bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of heparan sulphate proteoglycans in angiogenesis
Authors: Stringer S.E.
Published: May 2006

The presence of HS (heparan sulphate) proteoglycans on the cell surface and in the extracellular environment is critical to many physiological processes including the growth of new blood vessels from pre-existing vasculature (angiogenesis). A plethora of growth factors and their receptors, extracellular matrix molecules and enzymes bind to specific sites on the HS sugar chain. For example, HS proteoglycans have profound effects on the bioactivity of the key angiogenic factor VEGF (vascular endothelial growth factor) (VEGF165), affecting its diffusion, half-life and interaction with its tyrosine kinase receptors. A number of HS structural features that mediate the specific binding of VEGF165, including sulphation requirements, have been determined. In parallel, zebrafish embryos were used as a vertebrate model system to study the role in vascular development of the biosynthetic enzymes that create these specific binding sites on HS. It was discovered that knockdown of one of the HS 6-O-sulphotransferases in zebrafish with morpholino antisense oligonucleotides reduced vascular branching and corresponded to changes in the HS structure. The roles of the extracellular 6-O-sulphatase enzymes, the sulfs, in vascular development are now being investigated. Both oligosaccharides and small molecule biosynthetic enzyme inhibitors could be valuable HS-based strategies for controlling aberrant angiogenesis in diseases as diverse as cancer and heart disease.
Heparin/heparan sulphate binding in the TGF-β cytokine superfamily
Authors: Rider C.C.
Published: May 2006

The TGF-β (transforming growth factor-β) cytokine superfamily in mammals contains some 30 members. These dimeric proteins are characterized by a strongly conserved cystine knot-based structure. They regulate the proliferation, differentiation and migration of many cell types, and therefore have important roles in morphogenesis, organogenesis, tissue maintenance and wound healing. Thus far, around one-quarter of these cytokines have been shown to bind to heparin and heparan sulphate. Well-established examples are the TGF-β isoforms 1 and 2, and the BMPs (bone morphogenetic proteins) -2 and -4. In studies in my laboratory, we have shown that GDNF (glial-cell-line-derived neurotrophic factor) and its close relatives neurturin and artemin bind to heparin and heparan sulphate with high affinity. We have reported previously that binding of GDNF is highly dependent on the presence of 2-O-sulphate groups. More recently, we and others have been investigating the heparin/heparan sulphate-binding properties of BMP-7, which is a representative of a distinct BMP subgroup from that of BMPs -2 and -4. Interestingly, several of the various specific BMP antagonist proteins also bind to heparin and heparan sulphate. Much remains to be learnt about the nature and role of glycosaminoglycan interactions in the TGF-β superfamily, but current work suggests that these cytokines do not share a single highly conserved heparin/heparan sulphate-binding site.
Liquid water simulation: A critical examination of cutoff length
Authors: Yonetani Yoshiteru
Published: May 2006

Cutoff treatment is the simplest approach for evaluating intermolecular interactions in molecular dynamics simulations. It has been believed that increasing cutoff length makes simulation results better. On the contrary, our results of the bulk water simulations studied within the range of cutoff lengths, 9–18Å, showed an opposite tendency: the artifact was enhanced by increasing the cutoff length. Especially, in terms of the distance dependent Kirkwood factor GK(r), it was clearly shown that the orientational behavior of water molecules becomes gradually worse as the cutoff length becomes longer. The artifact enhanced by the increased cutoff length led to a reported spurious artifact, i.e., phase transition [Y. Yonetani, Chem. Phys. Lett. 406, 49 (2005)]. Though the cutoff artifact was largely reduced by adopting a force switching technique, it did not completely remove the anomalous cutoff length dependence of the artifact. These results suggest that increasing the cutoff should not be attempted regardless of whether the switching force is adopted or not.
A quantum-classical bracket that satisfies the Jacobi identity
Authors: Prezhdo Oleg V.
Published: May 2006

A quantum-classical bracket is proposed and is shown to satisfy the Jacobi identity, in contrast to previous definitions that obey this property only up to higher order terms in the Planck constant ℏ. The Jacobi identity is required of a true Lie bracket and ensures that the Lie bracket of constants of motion is also a constant of motion. An explicit calculation of the Jacobi identity highlights the difference between the proposed and traditional definitions. A further example illustrates that the proposed bracket generates a more consistent quantum-classical dynamics than the traditional bracket. The traditional quantum-classical dynamics in the Henon-Heiles system diverges due to higher order ℏ terms. The divergence is eliminated with the proposed bracket.
Resonantly enhanced multiphoton ionization and zero kinetic energy photoelectron spectroscopy of 2-indanol conformers
Authors: He Yonggang , Kong Wei
Published: May 2006

