacing sucrose would be impractical. Hence, we examined the effects of 10, 20, and 30% sucrose additions to cooked dried butter beans on taste preference and acceptability in 29 diabetic patients and 11 control subjects. The effect of sucrose additions on glycemic index and insulin response to butter beans was determined in control subjects. Both diabetic and control subjects preferred beans with sucrose additions (p less than 0.005). Additions of sucrose up to 20% of total carbohydrate had no adverse effects on glycemic index or insulin response of butter beans (p less than 0.05), which indicates that addition of moderate amounts of sucrose to a low glycemic index food may improve palatability without impairing the favorable effect on blood glucose and insulin response.

Adult↗

Production and characterization of maize chromosome 9 radiation hybrids derived from an oat-maize addition line.

In maize (Zea mays L., 2n = 2x = 20), map-based cloning and genome organization studies are often complicated because of the complexity of the genome. Maize chromosome addition lines of hexaploid cultivated oat (Avena sativa L., 2n = 6x = 42), where maize chromosomes can be individually manipulated, represent unique materials for maize genome analysis. Maize chromosome addition lines are particularly suitable for the dissection of a single maize chromosome using radiation because cultivated oat is an allohexaploid in which multiple copies of the oat basic genome provide buffering to chromosomal aberrations and other mutations. Irradiation (gamma rays at 30, 40, and 50 krad) of a monosomic maize chromosome 9 addition line produced maize chromosome 9 radiation hybrids (M9RHs)-oat lines possessing different fragments of maize chromosome 9 including intergenomic translocations and modified maize addition chromosomes with internal and terminal deletions. M9RHs with 1 to 10 radiation-induced breaks per chromosome were identified. We estimated that a panel of 100 informative M9RHs (with an average of 3 breaks per chromosome) would allow mapping at the 0. 5- to 1.0-Mb level of resolution. Because mapping with maize chromosome addition lines and radiation hybrid derivatives involves assays for the presence or absence of a given marker, monomorphic markers can be quickly and efficiently mapped to a chromosome region. Radiation hybrid derivatives also represent sources of region-specific DNA for cloning of genes or DNA markers.

Avena↗

Non-additivity of sequence-specific enzyme-DNA interactions in the EcoRI DNA methyltransferase.

We describe a novel strategy to characterize protein-DNA interactions involving monomeric enzymes such as DNA methyltransferases (Mtases). This strategy is applied to our investigation of the EcoRI DNA Mtase, which binds its double stranded recognition site 5'-G-AATTC-3' and methylates the central adenosine of each strand using S-adenosyl-L-methionine as the methyl donor. We show that prior methylation of adenosine in either strand does not perturb catalysis. In contrast, substrates substituted with deoxyinosine at either guanosine position (T-BMI5 and TI5-BM) show the minor groove residing N2 amino group of both guanosines contribute to DNA recognition since specificity constants for the modified substrates are reduced 13 and 39 fold. Similar analysis of a substrate containing deoxyinosine at both positions (TI5-BMI5) clearly shows that some communication occurs between the sites. To determine the extent to which structural changes in the DNA alone contribute to this lack of additivity, we performed DNA melting analysis of the singly and doubly substituted substrates, and also found non-additivity. Although our functional and structural analyses suggest that deoxyinosine incorporation causes long range conformational effects, the similarity of KmAdoMet for all substrates suggests that no large-scale structural changes occur in the Mtase-DNA-AdoMet complex. Our results support the following conclusions: 1) The non-additivity shown in this system contrasts with the widespread demonstration of additivity involving repressors [Lehming et al., 1990; Takeda et al., 1989; Ebright et al., 1987], suggesting that sequence discrimination by enzymes may involve more complex mechanisms. Further, this non-additivity precludes quantitative assignment of individual interactions and we suggest that future analyses of this and related enzyme systems with base analogs include detailed information about the long range structural consequences of individual substitutions. 2) Although TI5-BM and T-BMI5 are shown to be radically different by thermodynamic analysis, the similar specificity constants with the Mtase suggest that the underlying structural differences (e.g., altered helical parameters of the DNA) are not critical for sequence-recognition. 3) The significance of minor groove Mtase-DNA interactions to specificity is confirmed.

Base Sequence↗

Yeast telomerase is capable of limited repeat addition processivity.

