Less absorbed solar energy and more internal heat for Jupiter.

The radiant energy budget and internal heat are fundamental properties of giant planets, but precise determination of these properties remains a challenge. Here, we report measurements of Jupiter's radiant energy budget and internal heat based on Cassini multi-instrument observations. Our findings reveal that Jupiter's Bond albedo and internal heat, 0.503 ± 0.012 and 7.485 ± 0.160 W m-2 respectively, are significantly larger than 0.343 ± 0.032 and 5.444 ± 0.425 Wm-2, the previous best estimates. The new results help constrain and improve the current evolutionary theories and models for Jupiter. Furthermore, the significant wavelength dependency of Jupiter's albedo implies that the radiant energy budgets and internal heat of the other giant planets in our solar system should be re-examined. Finally, the data sets of Jupiter's characteristics of reflective solar spectral irradiance provide an observational basis for the models of giant exoplanets.

Assembly of a π-π stack of ligands in the binding site of an acetylcholine-binding protein.

Acetylcholine-binding protein is a water-soluble homologue of the extracellular ligand-binding domain of cys-loop receptors. It is used as a structurally accessible prototype for studying ligand binding to these pharmaceutically important pentameric ion channels, in particular to nicotinic acetylcholine receptors, due to conserved binding site residues present at the interface between two subunits. Here we report that an aromatic conjugated small molecule binds acetylcholine-binding protein in an ordered π-π stack of three identical molecules per binding site, two parallel and one antiparallel. Acetylcholine-binding protein stabilizes the assembly of the stack by aromatic contacts. Thanks to the plasticity of its ligand-binding site, acetylcholine-binding protein can accommodate the formation of aromatic stacks of different size by simple loop repositioning and minimal adjustment of the interactions. This type of supramolecular binding provides a novel paradigm in drug design.

A giant thunderstorm on Saturn.

Lightning discharges in Saturn's atmosphere emit radio waves with intensities about 10,000 times stronger than those of their terrestrial counterparts. These radio waves are the characteristic features of lightning from thunderstorms on Saturn, which last for days to months. Convective storms about 2,000 kilometres in size have been observed in recent years at planetocentric latitude 35° south (corresponding to a planetographic latitude of 41° south). Here we report observations of a giant thunderstorm at planetocentric latitude 35° north that reached a latitudinal extension of 10,000 kilometres-comparable in size to a 'Great White Spot'-about three weeks after it started in early December 2010. The visible plume consists of high-altitude clouds that overshoot the outermost ammonia cloud layer owing to strong vertical convection, as is typical for thunderstorms. The flash rates of this storm are about an order of magnitude higher than previous ones, and peak rates larger than ten per second were recorded. This main storm developed an elongated eastward tail with additional but weaker storm cells that wrapped around the whole planet by February 2011. Unlike storms on Earth, the total power of this storm is comparable to Saturn's total emitted power. The appearance of such storms in the northern hemisphere could be related to the change of seasons, given that Saturn experienced vernal equinox in August 2009.

The POTENT II randomised trial: efficacy and safety of an orodispersible vardenafil formulation for the treatment of erectile dysfunction.

AIMS: The aim of this study was to investigate the efficacy and safety of 10 mg vardenafil orodispersible tablet (ODT) vs. placebo in a general population of men with erectile dysfunction (ED). METHODS: This was a double-blind, multicentre, randomised, parallel-group, placebo-controlled study conducted at 35 centres in Australia, Canada, Mexico and the United States. Subjects aged > or =18 years, with ED for at least 6 months, were randomised to receive 12 weeks of on-demand treatment with either 10 mg vardenafil ODT or placebo. Each treatment group was stratified such that approximately half of the subjects were aged > or = 65 years. Primary efficacy variables were the erectile function domain of the International Index of Erectile Function (IIEF-EF) and Sexual Encounter Profile questions 2 (SEP2) and 3 (SEP3). Secondary variables included SEP diary questions 1, 4, 5 and 6, the patient version of the Treatment Satisfaction Scale (TSS) and the Global Assessment Question (GAQ). RESULTS: Of the 473 men enrolled in the study (51.4% aged > or =65 years), 331 were included in the intent-to-treat population (vardenafil ODT, n = 169; placebo, n = 162). Vardenafil ODT therapy was statistically significantly superior to placebo for all primary (i.e. IIEF-EF, SEP2, SEP3) and secondary efficacy variables (p < 0.0001). Treatment-emergent adverse events were mostly mild to moderate in severity, and comparable in both incidence and type with those of the film-coated tablet formulation. CONCLUSIONS: Treatment with 10 mg vardenafil ODT, taken on demand, significantly improved erectile function and was effective and well tolerated in a broad population of men with ED.