We report studies of a supersonically cooled 2-indanol using two-color resonantly enhanced multiphoton ionization (REMPI) and two-color zero kinetic energy (ZEKE) photoelectron spectroscopy. In the REMPI experiment, we have identified three conformers of 2-indanol and assigned the vibrational structures of the first electronically excited state for the two major conformers. Conformer Ia contains an intramolecular hydrogen bond between the –OH group and the phenyl ring, while conformer IIb has the –OH group in the equatorial position. We have further investigated the vibrational spectroscopy of the cation for the two major conformers using the ZEKE spectroscopy. The two conformers display dramatically different vibrational distributions. The ZEKE spectrum of conformer Ia shows an extensive progression in the puckering mode of the five member ring, indicating a significant geometry change upon ionization. The ZEKE spectra of conformer IIb are dominated by single vibronic transitions, and the intensity of the ZEKE signal is much stronger than that of conformer Ia. These results indicate an invariance of the molecular frame during ionization for conformer IIb. We have performed ab initio and density functional theory calculations to obtain potential energy surfaces along the dihedral angle involving the –OH group for all three electronic states. In addition, we have also calculated the vibrational distribution of the ZEKE spectrum for the puckering mode of the five member ring. Not only the vibrational frequencies but also the intensity distributions for both conformers have been reproduced satisfactorily. The adiabatic ionization energies have been determined to be 68593±5cm−1 for conformer Ia and 68981±5cm−1 for conformer IIb.
Observation of a simple vibrational wavepacket in a polyatomic molecule via time-resolved photoelectron velocity-map imaging: A prototype for time-resolved IVR studies
Authors: Hammond Chris J. , Reid Katharine L. , Ronayne Kate L.
Published: May 2006

We have prepared a coherent superposition of the two components of a Fermi resonance in the S1 state of toluene at ∼460cm−1 with a ∼1ps laser pulse and monitored time-resolved photoelectron velocity-map images. The photoelectron intensities oscillate with time in a manner that depends on their kinetic energy, even though full vibrational resolution in the cation is not achieved. Analysis of the time-dependent photoelectron spectra enables information on the composition of the S1 wavepacket to be deduced. Such an experiment, in which a whole set of partially dispersed cation vibrational states are detected simultaneously, suggests an efficient method of studying intramolecular vibrational energy redistribution processes in excited states.
Differential regulation of metabolic, neuroendocrine, and immune function by leptin in humans
Authors: Chan Jean L. , Matarese Giuseppe , Shetty Greeshma K. , Raciti Patricia , Kelesidis Iosif , Aufiero Daniela , De Rosa Veronica , Perna Francesco , Fontana Silvia , Mantzoros Christos S.
Published: May 2006

To elucidate whether the role of leptin in regulating neuroendocrine and immune function during short-term starvation in healthy humans is permissive, i.e., occurs only when circulating leptin levels are below a critical threshold level, we studied seven normal-weight women during a normoleptinemic-fed state and two states of relative hypoleptinemia induced by 72-h fasting during which we administered either placebo or recombinant methionyl human leptin (r-metHuLeptin) in replacement doses. Fasting for 72 h decreased leptin levels by ≈80% from a midphysiologic (14.7 ± 2.6 ng/ml) to a low-physiologic (2.8 ± 0.3 ng/ml) level. Administration of r-metHuLeptin during fasting fully restored leptin to physiologic levels (28.8 ± 2.0 ng/ml) and reversed the fasting-associated decrease in overnight luteinizing hormone pulse frequency but had no effect on fasting-induced changes in thyroid-stimulating hormone pulsatility, thyroid and IGF-1 hormone levels, hypothalamic–pituitary–adrenal and renin–aldosterone activity. FSH and sex steroid levels were not altered. Short-term reduction of leptin levels decreased the number of circulating cells of the adaptive immune response, but r-metHuLeptin did not have major effects on their number or
in vitro
function. Thus, changes of leptin levels within the physiologic range have no major physiologic effects in leptin-replete humans. Studies involving more severe and/or chronic leptin deficiency are needed to precisely define the lower limit of normal leptin levels for each of leptin’s physiologic targets.
Stochastic models for regulatory networks of the genetic toggle switch
Authors: Tian Tianhai , Burrage Kevin
Published: May 2006

Bistability arises within a wide range of biological systems from the λ phage switch in bacteria to cellular signal transduction pathways in mammalian cells. Changes in regulatory mechanisms may result in genetic switching in a bistable system. Recently, more and more experimental evidence in the form of bimodal population distributions indicates that noise plays a very important role in the switching of bistable systems. Although deterministic models have been used for studying the existence of bistability properties under various system conditions, these models cannot realize cell-to-cell fluctuations in genetic switching. However, there is a lag in the development of stochastic models for studying the impact of noise in bistable systems because of the lack of detailed knowledge of biochemical reactions, kinetic rates, and molecular numbers. In this work, we develop a previously undescribed general technique for developing quantitative stochastic models for large-scale genetic regulatory networks by introducing Poisson random variables into deterministic models described by ordinary differential equations. Two stochastic models have been proposed for the genetic toggle switch interfaced with either the SOS signaling pathway or a quorum-sensing signaling pathway, and we have successfully realized experimental results showing bimodal population distributions. Because the introduced stochastic models are based on widely used ordinary differential equation models, the success of this work suggests that this approach is a very promising one for studying noise in large-scale genetic regulatory networks.
Hepatocyte nuclear factor 4α orchestrates expression of cell adhesion proteins during the epithelial transformation of the developing liver
Authors: Battle Michele A. , Konopka Genevieve , Parviz Fereshteh , Gaggl Alexandra Lerch , Yang Chuhu , Sladek Frances M. , Duncan Stephen A.
Published: May 2006

