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Objectives: The objective of this study was to evaluate health outcomes for workers subject to piece rate historically to better understand the implications of pay type in the modern-day gig economy. While piece rate occurring in the 1980s and 1990s predates recent platform-based employment, it introduced and normalized patterns of economic precariousness that are instrumental in the current gig economy. Evidence suggests that such pay types may result in poor health outcomes; however, cross-sector evidence of its long-term effects on US workers is lacking. This article represents the first longitudinal cross-sector analysis relating health outcomes to this performance pay type in US workers., Study Design: This is a longitudinal cohort study., Methods: Data from six survey waves of the 1979 National Longitudinal Survey of Youth collected between 1988 and 2000 are used in a random-effects logit model to predict self-reported health limitations related to piece rate, while controlling for worker, work environment, lifestyle, time, and location trends., Results: Pay tied to piece rate in current or prior periods significantly increases the odds of self-reported health limitations compared with salaried work (odds ratio [OR]: 1.4-1.8). These effects are elevated for the subgroups of low-wage (OR: 1.5-1.8), female (OR: 1.8-1.9), and non-white (OR: 2.0-2.1) workers compared with their high-wage, male, and white peers., Conclusions: The results suggest that piece rate pay designed to promote efficiency may have important negative implications for worker health, especially for the most vulnerable members of the US workforce such as women, minority, and low-income workers. Given the growing popularity of performance-based pay to the gig economy, more research is needed to determine if the practice is justified from a public health perspective., (Copyright © 2019 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Data were collected from 1953 through 1980 from identical and fraternal twin beef and dairy females born in 1953, 1954, 1959, 1964, and 1969, from crossbred females born as singles in 1974, and their progeny. Numbers of dams that weaned at least one calf and were included in the first analysis were 37, 45, and 56 in the 1964, 1969, and 1974 data sets, respectively. Respective numbers of dams that weaned three calves and were included in a second analysis were 6, 8, 8, 22, 33, and 33 in the 1953, 1954, 1959, 1964, 1969, and 1974 experiments. Individual feed consumption was measured at 28-d intervals from the time females were placed on the experiment at 240 d of age until three calves were weaned or the dams had reached 5 yr of age. Residual feed intake (RFI) and residual BW gain (RG) of heifers that subsequently became dams were determined based on ADG and DMI from 240 d of age to first calving. Various measures of cow efficiency were calculated on either a life cycle or actual lifetime basis using ratios of progeny and dam weight outputs to progeny and dam feed inputs. The correlation between RFI and DMI was large and positive (r = 0.67; P < 0.0001), and RG was highly correlated with ADG (r = 0.75; P < 0.0001). Correlations of RFI with cow efficiency ratios that included harvest weight, carcass weight, or weight of trimmed wholesale cuts as measures of output ranged from -0.05 (P > 0.10) to -0.17 (P < 0.10), indicating that heifers with better (i.e., more negative) RFI values tended to become slightly more efficient cows. Correlations of RG with life cycle and actual lifetime cow efficiency ratios ranged from 0.08 (P > 0.10) to 0.23 (P < 0.05), demonstrating that heifers with better (i.e., more positive) values for RG were somewhat more efficient as cows. The correlations were stronger when cow salvage value was included in the measures of cow efficiency. Correlations of DMI and mid-test metabolic BW (MMW) with life cycle cow efficiency ratios that did not include cow salvage value as output ranged from -0.15 (P < 0.10) to -0.22 (P < 0.01). Correlations of DMI and MMW with actual lifetime cow efficiency ratios varied from -0.20 (P < 0.05) to -0.36 (P < 0.001). Therefore, smaller heifers that consumed less feed had superior cow efficiency ratios. Correlations of RFI with carcass grade, backfat thickness, marbling score, and kidney fat of progeny indicated that heifers with superior RFI would tend to produce leaner offspring.

Data were collected from 1953 through 1980 from identical and fraternal twin beef and dairy females born in 1953, 1954, 1959, 1964, and 1969, and from crossbred females born as singles in 1974, and their progeny. Numbers of dams that weaned at least 1 calf and were included in the first analysis were 37, 45, and 56 in the 1964, 1969, and 1974 data sets, respectively. Respective numbers of dams that weaned 3 calves and were included in a second analysis were 6, 8, 8, 22, 33, and 33 in the 1953, 1954, 1959, 1964, 1969, and 1974 experiments. Individual feed consumption was measured at 28-d intervals from the time females were placed on the experiment until 3 calves were weaned or the dams had reached 5 yr of age. Residual feed intake (RFI) and residual gain (RG) of the heifers that subsequently became the dams in this study were determined based on ADG and DMI from 240 d of age to first calving. Various measures of cow efficiency were calculated on either a life cycle or actual lifetime basis using ratios of progeny and dam weight outputs to progeny and dam feed inputs. Residual feed intake was phenotypically independent of ADG and metabolic midweight (MMW), whereas the correlation between RFI and DMI was positive and highly significant ( = 0.67; < 0.0001). Residual gain was highly correlated with ADG ( = 0.75; < 0.0001) and had near 0 correlations with DMI and MMW. Correlations indicated that heifers that ate less and had smaller metabolic midweights from 240 d of age to first calving had superior efficiency ratios as cows. Residual feed intake was not significantly correlated with age at puberty, age at calving, or milk production. Results of this study do not indicate any serious antagonisms of postweaning heifer RFI with subsequent cow and progeny performance traits or with life cycle or actual lifetime cow efficiency. In addition, selection for increased RG would result in earlier ages at calving, but would also tend to result in taller and heavier cows.

Hyperplastic growth and hypertrophic growth within adipose tissue is tightly associated with cell cycle activity. In this study, CCNG2 and CDKN2C were found to be correlated with cell cycle inhibition during fat cell differentiation, whereas CCND3, CCNA1, and ANAPC5 were positively associated with cell cycle activity during fat cell proliferation after selection based on GEO datasets available on the NCBI website. The findings were validated through comparison of expressions of these genes among different tissues/fractions in broiler chickens and time points during primary cell culture using quantitative real-time PCR. Development of broiler subcutaneous adipose tissue was investigated on embryonic days 15 and 17 and on post-hatch days 0, 5, 11, and 33 using H&E staining and PCNA immunostaining with DAPI counter stain. In addition, mRNA expressions of five cell cycle regulators as well as precursor cell and adipocyte markers were measured at those time points. The results suggest that cellular proliferation activity decreased as the fat pad grows, but a population of precursor cells seemed to be maintained until post-hatch day 5 despite increasing differentiation activity. Hypertrophic growth gradually intensified despite a slight cessation on post-hatch day 0 due to increased energy expenditure during hatching and delayed food access. From post-hatch day 5 to day 11, most of the precursor cells may become differentiated. After post-hatch day 11, hyperplastic growth seemed to slow, while hypertrophic growth may become dominant. This study provides further understanding about broiler fat tissue development which is imperative for effective control of fat deposition.

In this study, we investigated the associations between genetic variants in the promoter region of the insulin-like growth factor-1 (IGF1) gene and blood serum IGF1 concentration in Hanwoo cattle. Polymerase chain reaction primers were based on GenBank accession No. AF404761 and amplified approximately 533-bp segments. Newly identified sequences were submitted to GenBank (accession No. DQ267493). Sequence analysis revealed that genetic variants were located at a nucleotide position 323 for the nucleotide substitution C/A that was first reported in this study and positions 326-349 for a repeat motif (CA10-11). The allele frequencies of g.323C>A were 0.264 (C) and 0.736 (A) without significant deviation from Hardy-Weinberg equilibrium. Frequencies of the repeat motif CA(10) and CA(11) were 0.604 and 0.396, respectively. Statistical analysis revealed that the genetic variation g.323C>A was significantly associated with blood serum IGF1 concentrations with significant additive genetic effects, whereas no associations were found for the repeat motif. IGF1 concentrations were positively (r = 0.453) and negatively (r = -0.445) correlated with weights in the growing stages (16-21 months) and late fattening stages (22-30 months), respectively. The results of the present study and future genotypic data for Hanwoo beef cattle based on the robust genetic variation of IGF1 will provide critical information for genetic improvement and will have a large impact on commercial markets.

The germanosilicate ITQ-24 (IWR framework type) was synthesized in fluoride medium using 1,3,5-tris(1,2-dimethylimidazolium) benzene as the structure directing agent (SDA). A structure analysis of the as-synthesized ITQ-24 material using synchrotron powder diffraction data and difference electron density calculations have allowed the fluoride ions and the germanium atoms to be located and the conformation of the SDA to be determined. The benzyl ring is perpendicular to the b axis with the three imidazolium moieties forming a "T-shaped" arrangement. Ge atoms replace some of the Si in the double-4-ring (d4r) and in one of the single-4-rings (s4r). The other s4r contains only Si. Fluoride ions are in the d4r units. Initially, the space group Cmmm (highest possible symmetry) was assumed, but the framework geometry was strained. An independent evaluation of the symmetry using the powder charge flipping algorithm in Superflip led to a successful refinement with reasonable geometry and a refined composition of |[(C6H3)(C7H10N2)3]2F2|[Si(40.2)Ge(15.8)O112] in the space group Pban.

