RNA interference and functional characterization of a tergal gland alpha amylase in the German cockroach, Blattella germanica L.

German cockroach males possess tergal glands that secrete a combination of oligosaccharides, lipids and proteins. Four major proteins occur in the secretion, with one being the 63 kDa alpha-amylase Blattella germanica Tergal Gland protein-1 (BGTG-1). Denaturing and starch gel electrophoresis coupled with peptide sequencing verified amylase activity for the BGTG-1 protein. BGTG-1 gene expression profiles were determined by using quantitative real-time PCR to compare messenger RNA abundance among isolated tissues of males, females and gravid females. Differences in BGTG-1 gene expression occurred among male tissues, with tergal gland tissue showing the highest expression. Tissues of nongravid and gravid females had significantly lower expression in comparison with male tergal glands (gravid females lowest). RNA interference (RNAi) was used to silence BGTG-1 gene expression by injecting BGTG-1 homologous double-stranded RNA (dsRNA) into male cockroaches. Groups injected with BGTG-1 dsRNA showed ∼90% lower BGTG-1 gene and protein expression compared to controls, which correlated with lower amylase activity in colorimetric assays. However, behavioural assays comparing precopulatory behaviour and mating success between RNAi and control males did not reveal differences. These results connect amylase gene expression and activity in tergal gland tissue but suggest other factors, such as other tergal gland components, may contribute more strongly to mating success.

The effects of porcine intestinal mucosa protein sources on nursery pig growth performance.

Three studies were conducted to compare the effects of 4 different porcine intestinal mucosa products (PEP2, PEP2+, Peptone 50, and PEP-NS; TechMix Inc., Stewart, MN) with select menhaden fish meal (SMFM) on nursery pig performance. These intestine-derived mucosal ingredients are byproducts of heparin production, with a similar amount of mucosal protein, but differ based on the carriers with which they are co-dried. Enzymatically processed vegetable protein is the carrier for PEP2 whereas PEP2+ is co-dried with enzymatically processed vegetable proteins and biomass from crystalline AA production. Peptone 50 uses vegetable protein as its carrier while PEP-NS is co-dried with byproducts of corn wet milling and biomass from crystalline AA production. In Exp. 1, 300 weanling pigs (PIC 327 × 1050; initially 5.4 kg and 19 d of age) were allotted to 1 of 5 dietary treatments with 12 replications and 5 pigs per pen. Diets consisted of a negative control (NC) containing no specialty protein sources, NC with 4, 8, or 12% PEP2 in phases 1 (d 0 to 11) and 2 (d 11 to 25), and a positive control containing 4% spray-dried animal plasma (SDAP) in phase 1 and 4% SMFM in phase 2. From d 0 to 11, pigs fed SDAP had greater (P < 0.05) ADG and G:F than pigs fed PEP2. From d 11 to 25, increasing PEP2 increased (quadratic; P < 0.01) ADG and G:F, with the greatest response observed at 4%. In Exp. 2, 960 weanling pigs (Newsham GPK35 × PIC 380; initially 5.6 kg, and 20 d of age) were allotted to 1 of 5 dietary treatments with 32 pigs per pen and 6 replications per treatment. Diets included a control with 4.5% SDAP in phase 1 (d 0 to 7) and no specialty protein sources in phase 2 (d 7 to 21) or the control diet with 6% of the following: SMFM, PEP2+, Peptone 50, or PEP-NS. From d 0 to 21, pigs fed diets containing SMFM, PEP2+, or PEP-NS had greater (P < 0.05) ADG than pigs fed the control or 6% Peptone 50. In Exp. 3, 180 nursery pigs (PIC 327 × 1050; initially 6.4 kg and 28 d of age) were allotted to 1 of 5 dietary treatments with 5 pigs per pen and 6 replications per treatment. Treatment diets were fed from d 7 to 21 postweaning. Treatments consisted of a NC, NC with 3, 6, 9, or 12% PEP-NS, or NC with 6% SMFM. Overall, pigs fed increasing PEP-NS had improved (quadratic; P < 0.01) ADG and G:F, with the greatest improvement observed in pigs fed 6% PEP-NS, similar to those fed 6% SMFM. These results suggest PEP2, PEP2+, and PEP-NS can effectively replace SMFM in nursery pig diets.

Evaluation of two mycotoxin mitigation strategies in grow-finish swine diets containing corn dried distillers grains with solubles naturally contaminated with deoxynivalenol.