Epithelial formation is a central facet of organogenesis that relies on intercellular junction assembly to create functionally distinct apical and basal cell surfaces. How this process is regulated during embryonic development remains obscure. Previous studies using conditional knockout mice have shown that loss of hepatocyte nuclear factor 4α (HNF4α) blocks the epithelial transformation of the fetal liver, suggesting that HNF4α is a central regulator of epithelial morphogenesis. Although HNF4α-null hepatocytes do not express E-cadherin (also called CDH1), we show here that
E-cadherin
is dispensable for liver development, implying that HNF4α regulates additional aspects of epithelial formation. Microarray and molecular analyses reveal that HNF4α regulates the developmental expression of a myriad of proteins required for cell junction assembly and adhesion. Our findings define a fundamental mechanism through which generation of tissue epithelia during development is coordinated with the onset of organ function.
Evidence of hollow golden cages
Authors: Bulusu Satya , Li Xi , Wang Lai-Sheng , Zeng Xiao Cheng
Published: May 2006

The fullerenes are the first “free-standing” elemental hollow cages identified by spectroscopy experiments and synthesized in the bulk. Here, we report experimental and theoretical evidence of hollow cages consisting of pure metal atoms, Au

n

−
(
n
= 16–18); to our knowledge, free-standing metal hollow cages have not been previously detected in the laboratory. These hollow golden cages (“bucky gold”) have an average diameter >5.5 Å, which can easily accommodate one guest atom inside.
Distinct metastable atmospheric regimes despite nearly Gaussian statistics: A paradigm model
Authors: Majda Andrew J. , Franzke Christian L. , Fischer Alexander , Crommelin Daniel T.
Published: May 2006

A controversial topic in the recent climate modeling literature is the fashion in which metastable low-frequency regimes in the atmosphere occur despite nearly Gaussian statistics for these planetary waves. Here a simple 57-mode paradigm model for such metastable atmospheric regime behavior is introduced and analyzed through hidden Markov model (HMM) analysis of the time series of suitable low-frequency planetary waves. The analysis of this paradigm model elucidates how statistically significant metastable regime transitions between blocked and zonal statistical states occur despite nearly Gaussian behavior in the associated probability distribution function and without a significant role for the low-order truncated nonlinear dynamics alone; turbulent backscatter onto the three-dimensional subspace of low-frequency modes is responsible for these effects. It also is demonstrated that suitable stochastic mode reduction strategies, which include both augmented cubic nonlinearity and multiplicative noise, are also capable of capturing the metastable low-frequency regime behavior through a single stochastic differential equation compared with the full turbulent chaotic 57-mode model. This feature is attractive for issues such as long-term weather predictability. Although there have been many applications of HMM in other sciences, this work presents a previously undescribed application of HMM analysis to atmospheric low-frequency variability and points the way for further applications including their use in extended range predictability.
Essential role of mda-5 in type I IFN responses to polyriboinosinic:polyribocytidylic acid and encephalomyocarditis picornavirus
Authors: Gitlin Leonid , Barchet Winfried , Gilfillan Susan , Cella Marina , Beutler Bruce , Flavell Richard A. , Diamond Michael S. , Colonna Marco
Published: May 2006

The innate immune system recognizes viral dsRNA through two distinct pathways; the Toll-like receptor 3 (TLR3) pathway detects dsRNA phagocytosed in endosomes; the helicases retinoic acid-induced protein I (RIG-I) and melanoma differentiation-associated gene-5 (mda-5) detect cytoplasmic dsRNA generated during viral replication. Both RIG-I and mda-5 can bind polyriboinosinic:polyribocytidylic acid (polyI:C), the synthetic analog of viral dsRNA, and mediate type I IFN responses to polyI:C and multiple RNA viruses
in vitro
. We generated mda-5-deficient mice and showed that mda-5 is the dominant receptor mediating type I IFN secretion in response to polyI:C
in vitro
and
in vivo
. Moreover, mda-5−/− mice exhibited a selectively impaired antiviral response to encephalomyocarditis picornavirus, indicating functional specialization of mda-5
in vivo
.
The effect of lactose and inulin on intestinal morphology, selected microbial populations and volatile fatty acid concentrations in the gastro-intestinal tract of the weanling pig
Authors: Pierce K. M. , Sweeney T. , Brophy P. O. , Callan J. J. , Fitzpatrick E. , McCarthy P. , O'Doherty J. V.
Published: May 2006

Twenty piglets (21 days, 7·8 kg live weight (LW)) were used in a 2×2 factorial to investigate interactions between lactose and inulin on intestinal morphology, microbiology and volatile fatty acid (VFA) production of the weanling pig. The piglets were offered the following diets for 6 days and then sacrificed: (T1) 150 g/kg lactose, (T2) 150 g/kg lactose +15 g/kg inulin, ( T3) 330 g/kg lactose, and ( T4) 330 g/kg lactose +15 g/kg inulin. Tissue samples were taken from the duodenum, jejunum and ileum for morphological measurements. Digesta samples were taken from the ileum, caecum and colon. There was an interaction ( P<0·05) between lactose and inulin in villous height in the jejunum. The inclusion of inulin at 150 g/kg lactose increased villous height compared with 150 g/kg lactose without inulin. However, inulin had no effect on villous height at 330 g/kg lactose inclusion. There was a linear relationship between food intake and villous height in the duodenum (P<0·001, R2=0·45) and the jejunum (P< 0·01, R2=0·25). The inclusion of 330 g/kg lactose increased ( P<0·05) total VFA compared with 150 g/kg lactose in the caecum and the population of lactobacilli in the caecum and colon (P<0·1). There was an interaction (P<0·05) between lactose and inulin for total VFA concentration in the colon. The pigs receiving 330 g/kg lactose had a higher total VFA concentration compared with pigs on 150 g/kg lactose. However, there was no difference between 150 g/kg and 330 g/kg lactose when the diets were supplemented with inulin. In conclusion, the inclusion of high dietary concentrations of lactose resulted in increased lactobacilli and short-chain fatty acid concentrations. The inclusion of inulin with low dietary concentrations of lactose resulted in improved intestinal health through a reduction of intestinal pH and increases in villous height.
Gammaglutamyltransferase activity in buffalo mammary tissue during lactation
Authors: Pero M. E. , Mirabella N. , Lombardi P. , Squillacioti C. , De Luca A. , Avallone L.
Published: May 2006