Telomerase is a ribonucleoprotein reverse transcriptase responsible for the maintenance of one strand of telomere terminal repeats. Telomerase-mediated sequence addition is dictated by a short 'template' region of the RNA component. Despite the short template segment, telomerases from many organisms have been shown to mediate the synthesis of long extension products. This synthesis presumably depends on two types of translocation events: simultaneous translocation of the RNA-DNA duplex relative to the active site after each nucleotide incorporation (type I or nucleotide addition processivity), and translocation of the RNA relative to the DNA product after each round of repeat synthesis (type II or repeat addition processivity). In contrast, telomerases from yeasts have been shown to synthesize mostly short products, implying a defect in one or both types of translocation. In this report, we analyzed the processivity of yeast telomerase in vitro, and identified two position-specific elongation barriers within the 5' region of the RNA template that can account for the synthesis of incomplete first round products. These barriers respond differently to variations in nucleotide concentration, primer sequence and mutations in the catalytic protein subunit, consistent with their having distinct mechanistic bases. In addition, by using optimal primers and high concentrations of dGTP, we were able to detect significant type II translocation by the yeast enzyme. Thus, the difference between the elongation property of yeast and other telomerases appears to be quantitative rather than qualitative. Our results suggest that yeast may be a useful system for investigating the physiologic significance of repeat addition processivity.

Base Sequence↗

Modifications of substituted seryl and threonyl residues in phosphopeptides and a polysialoglycoprotein by beta-elimination and nucleophile additions.

The beta-elimination and nucleophile addition reactions of the substituted serine and threonine residues were studied using several synthesized fluorescence-labeled phosphopeptides and a salmon egg polysialoglycoprotein (PSGP). The reagents used were 1 M CH3SH-0.43 M NaOH, 1 M NaBH4-0.1 M NaOH, 1 M CH3NH2-0.1 M NaOH, and 1 M Na2SO3-0.1 M NaOH. The beta-elimination reaction of a phosphoserine peptide, Gly-Ser(PO4)-Glu-AEAP, was about 20 times faster than that of the corresponding phosphothreonine peptide. The carboxyl-side amino acid of the phosphoamino acids in peptides greatly affected the beta-elimination rate. The beta-elimination reaction rates of O-glycosyl serine and threonine in the polysialoglycoprotein were similar and were about a half of that of the phosphoserine peptide. The rates of addition of the three nucleophiles and hydrogen to alpha-aminoacrylic acid (beta-elimination product of substituted serine) in the peptide decreased in the order of CH3SH, Na2SO3, CH3NH2, and H2(NaBH4), and the addition to alpha-aminocrotonic acid (beta-elimination product of substituted threonine) in the order of Na2SO3, CH3NH2, CH3SH, and H2. These results indicated that sulfite is the most recommended nucleophile because of its high addition rate. If sulfite addition is carried out in the presence of NaBH4, sugar chains can be released as alditols, converting the sugar-attaching amino acids to beta-sulfoamino acids.

Amino Acid Sequence↗

The effect of the addition of epinephrine on early systemic absorption of epidural ropivacaine in humans.

UNLABELLED: The addition of epinephrine to ropivacaine has not been recommended because ropivacaine has intrinsic vasoconstrictor properties. However, few pharmacokinetic data are available on the addition of epinephrine to epidural ropivacaine in humans. In this prospective, double-blinded study, we randomized patients having elective abdominal hysterectomy to receive epidural ropivacaine 1.5 mg/kg, diluted in 15 mL, either with (epinephrine group, n = 12) or without (plain group, n = 12) epinephrine 5 microg/mL and then measured arterial and venous plasma concentrations of ropivacaine at intervals up to 180 min. We found that arterial and venous plasma ropivacaine concentrations were smaller in the epinephrine group compared with the plain group in the first 60 min after the drug administration (P < 0.01). Mean (+/- SD) maximum total plasma ropivacaine concentration was smaller in the epinephrine group (arterial, 0.92 +/- 0.32 microg/mL; venous, 0.82 +/- 0.33 microg/mL) compared with the plain group (1.31 +/- 0.39 microg/mL and 1.31 +/- 0.50 microg/mL, respectively; P = 0.01). Time to maximum total plasma ropivacaine concentration was not significantly different between groups (mean +/- SD; arterial, 16 +/- 2 min; venous, 23 +/- 2 min in the epinephrine group versus 9 +/- 2 min and 12 +/- 3 min, respectively, in the plain group; P = 0.08). Arterial plasma ropivacaine concentrations were larger than venous concentrations during the first hour (P < 0.01); the arterio-venous difference decreased exponentially, and the rate and magnitude of this decrease was unaffected by epinephrine. We conclude that the addition of epinephrine 5 microg/mL to ropivacaine reduced the early systemic plasma concentrations of ropivacaine after epidural injection and may be useful for decreasing the risk of toxicity from systemic absorption of epidural ropivacaine. IMPLICATIONS: The addition of epinephrine 5 microg/mL to epidural ropivacaine reduced the systemic arterial and venous plasma concentrations of ropivacaine in the first hour and the maximum plasma concentration of ropivacaine. Epinephrine may be a useful additive for reducing the risk of systemic toxicity when large doses of ropivacaine are given epidurally.

