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PubMed2000

Additive immunosuppressive effects of 1,25-dihydroxyvitamin D3 and corticosteroids on TH1, but not TH2, responses.

BACKGROUND: The biologic role of the vitamin D analogue 1, 25-dihydroxyvitamin D(3), such as antiinflammatory functions, reduction of cytokine production by T cells, and immunoglobulin production by B cells, has been reported. Such immunomodulatory effects may be potentially useful in dealing with autoimmunity and transplantation. However, whether this hormone has an additive immunosuppressive effect when it is used with corticosteroids has not been investigated, although these agents are commonly used together. OBJECTIVE: Our purpose was to investigate the additive immunomodulatory effects of 1,25-dihydroxyvitamin D(3) on lymphocyte proliferation and cytokine production when used with corticosteroids. METHODS: To investigate the additive effects of 1, 25-dihydroxyvitamin D(3) and dexamethasone on suppression of lymphocyte proliferation, normal PBMCs were cultured in anti-CD3 with or without different concentrations of dexamethasone (0-10(-7) mol/L) plus or minus different concentrations of 1, 25-dihydroxyvitamin D(3) (0-10(-6) mol/L). After 3 days, lymphocyte proliferation was assessed by [(3)H]-thymidine incorporation. To investigate the additive effects of 1,25-dihydroxyvitamin D(3) and dexamethasone on cytokine production, PBMCs were cultured for 3 days in the presence of anti-CD3 with or without 10(-6) mol/L dexamethasone plus or minus 10(-6) mol/L 1,25-dihydroxyvitamin D(3). IFN-gamma, IL-5, and IL-13 production in supernatants were measured by ELISA. RESULTS: Our study demonstrated that, at concentrations of 10(-8), 10(-7), and 10(-6) mol/L, 1,25-dihydroxyvitamin D(3) significantly decreased lymphocyte proliferation compared with an ethanol control (P <.05). The IC(50) for dexamethasone was 4 x 10(-9) mol/L in culture without 1,25-dihydroxyvitamin D(3.) When 10(-9) mol/L of 1,25-dihydroxyvitamin D(3) was added to cultures with dexamethasone, IC(50) became 2 x 10(-9) mol/L. Moreover, when 10(-6), 10(-7), and 10(-8) mol/L of 1,25-dihydroxyvitamin D(3) were added in culture with dexamethasone, IC(50) became less than 1 x 10(-9) mol/L. IFN-gamma production in culture with either dexamethasone or 1,25-dihydroxyvitamin D(3) was significantly decreased compared with media or ethanol control (P <.0001). Moreover, when both agents were added in the same culture, IFN-gamma production was further decreased compared with either agent alone (P <.05). In contrast, 1,25-dihydroxyvitamin D(3) significantly (P <. 0001) increased IL-5 and IL-13, whereas dexamethasone significantly decreased these 2 cytokines (P <.0005). When 1,25-dihydroxyvitamin D(3) was combined with dexamethasone, IL-5 and IL-13 production was increased compared with dexamethasone alone (P <.001). CONCLUSIONS: Our results demonstrate that 1,25-dihydroxyvitamin D(3) has significant additive effects on dexamethasone-mediated inhibition of lymphocyte proliferation. This hormone also has additive effects on inhibition of T(H)1 cytokine production when combined with dexamethasone. However, this hormone upregulates T(H)2 cytokines and inhibits steroid-mediated suppression of cytokines. These findings demonstrate the potential use of 1,25-dihydroxyvitamin D(3) as an immunosuppressive agent when combined with corticosteroids in T(H)1, but not T(H)2, immune responses.

Anti-Inflammatory Agents↗
PubMed1987

Urea synthesis and leucine turnover in growing pigs: changes during 2 d following the addition of carbohydrate or fat to the diet.

