Development of an in vitro macrophage screening system on the immunomodulating effects of feed components.

BACKGROUND: While feed components capable of modulating the immune system are highly sought after and marketed, often little evidence is available to support functional immune response claims. Thus, a high-throughput in vitro cell screening system was developed to test these compounds for innate immune signaling effects, using Saccharomyces cerevisiae and its cell wall components in addition to lauric acid and its esters as models in two separate experiments. This screening system utilized RAW 264.7 murine macrophages to assess live S. cerevisiae cells and S. cerevisiae-derived cell wall components ß-glucan, mannan, and zymosan (a crude cell wall preparation containing both ß-glucan and mannan). D-mannose was also evaluated as the monomer of mannan. We also examined the effect of a saturated fatty acid (C12:0, lauric acid) and its esters (methyl laurate and glycerol monolaurate) on innate immune cell activation and cellular metabolism. RAW cells were transfected with a vector that drives expression of alkaline phosphatase upon promoter activation of nuclear factor κ-light-chain-enhancer of activated B cells (NFκB), a major inflammatory/immune transcription factor. RAW cells were incubated with 0.01, 0.1 or 1 mg/mL of yeast compounds alone or RAW cells were challenged with LPS and then incubated with yeast compounds. In a separate experiment, RAW cells were incubated with 0, 0.5, 2.5, 12.5, 62.5, and 312.5 µmol/L of lauric acid, methyl laurate, or glycerol monolaurate alone, or RAW cells were challenged with LPS and then incubated with fatty acid treatments. RESULTS: Treatment with zymosan or ß-glucan alone induced NFκB activation in a dose-dependent manner, whereas treatment with D-mannose, mannan, or live S. cerevisiae cells did not. Post-treatment with mannan after an LPS challenge decreased NFκB activation, suggesting that this treatment may ameliorate LPS-induced inflammation. Slight increases in NFκB activation were found when fatty acid treatments were applied in the absence of LPS, yet substantial reductions in NFκB activation were seen when treatments were applied following an LPS challenge. CONCLUSIONS: Overall, this cell screening system using RAW macrophages was effective, high-throughput, and sensitive to feed components combined with LPS challenges, indicating modulation of innate immune signaling in vitro.

Impact of Software Modeling on the Accuracy of Perfusion MRI in Glioma.

BACKGROUND AND PURPOSE: Relative cerebral blood volume, as measured by T2*-weighted dynamic susceptibility-weighted contrast-enhanced MRI, represents the most robust and widely used perfusion MR imaging metric in neuro-oncology. Our aim was to determine whether differences in modeling implementation will impact the correction of leakage effects (from blood-brain barrier disruption) and the accuracy of relative CBV calculations as measured on T2*-weighted dynamic susceptibility-weighted contrast-enhanced MR imaging at 3T field strength. MATERIALS AND METHODS: This study included 52 patients with glioma undergoing DSC MR imaging. Thirty-six patients underwent both non-preload dose- and preload dose-corrected DSC acquisitions, with 16 patients undergoing preload dose-corrected acquisitions only. For each acquisition, we generated 2 sets of relative CBV metrics by using 2 separate, widely published, FDA-approved commercial software packages: IB Neuro and nordicICE. We calculated 4 relative CBV metrics within tumor volumes: mean relative CBV, mode relative CBV, percentage of voxels with relative CBV > 1.75, and percentage of voxels with relative CBV > 1.0 (fractional tumor burden). We determined Pearson (r) and Spearman (ρ) correlations between non-preload dose- and preload dose-corrected metrics. In a subset of patients with recurrent glioblastoma (n = 25), we determined receiver operating characteristic area under the curve for fractional tumor burden accuracy to predict the tissue diagnosis of tumor recurrence versus posttreatment effect. We also determined correlations between rCBV and microvessel area from stereotactic biopsies (n = 29) in 12 patients. RESULTS: With IB Neuro, relative CBV metrics correlated highly between non-preload dose- and preload dose-corrected conditions for fractional tumor burden (r = 0.96, ρ = 0.94), percentage > 1.75 (r = 0.93, ρ = 0.91), mean (r = 0.87, ρ = 0.86), and mode (r = 0.78, ρ = 0.76). These correlations dropped substantially with nordicICE. With fractional tumor burden, IB Neuro was more accurate than nordicICE in diagnosing tumor versus posttreatment effect (area under the curve = 0.85 versus 0.67) (P < .01). The highest relative CBV-microvessel area correlations required preload dose and IB Neuro (r = 0.64, ρ = 0.58, P = .001). CONCLUSIONS: Different implementations of perfusion MR imaging software modeling can impact the accuracy of leakage correction, relative CBV calculation, and correlations with histologic benchmarks.