In the present study, the rôle of gammaglutamyltransferase (GGT) during lactation has been investigated in the water buffalo. GGT activity has been evaluated in the mammary tissue at 4 and 6 months after calving and during the non-lactating period. The highest GGT activity levels were found at day 120 (32·57±7·41 U per g) of lactation and were statistically higher than those at 180 (10·76±3·6 U per g) or during the non-lactating period (9·86±7·94 U per g). Histochemistry confirmed these findings and revealed that GGT reactivity was distributed throughout the cytoplasm of alveolar epithelial cells. Such results showed that the GGT production is high during lactation thus supporting the hypothesis that this enzyme plays a rôle in determining milk production in water buffalo by supporting milk protein synthesis.
Reproduction of wild Mongolian gerbils bred in the laboratory with respect to generation and season 2. Spermatogenic activity and testicular testosterone concentration
Authors: Blottner S. , Stuermer I.W.
Published: May 2006

Testicular activity of wild and laboratory strains of Meriones unguiculatus and its seasonal dependence was studied. Comparative intraspecific measurements were performed in adult males of the laboratory strain (LAB) and in male offspring of wild Mongolian gerbils (WF-1 to WF-3). All animals were reared under identical conditions including a constant light regime. LAB and WILD were examined in January, July and October. Testicular spermatozoa were counted, proportions of different cell types were analysed using DNA flow cytometry, and total germ cell transformation was calculated from DNA histograms. Intratesticular testosterone concentrations were measured with an enzyme immunoassay. The results showed that differences of testicular activity are dependent on the season as well as the strain and the generation. The season affected testicular parameters in LAB resulting in lowered testosterone and sperm production in July and October, respectively. In contrast, all testicular cell parameters were significantly lower for WF-1 in January compared with October. These seasonal differences were neutralized or diminished in WF-2 and WF-3. In the WILD, total testicular activity was lower and varied more in all months studied, but the differences compared with the values in LAB decreased in the successive generations. WF-3 showed the lowest discrepancy of testis weight and spermatogenic output compared with LAB. The data suggest endogenous cues for seasonal regulation of spermatogenesis, but this endogenous rhythm seems to be subsided or lost rapidly. These findings indicate rapid, adaptive changes in the early offspring generations from wild populations during breeding in the laboratory.
Genetic variability in resistance to gastro-intestinal strongyles during early lactation in Creole goats
Authors: Mandonnet N. , Menendez-Buxadera A. , Arquet R. , Mahieu M. , Bachand M. , Aumont G.
Published: May 2006

The study was undertaken in a Creole goat flock at INRA-Gardel in Guadeloupe, to evaluate the opportunity to use artificial selection as a means of controlling gastro-intestinal infection during early lactation. The flock grazed all year on Digitaria decumbens pastures. Faecal and blood samples were taken from kids at 11 months of age and from does at kidding before drenching (week 0) and at weeks 4 and 6 after kidding. Faecal egg counts (FEC) were estimated using a modified McMaster method. Blood samples were used to determine packed cell volume (PCV) and eosinophil concentrations (EOS) values. Haemonchus contortus, Trichostrongylus colubriformis and Oesophagostomum columbianum were the main strongyle species identified in faecal cultures. The data came from 1092 litters obtained from 688 does sired by 142 bucks and 413 dams. Variance and covariance components for genetic and residual effects were estimated with multivariate animal models using the restricted maximum likelihood VCE package. Repeatability and overall heritability for FEC during the post-partum period were 0·17 and 0·10±0·02. The genetic correlations between FEC and PCV were −0·56±0·11 at 4 weeks after kidding and −0·79±0·13 at 6 weeks after kidding. The genetic correlations between FEC and EOS were 0·37±0·15 at 4 weeks after kidding and 0·68±0·17 at 6 weeks after kidding. Hence, does that contributed least to pasture contamination during the postpartum period also had low EOS and high PCV breeding values. The genetic correlations between FEC measured at 11 months of age and FEC during periparturient period ranged from 0·57±0·12 to 0·76±0·16. Therefore, breeding goats for increased resistance during the post-weaning period will lead to a less marked and less persistent rise in doe FEC during early lactation. The epidemiological implications of this selection have to be quantified in terms of lower pasture contamination, lower kid parasitism, and higher milk production of does.
Lamb serum vitamin E and immunoglobulin G concentrations in response to various maternal mineral and iodine supplementation regimens
Authors: Boland T.M. , Callan J.J. , Brophy P.O. , Quinn P.J. , Crosby T.F.
Published: May 2006