1. Studies have been made of the time-sequence of protein metabolic and hormonal changes following an abrupt increase in carbohydrate or fat intake. [3H]leucine and [14C]urea were infused for 72 h, via the aorta, into fourteen female pigs (30-38 kg body-weight). At 24 h after the start of the infusion their feed was either changed to one of two isonitrogenous diets containing additional starch (group BS, five animals) or fat (group BF, five animals), or remained unaltered (group BB, four animals). The distribution space of urea was measured by the dilution of a single dose of [14C]urea given both 48 h before and 48 h after the change in diet. The changes in the concentration and specific radioactivity of blood leucine were used to infer changes in protein turnover and those of plasma urea to measure total amino acid catabolism. The concentrations of blood glucose and plasma insulin and cortisol were also measured at approximately two-hourly intervals for the 48 h period following the change in diet. 2. Within 4 h of either change in diet blood leucine concentration was lowered and the leucine specific radioactivity was raised above that in group BB, but after 24 h both the concentration and specific radioactivity of leucine returned to values similar to those in group BB. Eventually the blood leucine specific radioactivity was slightly but not significantly reduced below that of group BB. 3. The addition of starch to the diet significantly reduced the synthesis and concentration of urea within 4 h but, although the addition of fat to the diet eventually lowered the urea concentration and synthesis, both changes were delayed for 18-24 h. 4. In group BS plasma glucose and insulin rose after the addition of starch, but after 24-36 h both returned to values that were the same as those in the animals that received the same diet throughout (group BB). The addition of fat to the diet altered neither blood glucose nor plasma insulin concentrations. The addition of either carbohydrate or fat to the diet eventually reduced plasma cortisol concentrations, but the change did not occur until 24 h after the change in diet. 5. The results suggest that alterations in non-protein energy supply exert their immediate effect on the degradation of whole-body protein. They do not exclude the possibility that these early changes may reflect opposing changes at different sites.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1998

Stability testing of the plastics additives 2,4-dihydroxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octyloxybenzophenone, 2-ethoxy-2-ethyloxanilide (tinuvin 312) and 2,2'-methylenebis(4-methyl-t-tert-butyl phenol) in aqueous and fatty food simulants.

The stability of five additives used in the manufacture of plastics materials intended to be in contact with foodstuffs was tested in two EU aqueous food simulants (3% acidic acid and 15% ethanol), in olive oil and in two alternative fatty food simulants (95% ethanol and isooctane) under various conditions of temperature and time established for migration testing. The additives were the following: 2,4-dihydroxybenzophenone, 2-2'-dihydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octyloxybenzophenone, 2-ethoxy-2-ethyloxanilide and 2,2'-methylenebis(4-methyl-6-tert-butyl phenol). The additives were spiked into the simulants at their anticipated Specific Migration Limit (SML) and submitted to time-temperature conditions used in the migration testing. The test samples were analysed against fresh samples of the additives spiked at the same concentration just before the analysis. All samples were analysed with HPLC, using an ODS2 column and mobile phase of methanol-water or acetonitrile-water. The results were statistically evaluated by applying a two-tailed F-test (at 95% confidence level) to the variances and onetailed t-test (at 90% confidence level) to the means of the control and the test samples. The statistical evaluation of the results showed that the additives were stable in all simulants within the statistical allowances. Only the 2.2'-methylenebis(4-methyl-6-tert-butyl phenol) showed a loss of about 20% in olive oil and 17% in 3% aqueous acetic acid. The results of the study will be used by the Commission, DG III-C-I. to help to determine whether legislative restrictions in the additives Directive should be applied to the finished material or article (QM) or to migration to simulants (SML).

Benzophenones↗
PubMedDate not supplied

The use of additives to modulate the release of a sparingly water soluble drug entrapped in PLA50 microparticles.

One of the major problems raised by the microencapsulation of drugs which are sparingly soluble in water is the difficulty to achieve a controlled and total release of the drug. It was previously shown that the microencapsulation of a model water insoluble drug, namely 1-[2-(4-fluorobenzoyl)aminoethyl]-4-(7-methoxynaphthyl) piperazine hydrochloride (FAMP) with a hydrophilic additive like low molar mass poly(ethylene glycol)s (PEG) can fulfil these requirements, provided all the drug + additive matter is in contact with the surrounding liquid medium via open pores and percolating channels. In this paper, PEG was replaced by other additives, selected because of their potential ability to increase the solubility of FAMP in pH = 7.4 isosomolar phosphate buffer (PBS). The idea was that increasing the solubility locally in microparticles could allow the drug to be released, despite its poor solubility in aqueous media like body fluids, and be absorbed before recrystallization. The solubility in PBS of FAMP mixed with additive, in the form of solid dispersions, was determined for various additives, namely citric acid, dimyristoyl DL-alpha-phosphatidyl choline (DMPC), poloxamer copolymers of different compositions and poly(dodecyl L-lysine citramidate) (PLCAC12(100)), an aggregate-forming hydrophilic polyelectrolyte containing 100%, hydrophobizing ester groups which can accommodate lipophilic compounds in hydrophobic pockets present in the aggregates. PEG was taken as a reference. It was found that DMPC, some poloxamers and the hydrophobized polyelectrolyte do increase the solubility of FAMP in PBS. Investigation was made of the release of FAMP from ground microparticles, whose loads were composed of FAMP combined with these solubilization-promoting additives. It was found that the release rate of FAMP from such systems can be increased and modulated to achieve an in vitro sustained release over a 20-30 day period and secure exhaustion of the particles at the end of this period.