Yeast product supplementation modulated humoral and mucosal immunity and uterine inflammatory signals in transition dairy cows.

The transition from late gestation to early lactation is characterized by substantial metabolic stress and altered immune function. The objective of this study was to assess the effects of supplementing a yeast product derived from Saccharomyces cerevisiae on immunity and uterine inflammation in transition cows. Forty multiparous Holstein cows were blocked by expected parturition date and randomly assigned within block to 1 of 4 treatments (n=10) from 21d before expected parturition to 42d postpartum. Rations were top-dressed with a product containing yeast culture plus enzymatically hydrolyzed yeast (YC-EHY; Celmanax, Vi-COR, Mason City, IA) at the rate of 0, 30, 60, or 90g/d throughout the experiment. Cows were injected subcutaneously with ovalbumin on d -21, -7, and 14 to assess their humoral response. Data were analyzed using mixed models with repeated measures over time. Concentrations of colostrum IgG were unaffected by treatments. A treatment × week interaction was observed for somatic cell linear score, reflecting a tendency for a quadratic dose effect on wk 1 (2.34, 2.85, 1.47, and 4.06±0.59 for 0, 30, 60, and 90g/d, respectively) and a quadratic dose effect on wk 5 (1.36, -0.15, -1.07, and 0.35±0.64 for 0, 30, 60, and 90g/d, respectively). Platelet count was increased by YC-EHY. Increasing YC-EHY dose linearly increased plasma anti-ovalbumin IgG levels following 3 ovalbumin challenges, suggesting that treatments enhanced humoral immunity. Increasing YC-EHY dose also quadratically increased fecal IgA concentrations in early lactation, suggesting that 30 and 60g/d doses enhanced mucosal immunity. Uterine neutrophil populations were much greater in samples collected on d 7 compared with those on d 42 (32.1 vs. 7.6±3.5% of cells), reflecting neutrophil infiltration immediately after calving, but no treatment effect was detected. Significant day effects were detected for mRNA of IL-6, IL-8, neutrophil myeloperoxidase (MPO), and neutrophil elastase (ELANE) in the uterine samples, reflecting greater abundance of these transcripts collected on d 7 compared with d 42. A quadratic dose effect was detected for IL-6, indicating that 30 and 60g/d doses decreased uterine IL-6 mRNA. The mRNA abundance of MPO and ELANE was increased linearly by YC-EHY. Supplementation with YC-EHY enhanced measures of humoral and mucosal immunity and modulated uterine inflammatory signals and mammary gland health in transition dairy cows.

Yeast product supplementation modulated feeding behavior and metabolism in transition dairy cows.

Yeast supplementation has been shown to increase feed intake and production in some studies with early lactation dairy cows, but the mechanisms underlying such an effect remain unknown. The objective of this study was to assess the effects of supplementing a yeast product derived from Saccharomyces cerevisiae on production, feeding behavior, and metabolism in cows during the transition to lactation. Forty multiparous Holstein cows were blocked by expected calving date and randomly assigned within block to 1 of 4 treatments (n=10) from 21 d before expected calving to 42 d postpartum. Rations were top-dressed with a yeast culture plus enzymatically hydrolyzed yeast (YC-EHY; Celmanax, Vi-COR Inc., Mason City, IA) at the rate of 0, 30, 60, or 90g/d throughout the experiment. Dry matter and water intake, feeding behavior, and milk production were monitored. Plasma samples collected on -21, -7, 1, 4, 7, 14, 21, and 35 d relative to calving were analyzed for glucose, ß-hydroxybutyrate, and nonesterified fatty acids. Data were analyzed using mixed models with repeated measures over time. Pre- or postpartum dry matter intake and water intake did not differ among treatments. Quadratic dose effects were observed for prepartum feeding behavior, reflecting decreased meal size, meal length, and intermeal interval, and increased meal frequency for cows received 30 and 60g/d of YC-EHY. Postpartum feeding behavior was unaffected by treatments. Milk yields were not affected (45.3, 42.6, 47.8, and 46.7kg/d for 0, 30, 60, and 90g/d, respectively) by treatments. Tendencies for increased percentages of milk fat, protein, and lactose were detected for cows receiving YC-EHY. Supplementing YC-EHY increased plasma ß-hydroxybutyrate and tended to decrease (quadratic dose effect) glucose but did not affect nonesterified fatty acids. Yeast product supplementation during the transition period did not affect milk production and dry matter intake but modulated feeding behavior and metabolism.