Effect of the major histocompatibility complex on the inhibition of induced cellulitis development in a broiler chicken model.

The chicken major histocompatibility complex (MHC) has been implicated in conferring resistance or susceptibility to several bacterial, parasitic, and viral diseases, the most notable of which is Marek's disease. In Marek's disease certain MHC haplotypes have been shown to confer relative resistance (B21), whereas other haplotypes are susceptible (B13). Relatively little work has been performed looking at the association of the MHC with bacterial diseases. One such disease is cellulitis, which is caused by several different bacteria but most notably by Escherichia coli. In this report, a commercial broiler chicken line known to contain standard B13 and B21, as well as the unique MHC types BA9 and BA12, was examined in a challenge model for cellulitis. The MHC-defined birds were challenged with a cellulitis-causing E. coli isolate and the frequency of lesion development and severity was quantified. In conclusion, B21 had the highest incidence of cellulitis development, B13 had the lowest incidence, and BA9 and BA12 had intermediate results. Results concerning the lesion severity showed that it was independent of the birds' MHC type.

Pathogenesis of infectious bronchitis virus in vaccinated chickens of two different major histocompatibility B complex genotypes.

Infectious bronchitis (IB) disease progression in vaccinated chickens after challenge was evaluated in a single commercial line of layer chickens presenting two different major histocompatibility complex (MHC) B complex genotypes. MHC B genotypes were determined by DNA sequence-based typing of BF2 alleles. In total, 33 B2/B15 and 47 B2/B21 chickens were vaccinated with an Ark-type IB virus (IBV) attenuated vaccine and challenged with Ark-type IBV field isolate AL/4614/98 14 days later. Additional chickens of both genotypes served as unvaccinated/challenged and unvaccinated/nonchallenged controls. Clinical signs, histopathologic analysis, detection of IBV genomes in tears, and IBV-specific immunoglobulin A (IgA) in tears were used to evaluate disease progression and immune response. The incidence of IBV respiratory signs was significantly higher in B2/21 than in B2/B15 MHC genotype birds. However, neither the severity and duration of respiratory signs nor the severity and incidence of histologic lesions differed significantly with MHC genotype. The levels of IBV-specific IgA in tears of vaccinated and challenged chickens did not differ significantly between MHC genotypes. IBV genomes were present in the tears of vaccinated and challenged birds, and the incidence of detectable IBV genomes did not vary significantly with MHC B genotype. From an applied perspective, these results indicate that vaccinated commercial outbred chickens with these MHC genotypes are equally resistant to IBV.

MX1 exon 13 polymorphisms in broiler breeder chickens and associations with commercial traits.

The Mx1 gene in mice is induced by type I interferons and is the major determinant of resistance to influenza virus and related orthomyxoviruses. It has been previously shown that a SNP in exon 13 of the chicken MX1 gene determines differential antiviral activity of the protein. We evaluated this SNP and two additional SNPs in elite broiler lines by PCR amplification and sequence analysis. Associations between MX1 exon 13 SNPs and several traits of economic interest were evaluated. Significant associations were found between the SNP determining antiviral activity and mortality in one line and leg defects in another line.

Associations of BF2 alleles with antibody titres and production traits in commercial pure line broiler chickens.

Three commercial broiler pure lines were evaluated for associations of sire BF2 (major histocompatibility complex class I) alleles with progeny phenotypic traits. Significant BF2 associations with a subset of traits were observed in two lines. The BF2*21 allele was positively associated with antibody titre to infectious bursal disease virus in both lines. Other associations were line-specific.

Serological evidence of chicken infectious anemia virus in the United States at least since 1959.