Benzamides↗
PubMedDate not supplied

Effects of salt addition on the microencapsulation of proteins using W/O/W double emulsion technique.

The influence of co-encapsulation of stabilizing additives together with BSA on microsphere characteristics using the modified water-in-oil-in-water emulsion solvent evaporation (W/O/W) method was investigated. For this purpose, poly(L-lactide) microspheres containing bovine serum albumin (BSA) were prepared. The morphology, porosity, specific surface area, particle size, encapsulation efficiency and kinetics of drug release of protein loaded microspheres were analysed in relation to the influence of co-encapsulated stabilizing additives such as electrolytes. High salt concentrations in the internal (W1) aqueous phase, often necessary to stabilize protein or antigen solutions, led to an increase in particle size, particle size distribution, porosity and specific surface area. Bulk density and encapsulation efficiency decreased. The release profile was characterized by a high initial burst due to the highly porous structure. Addition of salt to the external or continuous water phase (W2), however, stabilized the encapsulation process and, therefore, resulted in improved microsphere characteristics as a dense morphology, a reduced initial burst release, a drastically increased bulk density and encapsulation efficiency. Analysis of the specific surface area (BET) showed that the addition of salt to W2, regardless of the salt concentration in the W1 phase, decreased the surface area of the microspheres approximately 23-fold. Microsphere properties were influenced by salts additions through the osmotic pressure gradients between the two aqueous phases and the water flux during microsphere formation. Release profiles and encapsulation efficiencies correlated well with the porosity and the surface area of microspheres. Furthermore, the influence of a low molecular weight drug and different time-points of salt addition to W2 on microsphere characteristics were studied by encapsulation of acid orange 63 (AO63), confirming the results obtained with BSA. This study suggests that modification of the external water phase by adding salts is a simple and efficient method to encapsulate stabilized protein solution, with high encapsulation efficiency and good microsphere characteristics.

Animals↗
PubMedDate not supplied

Poly (D,L-lactide-co-glycolide) microspheres for long-term intravitreal delivery of aciclovir: influence of fatty and non-fatty additives.

Aciclovir (acicloguanosine) has been demonstrated to be effective in the treatment of intraocular pathologies such as herpes simplex virus retinitis and acute retinal necrosis. Although intravitreal injections have been used with fewer side-effects than intravenous administration, the risk of complications increases with the frequency of intravitreous injections. For this reason, a biodegradable drug-delivery system, such as microspheres, able to promote prolonged release of the drug, offers a good alternative to multiple intraocular administrations. In this work, aciclovir-containing poly (D,L-lactide-co-glycolide) microspheres were prepared by the solvent evaporation method. Seven additives were incorporated in the microspheres to modulate the in vitro release rate of the drug: four non-fatty substances (polyethylene glycol 300, polyethylene glycol 1500, hydroxypropyl methylcellulose and gelatin) and three fatty substances (isopropyl myristate, vitamin E and Labrafil M 1944 CS). Morphology of microspheres was evaluated by scanning electron microscopy. Granulometric analysis showed that particle size distribution was significantly influenced by the incorporation of additives. Loading efficiency decreased when fatty substances were added, whereas non-fatty additives promoted higher incorporation of the drug. Infrared and differential scanning calorimetry analyses indicated that microspheres prepared by the solvent evaporation process were not influenced by the type of additive used. In all cases, the initial burst resulted less than 5%. Additive-free microspheres showed a slow release within the first days, but when additives were incorporated, in general, the release rates of the drug were increased. Best release results were obtained for gelatin-containing microspheres. The release of aciclovir from these microspheres was adjusted to a zero-order kinetic from 1 to 49 days with a release constant of 1.13 microg/day/mg microspheres. A dose of 0.74 mg microspheres would be therapeutic for the herpes simplex and Epstein-Barr viruses (MIC 0.1 microg/ml) and 7.4 mg for varicella zoster virus (MIC 1 microg/ml) treatment in an animal model.