The objective of this study was to evaluate the relationship between hepatic mitochondrial function and residual feed intake (RFI) in growing beef cattle. In Trial 1, RFI was measured in 29 Angus heifers (initial BW = 258.0 ± 24.9 kg) from divergent IGF-I selection lines created at the Eastern Agricultural Research Station (The Ohio State University) fed a grain-based diet (calculated ME = 2.85 Mcal/kg DM). In Trial 2, RFI was measured in 119 Santa Gertrudis steers (initial BW = 308.4 ± 28.1 kg) fed a roughage-based diet (calculated ME = 2.21 Mcal/kg DM). At the end of the RFI measurement period, cattle in Trial 1 (n = 7 low RFI and n = 7 high RFI) and in Trial 2 (n = 6 low RFI and n = 8 high RFI) with measures of RFI exceeding 0.5 (Trial 1) or 1.0 (Trial 2) SD from the mean RFI were selected to measure mitochondrial function. Overall ADG, DMI, and RFI were 1.19 ± 0.15, 9.31 ± 1.12, and 0.00 ± 0.63 kg/d and 0.83 ± 0.16, 9.48 ± 1.00, and 0.00 ± 0.86 kg/d in Trial 1 and 2, respectively. Cattle with low RFI consumed 13 and 24% less (P < 0.05) DM and had 14 and 56% greater (P < 0.05) G:F than cattle with high RFI in Trial 1 and 2, respectively, even though ADG and BW were similar (P > 0.10). In Trial 1, cattle with low RFI tended (P = 0.06) to have greater state 3 respiration rates than cattle with high RFI, but state 3 respiration rates were similar (P > 0.10) between cattle with low and high RFI in Trial 2. In both trials, cattle with low RFI had greater (P < 0.05) acceptor control ratios than their high RFI counterparts. The respiratory control ratio tended (P = 0.09) to be greater for cattle with low RFI compared with high RFI cattle in Trial 1, but no difference (P > 0.10) was observed in Trial 2. Proton-leak kinetics were similar (P > 0.05) between cattle with low and high RFI in both trials. These data suggest that ADP has greater control of oxidative phosphorylation in liver mitochondrial of cattle with low RFI compared to their high RFI counterparts.

Increase of fat cells (FCs) in adipose tissue is attributed to proliferation of preadipocytes or immature adipocytes in the early stage, as well as adipogenic differentiation in the later stage of adipose development. Although both events are involved in the FC increase, they are contrary to each other, because the former requires cell cycle activity, whereas the latter requires cell cycle withdrawal. Therefore, appropriate regulation of cell cycle inhibition is critical to adipogenesis. In order to explore the important cell cycle inhibitors and study their expression in adipogenesis, we adopted a strategy combining the Gene Expression Omnibus (GEO) database available on the NCBI website and the results of quantitative real-time PCR (qPCR) data in porcine adipose tissue. Three cell cycle inhibitors - cyclin G2 (CCNG2), cyclin-dependent kinase inhibitor 2C (CDKN2C) and peripheral myelin protein (PMP22) - were selected for study because they are relatively highly expressed in adipose tissue compared with muscle, heart, lung, liver and kidney in humans and mice based on two GEO DataSets (GDS596 and GDS3142). In the latter analysis, they were found to be more highly expressed in differentiating/ed preadipocytes than in undifferentiated preadipocytes in human and mice as shown respectively by GDS2366 and GDS2743. In addition, GDS2659 also suggested increasing expression of the three cell cycle inhibitors during differentiation of 3T3-L1 cells. Further study with qPCR in Landrace pigs did not confirm the high expression of these genes in adipose tissue compared with other tissues in market-age pigs, but confirmed higher expression of these genes in FCs than in the stromal vascular fraction, as well as increasing expression of these genes during in vitro adipogenic differentiation and in vivo development of adipose tissue. Moreover, the relatively high expression of CCNG2 in adipose tissue of market-age pigs and increasing expression during development of adipose tissue was also confirmed at the protein level by western blot analysis. Based on the analysis of the GEO DataSets and results of qPCR and Western blotting we conclude that all three cell cycle inhibitors may inhibit adipocyte proliferation, but promote adipocyte differentiation and hold a differentiated state by inducing and maintaining cell cycle inhibition. Therefore, their expression in adipose tissue is positively correlated with age and mature FC number. By regulating the expression of these genes, we may be able to control FC number, and, thus, reduce excessive fat tissue in animals and humans.

Reproductive performance of animals affects lifetime productivity. However, improvement of reproductive traits via direct selection is generally slow due to low heritability. Therefore, identification of indicator traits for reproductive performance may enhance genetic response. Previous studies showed that serum IGF-I concentration is a candidate indicator for growth and reproductive traits. The objective of our study was to estimate the variances or covariances of IGF-I concentration with reproductive traits. Data were collected from a divergent selection experiment for serum IGF-I concentration at the Eastern Agricultural Research Station owned by The Ohio State University. The study included a total of 2,662 calves in the 1989 to 2005 calf crops. Variance or covariance components were estimated for direct and maternal genetic effects, maternal environment effects, environment effects, and phenotypic effects using an animal model in a multiple-trait, derivative-free, restricted maximum likelihood (MTDFREML, Boldman et al., 1995) computer program. Direct additive genetic correlations suggest that selection for greater IGF-I concentration (heritability = 0.50 ± 0.07) could lead to increased conception rate (heritability = 0.11 ± 0.06, r = 0.32, P < 0.001) and calving rate (heritability = 0.13 ± 0.06, r = 0.43, P < 0.001) and decreased age at first calving in heifers (heritability = 0.35 ± 0.20, r = -0.40, P < 0.001).

Ice cores from low latitudes can provide a wealth of unique information about past climate in the tropics, but they are difficult to recover and few exist. Here, we report annually resolved ice core records from the Quelccaya ice cap (5670 meters above sea level) in Peru that extend back ~1800 years and provide a high-resolution record of climate variability there. Oxygen isotopic ratios (δ(18)O) are linked to sea surface temperatures in the tropical eastern Pacific, whereas concentrations of ammonium and nitrate document the dominant role played by the migration of the Intertropical Convergence Zone in the region of the tropical Andes. Quelccaya continues to retreat and thin. Radiocarbon dates on wetland plants exposed along its retreating margins indicate that it has not been smaller for at least six millennia.

A meta-analysis was conducted to examine phenotypic relationships between feed efficiency, scrotal circumference, and semen quality traits in yearling bulls. Data evaluated were obtained from 5 postweaning trials involving Angus (n = 92), Bonsmara (n = 62), and Santa Gertrudis (n = 50) bulls fed diets that ranged from 1.70 to 2.85 Mcal ME/kg DM. After an adaptation period of 24 to 28 d, feed intake was measured daily, and BW was measured at 7- or 14-d intervals during the 70- to 77-d trials. Ultrasound carcass traits (12th-rib back fat thickness, BF; LM area, LMA) and scrotal circumference (SC) were measured at the start and end of each trial. Semen samples were collected by electroejaculation within 51 d of the end of the trials when the age of bulls averaged from 365 to 444 d and were evaluated for progressive sperm motility and morphology. Residual feed intake (RFI) was calculated as the difference between actual DMI and expected DMI from linear regression of DMI on ADG and midtest BW(0.75), with trial, trial by ADG, and trial by midtest BW(0.75) as random effects. Across all studies, bulls with low RFI phenotypes (<0.5 SD below the mean RFI of 0) consumed 20% less DM and had 10% less BF but had similar ADG, SC, and semen quality traits compared with high-RFI bulls (>0.5 SD above the mean RFI of 0). Gain to feed ratio was strongly correlated with ADG (0.60) and weakly correlated with initial BW (-0.17) and DMI (-0.26). Residual feed intake was not correlated with ADG, initial age, or BW but was correlated with DMI (0.71), G:F (-0.70), and BF (0.20). Initial SC (-0.20), gain in SC (-0.28), and percent normal sperm (-0.17) were correlated with G:F, but only sperm morphology was found to be weakly associated with RFI (0.13). These data suggest that RFI is not phenotypically associated with SC or sperm motility but is weakly associated with sperm morphology.

A divergent selection experiment for serum IGF-I concentration was established in 1989 at the Eastern Agricultural Research Station located in Belle Valley, Ohio. One hundred spring-calving (50 high line and 50 low line) and 100 fall-calving (50 high line and 50 low line) cows with unknown IGF-I concentrations were randomly assigned to the 2 divergent selection lines. Results of this study included 2,507 calves from the 1989 through 2005 calf crops. (Co)variance components were estimated for direct and maternal additive genetic effects using an animal model and multiple-trait, derivative-free, REML (MTDFREML) computer programs. Estimated breeding values were also obtained and regressed on years to estimate direct and correlated responses to divergent selection for serum IGF-I concentration. Estimates of direct heritability for growth traits from a single trait model were moderate and ranged from 0.33 ± 0.06 for birth weight to 0.42 ± 0.06 for preweaning BW gain. Heritability estimates for direct effects were 0.44 ± 0.07, 0.43 ± 0.07, 0.35 ± 0.06, and 0.48 ± 0.07 for IGF-I concentration at d 28, 42, and 56 of the 140-d postweaning period, and for mean IGF-I concentration, respectively. Maternal heritability and the proportion of phenotypic variance due to permanent environment effect of dam were ≤0.25 for growth traits and IGF-I concentrations. Cattle in the high line had significantly (P < 0.001) greater direct effects of mean IGF-I concentration than those in low line (high line: 66.92 ± 4.40 ng/mL vs. low line: -40.82 ± 5.18 ng/mL) in 2005. Direct responses per year for mean IGF were 5.18 ng/mL in the high line and -3.76 ng/mL in the low line. The regression of direct effects of preweaning BW gain on year were not significantly different from zero in either the high or low line. However, genetic trends were negative and significant for birth weight and postweaning BW gain in the high line and were positive and significant in the low line. Results demonstrated that divergent selection for serum IGF-I concentration in beef cattle will change the genetic potential for IGF-I concentration and that selection for lesser IGF-I concentration will result in increased birth weights and postweaning BW gains.