A retrospective, serological survey was performed to determine an approximate time frame for when chickens were first exposed to chicken anemia virus (CAV) in the southeastern United States. A serum collection covering most of the period between 1959 and 2005 was available for the present study. These sera were obtained from adult chicken flocks that were maintained in experimental chicken farms at Auburn University's Department of Poultry Science. Sera were tested for the presence of CAV-specific antibodies using a commercially available competitive enzyme-linked immunosorbent assay (ELISA) kit. Values <0.6 were considered positive. Fresh sera obtained from hens in 2005 showed 45.5% negative and 54.5% positive for CAV antibodies. The assessment of serum samples covering the time period of 1959 through 1979 resulted in most sera being positive for CAV antibodies. The percentage of positive samples between years varied from 43% to 100%. These serological results support assumptions based on circumstantial evidence that CAV must have been present in the United States long before its first isolation in 1989.

High-resolution typing for chicken BF2 (MHC class I) alleles by automated sequencing.

Sequence-based typing (SBT) was developed for major histocompatibility complex (MHC) class I and class II alleles in humans. We report here the development and application of a SBT method for alleles of the chicken BF2 locus (the more polymorphic of the two MHC class I loci in chickens). Exon 2 of the BF2 gene was selectively amplified from genomic DNA using a BF2 locus-specific PCR primer. Exon 2 sequences were sufficient to identify the 21 distinct BF2 alleles described in standard B haplotypes of Leghorns and in commercial broiler-breeder lines. Sixty-six samples from MHC typed, pedigreed chickens were tested, including 50 different heterozygous combinations. BF2 sequences from all B homozygotes were successfully amplified, and all combinations of BF2 alleles in heterozygotes were co-amplified equally. The two different BF2 alleles in heterozygotes could be identified unambiguously by distinct sequence motif patterns. In tests of samples of unknown B genotype in commercial broiler-breeder flocks, we identified expected BF2 alleles as well as an allele not previously encountered in one of the lines.

The avian major histocompatibility complex influences bacterial skeletal disease in broiler breeder chickens.

This study evaluated bacterial skeletal disease in conjunction with the major histocompatibility complex (MHC) in a genetically pure line of broiler breeder chickens. Chickens from six broiler breeder flocks were examined for skeletal lesions, bacterial pathogens, and MHC genotype. During a 10-week period, eighty-eight, 9- to 21-week-old lame chickens and 34 normal, age-matched controls were selected. Tenosynovitis, arthritis, and femoral or tibiotarsal (or both) osteomyelitis occurred in 86 of 88 (97.7%) lame chickens. Ninety-five bacterial isolates were obtained from 83 of 88 (94.3%) lame birds and 4 of 34 (11.8%) controls. Staphylococcus spp. was isolated from 72.6% of the skeletal lesions, predominantly Staphylococcus aureus (38.9%). MHC B complex genotypes were determined by hemagglutination for 88 lame birds, 34 controls, and 200 randomly selected birds from each of the six flocks (1,200 total). Combined chi-square analysis revealed that the homozygous MHC genotypes B(A4/A4) (chi(2) = 14.54, P = 0.0063) and B(A12/A12) (chi(2) = 42.77, P = 0.0001) were overrepresented in the sample of symptomatic birds compared with random samples from the same flocks. The homozygous A4 and A12 MHC genotypes influenced flock chi-square values more than the corresponding heterozygotes. An MHC B complex influence on bacterial skeletal disease was apparent in this line of broiler breeders.

Oral infection with chicken anemia virus in 4-wk broiler breeders: lack of effect of major histocompatibility B complex genotype.

The pathologic consequences of chicken anemia virus (CAV) oral inoculation in 4-wk-old broiler breeders of different major histocompatibility B complex (MHC) genotypes were evaluated. MHC B complex was determined by hemagglutination and sequence-based typing. Clinical signs, serology, gross lesions, histopathologic analysis, and CAV genome quantification were used to evaluate disease progression. Clinical disease was not apparent in the inoculated broilers throughout the experimental period. At 14 days postinoculation, antibodies against CAV were detected in 26.4% (29/110) of the inoculated birds. The distribution of percent positive was 34.6% (9/26) and 32.3% (10/31) of the chickens with B A9/A9 and B A9/A4 MHC genotypes, respectively, and seroconversion in six other genotypes was 19% (10/53). These differences among MHC genotypes for specific seroconversion rate were not statistically significant. CAV genomes were detected in the thymus of 87.7% (93/110) of the inoculated birds with no statistically significant differences between MHC genotypes. Mild thymic lymphocytolysis, lymphedema, and medullary hemorrhage were observed in the inoculated chickens. Histomorphometric analysis showed that cortical lymphocyte-to-parenchyma ratios did not differ between inoculated and uninoculated groups or among MHC genotypes. Similar findings have been reported previously in white-leghorn chickens of similar age, suggesting that broilers show a similar resistance to the effects of CAV infection at this age. The absence of significant clinical and pathological changes in the orally inoculated broilers at this age contrasts with CAV-associated thymus damage seen frequently in condemned commercial broilers at harvest.