A total of 1,040 growing pigs (initially, 22.9 ± 4.3 kg) were used in a 115-d study to evaluate the effects of 2 mycotoxin mitigation strategies, a preservative blend (PB) and a yeast product (YP), on the growth performance of swine fed diets containing corn dried distillers grains with solubles naturally contaminated with deoxynivalenol (DON). The PB consists of preservatives, antioxidants, AA, and direct-fed microbials and is included in diets to help pigs cope with the toxic effects of ingested mycotoxins. The YP works as an adsorbent to bind and prevent the absorption of mycotoxins in the gastrointestinal tract. Pigs were allotted to pens by initial BW and sex; pens were then assigned to treatments in a randomized block design with initial BW and sex serving as the blocking factors. Pens were randomly allotted to 1 of 4 dietary treatments consisting of a positive control (PC) containing <1 mg kg(-1) DON, a negative control (NC) formulated to contain 4 mg kg(-1) DON, NC with PB, and NC with YP. From d 0 to 42 and 42 to 84, no effect of diets containing PB or YP were observed for any of the growth criteria evaluated. From d 84 to 115, pigs fed PC or diets containing PB had improved (P < 0.05) ADG compared to pigs fed NC or diets containing YP, whereas pigs fed YP had improved (P < 0.05) ADG compared to those fed NC. Pigs fed diets containing PB or YP had improved (P < 0.05) ADFI and G:F compared to pigs fed NC. Overall (d 0 to 115), pigs fed diets containing PB had improved (P < 0.05) ADG, ADFI, and G:F compared to pigs fed NC. These results indicate that PB may be a suitable mycotoxin mitigation strategy in growing swine fed diets naturally contaminated with DON.

The effects of diet form and feeder design on the growth performance of finishing pigs.

Two studies were conducted to determine the effects of diet form (meal vs. pellet) and feeder design (conventional dry vs. wet/dry) on finisher pig performance. Experiments were arranged as 2 × 2 factorials with 11 replications per treatment and 26 to 29 pigs per pen. In Exp. 1, pigs (n = 1,290; initial BW 46.8 kg) were used in a 91-d study. Pelleted diets averaged approximately 35% fines throughout the study. Overall, pigs fed pelleted diets or via wet/dry feeders had greater (P < 0.07 and 0.001, respectively) ADG than pigs fed meal diets or fed with a dry feeder. Diet form × feeder interactions (P < 0.02) were observed for G:F. Pigs fed either meal or pelleted diets via a wet/dry feeder had similar G:F, but pigs fed pelleted diets in dry feeders had poorer G:F than pigs with meal diets in dry feeders. In Exp. 2, pigs (n = 1,146; initial BW 38.2 kg) were used in a 104-d study. From d 0 to 28, a diet form × feeder design interaction (P < 0.01) was observed for ADG, which was due to decreased ADG in pigs fed pelleted diets from a conventional dry feeder compared with pigs fed meal diets from the same feeder type whereas there was no difference in wet/dry feeders based on diet form. Pigs fed pelleted diets had poorer (P < 0.01) G:F than pigs fed meal diets. This result appeared to be due to poor pellet quality (39.6% fines). From d 42 to 86, pellet quality improved (4.4% fines) and a diet form × feeder interaction was observed for ADG in which pigs fed meal diets in a dry feeder had decreased (P < 0.05) ADG than pigs fed pelleted diets in dry feeders or pigs presented either diet in wet/dry feeders. Pigs fed pelleted diets had improved (P < 0.001) G:F. Pigs fed via wet/dry feeders had increased (P < 0.03) ADFI and G:F compared with pigs fed via dry feeders. Overall, pigs fed with wet/dry feeders had increased (P < 0.02) ADG and ADFI and poorer G:F than pigs with dry feeders whereas pigs given pelleted diets had improved (P = 0.05) G:F compared with pigs presented meal diets. These studies found that pigs fed from wet/dry feeders had increased ADG and ADFI compared with pigs fed via dry feeders regardless of diet form. Additionally, pellet quality appeared to influence responses because pigs fed high-quality pellets via dry feeders had better growth performance than pigs fed meal diets. Conversely, if pellet quality was poor, the feed efficiency benefits associated with pelleting were lost.

The effects of feeder adjustment and trough space on growth performance of finishing pigs.