Relationships of the calpain system with meat tenderness and carcass traits were examined for 94 purebred Angus bulls with genotypes of the calpain classified by RFLP (restriction fragment length polymorphism) and SSCP (Single strand conformation polymorphism) analysis. Designing of primers based on the calpain regulatory subunit (CAPNS) and u-calpian (CAPN1) genes. Bulls from 15 months of age were slaughtered, and carcass traits, including fat thickness (FAT); longissimus muscle area (LMA); percentage of kidney, pelvic, and heart fat (KPH); hot carcass weight (HCW); marbling score (MAR); and quality grade (QUL), were analyzed. Measurements regarding meat tenderness involved activities of calpastatin (CAC), u-calpain (UAC), m-calpain (MAC), Warner-Bratzler Shear Force (WBS) and myofibril fragmentation index (MFI). Statistical significances of the calpain genotypes accounted for variations in MAR and QUL at CAPNS locus, and both loci explained variations of UAC and MAC. Significant mean differences in genotypes of CAPNS locus were found for MAR (BB > AB > AA) and QUL (AB > BB > AA). UAC showed significant correlations with MAC, CAC, MFI, FAT, and MAR, and we found that MAC correlated with WBS, FAT, HCW, MAR, and QUL. Strong positive correlation detected between LMA and HCW, and MAR and QUL, and a negative correlation between MFI and MAR was estimated. From the result it may be possible to use the calpain genotypes classified by RFLP and SSCP analysis in marker assisted selection programs to estimate UAC and MAC precisely regardless meat tenderness and to improve MAR and QUL of beef cattle.

Data for the current study were obtained from a divergent selection experiment in which the selection criterion was the average serum IGF-I concentration of 3 postweaning blood samples collected from purebred Angus calves. Multiple trait derivative-free REML procedures were used to obtain estimates of inbreeding depression for IGF-I concentration and for BW and BW gains measured from birth to the conclusion of a 140-d postweaning performance test. Included in the analysis were 3,243 animals in the A(-1) matrix, 2,182 of which had valid records for IGF-I concentration. Over the course of the entire selection experiment, inbreeding of the calf averaged 3.3% (SD = 3.1%) and inbreeding of the dam averaged 1.8% (SD = 2.7%). Mean inbreeding levels at the end of the study were 6.82 +/- 0.38% and 4.20 +/- 0.36% for calves and dams, respectively. Annual rates of increase in inbreeding of calves and dams were 0.36 +/- 0.01 (P < 0.0001) and 0.25 +/- 0.01%/yr (P < 0.0001), respectively. Insulin-like growth factor I concentration at d 28 (IGF28), 42 (IGF42), and 56 (IGF56) of the 140-d postweaning test and mean IGF-I concentration decreased by 0.62 +/- 0.88, 1.86 +/- 0.96, 1.92 +/- 0.89, and 1.48 +/- 0.76 ng/mL per 1% increase in inbreeding of calf. Only the regression coefficient for IGF56 differed significantly from zero, although the regression coefficients for IGF42 and mean IGF-I approached significance (P < 0.10). Increases in inbreeding levels of the dams also tended to result in reduced IGF-I concentrations, although the regression coefficients were not significantly different from zero. Inbreeding of calf had highly significant negative effects on all BW and BW gain traits examined, except for birth weight, with regression coefficients ranging from -0.74 +/- 0.20 kg/% increase in calf inbreeding for postweaning BW gain to -1.68 +/- 0.33 kg/% increase in calf inbreeding for off-test BW. Inbreeding of dam had a significant negative effect on birth weight of progeny and tended to have a negative effect on postweaning BW gain (P < 0.10). Preweaning gain of the progeny and BW other than birth weight were not influenced by increases in dam inbreeding. Results indicate that reductions in serum IGF-I concentration due to inbreeding may contribute to the decline in BW and BW gains that is typically associated with increases in inbreeding within populations.

The objective of this research was to further characterize the promoter regions of the bovine and porcine fatty acid-binding protein 4 (FABP4) genes relative to those of other mammals. The DNA sequences of FABP4 promoters for the human, mouse, cow, pig, and dog were obtained from the genomic database of the National Center for Biotechnology Information and also from the sequencing of bovine and porcine genomic DNA clones obtained by 5' PCR racing of genomic DNA. Sequence alignments of these FABP4 promoters using the basic local alignment search tool of the National Center for Biotechnology Information revealed 3 highly conserved promoter regions across the species. Two computational bioinformatics databases and the literature identified the conserved transcription factor-binding sites for C/EBP, adapter primer-1, and boxes of CAAT and TATA in the first conserved proximal promoter region, a direct repeat 1-type PPAR responsive element in the second distal conserved region, and another PPAR responsive element in the third distal conserved promoter region of FABP4 in all 5 mammals. Five new short interspersed repetitive elements (SINE) in the bovine FABP4 promoter and 2 new SINE in the porcine were found, but these SINE did not disrupt the 3 conserved regions, indicating that important regulatory elements are maintained regardless of evolutionary pressure. In conclusion, the conserved cis-acting elements, especially the 2 key adipocyte transcription factors C/EBP and PPAR, may contribute greatly to adipogenic regulation and adipose tissue-specific expression of FABP4 in these mammals. This helps to further characterize and decipher important cis-acting elements that are important for adipocyte development in adipose and muscle tissue.

A Bacillus-based direct-fed microbial (DFM), Omni-BosCB™, added to an electrolyte was evaluated as a therapy for scours. Fecal shedding of presumptive Clostridium perfringens at day 7 was reduced in scouring calves treated with electrolyte plus DFM compared to scouring calves treated with electrolyte alone. Total therapeutic treatment costs during the first 2 weeks were significantly reduced by supplementing the electrolyte with the DFM: $18.69 and $21.57 for electrolyte plus DFM and electrolyte treated calves, respectively. Electrolyte treated calves experienced more severe scours than electrolyte plus DFM treated calves as additional therapy with Lactated Ringer's Solution was only necessary for electrolyte treated calves. The DFM may have other ancillary benefits after supplementation has ended, as evidenced by decreased recurrence of a second scouring event. This is the first report demonstrating efficacy of a DFM used therapeutically for mitigating calf scours. These findings have implications as alternatives to chemical interventions for disease control.

Angus bulls and heifers from lines divergently selected for serum IGF-I concentration were used to evaluate the effects of IGF-I selection line on growth performance and feed efficiency in 2 studies. In study 1, bulls (low line, n = 9; high line, n = 8; initial BW = 367.1 +/- 22.9 kg) and heifers (low line, n = 9; high line, n = 13; initial BW = 286.4 +/- 28.6 kg) were adapted to a roughage-based diet (ME = 1.95 Mcal/kg of DM) for 24 d and fed individually for 77 d by using Calan gate feeders. In study 2, bulls (low line, n = 15; high line, n = 12; initial BW = 297.5 +/- 34.4 kg) and heifers (low line, n = 9; high line, n = 20; initial BW = 256.0 +/- 25.1 kg) were adapted to a grain-based diet (ME = 2.85 Mcal/kg of DM) for 32 d and fed individually for 70 d by using Calan gate feeders. Blood samples were collected at weaning and at the start and end of each study, and serum IGF-I concentration was determined. Residual feed intake (RFI) was calculated, within study, as the residual from the linear regression of DMI on midtest BW(0.75), ADG, sex, sex by midtest BW(0.75) and sex by ADG. In study 1, calves from the low IGF-I selection line had similar initial and final BW and ADG, compared with calves from the high IGF-I selection line. In addition, DMI and feed conversion ratio were similar between IGF-I selection lines; however, calves from the low IGF-I selection line tended (P < 0.10) to have lesser RFI than calves from the high IGF-I selection line (-0.26 vs. 0.24 +/- 0.31 kg/d). In study 2, IGF-I selection line had no influence on performance or feed efficiency traits. However, there was a tendency (P = 0.15) for an IGF-I selection line x sex interaction for RFI. Bulls from the low IGF-I selection line had numerically lesser RFI than those from the high IGF-I selection line, whereas in heifers, the IGF-I selection line had no effect on RFI. In studies 1 and 2, weaning and initial IGF-I concentrations were not correlated with either feed conversion ratio or RFI. However, regression analysis revealed a sex x IGF-I concentration interaction for initial IGF-I concentration in study 1 and weaning IGF-I concentration in study 2 such that the regression coefficient was positive for bulls and negative for heifers. These data suggest that genetic selection for postweaning serum IGF-I concentration had a minimal effect on RFI in beef cattle.

A direct-fed microbial (DFM) based on a combination of Bacillus organisms specifically selected to increase the manure decomposition process was evaluated to determine its efficacy for improving growth performance and manure dissolution time. Three experiments involving 336 crossbred barrows and gilts were conducted to determine the effect of the Bacillus-based direct-fed microbial on growth performance and pen cleaning time. In each experiment, 2 dietary treatments (0 and 0.05% DFM) were fed during the growing-finishing period throughout the experiment, such that the DFM provided 1.47 x 10(8) cfu of Bacillus organisms per gram of supplement. Data from the 3 experiments were combined for analysis, such that there were 28 pens representing each of the 2 treatments. Pigs were weighed and feed intake was determined at the initiation and termination of each phase (starter, grower, and finisher). At the end of Exp. 1 and 3, pen cleaning time was determined by measuring the time required for each pen to be scraped and washed with a high-pressure sprayer. Additionally, 2 solid manure mat samples weighing approximately 4 g each were collected from solid manure buildup in each pen (16 pens/treatment), and the time required to completely disperse each manure mat sample was determined. Gain:feed improved (P < 0.05) in pigs fed Bacillus compared with the control diet during the finisher phase and throughout the combined growing-finishing period. The time required to dissolve the manure mat was reduced (P < 0.01) in samples collected from pens containing pigs fed Bacillus compared with samples from control pens. An additional evaluation was conducted in a commercial swine production facility using statistical process control analysis. Statistical process control analysis determined that supplementation with Bacillus increased the expected mean for ADG and decreased the expected mean for death loss percentage. Supplementation with a DFM composed of specifically selected Bacillus organisms improved G:F and decreased the time required to disperse a swine manure mat sample in a controlled study conducted at swine research facilities. Furthermore, when evaluated in a commercial swine production facility, the Bacillus-based DFM improved ADG and reduced mortality of pigs during the growing-finishing period.