Distinctive polymorphism of chicken B-FI (major histocompatibility complex class I) molecules.

The major histocompatibility complex (MHC) in chickens influences disease resistance, but the mechanism is not understood. In Leghorn lines, the MHC contains 2 closely-linked class I loci, B-FI and B-FIV. Previously, we determined nucleotide sequences of well-expressed class I (B-F) genes from unique MHC haplotypes of broiler chicken lines. More recently, we identified 7 new B-F alpha1alpha2-coding sequences from less well-expressed loci by amplification of genomic DNA from unique broiler haplotypes. Phylogenetic analysis of chicken MHC class I alpha1alpha2-coding sequences resolved 2 clusters (Groups A and B), which appear to correspond to B-FIV and B-FI loci, respectively. Compared with B-FIV locus, B-FI alleles were less polymorphic overall, but nevertheless demonstrated evidence of diversifying selection. The most striking feature of B-FI alleles is a conserved, locus-specific motif in the alpha helix of the alpha1 domain, a region that is highly variable in B-FIV alleles. This distinctive pattern of allelic polymorphism resembles that of the HLA-C class I locus in the human MHC (HLA). The conservation of the alpha helix of the alpha1 domain relates to HLA-C interaction with members of the killer immunoglobulin-like receptors on natural killer (NK) cells that are specific for recognition of HLA-C molecules and function to regulate activation of NK cells. Whereas HLA-C molecules may be dominant ligands for NK cell regulation, HLA-A and -B molecules are more important in presenting antigen to cytotoxic T lymphocytes. We hypothesize that chicken B-FI molecules may be specialized to serve similar functions as HLA-C molecules.

Diversity and locus specificity of chicken MHC B class I sequences.

The major histocompatibility complex B (MHC B) region in a standard haplotype of Leghorn chickens contains two closely linked class I loci, B-FI and B-FIV. Few sequences of B-FI alleles are available, and therefore alleles of the two loci have not been compared with regard to sequence diversity or locus specificity. Here, we report eight new B-F alpha 1/alpha 2-coding sequences from broiler chicken MHC B haplotypes, and a unique recombinant between the two B-F loci. The new sequences were combined with existing B-F sequences from Leghorn and broiler haplotypes for analysis. On the basis of phylogenetic analysis and conserved sequence motifs, B-F sequences separated into two groups (Groups A and B), corresponding to B-FIV and B-FI locus, respectively. Every broiler haplotype had one B-F sequence in Group A and the second B-F sequence, if it existed, clustered in Group B. Group B (presumptive B-FI locus) sequences identified in broiler haplotypes resembled the human MHC class I HLA-C locus in their distinctive pattern of allelic polymorphism. Compared with B-FIV, B-FI alleles were less polymorphic and possessed a conserved locus-specific motif in the alpha1 helix, but nevertheless demonstrated evidence of diversifying selection. One B-FI alpha 1/alpha 2-coding nucleotide sequence was completely conserved in four different broiler haplotypes, but each allele differed in the exon encoding the alpha 3 domain.

Major histocompatibility complex effect on cellulitis among different chicken lines.