Adult↗

Volatile anesthetic additivity and specificity in Saccharomyces cerevisiae: implications for yeast as a model system to study mechanisms of anestheitc action.

BACKGROUND: In animals, combinations of volatile anesthetics are additive for inducing anesthesia. Furthermore, although there is a correlation between lipophilicity and anesthetic potency, not all volatile lipophilic compounds are anesthetic. Previously the authors demonstrated the effects of volatile anesthetics on the eukaryote Saccharomyces cerevisiae (yeast). To further relate anesthetic action in this organism to mammals, anesthetic additivity and effects of volatile, lipophilic nonanesthetics were studied. In addition, yeast pleiotropic drug-resistance (Pdr) mutants, which confer resistance to various lipophilic compounds, were tested to determine if they are involved in anesthetic response. METHODS: Yeast strains were grown to saturation in liquid culture, diluted, plated on various solid media, incubated, and scored for growth. RESULTS: Combinations of volatile anesthetics inhibit growth of wild-type (Zzz+) but not anesthetic-resistant (Zzz-) strains when additive concentrations equal 1 minimum inhibitory concentration (MIC). Two volatile, lipophilic compounds that are nonanesthetic in mammals do not inhibit yeast growth. Zzz- mutants remain sensitive to drugs used to identify yeast PDR genes. Conversely Pdr strains, which are resistant to various lipophilic compounds, remain sensitive to volatile anesthetics. CONCLUSIONS: Yeast growth is inhibited in an additive manner by volatile anesthetics. Volatile, lipophilic compounds devoid of anesthetic activity in mammals do not inhibit yeast growth. Zzz- mutants appear to be specifically resistant to volatile anesthetics and distinct from known Pdr mutants. These results suggest that volatile anesthetics behave in a parallel manner in yeast and mammals, making yeast a useful model to investigate the molecular effects of these compounds in living cells.

Anesthetics, Inhalation↗

Additional intravitreal gas injection in the early postoperative period for an unclosed macular hole treated with internal limiting membrane peeling.

PURPOSE: To study the efficacy of additional intravitreal gas injection for unclosed macular holes within 2 weeks after surgery with internal limiting membrane peeling. METHODS: We reviewed the results for five consecutive eyes receiving additional intravitreal gas injection for unclosed macular holes within 2 weeks after initial macular hole surgery with internal limiting membrane peeling. The initial surgery consisted of standard pars plana vitrectomy with phacoemulsification and intraocular lens implantation, indocyanine green-assisted peeling of the retinal internal limiting membrane, and fluid-gas exchange with 20% sulfur hexafluoride. The patients were instructed to assume face down positioning for > or =7 days after surgery. If an unclosed macular hole was found after the residual gas volume decreased to <30% of the eyeball volume, fluid-gas exchange was performed using 15% octafluoropropane. RESULTS: All five eyes receiving additional intravitreal gas 7 to 14 days after vitrectomy had complete macular hole closure with macular flattening, as shown by optical coherence tomography 1 month after the additional gas injection. Visual acuity improved (range, 20/100 to 20/30). A minimum of 9 months of follow-up revealed no reopening or serious complications. CONCLUSION: Additional gas injection during the early postoperative period is recommended for eyes with unclosed macular holes that have undergone vitrectomy with internal limiting membrane peeling.