A large study of combustion particle exposures for drivers of diesel-powered trucks was conducted in collaboration with an epidemiologic study of lung cancer outcomes for workers in the trucking industry. Three components of diesel exhaust combustion particles (PM(2.5), elemental carbon, and organic carbon) were measured inside the driver cabs of diesel-powered trucks from 36 different trucking terminals across the United States between 2001 and 2005. In-cab particle exposures for drivers assigned to both short and long distance trips were observed, as well as information on the smoking status of the driver, truck characteristics such as age and model, and weather conditions during the sampling session. This article summarizes these findings and describes the relationship between exhaust particles and various determinants of exposure. The results suggest that in-cab particle exposures are positively related to smoking, ambient particle concentrations, truck age, and open windows, with other significant modifying factors such as weather. This study represents the largest and most comprehensive exposure assessment of drivers in the trucking industry, encompassing a 4-year period of observations on diesel and exhaust particle exposures nationwide. The results are relevant not only to the occupational group of truck drivers being examined but also to the general population that live, commute, or work within proximity to diesel-fueled traffic or trucking terminals.

Diesel exhaust is a complex chemical mixture that has been linked to lung cancer mortality in a number of epidemiologic studies. However, the dose-response relationship remains largely undefined, and the specific components responsible for carcinogenicity have not been identified. Although previous focus has been on the particulate phase, diesel exhaust includes a vapor phase of numerous volatile organic compounds (VOCs) and aldehydes that are either known or suspected carcinogens, such as 1,3-butadiene, benzene, and formaldehyde. However, there are relatively few studies that quantify exposure to VOCs and aldehydes in diesel-heavy and other exhaust-related microenvironments. As part of a nationwide assessment of exposure to diesel exhaust in the trucking industry, we collected measurements of VOCs and aldehydes at 15 different U.S. trucking terminals and in city truck drivers (with 6 repeat site visits), observing average shift concentrations in truck cabs and at multiple background and work area locations within each terminal. In this paper, we characterize occupational exposure to 18 different VOCs and aldehydes, as well as relationships with particulate mass (elemental carbon in PM < 1 microm and PM2.5) across locations to determine source characteristics. Our results show that occupational exposure to VOCs and aldehydes varies significantly across the different sampling locations within each terminal, with significantly higher exposures noted in the work environments over background levels (p < 0.01). A structural equation model performed well in predicting terminal exposures to VOCs and aldehydes as a function of job, background levels, weather conditions, proximity to a major road, and geographic location (R2 = 0.2-0.4 work area; R2 = 0.5-0.9 background).

Crossbred pigs (n = 216) were used to test the interaction, if any, of ractopamine (RAC) and dietary fat source on the characteristics of fresh pork bellies. Pigs were blocked by BW (77.6 +/- 6.5 kg) and allotted randomly to pens (6 pigs/pen). After receiving a common diet devoid of RAC for 2 wk, pens within blocks were assigned randomly to 1 of 4 treatments arranged in a 2 x 2 factorial design, with 5% fat (beef tallow vs. soybean oil) and RAC (0 vs. 10 mg/kg). At the conclusion of the 35-d feeding period, pigs were slaughtered at a commercial pork packing plant (average BW of 108.8 +/- 0.6 kg), and fresh bellies were captured during carcass fabrication. Neither RAC (P = 0.362) nor fat source (P = 0.247) affected belly thickness. Subjective (bar-suspension) or objective (compression test) measures of belly firmness were not (P > or = 0.148) affected by the inclusion of RAC in the diet; however, bellies from pigs fed soybean oil (SBO) were softer than those from pigs fed beef tallow (BT), as indicated by perpendicular (P < or = 0.005) and parallel (P < 0.001) suspensions. Moreover, bellies from BT-fed pigs required more (P = 0.096) force to compress 50% of their thickness than bellies from SBO-fed pigs (52.29 vs. 43.51 kg). Color (L*, a*, and b* values) of the belly lean and fat was not (P > or = 0.131) affected by RAC, and lean color was similar (P > or = 0.262) between fat sources; however, belly fat from BT-fed pigs was lighter (P = 0.030) and redder (P = 0.013) in color than belly fat from SBO-fed pigs. Bellies of SBO-fed pigs had greater (P < 0.001) proportions of PUFA and lower (P < 0.001) proportions of SFA and MUFA than belly fat from pigs fed BT. Regardless of the RAC inclusion level, PUFA:SFA and iodine values were lower in belly fat from pigs fed BT than SBO; however, within SBO-fed pigs, PUFA:SFA and iodine values were further increased by feeding RAC (RAC x fat source, P < 0.001). As expected, dietary fat source altered the fatty acid composition of fresh pork bellies, which subsequently impacted fresh belly firmness. Interestingly, including RAC in swine finishing diets exacerbated the effect of feeding SBO on pork fat polyunsaturation.

Rate coefficients for the gas-phase reaction of the OH radical with (E)-2-pentenal (CH(3)CH(2)CH[double bond]CHCHO), (E)-2-hexenal (CH(3)(CH(2))(2)CH[double bond]CHCHO), and (E)-2-heptenal (CH(3)(CH(2))(3)CH[double bond]CHCHO), a series of unsaturated aldehydes, over the temperature range 244-374 K at pressures between 23 and 150 Torr (He, N(2)) are reported. Rate coefficients were measured under pseudo-first-order conditions in OH with OH radicals produced via pulsed laser photolysis of HNO(3) or H(2)O(2) at 248 nm and detected by pulsed laser-induced fluorescence. The rate coefficients were independent of pressure and the room temperature rate coefficients and Arrhenius expressions obtained are (cm(3) molecule(-1) s(-1) units): k(1)(297 K)=(4.3 +/- 0.6)x 10(-11), k(1)(T)=(7.9 +/- 1.2)x 10(-12) exp[(510 +/- 20)/T]; k(2)(297 K)=(4.4 +/- 0.5)x 10(-11), k(2)(T)=(7.5 +/- 1.1)x 10(-12) exp[(520 +/- 30)/T]; and k(3)(297 K)=(4.4 +/- 0.7)x 10(-11), k(3)(T)=(9.7 +/- 1.5)x 10(-12) exp[(450 +/- 20)/T] for (E)-2-pentenal, (E)-2-hexenal and (E)-2-heptenal, respectively. The quoted uncertainties are 2sigma(95% confidence level) and include estimated systematic errors. Rate coefficients are compared with previously published room temperature values and the discrepancies are discussed. The atmospheric degradation of unsaturated aldehydes is also discussed.

Data for the current study were obtained from a divergent selection experiment in which the selection criterion was the average serum IGF-I concentrations of 3 postweaning blood samples collected from purebred Angus calves. Multiple-trait derivative-free REML procedures were used to obtain genetic parameter estimates for IGF-I concentrations and for BW and BW gains measured from birth to the conclusion of a 140-d postweaning performance test. Included in the analysis were 2,674 animals in the A(-1) matrix, 1,761 of which had valid records for IGF-I concentrations. Direct heritability estimates +/- SE for IGF-I concentration at d 28, 42, and 56 of the postweaning period and for mean IGF-I concentrations were 0.44 +/- 0.07, 0.51 +/- 0.08, 0.42 +/- 0.07, and 0.52 +/- 0.08, respectively. Heritability estimates for maternal genetic effects ranged from 0.10 +/- 0.05 to 0.20 +/- 0.06. The proportion of total phenotypic variance due to the maternal permanent environmental effect was essentially zero for all measures of IGF-I concentrations. Genetic correlations of IGF-I concentrations with weaning and post-weaning BW ranged from 0.07 +/- 0.12 to 0.32 +/- 0.11 and generally demonstrated an increasing trend during the postweaning period. Averaged across the various measures of IGF-I, the genetic correlation of IGF-I with preweaning gain was 0.14, whereas the genetic correlation with postweaning gain was 0.29. Genetic correlations between IGF-I and BW gain were positive during all time intervals, except between weaning and the beginning of the postweaning test and from d 84 to 112 of the postweaning period. Environmental and phenotypic correlations of IGF-I with BW and BW gains were generally positive, but small. These results indicate that postweaning serum IGF-I concentration is moderately to highly heritable and has small positive genetic, environmental, and phenotypic correlations with BW other than birth weight and with pre- and postweaning gain. Therefore, if IGF-I proves to be a biological indicator of an economically important trait (e.g., efficiency of feed use for growth) in beef cattle, it should be possible to rapidly change IGF-I concentrations via selection without significantly altering live weight or rate of gain.