Acyclovir↗
PubMed2003

The effects of silicone fluid additives and silicone elastomer matrices on barnacle adhesion strength.

Barnacle adhesion strength was used to screen seventy-seven polydimethylsiloxane elastomeric coatings for fouling-release properties. The test coatings were designed to investigate the effect on barnacle adhesion strength of silicone fluid additive type, additive location, additive molecular weight, additive loading level, mixtures of additives, coating matrix type and coating fillers. The type of silicone fluid additive was the primary controlling factor in barnacle fouling-release. The type of silicone matrix in which the fluid resided was found to alter the effect on fouling-release. Two PDMS fluids, DMSC15 and DBE224, significantly reduced the adhesion strength of barnacles compared to unmodified elastomers. Optimum fouling-release performance was dependent on the interaction of fluid type and elastomeric matrix.

Adhesiveness↗
PubMed1997

HIV antibody testing: Genito-Urinary Clinic or additional site same-day testing service.

It has been suggested that different groups of individuals, possibly those at greater risk, may choose to attend anonymous HIV services not attached to Genito-Urinary Medicine Clinics. This paper reports the results of a comparative study of documented sociodemographic profile and risk category for individuals having HIV antibody tests at a Genito-Urinary Medicine Clinic and at an additional site same-day HIV antibody testing service not attached to a Genito-Urinary Medicine Clinic but within the same hospital. A retrospective case record analysis for 12 months from 1.10.93 to 30.9.94 was performed. During the 12-month study period 954 people had HIV testing at the additional site HIV antibody testing service and 803 had HIV antibody testing at the Genito-Urinary Medicine Clinic. Of those attending the additional site testing service 218 (22.9%) were homosexual/bisexual males as compared with 128 (15.9%) of the Genito-Urinary Medicine Clinic attendees (p < 0.01). A total of 22 (2.3%) of the individuals attending the additional site service gave a history of sexual contact in Africa as compared with 52 (65%) attending the Genito-Urinary Medicine Clinic (p < 0.001). There was no significant difference in the gender or age of those having HIV antibody tests at the two locations (p = 0.82 and p = 0.39 respectively). Four hundred and seventeen (52%) of the tests performed at the Genito-Urinary Medicine Clinic were performed on those who had not already decided to have a test before attending the clinic. Of those individuals who had decided to have a test before attending, 2.5 times as many attended the Same-Day Service as attended the Genito-Urinary Medicine Clinic (954 additional site attenders compared with 384 Genito-Urinary Medicine Clinic attenders). The results suggest that to optimize patient choice and benefit from a HIV antibody testing service this should be available at both Genito-Urinary Medicine Clinics and at additional site testing services.

Adult↗
PubMed2002

Full-scale evaluation of a multi-component additive for efficient control of activated sludge filamentous bulking.

A multi-component additive formulated for a more efficient control of activated sludge filamentous bulking was evaluated at a full-scale treatment plant experiencing 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, contrary to ordinary additives, this novel additive yielded immediate as well as long-term improvements in sludge sedimentation upon a few additions. Preliminary lab-scale toxicity tests showed that the treatment of the sludge by the additive should not impart any toxicity to the resulting effluent.

Animals↗
PubMed1978

H-2-restricted cytotoxic effectors generated in vitro by the addition of trinitrophenyl-conjugated soluble proteins.