Resin to metal bond strengths using two commercial systems.

STATEMENT OF PROBLEM: A secure bond between resin and an alloy framework is necessary for clinical success in removable prosthodontics. PURPOSE: This study compared the shear bond strength of composite to composite to metal with two commercially available chemical bonding systems: a silicoating system (Silicoater) and a nitrogenous heterocycle-acrylonitrile system (Kevloc). MATERIAL AND METHODS: Fifty-two nickel-chromium cubes were cast and composite resin was bonded to the alloy surfaces according to manufacturer's directions. After storage at 35 degrees C for 15 days, and thermocycling at 5 degrees C and 55 degrees C for 1200 cycles, the bonds were fractured in shear on a universal testing machine. RESULTS: Mean bond strength for the silicoated sample was 10.93 MPa and for the heterocycle-acrylnitrate system 11.44 MPa. An unpaired t test revealed no difference between the groups (p = 0.60). Visual inspection of the fracture surfaces revealed that failure was adhesive at the resin-to-metal surface in almost all the specimens.

Maxillary sinus morphology in differential dental diagnosis.

In this case, the shape of the maxillary sinus was misinterpreted as a periapical pathological condition. Based on this anatomic misinterpretation, conventional endodontic therapy had been performed on two teeth. When the suspected lesion did not resolve, an exploratory procedure revealed the unusual morphology of an otherwise normal maxillary sinus. The anatomy and morphology of the maxillary sinus in differential dental diagnosis are discussed, and surgical exploration is demonstrated. A case of healthy sinus anatomy with abnormal morphology is reported.

Reduction of fertility and alteration of uterine pH in heifers fed excess ruminally degradable protein.

The objective of these studies was to elucidate the causes underlying the reduction of fertility associated with feeding of excess ruminally degradable protein to cattle. Holstein heifers were fed total mixed rations that either met (Normal) or exceeded (High) ruminally degradable protein requirements. In Exp. 1 heifers (n = 80) were inseminated at estrus after being fed the experimental diets for 4 wk. First-service conception rates were 82 and 61% for the Normal and High groups, respectively (P < .05). Plasma urea nitrogen (PUN) levels were elevated (10.2 +/- .17 vs 14.8 +/- .19 mg/dL) in the High group throughout the experiment (P < .05). In Exp. 2, heifers (n = 32) receiving the same diets as in Exp. 1 were fitted with catheters in a jugular vein, in the bladder, and in the uterus on either the day before expected estrus or d 6 after estrus. On estrus or d 7, plasma and urinary NH4 and urea nitrogen and uterine pH were determined at 4-h intervals for 24 h beginning just before feeding. Plasma NH4 was variable and did not differ between treatments or days of the estrous cycle. During the 24-h period, urinary urea nitrogen and PUN were elevated (P < .05) in the High groups and did not differ between days of the cycle. Urinary NH4 excretion was elevated (P < .05) during the 24-h period only in the High group on d 7. Uterine pH did not change over time after feeding.(ABSTRACT TRUNCATED AT 250 WORDS)

Alterations of pH in response to increased dietary protein in cattle are unique to the uterus.

This study was undertaken with two objectives: 1) to determine whether the effect of excess dietary protein on intrauterine pH in cattle is specific to the uterus or manifested in other bodily fluids and 2) to determine whether the effect of excess ruminally degradable protein on uterine pH can be ameliorated by substitution with a less-degradable protein source. Thirty-six Holstein cows in early lactation were fed isoenergetic total mixed rations that either 1) met undegradable intake protein (UIP) and degradable intake protein (DIP) requirements (Balanced), 2) met DIP requirements and exceeded UIP requirements by 25% (High UIP), or 3) met UIP requirements and exceeded DIP requirements by 25% (High DIP). After diets had been fed > or = 2 wk, uterine, blood, salivary, and urinary pH and plasma urea nitrogen were determined at estrus (d 0) and d 7. Plasma urea nitrogen (mg/dL) was not different between estrus and d 7 but was significantly affected by diet (Balanced, 16.1 +/- 2.3; High UIP, 19.2 +/- 1.6; High DIP, 22.3 +/- 2.6; P < .05). There was no effect of treatment on the pH of any fluid measured at estrus: intrauterine, blood, salivary, and urinary pH averaged 6.84 +/- .05, 7.39 +/- .01, 8.30 +/- .05, and 8.15 +/- .05, respectively. In contrast, on d 7, uterine pH was significantly lower in both high-protein groups, regardless of protein degradability (Balanced, 7.13 +/- .05; UIP, 6.95 +/- .04; DIP, 6.85 +/- .05; P < .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Platelet activating factor activity in the phospholipids of bovine spermatozoa.