Multi-tiered sampling approaches are common in environmental and occupational exposure assessment, where exposures for a given individual are often modeled based on simultaneous measurements taken at multiple indoor and outdoor sites. The monitoring data from such studies is hierarchical by design, imposing a complex covariance structure that must be accounted for in order to obtain unbiased estimates of exposure. Statistical methods such as structural equation modeling (SEM) represent a useful alternative to simple linear regression in these cases, providing simultaneous and unbiased predictions of each level of exposure based on a set of covariates specific to the exposure setting. We test the SEM approach using data from a large exposure assessment of diesel and combustion particles in the U.S.trucking industry. The exposure assessment includes data from 36 different trucking terminals across the United States sampled between 2001 and 2005, measuring PM2.5 and its elemental carbon (EC), organic carbon (OC) components, by personal monitoring, and sampling at two indoor work locations and an outdoor "background" location. Using the SEM method, we predict the following: (1) personal exposures as a function of work-related exposure and smoking status; (2) work-related exposure as a function of terminal characteristics, indoor ventilation, job location, and background exposure conditions; and (3) background exposure conditions as a function of weather, nearby source pollution, and other regional differences across terminal sites. The primary advantage of SEMs in this setting is the ability to simultaneously predict exposures at each of the sampling locations, while accounting for the complex covariance structure among the measurements and descriptive variables. The statistically significant results and high R2 values observed from the trucking industry application supports the broader use of this approach in exposure assessment modeling.

At time of weaning, the immune system in piglets is not fully mature resulting in reduced growth and increased mortality. Early-weaned pigs transported to a segregated early weaning (SEW) facility have enhanced performance and gut development compared to conventional (CONV) pigs which may be due, in part, to decreased pathogen challenge. To gain further insight into SEW enhanced performance and gut development, gut samples from pigs weaned at 19+/-2 days were assessed during the post-weaning (PW) period. The numbers of cells expressing CD2, CD4, CD8, and CD172 (the 74-22-15 (SWC3) antibody is now known to be specific for CD172), MHC class II, and CD25 were quantified using immunohistochemistry. Additionally, samples of duodenum, jejunum, and ileum were evaluated for the production of neutral, acidic, and sulfuric mucins from goblet cells and morphological measurements were also made. No effects due to the management systems alone were observed for any of the parameters. However, there were interactive effects of age/time post-weaning and management system on the immune cells as well as on the mucin secreting goblet cells. There were no differences in gut morphology between SEW and CONV reared pigs.

Insulin-like growth factor-I (IGF-I) is an anabolic polypeptide involved in reproductive performance in several species. The objectives of this study were to determine relationships of pregnancy rate, and age of heifers at puberty and at first calving with serum IGF-I concentration in Angus beef cattle. Data were obtained from an ongoing divergent selection experiment for IGF-I concentration involving purebred Angus cows. The IGF-I concentrations measured at Days 28, 42, and 56 of the 140-day postweaning test are abbreviated as IGF28, IGF42, and IGF56, respectively. Pregnancy rate did not differ between high and low IGF-I line females (P=0.95; n=2618), but high line heifers tended to be 4.02+/-2.18 days younger (P=0.07; n=281) at first calving. Residual correlations of age of heifers at first calving (AFC) with IGF-I measurements were not significant. The linear and quadratic terms for regression of AFC on IGF-I concentrations were also non-significant. Contrast analysis showed no difference in age at puberty between the high and low IGF-I line heifers (5.3+/-6.4 days earlier in the high line; P=0.43; n=51). Residual correlations of age of heifers at puberty with IGF28, IGF42, IGF56, and mean IGF-I were -0.30 (P=0.03), -0. 22 (P=0.12), -0.35 (P=0.01), and -0.34 (P=0.01), respectively. The observed relationships between female reproductive traits and IGF-I concentration in Angus beef cattle suggest complex and multiple roles for IGF-I in reproduction.

Pigs from one farrowing group in which gilts were bred to farrow pigs that would be either 14 or 21 d of age at weaning, were divided into older and younger age groups (108 pigs per group) and penned 12 pigs per pen in a wean-to-finish facility. At the end of the nursery phase, half the pigs in each age group were removed, rerandomized, and commingled for the finishing phase. The other half remained in their original pens. Pigs were fed common Phase 1 (d 0 to 14) and Phase 2 (d 14 to 35) nursery diets, and a common 4-phase program diet during growing/finishing, with transitions at 45, 68, and 90 kg of BW. The study ended when the lightest weight block averaged 107 kg. Blood was obtained on d 0, 2, 10, 27, 37, 44, and 65 after weaning to determine leukocyte concentrations. In addition, behavior was monitored during the nursery period at weaning (d 0), on d 7, 14, and 27 after weaning, and during the growing/finishing phase on d 35 (after commingling following the nursery phase), 38, 44, and 65 after weaning. Older pigs were heavier (P < 0.001) throughout the nursery period, and the BW difference between younger and older pigs increased from 2 to 6.5 kg at the start and end of the nursery period, respectively. Older pigs had a greater concentration of white blood cells (P < 0.05) and lymphocytes (P < 0.10) on d 0, 2, and 10 after weaning than younger pigs. Younger pigs spent less (P < 0.05) time resting on the day of weaning, and more (P < 0.05) time active during the overall nursery phase. During Phase 3 and in the overall finishing phase, younger pigs had greater (P < 0.01) ADG and G:F than older pigs. Moreover, during Phase 3, ADFI (as fed) decreased (P < 0.05) when older pigs were commingled compared with older pigs that were not commingled. There was no difference in ADFI of younger pigs, regardless of commingling (interaction; P < 0.10). Results of this study indicate that weaning age affects growth performance in a wean-to-finish facility, as well as behavioral and immunological responses to weaning and commingling after the nursery phase. Management strategies should be further explored to optimize these benefits without the detrimental effects on health observed during the nursery period in this study.

To evaluate morphological characteristics and development of the immune system at different ages in neonatal pigs, 4 piglets were euthanized at 7, 14, and 18 d of age for collection of blood, bile, and intestinal tissue for morphological measurements. Blood was collected for differential cell counts, lymphocyte blastogenesis, immunoglobulin (Ig) concentrations, cytokine concentrations, and flow cytometric analysis. Bile was collected for quantification of Ig-A and Ig-M. Villus width and crypt depth from duodenum sections, as well as ileum crypt depth, were reduced (P < or = 0.08) in 18-d-old pigs compared with 7-d-old pigs. No age-related differences (P > or = 0.11) were observed in the number of goblet cells with neutral and acidic mucins, serum or enteric Ig concentrations, IL-2, IL-4, spontaneous lymphocyte proliferation, or leukocyte concentrations. When measured as counts per minute (cpm) and as a stimulation index (SI), lymphocyte proliferation responses to phytohaemagglutinin increased (P = 0.05) between 7 and 14 d of age; no changes (P = 0.10) occurred at 18 d of age. No age-related changes (P = 0.39) were observed in response to pokeweed mitogen (PWM) when measured as cpm; however, the SI from PWM-induced lymphocytes decreased (P = 0.04) 4-fold between 7 and 18 d of age. The CD4+:CD8+ and populations of lymphocytes expressing CD2+CD4+CD8- (T helper cells) and CD25+CD4+CD8- (activated T helper cells) were greater (P > or = 0.04) at 7 d of age than at 14 and 18 d. Populations of T lymphocytes, cytotoxic T cells (CD2+CD4-CD8+), activated lymphocytes (CD25+), and activated cytotoxic T cells (CD25+CD4-CD8+) were greater (P > or = 0.02) in 18-d-old pigs compared with 7-d-old pigs, whereas CD2+CD4-CD8- [double negative cells] were lower (P = 0.08) in 18-d-old pigs compared with 14-d-old pigs. The percentage of CD2+ T cells was 8.4% at 7 d of age, and by the time the pigs reached 18 d of age, the percentage of CD2+ T cells was 33.8%. Moreover, the percentage of gammadelta T cells was greater (P = 0.02) in 18-d-old pigs than in 7-d-old pigs (74.8 vs. 46.1%, respectively). Results indicate that the porcine immune system and gut are continuously changing as the young pig matures. Changes occurred in lymphocyte phenotypic expression and functional capabilities, as well as morphology and mucin production, and their role may be to further protect the neonate from antigenic challenge as protection from passive immunity declines.

A study was conducted to determine the effects of supplemental fish oil on growth performance and immune system characteristics of beef calves. The grazing phase (78 d) used 48 yearling crossbred steers (231 +/- 22 kg initial BW) grazing 0.45-ha mixed-grass pastures (four per treatment) supplemented with 1.82 kg/d (as-fed basis) of the diets. Diets consisted of 1) corn-based supplement; 2) corn-based supplement with 1.5% (as-fed basis) fish oil; 3) wheat midd-based supplement; and 4) wheat midd-based supplement with 1.5% fish oil. On d 78, all calves were bled by jugular venipuncture, and blastogenic response of peripheral blood lymphocytes to phytohemagglutinin, concanavalin A, and pokeweed mitogen was measured. Fish oil supplementation negatively affected ADG with the corn-based supplement, but it had no effect when added to the wheat midd-based supplement (base-supplement x fish oil interaction; P < 0.03). Isolated lymphocytes from calves fed the corn-based supplement with fish oil had a greater response to stimulation with concanavalin A than did lymphocytes from calves fed the corn-based supplement alone, but there was no effect of fish oil addition to the wheat midd-based supplement (base-supplement x fish oil interaction; P < 0.01). During the growing phase, the 48 steers (352 +/- 32 kg initial BW) from the grazing phase were moved to drylot pens and were stratified by BW and previous dietary treatment (three calves per pen; eight pens per dietary treatment) for a 56-d growing trial. Dietary treatments consisted of 1) control, and 2) the control diet with 3% (as-fed basis) fish oil. Calves supplemented with fish oil had decreased ADG, ADFI, and G:F (P < or = 0.02) compared with controls. Fish oil supplementation during the grazing phase modulated the immune system; however, the decreased growth performance associated with fish oil in both trials may limit its practical use as an immune stimulant.