The objective of the first of three studies (experiment 1) was to evaluate the effects of supplementing the pregnant ewe diet with high levels of minerals for the final 4 weeks of gestation on lamb serum vitamin E and immunoglobulin G (IgG) concentration at 24 h post partum. Sixty ewes were allocated to one of two treatments (no. =30) and offered a basal diet fortified with 52 g of supplementary minerals/vitamins containing Ca, Mg, Na, P, Co, I, Mn, Se, Zn and vitamin E (M1) for the final 4 weeks of pregnancy or no mineral/vitamin supplement was added (C1). Immediately after birth, lambs were allocated to one of four treatments in a 2×2 factorial design with the factors being ewe treatment (± minerals) and colostrum origin (± minerals). Irrespective of the colostrum origin, the progeny of the mineral supplemented ewes had lower serum vitamin E and IgG concentrations and IgG absorption efficiency at 24 h post partum (P<0·001). In a second study (experiment 2), 44 ewes were allocated to one of four treatments (no. =11) in week 13 of pregnancy and offered a basal diet in addition to one of the following mineral/vitamin fortifications: 0 g (C2), 52 g of a mineral supplement as in experiment 1 (M2), a supplement as in M1 but with iodine excluded (-I), iodine only offered at a rate (40 mg per ewe per day) equivalent to 52 g of minerals (IO). When iodine was offered either M2 (P<0·01) or (IO) (P<0·001) it resulted in the progeny having a reduced serum vitamin E concentration at 24 h post partum. The -I progeny had higher serum vitamin E concentrations at 24 h post partum than the progeny of treatments C2, M2 (P<0·01) and IO (P<0·001). In a third study (experiment 3) the effect of incremental levels of iodine supplementation on lamb serum vitamin E concentration was studied. Forty-eight ewes were allocated to one of four treatments (no. =12) and offered the following levels of supplementary dietary iodine: 0 mg (C3), 8·9 mg (LI), 17·7 mg (MI) or 26·6 mg (HI) for the final 6 weeks of pregnancy. There was a linear (P<0·001) reduction in lamb serum vitamin E concentration as maternal iodine supplementation increased. We conclude that when ewes are offered high levels of iodine during the final 6 weeks of gestation their progeny are pre-programmed in utero to have a reduced ability to absorb colostral vitamin E. These findings support our earlier studies and provide further evidence of the need to reduce the current toxicity values for iodine. for the ewe in late pregnancy.
The effect of slaughter weight and sexual status on performance characteristics of male Holstein-Friesian cattle offered a cereal-based diet
Authors: Kirkland R. M. , Keady T. W. J. , Patterson D. C. , Kilpatrick D. J. , Steen R. W. J.
Published: May 2006

A total of 180 Holstein-Friesian male calves, mean age and live weight (LW) at start of the study 112 (s.d. 26·0) days and 134 (s.d. 37·6) kg, respectively, were used to evaluate the effect of slaughter weight on food efficiency and animal performance. Animals were offered concentrates ad libitum and a restricted quantity of straw and slaughtered at one of six LWs as bulls: 300, 350, 400, 450, 500 or 550 kg. A further group of cattle were slaughtered as steers at 450 kg LW. Mean age at slaughter was 247 and 434 days for bulls slaughtered at 300 and 550 kg LW respectively. Neither rate of LW or carcass gain was influenced by weight at slaughter ( P>0·05), with mean values of 1·31 and 0·70 kg/day, respectively. Food conversion ratio, killing-out proportion, carcass conformation, fat classification and weight of internal fat depots increased ( P<0·001) as slaughter weight of the bulls increased. In the comparison of steers and bulls slaughtered at 450 kg, steers had lower ( P<0·001) rates of LW and carcass gains and had a higher ( P<0·001) food conversion ratio than comparable bulls. Steers had lower ( P<0·001) estimated carcass lean, and higher ( P<0·01) estimated carcass fat concentrations than bulls slaughtered at the same LW.
Carcass and muscle characteristics of beef cull cows between 4 and 9 years of age
Authors: Jurie C. , Martin J-F. , Listrat A. , Jailler R. , Culioli J. , Picard B.
Published: May 2006

The effects of age and breed on carcass and muscle characteristics of cull cows slaughtered at the same fattening state between 4 and 9 years of age were analysed in four French breeds: Aubrac (AU), Charolais (CH), Limousin (LI), and Salers (SA). Muscle characteristics were determined in three muscles: longissimus thoracis (LT), semitendinosus (ST) and triceps brachii (TB). They included: (1) the % frequency, cross-sectional area and % area of the different fibre types classified according to their contraction rate and metabolic properties (slow twitch oxidative (SO), fast twitch oxidative glycolytic (FOG) and fast twitch glycolytic (FG)), (2) the isocitrate dehydrogenase (ICDH) and lactate dehydrogenase (LDH) activities, representative of oxidative and glycolytic metabolism respectively, and (3) the total and insoluble collagen contents. Whatever the age of the animals at slaughter, the same carcass composition, fibre characteristics (% frequency, area, % area) and metabolic enzyme activities were obtained whatever the muscles considered. In contrast, important differences between breeds were observed in carcass composition (muscle, fat, bone) and enzyme activities. CH cows presented the highest final live weight and LI carcasses were characterized by higher muscle weight, lower fat and bone weights and more glycolytic muscles. Among the muscle characteristics, collagen was the most influenced by age and breed in a breed and muscle dependent manner respectively. AU and LI cows exhibited lower total and insoluble collagen contents than CH and SA cows, particularly at 6 to 7 years of age and for the LT and ST muscles. Thus collagen could explain an important part of the variability in meat quality from cull cows. In conclusion, results of this study provide consistent data on muscle characteristics of cull cows, few studies were available until then.
Effects of dietary protein content and feeding level on carcass characteristics and organ weights of Iberian pigs growing between 50 and 100 kg live weight
Authors: Barea R. , Nieto R. , Lara L. , García M.A. , Vílchez M.A. , Aguilera J.F.
Published: May 2006