Two studies were conducted to determine the effects of feeder adjustment and trough space on growth performance of finishing pigs. In Exp. 1, 234 pigs (initial BW 41.5 kg) were used in an 89-d trial. Pigs were randomly allotted to 1 of 3 treatments with 9 replications of 8 pigs/pen and 1 replicate with 6 pigs/pen. Treatments consisted of a minimum feeder gap setting of 1.27, 1.91, or 2.54 cm. Feeders were adjusted to a minimum gap setting, but the agitation plate could be moved upward to a maximum opening of 1.91, 2.54, or 3.18 cm, respectively. Feeder adjustments of 1.27, 1.91, and 2.54 cm averaged 28, 58, and 75% pan coverage, respectively. From d 0 to 58, increasing feeder gap improved (linear; P ≤ 0.04) ADG and ADFI, but decreased (linear; P < 0.05) G:F. Although the response was linear for ADG, no increase occurred (quadratic; P = 0.15) beyond the 1.91-cm feeder gap setting. From d 58 to 89, increasing feeder gap setting tended (linear; P = 0.08) to worsen G:F. Overall (d 0 to 89), pigs fed with increasing feeder gap had decreased (linear; P <0.03) G:F due to increased (linear; P <0.02) ADFI. In Exp. 2, 288 pigs (initial BW 41.3 kg) were used in a 91-d study to evaluate the effects of feeder trough space (4.45 vs. 8.9 cm/pig) and minimum feeder gap opening of 1.27 cm (narrow) vs. 2.54 cm (wide). The treatments were arranged in a 2 × 2 factorial with 6 replications per treatment. Feeder trough space was altered by having pens of either 8 to 16 pigs per pen with all pigs provided 0.74 m(2) floor space per pig. From d 0 to 56 and 56 to 91, no adjustment × space interactions or effects of trough space were observed. From d 0 to 56, pigs with the wide feeder gap setting had decreased (P < 0.02) G:F compared with those that had the narrow feeder gap setting. From d 56 to 91, pigs with the wider feeder gap setting had increased (P < 0.001) ADFI, but consequently had decreased (P < 0.01) G:F. Overall (d 0 to 91), no trough space × feeder adjustment interactions were observed. However, ADG tended to increase (P = 0.08) as feeder trough space increased from 4.45 to 8.9 cm/pig. Pigs fed with the wide feeder gap setting had increased (P < 0.01) feed disappearance and decreased (P < 0.01) G:F compared with pigs with the narrow feeder gap setting. These data indicate that pigs from 41 to 68 kg need approximately 58% pan coverage, whereas pigs greater than 68 kg should have approximately 28% pan coverage to optimize growth and reduce feed wastage.

Contribution of lean, fat, muscle color and degree of doneness to pork and beef species flavor.

Flavor is an important contributor to consumer acceptability of meat, our objective was to characterize the impact of species-specific fat/lean sources, fat level, degree of doneness and muscle color are on pork and beef flavor. Three separate experiments were conducted. Patties were formulated differently for each experiment in order to evaluate the desired variables. Experiment. 1: Flavor from combination patties (same species lean/fat or combination of species lean/fat) was not impacted by degree of doneness (66°C vs. 71°C). Beef flavor was highest in samples made with beef lean, regardless of species fat type. Pork flavor was highest in samples made with pork lean and had higher flavor intensity scores. Experiment. 2: Beef flavor was not increased in all-beef patties formulated with higher fat levels. Pork patties formulated with higher fat content increased pork flavor. Experiment. 3: All-beef and all-pork patties formulated with light or dark lean did not impact flavor in either species.

Carcass, meat quality, and sensory characteristics of heavy body weight pigs fed ractopamine hydrochloride (Paylean).