Murine spleen cells from normal donors were cultured in vitro with trinitrobenzene sulfonate (TNBS)-conjugated soluble proteins, i.e., bovine gamma globulin (TNP-BGG) or bovine serum albumin (TNP-BSA). Addition of 100 mug of any of these TNP-proteins to the spleen cell cultures led to the generation of cytotoxic T-cell effectors which were H-2-restricted and TNP- specific. The lytic potential of such effectors was comparable to that generated by sensitization with TNBS-modified syngeneic cells, and was restricted to haplotypes shared at the K or K plus I-A, or the D regions of the H-2 complex. Greater effecter cell activity was generated by addition of TNP-BGG against TNBS-modified targets which shared K plus I-A than against modified targets which shared the D region with the responding cells, which suggests that the same immune response genes are involved when the response is generated by the addition of TNP-conjugated soluble proteins or of TNBS- modified cells. H-2-restricted, TNP-specific effecter cells were generated by culturing mouse spleen cells with syngeneic cells which had been preincubated with TNP- BGG or TNP-BSA for 1.5 h. The addition of unconjugated soluble proteins to the cultures did not result in cytotoxic effectors detectable on H-2-matched targets, whether the targets were prepared by modification with TNBS, or by incubation with either the unconjugated or TNP-conjugated proteins. Depletion of phagocytic cells in the tumor preparation by Sephadex G-10 column fractionation before incubation with TNP-BSA had no effect on their lysis by the relevant effector cells. Immunofluorescent staining of tumor target cells with anti-TNP antibodies indicated that TNP could be detected on the tumor cells within 10 rain of incubation with TNP-BSA. The cytotoxic response generated by addition of the TNP-proteins to spleen cell cultures was found to be T-cell dependent at the effector phase, as shown by the sensitivity of the lytic phase to absorbed RAMB and complement. Furthermore, the response did not appear to be attributable to antibody-dependent cellular cytotoxicity. Three mechanisms were considered which could account for the generation of H-2-restricted, TNP-specific, cytotoxic T-cell effectors by the addition of soluble TNP-proteins. These include covalent linkage of activated TNP groups from the soluble proteins to cell surface components, macrophage processing of the soluble conjugates and presentation to the responding lymphocytes in association with H-2-coded self structures, or hydrophobic interaction of the TNP-proteins to cell surfaces. Results obtained from sodium dodecyl sulfate gel patterns indicating that cell-bound TNP was still linked to BSA, and the observation that phagocytic-depleted cells could interact with the soluble TNP-proteins and function as H-2-restricted targets, appear not to favor the first two proposed mechanisms.

Animals↗
PubMed1999

Chloroquine exerts an additive in vitro anti-HIV type 1 effect when associated with didanosine and hydroxyurea.

Several groups, including ours, have reported that chloroquine (CQ) or its analog hydroxychloroquine has anti-HIV-1 activity both in vitro and in vivo. We studied in vitro whether the addition of CQ to the combination of hydroxyurea (HU) plus didanosine (ddI) had an additive effect in inhibiting the replication of HIV-1. Therefore both the H-9 T lymphocytic cell line and the U-937 promonocytic cell line as well as primary T cells and monocytes were infected with HIV-1 and then treated with HU at 0.2 mM and ddI at 1 microM and varying concentrations of CQ. Addition of CQ resulted in an additional inhibition of HIV-1 replication, as assessed by reverse transcriptase (RT) activity, with a CQ EC50 of 0.4-0.9 microM for the cell lines and of 0.2-0.9 microM for the primary cells. Similarly, addition of CQ further inhibited HIV-1 replication in U-1 cells stimulated either with LPS or H2O2 and in ACH-2 cells stimulated either with PMA or H2O2, with CQ EC50 values of 0.1 and 1 microM, respectively. Under the experimental conditions used, CQ induced neither toxicity nor apoptosis in the H-9 and U-937 cells. This in vitro additive anti-HIV-1 activity of CQ, in combination with HU + ddI, supports the idea that this triple regimen should be studied in clinical trials. It may become of particular interest to HIV-1-infected individuals from the developing world, in view of the low cost of both CQ and HU.

Anti-HIV Agents↗
PubMed1998

CCA addition by tRNA nucleotidyltransferase: polymerization without translocation?