The effects of dietary protein content and level of feeding on carcass characteristics and organ weights were studied in castrated male Iberian pigs growing from 50 to 100 kg live weight (LW). Animals were offered four diets providing 145, 120, 95 and 70 g ideal crude protein (CP) per kg dry matter (DM) and 13·94, 14·29, 14·56 and 14·83 MJ metabolizable energy (ME) per kg DM, respectively. Three levels of feeding were assayed: 0·60, 0·80 and 0·95 of ad libitum intake. The pigs were slaughtered at 100 kg LW. Daily gain in carcass (carcass gain, g/day) and protein deposition (PD, g/day) in this component attained 76·2% and 78·8% of whole-body average daily gain and PD, respectively. Carcass gain improved with each decrease in dietary CP from 145 up to 120 g/kg DM and then levelled off. A small but significant effect of dietary CP on carcass composition was observed, due to an enhanced fat deposition in pigs fed the lowest protein content diet. Mean values of protein, fat, ash and water contents in the carcass were 101·8, 522·7, 27·6 and 353·7 g/kg respectively. PD in the eviscerated carcass was not affected significantly by dietary protein level but tended to reach a maximum value with the diet that provided 95 g CP per kg DM: 55·7 g/day at the highest feeding level assayed. Carcass energy retention (MJ/day) increased significantly (P<0·001) with decreasing dietary protein supply and on increasing level of feeding. Raising feed intake resulted in a significant decrease for carcass and a concomitant increase for viscera, as proportions of empty body weight (P<0·05 andP<0·001, respectively). Proportional weights of shoulder and ham were not affected either by dietary CP content or feeding level. Proportionate weights of dissectable fat in the shoulder and intermuscular and subcutaneous fat in the ham were not affected by CP content of the diet. In contrast, intermuscular fat content of ham was increased by feeding level (P<0·05), likely with implications for the quality of the cured meat product.
Predicting carcass composition of terminal sire sheep using X-ray computed tomography
Authors: Macfarlane J. M. , Lewis R. M. , Emmans G. C. , Young M. J. , Simm G.
Published: May 2006

The best means to utilize X-ray computed tomography (CT) and ultrasound to predict carcass lean, fat and bone weights in vivo in terminal sire sheep were tested. Data on 160 lambs from three breeds were considered: 50 Suffolk males, 50 Suffolk females, 40 Texel males and 20 Charollais males. One-fifth of the lambs within each breed and sex group were slaughtered at each of 14, 18 and 22 weeks of age and the remaining two-fifths at 26 weeks. Carcasses were dissected into lean, fat and bone weights. Prior to slaughter all lambs were CT scanned, with cross-sectional scans taken at seven sites along the body (ischium, hip, mid shaft of femur, 2nd and 5th lumbar vertebrae and 6th and 8th thoracic vertebrae), and ultrasound scanned at the 3rd lumbar vertebra and 13th rib.A set of three CT scans that reliably predicted carcass lean, fat and bone weights was identified which included a scan in each of the three main carcass regions: ischium in the hind leg, 5th lumbar vertebra in the loin and 8th thoracic vertebra in the shoulder. Breed and sex affected the intercepts of the prediction equations but not their slopes. Therefore, a minimal set of equations is likely to be sufficient to predict tissue weights, at least within terminal sire sheep breeds. Equations derived showed high degrees of fit to the data with R2values of 0·924, 0·978 and 0·830 for lean, fat and bone weights, respectively, when predicted using CT alone, and 0·589 and 0·857 for lean and fat weights, respectively, when predicted using ultrasound alone. Using live weight in addition to CT information only improved prediction accuracy slightly for lean (0·966) and fat (0·986) although more substantially for bone (0·925). Where live and tissue weights are considered contemporaneously in genetic evaluations, excluding live weight from prediction may therefore be preferable to avoid colinearity among weight measures.
Influence of chicory roots (Cichorium intybusL)on boar taint in entire male and female pigs
Authors: Hansen L. L. , Mejer H. , Thamsborg S. M. , Byrne D. V. , Roepstorff A. , Karlsson A. H. , Hansen-Møller J. , Jensen M. T. , Tuomola M.
Published: May 2006