We investigated the epidemiology of systemic lupus erythematosus (SLE) in the Marshfield Epidemiologic Study Area (MESA), a defined rural region where nearly all residents obtain their health care from a large clinic system. Computerized medical records were searched to identify MESA residents diagnosed with SLE from 1991 through 2001. Medical records were manually reviewed for all selected patients to identify cases of SLE using the 1982 revised American College of Rheumatology criteria. Patients with > or = 4 criteria were classified as definite SLE. Age- and gender-specific SLE incidence rates (1991-2001), the population prevalence rate of SLE on 31 December 2001 and survival rates were calculated. We identified 117 MESA residents with definite SLE. The average age-adjusted incidence of definite SLE was 5.1 per 100 000 per year (95% CI: 3.6, 6.6) and the age-adjusted population prevalence was 78.5 per 100 000 (95% CI: 59.0, 98.0). The mean age at diagnosis among the 44 incident cases was 51.7 years (range: 14-90 years). Positive anti-nuclear antibody (ANA), hematologic abnormalities, arthritis and renal disease were common at diagnosis. Five- and 10-year survival rates were 88% and 76%, respectively. Epidemiologic characteristics of SLE in this rural Caucasian population are generally similar to those reported by other US studies. One notable difference is a relatively high incidence of SLE in older adults.

The fetal environment may be a contributing factor in the etiology of some adult diseases. This study examined whether birth weight, birth length and gestational age are associated with the subsequent development of systemic lupus erythematosus (SLE). The Marshfield Clinic Lupus Registry was searched to identify patients who were born at Saint Joseph's Hospital in Marshfield, Wisconsin, USA. Birth data on each case and five age-, sex-, and race-matched controls were recorded from medical and delivery room register records. Perinatal data were obtained for 23 cases and 115 controls. The unadjusted mean birth weight was similar for cases (3407 +/- 581 g) and controls (3422 +/- 514 g). Birth length was not different between groups. Birth weight adjusted for gestational age, analysed by conditional logistic regression, was not statistically significantly different between groups. We concluded that birth weight and length were similar among SLE cases and controls, suggesting that these perinatal characteristics are not associated with subsequent SLE.

The objective of this study was to obtain estimates of (co)variance components for reproductive traits and insulin-like growth factor-I (IGF-I) concentration. Data were from a divergent selection experiment for blood serum IGF-I concentration in Angus beef cattle. Numbers of observations for mean IGF-I concentration of three blood samples taken at d 28, 42, and 56 of the 140-d postweaning test, scrotal circumference (SC), percentage of motile sperm cells (PMSC), percentage of morphologically normal sperm cells (PNSC), age of heifers at first calving (AFC), and calving rate (CR) were 1,848, 825, 596, 765, 294, and 2,092, respectively. Total number of animals in the numerator relationship matrix, including base animals, was 2,864, of which 1,861 were inbred. Estimates of direct heritability for IGF-I concentration of three blood samples collected at d 28, 42, and 56 of the postweaning test and for mean IGF-I concentration were 0.43+/-0.08, 0.51+/-0.09, 0.41+/-0.08, and 0.50+/-0.08, respectively. Estimates of direct heritability for SC, PMSC, PNSC, AFC, and CR were 0.51+/-0.13, 0.08+/-0.12, 0.47+/-0.07, 0.26+/-0.28, and 0.11+/-0.05, respectively. With the exception of age at first calving, estimates of maternal heritability and proportion of phenotypic variance that were due to permanent environmental effects of the dams were smaller than 0.21. Observations for calving rate were entered as either 1 (if calved) or 100 (if not calved). Estimates of additive genetic correlations of mean IGF-I concentration with SC, PMSC, PNSC, AFC, and CR were 0.35+/-0.11, 0.43+/-0.32, 0.00+/-0.03, -0.14+/-0.33, and -0.41+/-0.16, respectively. Environmental and phenotypic correlations for all of the traits with IGF-I measurements were smaller than 0.23. These results suggest that selection for increased serum IGF-I concentration should result in increased scrotal circumference, percent motile sperm cells, and calving rate.

The Pit-1 gene was studied as a candidate for genetic markers of growth and carcass traits. Angus beef cattle that were divergently selected for high- or low-blood serum IGF-I concentration were used in this study. The single-strand conformation polymorphism method was used to identify polymorphism in the Pit-1 gene including regions from intron 2 to exon 6. Two polymorphisms, Pit1I3H (HinfI) and Pit1I3NL (NlaIII), were detected in intron 3 of the Pit-1 gene. One polymorphism, Pit1I4N (BstNI), was found in intron 4, and a single nucleotide polymorphism, Pit1I5, was found in intron 5. The previously reported polymorphism in exon 6, Pit1E6H (HinfI), was also studied in 416 Angus beef cattle. Associations of the polymorphisms with growth traits, carcass traits, and IGF-I concentration were analyzed using a general linear model procedure. No significant associations were observed between these polymorphisms and growth and carcass traits.

MS-275 is a histone deacetylase (HDAC) inhibitor that has been reported to mediate its cytotoxic effect through generation of reactive oxygen species (ROS) in proliferating hematopoietic cell lines. We examined efficacy of MS-275 in nonproliferating chronic lymphocytic leukemia (CLL) cells from patients. In these cells, MS-275 demonstrated an in vitro LC(50) that was one log lower than for normal mononuclear cells. Following MS-275 treatment, histones H3 and H4 showed increased acetylation and HDAC enzymatic activity was reduced. Caspase-8, -9, and -3 were activated, and caspase substrates PARP and BID were cleaved. Additionally, FLICE-inhibitory protein (FLIP) was downmodulated following MS-275 incubation. MS-275 treatment caused detectable ROS generation after 15 h of incubation, which was blocked by the caspase inhibitor Z-VAD-fmk. Overexpression of Bcl-2 protein protected against MS-275-induced apoptosis. These data demonstrate that MS-275 is a promising therapy for the treatment of CLL, but that in contrast to previous reports, ROS generation does not precede commitment to apoptosis. Similar to many other therapeutic targets, MS-275-mediated apoptosis is reduced by overexpression of Bcl-2, justifying strategies to combine HDAC inhibitors with Bcl-2 antagonists.

Phosphorylated mannans derived from the yeast cell wall of Saccharomyces cerevisiae may beneficially modulate immune function in the weanling pig, possibly providing an alternative to the use of dietary growth-promoting antibiotics. Therefore, in this study, 32 pigs averaging 19 d of age and 5.7 +/- 0.2 kg initial BW were randomly assigned to 16 pens in an environmentally controlled nursery to determine the effects of dietary supplementation with phosphorylated mannans on growth and immune function. Average daily gain and G:F ratio increased (P < 0.05) when pigs were fed diets supplemented with mannans from d 0 to 14 after weaning and in the overall experiment. Percentage of neutrophils was lower (P < 0.08) and percentage of lymphocytes was higher (P < 0.05) in blood from pigs fed mannans than when pigs were fed the basal diet. Lamina propria macrophages isolated from pigs fed diets containing mannans phagocytosed a greater (P < 0.05) number of sheep red blood cells (2.63 +/- 0.11) than did lamina propria macrophages isolated from pigs fed the basal diet (2.31 +/- 0.11). On d 19 after weaning, pigs fed diets supplemented with mannans tended to have a greater (P < 0.10) percentage of CD14+ lamina propria leukocytes than did pigs fed the basal diet. On d 21 following weaning, the percentage of CD14+MHCII+ leukocytes isolated from lamina propria tissue tended (P < 0.10) to be lower when pigs were fed mannans than when pigs were fed the basal diet. Pigs fed diets containing mannans had a lower (P < 0.05) ratio of CD3+CD4+:CD3+CD8+ T lymphocytes isolated from jejunal lamina propria tissue only on d 21 after weaning compared with pigs fed the basal diet. Supplementation of mannans in the diets of weanling pigs improved gain and efficiency, and intermittently affected selected components of the young pigs' immune function both systemically and enterically.

Ammonia (NH3) losses from swine manure contribute to odor problems, decrease animal productivity, and increase the risk of acid rain deposition. This study was conducted to determine whether aluminum chloride (AlCl3) or dietary manipulation with phytase could decrease relative NH3 losses from swine manure. Twenty-four pens of nursery pigs were used in two trials, and the pigs were fed normal or phytase-supplemented (500 IU/kg) diets. Aluminum chloride was added to manure pits (1.9 x 1.2 x 0.5 m) under each pen at 0, 0.25, 0.50, or 0.75% (vol:vol) of final manure volume. Manure pH and NH3 losses (measured by relative NH3 flux) were determined twice weekly. The addition of AlCl3 at 0.75% decreased (P < 0.05) manure pH from 7.48 to 6.69. Phytase decreased (P < 0.05) manure pH to 7.07 compared with 7.12 in the normal diet manure. Aluminum chloride administered at 0.75% without phytase reduced (P < 0.05) relative NH3 losses 52% for the entire 6-wk period. Relative NH3 losses were decreased (P < 0.05) from 109 mg of NH3/(m2 x h) in pens containing pigs fed the normal diet without AlCl3 to 81 mg of NH3/(m2 x h) in pens housing pigs administered the phytase diet, a 26% reduction. When the phytase diet and 0.75% AlCl3 additions were used in combination, relative NH3 losses were reduced (P < 0.05) by 60% compared with pens of pigs fed the control diet without AlCl3. Decreases in manure pH were likely responsible for the observed reduction in NH3 losses. Multiple regression was performed with relative rates of NH3 losses as the dependent variable and rate of AlCl3 addition, diet, and manure pH as independent variables. The model was tested using a stepwise regression (P < 0.001), and results indicated that the most important factors determining NH3 losses were manure pH and diet. However, the contribution of AlCl3 cannot be discounted. When manure pH was regressed against AlCl3 and dietary phytase, AlCl3 levels accounted for 64% of the variation in manure pH (P < 0.001). Dietary manipulation with phytase and application of AlCl3 to manure are promising management practices for the reduction of NH3 from swine facilities.