Platelet activating factor (PAF) has been detected in sperm from several mammalian species and can affect sperm motility and fertilization. Because bovine sperm contain a high percentage of ether-linked phospholipid precursors required for PAF synthesis, a study was undertaken to determine the PAF activity of bovine sperm phospholipids. Total lipids of washed, ejaculated bull sperm were extracted, and phospholipids were fractionated by thin-layer chromatography. Individual phospholipid fractions were assayed for PAF activity on the basis of [3H]serotonin release from equine platelets. PAF activity was detected in the PAF fraction (1.84 pmol/mumol total phospholipid) and in serine/inositol (PS/PI), choline (CP), and ethanolamine phosphoglyceride (EP) and cardiolipin (CA) fractions. Activity was highest in the CP fraction (8.05 pmol/mumol total phospholipid). Incomplete resolution of PAF and neutral lipids may have contributed to the activity in the PS/PI and CA fractions, respectively. Phospholipids from nonsperm sources did not stimulate serotonin release. Platelet activation by purified PAF and by sperm phospholipid fractions was inhibited by the receptor antagonist SRI 63-675. These results indicate that bovine sperm contain PAF and that other sperm phospholipids, especially CP and EP, which are high in glycerylether components, are capable of receptor-mediated platelet activation.

Evaluation of Abbott CMV-M enzyme immunoassay for detection of cytomegalovirus immunoglobulin M antibody.

The Abbott CMV-M enzyme immunoassay (EIA) for the qualitative determination of immunoglobulin M (IgM) antibody to cytomegalovirus in human serum was compared with the indirect fluorescent-antibody (IFA) test on 338 human serum specimens. Discordant specimens were evaluated by IFA following isolation of IgM fractions. Discordant specimens remaining after IFA testing were evaluated by an IgM-specific EIA (CYTOMEGELISA M; M.A. Bioproducts). After resolution of discordant specimens, the CMV-M EIA was 94.7% sensitive and 99.1% specific.

Immunoglobulin M antibodies detected by enzyme-linked immunosorbent assay and radioimmunoassay in the diagnosis of cytomegalovirus infections in pregnant women and newborn infants.

Immunoglobulin M (IgM) antibodies were detected by a commercially available enzyme-Linked Immunosorbent Assay (ELISA) in 36 of 49 (73%) pregnant women with primary cytomegalovirus (CMV) infection. A positive ELISA-IgM result occurred in 10 of 13 patients (77%) assessed within 8 weeks of seroconversion. The sensitivity of the radioimmunoassay (RIA) to identify primary infection in pregnant women was comparable, 78% in general and 86% for women tested within 16 weeks of seroconversion. Of the 36 women with primary infection who had detectable IgM antibodies by ELISA, 25 (69%) were delivered of congenitally infected infants, whereas of the 13 with undetectable IgM antibodies, 7 (54%) transmitted the infection in utero. IgM antibodies were detected by ELISA in only 5 of 43 (11%) women who experienced a recurrence of CMV which either did or did not result in congenital infection. RIA was less likely to measure CMV-specific IgM in recurrent infection, inasmuch as 1 of 19 (5.2%) women with proven recurrent infection had detectable IgM antibody, giving RIA a better specificity for primary infection. Specific IgM antibodies were detected by ELISA in 42 of 61 (69%) babies congenitally infected with CMV and in 4 of 70 (5.7%) uninfected control newborn infants. The RIA was superior for diagnosis of congenital CMV infection, with a sensitivity of 89% and a specificity of 100%. The lower sensitivity of the ELISA-IgM occurred in the category of congenitally infected infants born to mothers with recurrent infection (43%), a group that is at the lowest risk of disease or to develop sequelae. This commercially available ELISA-IgM could be used in combination with a CMV-specific IgG test for monitoring women during pregnancy for primary infection.