Boar taint is an off-flavour of pork caused primarily by a microbial breakdown product, skatole and a testicular steroid, androstenone. As skatole is produced in the large intestine from tryptophan, it is possible that some ‘bioactive’ ingredients could modify protein fermentation and, in the process, diminish boar taint. The aim of this study was to examine the effect of inulin-rich chicory roots (Cichorium intybusL.) on boar taint. In the first of three trials individually penned, entire males and females were given an organic concentrate in which 0·25 of the daily energy intake was replaced with crude chicory roots for 9 or 4 weeks prior to slaughter. In the second trial, entire male pigs were given diets that included, either crude chicory roots, dried chicory roots, or inulin (extracted from chicory roots) for 6 weeks pre-slaughter. In the third trial, intact male pigs were given the dried chicory diet for either 2 or 1 week before slaughter. In all trials the chicory diets were offered on a scale at 0·95 of the Danish recommendation for energy intake, and pig performance was compared with a control group given the organic concentrate at 0·95 of recommended energy intake plus silage ad libitum. In trial 1 an additional control group was offered the organic concentrate at a daily energy intake level of 1·0 of Danish recommendations. The pigs in trials 1, 2, and 3 were slaughtered at an average live weight of 118, 124, and 110 kg, respectively, in order to ensure that they had achieved sexual maturity. Overall, skatole concentrations in blood plasma and backfat at slaughter were reduced to almost zero levels by including crude or dried chicory or inulin in the diet. This occurred irrespective of sex and length of feeding period (1 to 9 weeks). In trial 3 a significant effect on blood plasma concentration was observed after 3 days of feeding a diet containing dried chicory. The only significant reduction in plasma androstenone levels was detected in pigs given the crude chicory for a 9 week duration in trial 1. The production and proportion of lean was generally not affected by the addition of either form of chicory to the diets in trials 1 and 2. Therefore, dried chicory may be the most suitable form for commercial use because it: had no initial adverse effects on food intake, consistently reduced skatole without reducing performance, was easy to handle throughout the entire year and is relatively inexpensive.
Feeding with chicory roots reduces the amount of odorous compounds in colon and rectal contents of pigs
Authors: Jensen M. T. , Hansen L. L.
Published: May 2006

Sixteen pigs (eight entire males and eight females) were given individually two diets, control and control added 25% chopped chicory roots for 2 months before slaughter. Samples were taken from the contents in colon and rectum and subjected to GC-MS analysis for amount of odour impact compounds. The compounds 2-pentanone, ethylbutyrate, propylpropionate, butyric acid, ethyl-2-methylbutyrate, p-cresol, indole and skatole showed a significant difference between the two treatments. The esters, which have relatively pleasant, often fruity odours, increased in the chicory treatment, whereas the malodorous compounds, p-cresol, indole and skatole decreased in the chicory treatment. The measured amounts of compounds were corrected for their odour thresholds as different compounds can have widely different odour thresholds. Principal components analysis was then used to analyse the raw and corrected data results. p-Cresol was the most malodorous compound and together with skatole and indole count as the most malodorous compounds in the colon and rectum cotents. However, butyric acid also had some minor influence. Feeding chicory roots decreased significantly the concentrations of these malodorous compounds, especially if the lowest odour threshold values are used as correction factors.
The effect of cyadox supplementation on metabolic hormones and epidermal growth factor in pigs
Authors: Zhu H. L. , Yuan Z. H. , Wang Y. L. , Qiu Y. S. , Fan S. X.
Published: May 2006

This study was conducted to evaluate the effect of cyadox on endocrine hormones and growth factor in pigs. Forty-eight crossbred pigs (35±7 days) were randomly allotted to one of four treatments, with six replicate pens per treatment and two pigs per pen. Pigs were offered one of four diets including a control diet or the control diet supplemented with cyadox at either 25, 50 or 100 mg/kg for 8 weeks. Growth performance data and serum were collected every 2 weeks. Serum epidermal growth factor (EGF), insulin, thyroid hormones (tri-iodothyronine (T3) and thyroxine (T4)), and cortisol concentrations were determined. Results indicated that average daily gain (ADG) and gain/food ratio increased linearly and quadratically with increasing cyadox levels. The treatment containing cyadox at 50 mg/kg improved ADG by proportionately 0·241 and food efficiency by 0·25 (P<0·05) during the entire experiment. In our study, EGF (during weeks 4 to 8), insulin (during weeks 4 to 6), thyroid hormones (in week 4) concentrations increased quadratrically (P<0·05) and the cortisol concentrations (in week 4) decreased linearly (P<0·01) with increasing supplementation of cyadox. Pigs given 50 mg/kg cyadox diet had greater (P<0·05) EGF concentrations than pigs on other diets throughout the experiment. An increase (proportionately 0·22) in serum insulin concentrations in cyadox group was also observed (P<0·05) in week 4. From week 2 to week 4, the T4concentrations of cyadox group increased by 50% (P<0·05). Moreover, feeding cyadox to pigs elevated their serum T3concentrations (P<0·05) in the 4th week and 8th week. The cortisol concentrations of cyadox group were decreased (P<0·05) in week 4. These results suggest that cyadox improve pig performance by altering concentrations of peripheral metabolic hormones and growth factor.
Contribution of natural food sources to reproductive behaviour, fecundity and longevity ofCeratitis cosyra,C. fasciventrisandC. capitata(Diptera: Tephritidae)
Authors: Manrakhan A. , Lux S.A.
Published: May 2006