Carcass characteristics, meat quality traits, and sensory attributes were evaluated in late-finishing barrows and gilts, weighing between 100 to 130 kg of BW, fed 0, 5, or 7.4 mg/kg of ractopamine hydrochloride (RAC) for the final 21 to 28 d before slaughter. Carcass data were collected from carcasses from barrows and gilts (n = 168), and all primal cuts from the right sides of these carcasses were fabricated to calculate primal yields as a percentage of the HCW. Subjective (National Pork Producers Council and Japanese) color, firmness, and marbling scores were determined on the LM of each loin and the semimembranosus muscle (SM) of the ham, whereas the moisture, extractable lipid, Warner-Bratzler shear force (WBSF), and trained sensory evaluations (juiciness, tenderness, and pork flavor) were measured on the LM samples only. Gilts produced heavier (P < 0.05) HCW than barrows, whereas feeding RAC increased (P < 0.05) HCW over pigs fed diets devoid of RAC. Carcasses from gilts also had greater (P < 0.02) primal cut and lean cut (P < 0.01) yields than barrows, and dietary inclusion of 5 mg/kg of RAC increased (P < 0.05) total boneless cut and lean cut yields when compared with carcass from pigs fed 0 or 7.4 mg/kg of RAC. Warner-Bratzler shear forces values were greater (P < 0.05) in the LM of gilts than barrows, but only juiciness scores were greater (P < 0.03) in LM chops from barrows than gilts. The LM from barrows had greater intramuscular lipid (P < 0.001) than the LM from gilts, and even though the LM from pigs fed 5 mg/kg of RAC had greater (P < 0.04) WBSF values than the LM from pigs fed 0 or 7.4 mg/kg of RAC, including RAC in the late-finishing diets for 21 or 28 d did not affect sensory panel rating or percentages of moisture and intramuscular lipid. In summary, addition of RAC in the late-finishing diet improved carcass and primal cut yields when it was fed at 5 and 7.4 mg/kg without altering pork quality traits regardless of whether RAC was fed for 21 or 28 d.

Identification of a novel valosin-containing protein polymorphism in late-onset Alzheimer's disease.

BACKGROUND/AIMS: Recently, mutations in the valosin-containing protein gene (VCP) were found to be causative for a rare form of dementia [Watts GDJ, et al.: Nat Genet 2004;36:377-381]. This gene lies within a region on the genome that has been linked to late onset Alzheimer's disease (LOAD) [Myers A, et al.: Am J Med Genet 2002;114:233-242]. In this study, we investigated whether variation within VCP could account for the LOAD linkage peak on chromosome 9. METHODS: We sequenced 188 individuals from the set of sibling pairs we had used to obtain the linkage results for chromosome 9 to look for novel polymorphisms that could explain the linkage signal. Any variant that was found was then typed in 2 additional sets of neuropathologically confirmed samples to look for associations with Alzheimer's disease. RESULTS: We found 2 variants when we sequenced VCP. One was a novel rare variant (R92H) and the other is already reported within the publicly available databases (rs10972300). Neither explained the chromosome 9 linkage signal for LOAD. CONCLUSIONS: We have found a novel rare variant within the VCP gene, but we did not find a variant that could explain the linkage signal for LOAD on chromosome 9.

The H1c haplotype at the MAPT locus is associated with Alzheimer's disease.

Although it is clear that microtubule associated protein tau (MAPT) is involved in Alzheimer's disease (AD) pathology, it has not been clear whether it is involved genetically. We have recently examined the MAPT locus in progressive supranuclear palsy and found that a haplotype (H1c) on the background of the well-described H1 clade is associated with PSP. Here we report that the same haplotype is associated with the risk of AD in two autopsy confirmed series of cases with ages at death >65 years.

Linkage disequilibrium fine mapping and haplotype association analysis of the tau gene in progressive supranuclear palsy and corticobasal degeneration.

BACKGROUND: The haplotype H1 of the tau gene, MAPT, is highly associated with progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD). OBJECTIVE: To investigate the pathogenic basis of this association. METHODS: Detailed linkage disequilibrium and common haplotype structure of MAPT were examined in 27 CEPH trios using validated HapMap genotype data for 24 single nucleotide polymorphisms (SNPs) spanning MAPT. RESULTS: Multiple variants of the H1 haplotype were resolved, reflecting a far greater diversity of MAPT than can be explained by the H1 and H2 clades alone. Based on this, six haplotype tagging SNPs (htSNPs) that capture 95% of the common haplotype diversity were used to genotype well characterised PSP and CBD case-control cohorts. In addition to strong association with PSP and CBD of individual SNPs, two common haplotypes derived from these htSNPs were identified that are highly associated with PSP: the sole H2 derived haplotype was underrepresented and one of the common H1 derived haplotypes was highly associated, with a similar trend observed in CBD. There were powerful and highly significant associations with PSP and CBD of haplotypes formed by three H1 specific SNPs. This made it possible to define a candidate region of at least approximately 56 kb, spanning sequences from upstream of MAPT exon 1 to intron 9. On the H1 haplotype background, these could harbour the pathogenic variants. CONCLUSIONS: The findings support the pathological evidence that underlying variations in MAPT could contribute to disease pathogenesis by subtle effects on gene expression and/or splicing. They also form the basis for the investigation of the possible genetic role of MAPT in Parkinson's disease and other tauopathies, including Alzheimer's disease.