Aged↗

The CDKN2A tumour suppressor gene: no mutations detected in patients with melanoma and additional unrelated cancers.

Germ-line mutations of the CDKN2A tumour suppressor gene have been reported in association with familial melanoma, sporadic melanoma with multiple primary lesions and also pancreatic cancer. We studied the hypothesis that patients with melanoma and additional unrelated cancers may harbour mutations in the CDKN2A gene. Twenty seven patients with histologically confirmed melanoma who also had additional cancers such as breast, colorectal, lymphoma and other neoplasms were studied. We also examined 17 additional patients, 13 of whom had a first-degree relative with melanoma and four who had two or more primary melanomas. Some patients belonged to more than one of these categories. No mutations of the CDKN2A tumour suppressor gene were detected among patients with melanoma and additional cancers. The previously described Met53Ile CDKN2A mutation located in exon 2 was detected in a female patient with melanoma metastatic to the regional lymph nodes, multiple primary cutaneous lesions, atypical naevi and a first-degree relative with melanoma. The studied cohort is too small for firm conclusions. However, it would appear that melanoma and additional, apparently unrelated, cancers developing in the same individual are likely to be related to a combination of low-risk susceptibility genes and environmental factors.

Adult↗

Medication usage and additional esophageal procedures after antireflux surgery.

One of the goals of antireflux surgery (ARS) is to lower medications usage for heartburn symptoms. There has been some controversy as to whether this is accomplished by surgery. In addition, there is little comparative data of medical usage in patients suffering from gastroesophageal reflux disease (GERD) treated nonoperatively with those treated with surgery, and no data on additional esophageal procedures, such as upper endoscopy or dilation. The purpose of this study was to determine these differences in a matched group of medically and surgically treated patients with at least 1 year of follow-up. All patients who underwent ARS with at least 1 year of follow-up were included. These patients were matched to a group of medically treated patients for gender, age, and month of surgery to month of gastroenterologic clinic visit. Information was gathered through the medical record or direct contact for the present use of medications and additional esophageal procedures related to GERD. One hundred twenty-two patients in each group were studied. Medication usage consisted of 13% of ARS patients versus 95% of medical patients (P < 0.0001). ARS patients had used 359 patient-months of medications versus 3578 in the medical group (P < 0.0001). Only 25% of ARS patients prescribe medications actually responded to their use. Additional procedures consisted of 9% of ARS patients versus 64% of medical patients (P < 0.0001). In conclusion, ARS leads to decreased medication use and to decreased use of subsequent esophageal procedures. In addition, most postoperative ARS patients placed on medications do not respond, and therefore require an objective evaluation for their symptoms.

Antacids↗

Effects of additional oxazepam in long-term users of oxazepam.

Although additional dosages of benzodiazepines in long-term users of benzodiazepines are common, it is unknown whether these additional dosages resort any effect. The effects of an additional 20-mg dosage oxazepam were assessed in a double-blind, balanced-order, crossover randomized study comparing 16 long-term users of oxazepam (patients) with 18 benzodiazepine-naive controls (controls). The effects of 10 and 30 mg oxazepam were assessed at pretest and 2.5 hours after drug administration on: (a) saccadic eye movements as proxy for the sedative effect, (b) acoustic startle response (ASR) as proxy for the anxiolytic effects, (c) memory, (d) reaction time tasks, and (e) subjective measurements. Dose-related effects were found in patients on the peak velocity of saccadic eye movement and on response probability, respectively peak amplitude of the ASR. Comparison with controls, however, suggests that in patients the sedative effects might be mixed up with suppression of sedative withdrawal symptoms, whereas patients were as sensitive as benzodiazepine-naive controls for the effects of an additional dosage on the ASR. Neither 10 nor 30 mg oxazepam challenge affected the reaction time tasks in patients, whereas controls show a dose-related impairment. The memory impairing effects, however, did not differ significantly between patients and controls. In contrast to controls, patients could not discriminate between a 10- and 30-mg dosage as assessed by visual analogue scales and the STAI-DY-1, which might indicate a placebo effect in the 10-mg challenge in patients. We conclude that additional dosages of oxazepam still exert pronounced effects after daily use for more than 10 years.

Adult↗