The CCA-adding enzyme repairs the 3'-terminal CCA sequence of all tRNAs. To determine how the enzyme recognizes tRNA, we probed critical contacts between tRNA substrates and the archaeal Sulfolobus shibatae class I and the eubacterial Escherichia coli class II CCA-adding enzymes. Both CTP addition to tRNA-C and ATP addition to tRNA-CC were dramatically inhibited by alkylation of the same tRNA phosphates in the acceptor stem and TPsiC stem-loop. Both enzymes also protected the same tRNA phosphates in tRNA-C and tRNA-CC. Thus the tRNA substrate must remain fixed on the enzyme surface during CA addition. Indeed, tRNA-C cross-linked to the S. shibatae enzyme remains fully active for addition of CTP and ATP. We propose that the growing 3'-terminus of the tRNA progressively refolds to allow the solitary active site to reuse a single CTP binding site. The ATP binding site would then be created collaboratively by the refolded CC terminus and the enzyme, and nucleotide addition would cease when the nucleotide binding pocket is full. The template for CCA addition would be a dynamic ribonucleoprotein structure.

Base Sequence↗
PubMedDate not supplied

Winston's "No Additives" campaign: "straight up"? "no bull"?

OBJECTIVE: The author used data from a larger study to examine adolescents' and adults' responses to Winston cigarettes' "No Additives" advertising campaign. METHODS: The author analyzed responses from 400 adolescents ages 12-17 and 203 adults ages 30-50 who were asked what they believed the meaning of the "No Additives" slogan to be. The author also analyzed adolescents' responses to questions about four specific Winston "No Additives" ads. RESULTS: Two-thirds of adolescents and 27% of adults believed that "No Additives" meant one or more of the following: that Winston cigarettes are healthier than other cigarettes, that they are less likely to harm health, or that they are less likely to be addictive. Adolescents perceived the models in three ads to be younger than 25 years old. Among adolescent respondents, smokers were more likely than nonsmokers to like the ads and to believe the ads made smoking more appealing. CONCLUSIONS: The "No Additives" slogan was perceived by a majority of adolescents and about a quarter of adults as implying one or more health claims. The results of this analysis suggest that the Federal Trade Commission's action in requiring a disclaimer on the "No Additives" ads is well founded but the disclaimer should be strengthened.

Adolescent↗
PubMed2026

Genome assembly and subgenomic interactions in Brassica napus additional lines with an alien B05 chromosome from B. juncea.

Alien chromosome addition lines hold significant value for breeding and genetic research. However, the genetic interaction between the recipient genome(s) and the alien chromosomes remain largely unclear. Here, we analyzed the genomic composition and gene expression of two purple-leaved B. napus alien addition lines carrying chromosome B05 from B. juncea: the monosomic line ZYCB3 (MAAL, 2n = 39, AACC + 1B05) and the disomic line ZY52 (DAAL, 2n = 40, AACC + 2B05). We assembled a chromosome-level genome of the DAAL ZY52 disomic line and characterized its genomic variation and chromosome introgression patterns. In addition to chromosome B05, multiple introgressed fragments derived from the donor B. juncea line ZYJC were identified, revealing extensive genome remodeling during distant hybridization and backcross breeding. We then used multi-omics approaches to explore chromosomal interactions and the regulation of anthocyanin biosynthesis. Notably, the addition of chromosome B05 was associated with stronger repression of homoeologous genes on C-subgenome chromosomes than on A-subgenome chromosomes. In ZY52, homoeologous genes on chromosome C01 showed reduced expression, whereas in the ZYCB3 monosomic line reduced expression was observed on both C01 and C02. Comparative transcriptomic and metabolomic analyses further showed that highly expressed anthocyanin biosynthesis genes (ABGs) on chromosome B05contributed to anthocyanin accumulation and the purple-leaf phenotype in both addition lines. Overall, this study provides new insights into interchromosomal interactions, genome remodeling, and phenotypic variation in alien addition lines.

Journal Article↗
PubMed2001

Additivity and associative effects of metabolizable energy and amino acid digestibility in barley and canola meal for White Pekin ducks.