A randomised controlled trial of cytological surveillance versus patient choice between surveillance and colposcopy in managing mildly abnormal cervical smears.

OBJECTIVE: To determine whether choice of colposcopy or six month cytological surveillance would be beneficial to women with mildly abnormal smears when compared with the national policy of six months surveillance in terms of psychological morbidity. DESIGN: A randomised trial based on the Zelen design. SETTING: A hospital-based research clinic. POPULATION: Four hundred and seventy-six women who had had a recurrent borderline or mildly dyskaryotic smear on routine cervical screening in primary care. METHODS: Women were randomised either to six months cytological surveillance or to make a choice between that or colposcopy and were followed up for 1 year. MAIN OUTCOME MEASURES: The primary outcome measure was caseness (score >or=4) on the General Health Questionnaire at 12 months follow up. Other measures were the Spielberger State and Trait scores, default rates and cytology/colposcopy outcomes. RESULTS: There was no significant difference between the arms for General Health Questionnaire (GHQ) scores and Spielberger State and Trait at 12 months. There was a significant reduction in psychometric morbidity between baseline and 12 months in both arms. Overall rates of default from the protocol were the same in both arms, but default that led to uncertain ascertainment of cervical pathology was greater in the no-choice arm. CONCLUSIONS: This trial indicates that having choice did not impact favourably or harmfully on anxiety or feelings of wellbeing. If a patient is anxious, allowing the patient to choose immediate colposcopy may be preferable because it will improve ascertainment of underlying disease in a group who are more likely to default.

The genetics of late-onset Alzheimer's disease.

Of late-onset Alzheimer's disease patients 50% do not carry an apolipoprotein E epsilon 4 allele, indicating that there must be other genetic or environmental risk factors for the disease. During the past few years, both genetic linkage and candidate gene studies have been undertaken in order to identify novel genetic risk factors for late-onset Alzheimer's disease. Previous genome screens implicated a region of chromosome 12 that contains the genes that encode both alpha(2)-macroglobulin and the low-density lipoprotein receptor-related protein. However, candidate gene studies have produced mixed results with respect to both of these genes. New linkage studies now provide strong evidence for Alzheimer's disease susceptibility loci on chromosomes 9 and 10. The locus on chromosome 10 very probably modifies risk for Alzheimer's disease by modulating beta-amyloid-42 levels.

Dopamine D2 receptor bands in normal human temporal cortex are absent in Alzheimer's disease.

A modular organization of bands enriched in high concentrations of D2 receptors are observed throughout the rostral to caudal aspects of the temporal cortex of the normal human at postmortem, but are most frequently observed in the inferior and superior temporal cortices [S. Goldsmith, J.N. Joyce, Dopamine D2 receptors are organized in bands in normal human temporal cortex, Neuroscience 74 (1996) 435-451]. In the tissue derived at postmortem from Alzheimer's disease cases (AD), these D2 receptor-enriched modules were found to be largely absent at rostral and mid-levels of the temporal cortex. Regions exhibiting this loss of receptor binding also showed a marked reduction in the number of pyramidal neurons stained for D2 mRNA. In addition, the AD material exhibited numerous thioflavin-positive plaques and tangle-filled extraneuronal (ghost) pyramidal neurons that were D2 mRNA-negative. Regions that are the earliest affected and most susceptible to classical AD pathology are also most sensitive to the loss of D2 receptors. These results, along with our previous data [J.N. Joyce, C. Kaeger, H. Ryoo, S. Goldsmith, Dopamine D2 receptors in the hippocampus and amygdala in Alzheimer's disease, Neurosci. Lett. 154 (1993) 171-174; H. Ryoo, J. N. Joyce, The loss of dopamine D2 receptors varies along the rostrocaudal axis of the hippocampal complex in Alzheimer's disease, J. Comp. Neurol. 348 (1994) 94-110], indicate that specific pathways enriched with D2 receptors, including that within modules of higher order association cortices of the temporal lobe and continued through segregated pathways within the parahippocampus and hippocampus, are particularly susceptible to the loss in AD. These dopamine D2 receptor-enriched modules may play an important role in the reciprocal activity of large groups of neurons in these high-order association cortical regions. Hence, the loss of the D2 receptor-enriched modules in Alzheimer's disease contributes to disturbances in information processing in these high-order association cortices, and may promote the cognitive and non-cognitive impairments observed in Alzheimer's disease.