Three experiments were conducted to evaluate the efficacy of phosphorylated mannans (MAN) and pharmacological levels of ZnO on performance and immunity when added to nursery pig diets. Pigs (216 in each experiment), averaging 19 d of age and 6.2, 4.6, and 5.6 kg of BW in Exp. 1, 2, and 3, respectively, were blocked by BW in each experiment, and penned in groups of six. A lymphocyte blastogenesis assay was performed in each experiment to measure in vitro lymphocyte proliferation response. In Exp. 1, diets were arranged as a 2 x 2 factorial with two levels of Zn (200 and 2,500 ppm) and two levels of MAN (0 and 0.3% from d 0 to 10, and 0 and 0.2% from d 10 to 38). Zinc oxide increased (P < 0.05) ADG, ADFI, and G:F from d 0 to 10, and ADG and ADFI from d 10 to 24. In Exp. 2, diets were arranged as a 2 x 3 factorial with two levels of Zn (200 and 2,500 ppm) and three levels of MAN (0, 0.2, and 0.3%). Pigs fed 2,500 ppm Zn from d 0 to 10 had greater (P < 0.05) ADG, ADFI, and G:F than pigs fed 200 ppm Zn. From d 10 to 24, ADG was similar when pigs were fed 200 ppm Zn, regardless of MAN supplementation; however, ADG increased (P < 0.05) when 0.2% MAN was added to dietscontaining 2,500 ppm Zn (MAN x Zn interaction, P < 0.05). In Exp. 3, diets were arranged as a 2 x 3 factorial with two levels of MAN (0 and 0.3%) and three levels of Zn (200, 500, and 2,500 ppm). Zinc was maintained at 200 ppm from d 21 to 35, so only two dietary treatments (0 and 0.3% MAN) were fed during this period. Average daily gain was greater (P < 0.05) from d 7 to 21 when pigs were fed 2,500 ppm Zn compared with pigs fed 200 or 500 ppm Zn. The addition of MAN improved (P < 0.05) G:F from d 7 to 21 and d 0 to 35. Lymphocyte proliferation of unstimulated cells and phytohemagglutinin-stimulated cells was decreased (P < 0.05) in cells isolated from pigs fed MAN compared with cells isolated from pigs fed diets without MAN. Lymphocyte proliferation of pokeweed mitogen-stimulated cells isolated from pigs fed MAN was less (P < 0.05) than for pigs fed diets devoid of MAN when diets contained 200 ppm Zn; however, MAN had no effect on lymphocyte proliferation when the diet contained 500 or 2,500 ppm Zn (MAN x Zn interaction, P < 0.05). Although the magnitude of response to MAN was not equivalent to that of pharmacological concentrations of Zn, MAN mayimprove growth response when pharmacological Zn levels are restricted.

Non-viral (synthetic) nucleic acid delivery systems have the potential to provide for the practical application of nucleic acid-based therapeutics. We have designed and prepared a tunable, non-viral nucleic acid delivery system that self-assembles with nucleic acids and centers around a new class of polymeric materials; namely, linear, water-soluble cyclodextrin-containing polymers. The relationships between polymer structure and gene delivery are illustrated, and the roles of the cyclodextrin moieties for minimizing toxicity and forming inclusion complexes in the self-assembly processes are highlighted. This vehicle is the first example of a polymer-based gene delivery system formed entirely by self-assembly.

Postweaning serum insulin-like growth factor-I (IGF-I) concentrations and serum IGF binding proteins (IGFBP) were investigated in 68 (1992 Fall-born) and 84 (1999 Fall-born) Angus cattle selected for either high or low serum IGF-I concentrations since 1989. Relative serum levels of IGFBP were determined by [125I]IGF-I Western ligand blotting. IGFBP species of 38-42, 34, 30, and 24 kDa were identified. The 34 kDa species was identified as IGFBP-2 by immunoblot analysis. No significant line effects were observed for any of the IGFBP. In both 1992 and 1999, heifers had higher IGFBP-2 levels than bulls (P<0.0005). In 1992 calves, relative levels of the 38-42 and 24 kDa species were significantly correlated with serum IGF-I concentration. In 1999 calves, none of the IGFBP were correlated with serum IGF-I, although IGFBP-2 was negatively correlated with several measures of body weight. No significant line effects were observed for growth or serum IGF-I traits in 1992 calves. However, 1999 high line calves had higher serum IGF-I concentrations and body weights than low line calves (P<0.05). In both 1992 and 1999 calves, bulls had higher serum IGF-I concentrations and body weights than heifers (P<0.05). Thus, while selection for high versus low serum IGF-I concentrations has resulted in divergence between the selection lines and also in changes in body weights, it has not resulted in changes in serum IGFBP levels. Furthermore, circulating IGFBP-2 appears to be higher in heifers than in bulls, and also appears to be negatively correlated with body weights.

A divergent selection experiment for serum IGF-I concentration began at the Eastern Ohio Resource Development Center in 1989 using 100 spring-calving (50 high line and 50 low line) and 100 fall-calving (50 high line and 50 low line) purebred Angus cows. Following weaning, bull and heifer calves were fed in drylot for a 140-d period. Real-time ultrasound measurements of backfat thickness and longissimus muscle area were taken on d 56 and 140 of the postweaning test. Only ultrasound data from calves born from fall 1995 through spring 1999 were included in the analysis. At the time of this study, IGF-I measurements were available for 1,521 bull and heifer calves, and ultrasound data were available for 636 bull and heifer calves. Data were analyzed by multiple-trait, derivative-free, restricted maximum likelihood methods. Estimates of direct heritability for IGF-I concentration at d 28, 42, and 56 of the postweaning period, and for mean IGF-I concentration were 0.26 +/- 0.07, 0.32 +/- 0.08, 0.26 +/- 0.07, and 0.32 +/- 0.08, respectively. Direct heritabilities for ultrasound estimates of backfat thickness ranged from 0.17 +/- 0.11 to 0.28 +/- 0.12, whereas direct heritabilities for longissimus muscle area ranged from 0.20 +/- 0.10 to 0.36 +/- 0.12, depending on the time of measurement and the covariate used for adjustment (age vs. weight). Direct genetic correlations of IGF-I concentrations with backfat thickness at d 56 and 140 and with longissiumus muscle area at d 56 and 140 averaged 0.02, 0.20, -0.08, and 0.23, respectively, when age was used as the covariate for both IGF-I and ultrasound measurements. Corresponding genetic correlations when age was used as the covariate for IGF-I and weight was used as the covariate for ultrasound measurements were 0.05, -0.07, -0.22, and -0.04, respectively. Therefore, the positive associations of serum IGF-I concentration with backfat thickness and longissimus muscle area at d 140 seem to have been partially mediated by weight. Results of this study do not indicate strong associations of serum IGF-I concentration with fat thickness or muscling of bulls and heifers during the postweaning feedlot period.

This study was conducted to identify polymorphisms in the promoter and coding regions of the bovine growth hormone and growth hormone receptor genes and to study association of polymorphisms identified in these genes with growth traits and serum insulin-like growth factor-I (IGF-I) concentration. The denaturing gradient gel electrophoresis method and sequencing were utilized to identify three new single nucleotide polymorphisms in the promoter region of the growth hormone gene in Angus cattle. Polymerase chain reaction-based restriction fragment length polymorphism procedures were developed for rapid determination of the single nucleotide polymorphism genotypes in the growth hormone and the growth hormone receptor genes among Angus calves from lines divergently selected for high or low blood serum IGF-I concentration. The IGF-I concentration and growth traits were analyzed using animal models. The single nucleotide polymorphism in the promoter region of the growth hormone receptor gene was associated with serum IGF-I concentration on d 42 of the postweaning test and with mean IGF-I concentration. The associated effects of the markers need to be verified in other populations.

Two experiments were conducted to determine the efficacy of mannan oligosaccharides (MOS) fed at two levels of Cu on growth and feed efficiency of weanling and growing-finishing pigs, as well as the effect on the immunocompetence of weanling pigs. In Exp. 1, 216 barrows (6 kg of BW and 18 d of age) were penned in groups of six (9 pens/treatment). Dietary treatments were arranged as a 2 x 2 factorial consisting of two levels of Cu (basal level or 175 ppm supplemental Cu) with and without MOS (0.2%). Diets were fed from d 0 to 38 after weaning. Blood samples were obtained to determine lymphocyte proliferation in vitro. From d 0 to 10, ADG, ADFI, and gain:feed (G:F) increased when MOS was added to diets containing the basal level of Cu, but decreased when MOS was added to diets containing 175 ppm supplemental Cu (interaction, P < 0.01, P < 0.10, and P < 0.05, respectively). Pigs fed diets containing 175 ppm Cu from d 10 to 24 and d 24 to 38 had greater (P < 0.05) ADG and ADFI than those fed the basal level of Cu regardless of MOS addition. Pigs fed diets containing MOS from d 24 to 38 had greater ADG (P < 0.05) and G:F (P < 0.10) than those fed diets devoid of MOS. Lymphocyte proliferation was not altered by dietary treatment. In Exp. 2, 144 pigs were divided into six pigs/pen (six pens/treatment). Dietary treatments were fed throughout the starter (20 to 32 kg BW), grower (32 to 68 kg BW), and finisher (68 to 106 kg BW) phases. Diets consisted of two levels of Cu (basal level or basal diet + 175 ppm in starter and grower diets and 125 ppm in finisher diets) with and without MOS (0.2% in starter, 0.1% in grower, and 0.05% in finisher). Pigs fed supplemental Cu had greater (P < 0.05) ADG and G:F during the starter and grower phases compared to pigs fed the basal level of Cu. During the finisher phase, ADG increased when pigs were fed MOS in diets containing the basal level of Cu, but decreased when MOS was added to diets supplemented with 125 ppm Cu (interaction, P < 0.05). Results from this study indicate the response of weanling pigs fed MOS in phase 1 varied with level of dietary Cu. However, in phase 2 and phase 3, diets containing either MOS or 175 ppm Cu resulted in improved performance. Pharmacological Cu addition improved gain and efficiency during the starter and grower phases in growing-finishing pigs, while ADG response to the addition of MOS during the finisher phase seems to be dependent upon the level of Cu supplementation.