The influence of food sources comprising the natural diet on the reproductive behaviour, fecundity and longevity of three African fruit fliesCeratitis cosyra(Walker),C. fasciventris(Bezzi) andC. capitata(Wiedemann) was investigated. Three natural food sources, varying in protein and sugar content, were evaluated. These included bird droppings (farm chicken), aphid honeydew and guava (Psidium guajavaL.) juice. ForC. fasciventrisandC. capitata, flies fed on a protein-rich diet displayed higher frequency of calling, mating and oviposition than flies fed on a protein-poor diet, whilst forC. cosyra, quality of diet significantly influenced the mating behaviour of the flies, but not the calling and oviposition behaviour. Net fecundity rates were lowest forC. fasciventrisandC. capitatawhen fed only on guava juice (0.1, 2.6 eggs per female, respectively), and higher for those on a diet of honeydew only (9.5, 33.8 eggs per female, respectively) and a combined diet of guava, honeydew and chicken faeces (11.8, 25.8 eggs per female, respectively). ForC. cosyra, due to low numbers of eggs collected, no significant differences in fecundity between diets could be detected. All species fed only on a diet of chicken faeces since emergence died within the first three days of adult life without laying eggs, but when carbohydrates were provided by addition of guava juice and honeydew, the longevity of the flies was sustained for more than four weeks after adult emergence. The practical implications of these findings for control purposes are discussed.
Reproductive traits of Monochamus galloprovincialis (Coleoptera: Cerambycidae) under laboratory conditions
Authors: Naves P. , de Sousa E. , Quartau J.A.
Published: May 2006

The pine sawyer Monochamus galloprovincialis (Olivier) is the vector of the introduced pine wood nematode Bursaphelenchus xylophilus (Steiner & Bührer) Nickle in Portugal, and until recently was considered a secondary forest insect. Under laboratory conditions, a study of biological and reproductive traits of 37 insect pairs was conducted. The longevity of both sexes was similar, being 61.2±6.5 days for males and 64.0±6.3 days for females (mean±SE). Sixteen small-sized insects (22% of the population) died within 20 days and before starting to reproduce. The sexual maturation period (without egg laying) was 20.4±0.7 days (mean±SE), while the oviposition period lasted 54.0±4.2 days (mean±SE). The oviposition rate increased very quickly during the first weeks of life, peaking to almost two eggs per day during days 30–44, and gradually dropping in the following weeks. The females laid an average of 67.0±5.96 (mean±SE) eggs through their lives. The hatch rate was 92.6±1.0%; (mean±SE). There were large individual variations in longevity and fecundity parameters, and principal component analysis based on 16 morphological and biological parameters separated the breeding insects into four distinct groups. Almost half of the reproducing beetles were large-sized insects, with high longevity and fecundity traits. Overall, the reproductive potential of the Portuguese population of M. galloprovincialis seems to be smaller than that described for other Monochamus vectors of the pine wood nematode both in North America and Japan.
Supercooling points and diapause termination in overwintering adults of orchard bees Osmia cornuta and O. rufa (Hymenoptera: Megachilidae)
Authors: Krunić M.D. , Stanisavljević L.Ž.
Published: May 2006

The orchard bee species Osmia cornuta (Latreille) and O. rufa (Linnaeus) are both European in distribution. Osmia cornuta is distributed in the central and southern half of the continent, while O. rufa is distributed additionally in more northern parts of Europe, including Great Britain. These bees over-winter in cocoons as diapausing adults. The freezing temperatures of overwintering adults of O. cornuta and O. rufa during diapause are similar: −30°C to −24°C and −31°C to −26°C, respectively. However, there are differences in the termination of their diapause. Under natural conditions in the wider area of Belgrade, O. rufa appears in spring about two weeks later than O. cornuta.
The mode of action of insecticidal controlled atmospheres
Authors: Mitcham E. , Martin T. , Zhou S.
Published: May 2006

Arthropods cope with reduced oxygen and elevated carbon dioxide atmospheres with a reduction in metabolic rate, also called metabolic arrest. The reduction in metabolism lessens the pressure on the organism to initiate anaerobic metabolism, but also leads to a reduction in ATP production. The natural permeability of cellular membranes appears to be important for the survival of the arthropod under low oxygen or high carbon dioxide atmospheres. Despite the similarities in response, arthropod mortality is generally greater in response to high carbon dioxide as apposed to low oxygen atmospheres. There appears to be a greater decrease in ATP and energy charge in arthropods exposed to high carbon dioxide as compared with low oxygen atmospheres, and this may be due to greater membrane permeability under carbon dioxide leading to an inefficient production of ATP. Reduced oxygen and elevated carbon dioxide atmospheres can have an additive effect in some cases, depending on the concentrations used. The effect of these atmospheres on arthropods depends also on temperature, species and life stage. Additional work is needed to fully understand the mode of action of controlled atmospheres on arthropod pests.
New contributions towards the understanding of the phylogenetic relationships among economically important fruit flies (Diptera: Tephritidae)
Authors: Segura M.D. , Callejas C. , Fernández M.P. , Ochando M.D.
Published: May 2006

Fruit flies (Diptera: Tephritidae) are a species-rich and economically important group. The phylogenetic relationships among the many taxa are still to be fully resolved and the monophyly of several groups is still to be confirmed. This paper reports a study of the phylogenetic relationships among 23 economically important tephritid species (representing several major lineages of the family) which examines the sequence of a region of mitochondrial DNA encompassing the cytb, tRNASer and ND1 genes. Substitutions characteristic of particular taxa were found that could help classify members of the family at any developmental stage. The trees obtained by the maximum parsimony, neighbour joining and maximum likelihood methods were generally compatible with present morphological classification patterns. However, the data reveal some characteristics of the phylogenetic relationships of this family that do not agree with present classifications. The results support the probable non-monophyletic nature of the subfamily Trypetinae and suggest that Bactrocera cucurbitae (Coquillet) is more closely related to the genus Dacus than to other species of Bactrocera.