An experiment was conducted using the TMEn bioassay method to investigate the additivity and associative effects of metabolizable energy and amino acid digestibility in barley and canola meal for White Pekin ducks. Additivity was tested by comparing the difference between observed values determined in a complete diet and predicted values from measurements determined with individual ingredients (barley and canola meal). Six ducks each were assigned to diets of barley, canola meal, the complete diet, and dextrose. Dextrose-fed ducks were used for estimation of endogenous losses for calculation of true amino acid digestibility. The observed AME, TME, AMEn, and TMEn values in the complete diet were 0.065, 0.083, 0.016, and 0.023 (kcal/g), respectively, numerically higher than predicted values. Differences between observed and predicted values were not significant (P > 0.05), indicating that the AME, AMEn, TME, and TMEn in barley and canola meal were all additive. In general, observed values for apparent amino acid digestibility (AAAD) and true amino acid digestibility (TAAD) in the complete diet were higher than those predicted from individual ingredients. Observed AAAD for lysine, histidine, tryptophan, alanine, and aspartate were higher (P < 0.05) than predicted values, indicating that digestibilities of these amino acids were not additive. The mean of AAAD in canola meal (77.29%) was higher (P < 0.05) than the observed values of barley (52.2%) and complete diet (64.55%). For TAAD values, differences between observed and predicted values were significant for lysine, histidine, and tryptophan (P < 0.05). The mean of TAAD in canola meal, barley, and complete diet were 85.88, 80.87, and 81.33%, respectively. The average difference between observed and predicted values for TAAD (1.18 %) was smaller than that of AAAD (5.41%). These results indicated that ME values for barley and canola meal were additive in the complete diet but that digestibilities of some amino acids were not additive; they further suggested that there were some associative effects of amino acids in barley and canola meal for ducks.

Amino Acids↗
PubMed2003

Effect of enzyme addition on the digestibilities of cell wall polysaccharides and oligosaccharides from whole, dehulled, and ethanol-extracted white lupins in chickens.

Three experiments were conducted to examine the effects of a commercial enzyme preparation on chicks performance and digestibilities of nonstarch polysaccharides (NSP), raffinose (R), stachyose (S), and total oligosaccharides (O) in diets containing whole and dehulled lupin and ethanol-extracted dehulled lupin meal. Ethanol extract was also used to produce a rich oligosaccharide fraction. In the first experiment, the dehulling treatment and the addition of enzyme to the diet improved (P < 0.05) weight gain (24 and 15%), feed-to-gain ratio (13 and 9%), dry matter retention (32 and 8%), apparent protein digestibility (6 and 3%) and ileal digestibilities of raffinose (19 and 119%), stachyose (85 and 204%), and total oligosaccharides (68 and 178%), respectively. In addition, enzyme treatment improved (P < 0.05) excreta digestibility values for NSP (from -1.7 to 5.5%), R (from 64.6 to 92.6%), S (from 48.8 to 82.4%), and O (from 55.8 to 83.5%). In the second experiment, extraction of the ethanol soluble components from dehulled lupin decreased (P < 0.0001) weight gain (51%), and increased (P < 0.0001) feed consumption (34%), feed-to-gain ratio (32%), relative gizzard weight (14%), and the relative ceca length (20%). The addition of the isolated fraction of oligosacharides to the corn-extracted lupin diet (7.5 and 15%) yielded performance values similar to those obtained with the unextracted dehulled lupin. The addition of enzymes to the diets significantly improved the weight gain (11%) and feed to gain ratio (6%), and decreased relative gizzard weight (12%) and relative ceca length (7%). Ileal digestibilities of R, S, and O were considerably lower than corresponding excreta digestibilities. The excreta digestibility of NSP and excreta and ileal digestibilities of R, S, and O were lower (P < 0.05) in chicks fed the lupin diet containing the high concentration of extract compared with those fed the same diet containing the lower concentration of extract. Enzymes, when added to the diets, increased (P < 0.05) the digestibilities of R, S, and O with the relative effects being much greater for ileal than excreta samples. In the third experiment, the ethanol extract (7.5 and 15%) added to a corn-soybean diet improved weight gain, feed consumption, and feed-to-gain ratio by 19, 13, and 6%, respectively. Ileal digestibilities of R, S, and O were low (< 45%), especially in chicks fed the diets containing the high amount of added oligosaccharide fraction. There was no effect of enzyme addition on the performance parameters. However, supplemental dietary enzymes improved (P < 0.05) ileal and excreta digestibilities of oligosaccharides from 15.6 and 68.6% to 52.3 and 84.8%, respectively. In summary, dehulling greatly improved the nutritional value of lupin, while removal of the ethanol soluble materials, including raffinose and stachyose considerably decreased its value. The oligosaccharide fraction does not seem to have an antinutritive effect and the addition of enzymes increased the digestibilities of NSP, raffinose, and stachyose but did not significantly improve chick performance.