The relationship between estrogen receptor (ESR) genotype and reproductive traits in a population of Yorkshire, Large White, and crossbred animals was studied. Reproductive tract and litter data were analyzed for associations with ESR genotype, parity, and breed. Forty-six Yorkshire, 31 Large White, and 70 crossbred females from the above population were mated to Hampshire boars and slaughtered at 75 d of gestation. Data collected included ovulation rate, uterine horn length, number of fetuses, fetal weight, uterine weight, number of mummies, fetal sex, fetal placement, fetal survival, and fetal space. Data were analyzed using a model that included the fixed effects of ESR genotype, breed, parity, and all significant two-way interactions. Litter data representing 212 litter records were analyzed in a model that included the fixed effects of ESR genotype of dam, parity, farrowing month, dam breed, sire breed, and all significant two-way interactions. The ESR genotype was significantly associated with the total litter weight of piglets born and total litter weight of piglets born alive. Dams with the AA genotype had significantly (P = 0.04) heavier litters at birth (14.44 +/- 0.36 kg) than dams with the BB genotype (13.43 +/- 0.47 kg). Ovulation rate was significantly (P < 0.05) different between animals of parity 1 (17.22 +/- 0.41) and parity > or = 3 (19.92 +/- 0.85). Significant breed effects were observed for fetal weight, with purebred Large White animals having a greater fetal weight per horn (3,909 +/- 114 g) than purebred Yorkshire animals (3,553 +/- 92 g). Notable, but nonsignificant, trends with respect to ESR genotype were also observed for number of piglets alive at weaning and total litter weight at weaning. The ESR gene is positively associated with several previously uninvestigated reproductive traits.

In this study, we defined the signaling cascade responsible for increased eNOS mRNA expression in response to laminar shear stress. This pathway depends on the tyrosine kinase c-Src because shear induction of eNOS mRNA is blocked by the c-Src inhibitors PP1 and PP2, as well as an adenovirus encoding kinase inactive c-Src. After activation of c-Src, this pathway diverges. One arm is responsible for the short-term (6 hour) increase in eNOS mRNA. This involves a transient, 1-hour increase in eNOS transcription, as detected by nuclear run-on, that is dependent on activation of Ras and is blocked by adenoviral infection with dominant negative Ras. Downstream of Ras, MEK1/2 and ERK1/2 are important in this pathway, as 2 inhibitors of MEK1/2, PD98059 and UO126, completely prevented this early increase in eNOS mRNA. ERK1/2 was rapidly phosphorylated in response to shear, and this was prevented by c-Src and Ras inhibition. Further, Raf is phosphorylated in response to shear stress, and this is prevented by c-Src inhibition, suggesting that Raf may transduce the signal between Ras and ERK1/2. The second arm of the pathway linking activation of c-Src to eNOS expression involves stabilization of eNOS mRNA by shear stress. This response to shear is completely abrogated by the c-Src inhibitor PP1 but not altered by Ras or MEK1/2 inhibition. Thus, c-Src plays a central role in modulation of eNOS expression in response to shear stress via divergent pathways involving a short-term increase in eNOS transcription and a longer-term stabilization of eNOS mRNA.

We have recently demonstrated that hydrogen peroxide (H(2)O(2)) is an extremely potent stimulus of endothelial NO synthase (eNOS) gene expression. The present study was designed to identify the signaling mechanisms mediating this response. Induction of eNOS expression by H(2)O(2) was found to be Ca(2+) dependent, inasmuch as it was blocked by BAPTA-AM. Further studies have indicated that Ca(2+)/calmodulin-dependent protein kinase II (CaM kinase II) plays a critical role in mediating this response. Immunocytochemical staining with an anti-CaM kinase II antibody confirmed the expression of CaM kinase II in cultured bovine aortic endothelial cells. H(2)O(2) induced autophosphorylation of CaM kinase II and increased the activity of the enzyme, as assessed by an in-gel kinase assay. A specific inhibitor for CaM kinase II, KN93, and a calmodulin antagonist, W-7, attenuated eNOS induction by H(2)O(2). Further studies have indicated that janus kinase 2 is important in mediating increased eNOS expression in response to H(2)O(2) and likely is downstream from CaM kinase II. In conclusion, these data provide the first evidence that CaM kinase II plays a critical role in endothelial redox signaling. Regulation of eNOS via this pathway may represent an important vascular adaptation to oxidant stress.

A 74-year-old woman with a recent diagnosis of peptic ulcer disease diagnosed by endoscopy after presentation with an episode of upper gastrointestinal bleeding returned 6 1/2 weeks later with a 5-day history of nausea and vomiting without associated symptoms. An ultrasound was nondiagnostic except for a large gallstone and a poorly visualized gallbladder. Repeat endoscopy revealed a hard mass that was presumed to have formed secondarily to an ulcer-induced stricture, and a 6-cm filling defect just proximal to the duodenal bulb was seen on a preoperative upper gastrointestinal series. At laparotomy the mass was actually a large gallstone and two smaller stones, which had eroded into and become impacted in the duodenal bulb creating a gastric outlet obstruction. The stones were extracted via a duodenotomy, and the remaining portion of the gallbladder was removed with repair of the cholecystoduodenal fistula. The patient was discharged home after an uncomplicated postoperative course. Gastric outlet obstruction by a duodenal gallstone is a condition known as Bouveret's syndrome, which is a rare complication of gallstone disease. Upper gastrointestinal hemorrhage is an especially rare form of presentation.

The objective of this research was to evaluate a biallelic genetic marker identified in the first promoter region of the bovine IGF-I gene. The point mutation was identified as a T-to-C transition by sequencing the polymorphic fragments. A PCR-RFLP procedure was developed for determining the marker genotypes. Marker genotypes were determined for 760 Angus calves from divergent lines that were created by selection for high or low serum IGF-I concentration (allele A: 63.9%, B: 36.1%). Data were analyzed using the multiple-trait derivative-free restricted maximum likelihood computer programs with animal models. The full animal model included fixed effects of marker genotype, birth year, season of birth, sex, age of dam, and selection line; random effects of animal, maternal genetic, and maternal permanent environmental effects; and a covariate for age of calf. Traits analyzed included blood serum IGF-I concentrations on d 28, 42, and 56 of the postweaning test, mean IGF-I concentration, birth weight, weaning weight, on-test weight, off-test weight, off-test hip height, postweaning gain, and weight gain during the 20-d period immediately after weaning. Results from the analysis across selection lines showed a significant association of the BB genotype with higher weight gain during the first 20 d after weaning and a slight dominance effect of the marker on postweaning gain. Analysis within the low IGF-I line also showed a significant association of the BB genotype with higher weight gain during the first 20 d after weaning and with on-test weight, although analysis within the high IGF-I line did not show any significant association. The associated effects of the marker need to be verified in other cattle populations.

The synthesis of aluminosilicate zeolite, SSZ-25, is described using a two-component organic guest molecule strategy. This method has been recently described by us and is quite effective in crystallizing a variety of aluminosilicate zeolites with reduction in template cost. In this instance the original organic guest component used in the discovery of SSZ-25, N',N',N'-trimethyl-2-adamantammonium cation, is used in conjunction with a variety of smaller amines. The amine is the major organic component in the synthesis and the quaternary ammonium compound, while a minor component, is essential for structure direction to the desired zeolite product. Studies here show that the adamantyl component is preferentially taken up during crystal growth. Our studies showed that the use of the multi-organic component approach to synthesis resulted in a faster and cheaper route to crystallizing SSZ-25. The SSZ-25 has been described in the literature as having the MWW topology and as such has two different channel systems accessed by 10-ring openings; the channel systems do not intersect. One set of 10-rings open into large cavities. In this study we used NMR spectroscopy to examine the as-made materials and to see if the two organic components are used in different capacities in the synthesis, probing if the admantyl component is only found in these larger cavities. The crystalline products could be affected by solvent extraction with polar solvents like dimethylformamide: the X-ray powder patterns and elemental analyses changed with solvent treatment. The solvent-treated crystals were studied by NMR spectroscopy, elemental analysis, and argon adsorption. The two-component organic guest approach was also found to be quite flexible not only with regard to the amine, but also towards the quaternary ammonium compounds. Non-adamantyl polycyclic templates could be used, and polar but non-quaternized adamantyl derivatives also succeeded in directing towards SSZ-25 formation. On the other hand. in one instance it was shown that the two-component approach favors SSZ-25 as the kinetic product but at longer run times Ostwald ripening was observed, leading to the disappearance of SSZ-25 and formation of ferrierite zeolite and quartz.

Cationic, polymer-based delivery systems have faced limitations in the systemic delivery of therapeutic gene drugs due to difficulties in formulation, in vivo stabilization, toxicity and low transfection efficiencies. Strategies for overcoming some of these barriers have utilized knowledge gained from the fields of colloidal stabilization and protein trafficking. This review highlights recent efforts in polycation preparations that include the development of new polymers for gene delivery, the modification of traditional polycations with hydrophilic polymers for salt and serum stability and the addition of bioactive functionalities to polymers for enhanced intracellular trafficking. These studies have resulted in polymer/DNA composites with increased stability and delivery efficiencies.