Animal Feed↗
PubMed2004

The effect of fat type, carbohydrase, and lipase addition on growth performance and nutrient utilization of young broilers fed wheat-based diets.

A 2 x 2 x 2 factorial experiment was conducted to evaluate the effects of fat type (beef tallow [50 g/kg diet] or canola oil [50 g/kg of diet]), carbohydrase addition (none or carbohydrases [0.4 g/kg diet]), and lipase addition (none or lipase [0.2 g/kg of diet]) on growth performance and nutrient utilization of male broilers fed a wheat-based diet from 5 to 18 d. The carbohydrase supplement contained xylanase, glucanase, cellulase, and other enzyme activities. The experimental diets were formulated to be suboptimal in major nutrients and each was fed in a mash form to 10 replicate pens of 5 broilers per pen. Body weight gain was not affected by fat type but a poorer feed/gain ratio (P < 0.001) was noted for tallow-containing diets. Regardless of fat type, carbohydrase enzyme supplementation improved (P < 0.001) BW gain and feed/gain ratio. There was no effect of lipase addition on chicken performance and nutrient utilization. When compared with canola oil, tallow-containing diets had a lower (P < 0.001) apparent fat digestibility and consequently a lower dietary AMEn content. Carbohydrase enzyme addition improved (P < 0.001) fat, starch, nitrogen, and nonstarch polysaccharide (NSP) digestibilities in the small intestine, improved AMEn, and reduced (P < 0.001) jejunal digesta viscosity in both fat types. Carbohydrase supplementation increased water-soluble (P < 0.001) and decreased water-insoluble (P < 0.001) NSP concentrations in the small intestine. The interaction between fat type and carbohydrase addition was only significant for fat digestibilities, with greater improvements seen for diets containing tallow. Significant interactions between carbohydrase addition and intestinal segment were noted for fat, starch, nitrogen, and NSP digestibilities, with the enzyme effects being greater in the jejunum than the ileum. It is evident from the present study that an appropriate carbohydrase preparation could eliminate the negative effects of soluble NSP on animal fat utilization in a wheat-based broiler diet.

Animal Nutritional Physiological Phenomena↗
PubMed2002

Valsartan therapy has additive anti-oxidative effect to that of fluvastatin therapy against low-density lipoprotein oxidation: studies in hypercholesterolemic and hypertensive patients.

In hypercholesterolemic and hypertensive patients, an increased propensity of their low-density lipoprotein (LDL) to oxidative modification has been observed. Because oxidized LDL (ox-LDL) plays a major role in atherosclerosis, the current study analyzed the anti-oxidative effect of valsartan (an angiotensin II receptor antagonist) therapy in combination with fluvastatin therapy in these patients. Administration of 40 mg/d of fluvastatin for 2 months to seven patients resulted in significant reduction in plasma total and LDL cholesterol (by 24-28%). Valsartan administration (80 mg/d for an additional 2-month period) in combination with fluvastatin did not further affect plasma cholesterol levels. Fluvastatin therapy inhibited the susceptibility of LDL to copper ion-induced oxidation, as shown by prolongation of the lag time by 22% and by a reduction of thiobarbituric acid-reactive substances (TBARS) levels by 14%, as compared with the patient's LDL baseline oxidation. The addition of valsartan to fluvastatin resulted in a further 17% prolongation of the lag time and in an additional reduction of 21% in TBARS levels. In a parallel study, the LDL from eight patients who were first treated with 80 mg/d of valsartan for 2 months demonstrated reduced susceptibility to copper ion-induced oxidation, as observed by prolongation of lag time by 23% and reduction in TBARS levels by 19%, compared with the baseline values. The administration of 40 mg/d of fluvastatin for an additional 2 months in combination with valsartan, however, demonstrated no further inhibitory effect on LDL oxidation. The anti-oxidative properties of fluvastatin and valsartan against LDL oxidation were also demonstrated in vitro and the combination of both drugs was shown to have an additive effect. Valsartan therapy in hypercholesterolemic and hypertensive patients has an additive anti-oxidative effect to that of fluvastatin therapy. This may be related both to the anti-oxidative properties of valsartan and to the blocking of angiotensin II-induced oxidative stress.

Analysis of Variance↗