The chicken major histocompatibility complex (MHC) has been implicated in conferring resistance/susceptibility to several bacterial, parasitic, and viral diseases. Investigators have shown that the chicken MHC plays a major role in determining the outcome of a Marek's disease infection, in that standard B(13) is susceptible to the virus while B(21) confers resistance to the virus. Previous work with a broiler line has shown that B(21) is susceptible to an Escherichia coli-induced cellulitis infection and that B(13) conferred resistance to the infection. For this experiment, a broiler and a Leghorn chicken line shown to contain standard B(13) and B(21) were examined in a challenge model for cellulitis. The birds were challenged with a cellulitis-causing E. coli isolate. Homozygous B(21) had the highest incidence of cellulitis development compared with either homozygous B(13) or the heterozygous B(13)/B(21) for both the broiler and Leghorn lines. Additionally, cellulitis lesion severity was measured in both lines and shown to be independent of MHC type.

Quantitative measures of disease in broiler breeder chicks of different major histocompatibility complex genotypes after challenge with infectious bursal disease virus.

Criteria for evaluating genetic differences in resistance and susceptibility to infectious bursal disease (IBD) within a commercial broiler breeder line of chickens were compared. Line A broiler breeder chickens were challenged with graded doses of Animal and Plant Health Inspection Service (APHIS) strain IBD virus (IBDV) and evaluated at 2 time points, 3 days postinoculation (PI) and 10 days PI. Measures obtained at both time points included bursa to body weight, bursa histology, bursa lymphocyte count, and percentage of T cells in the bursa. Furthermore, viral load in the bursa was determined 3 days PI and anti-IBDV antibody titers, 10 days PI. A dose of 50 50% embryo infective dose caused IBD in about half the line A birds at the 10-day time point, and this dose was chosen for further studies. The data were analyzed for correlation among the various measures. Comparison of the 3-day- and 10-day-PI bursa lymphocyte counts indicated that birds challenged with low doses of virus suffered lymphocyte depletion at the 3-day time point, but many or all (depending on the dose) recovered by the 10-day time point. With a viral dose that caused bursal atrophy in about half the birds by 10 days PI, families segregating for 2 major histocompatibility complex (MHC) haplotypes were compared in terms of resistance to IBD. Results indicated that there was no difference among the 3 MHC genotypes in incidence of IBD by any of the disease measures.

Single-strand conformation polymorphism (SSCP) assays for major histocompatibility complex B genotyping in chickens.

We have developed a DNA-based method for defining MHC B system genotypes in chickens. Genotyping by this method requires neither prior determination of allele-specific differences in nucleotide sequence nor the preparation of haplotype-specific alloantisera. Allelic differences at chicken B-F (class I) and B-L (class II) loci are detected in PCR single-strand conformation polymorphism (SSCP) assays. PCR primer pairs were designed to hybridize specifically with conserved sequences surrounding hypervariable regions within the two class I and two class I loci of the B-complex and used to generate DNA fragments that are heat- and formamide-denatured and then analyzed on nondenaturing polyacrylamide gels. PCR primer pairs were tested for the capacity to produce SSCP patterns allowing the seven B haplotypes in the MHC B congenic lines, and seven B haplotypes known to be segregating in two commercial broiler breeder lines to be distinguished. Primer pairs were further evaluated for their capacity to reveal the segregation of B haplotypes in a fully pedigreed family and in a closed population. Concordance was found between SSCP patterns and previously assigned MHC types. B-F and B-L SSCP patterns segregated in linkage as expected for these closely linked loci. We conclude that this method is valuable for defining MHC B haplotypes and for detecting potential recombinant haplotypes especially when used in combination with B-G (class IV) typing by restriction fragment pattern.

Three new MHC haplotypes in broiler breeder chickens.

Six distinct serotypes of the chicken B blood group system (which encodes the major histocompatibility complex) were identified in a commercial broiler breeder line (Line C). The B serotypes were compared by B-G restriction fragment length polymorphism (RFLP) analysis, allele-specific PCR typing test for B-LBII family genes and nucleotide sequence analysis of expressed B-F and B-LBII family genes. The results indicated the existence of seven distinct B haplotypes. Nucleotide sequence analysis demonstrated that three of the Line C haplotypes encode new B-F and B-LB alleles.

A PCR method for typing B-L beta II family (class II MHC) alleles in broiler chickens.

Certain haplotypes of the major histocompatibility (B) complex are strongly associated with resistance or susceptibility to several infectious diseases in Leghorn chickens. Identification of chicken haplotypes based on the nucleotide sequence of B complex loci could provide more precise identification of haplotypes than traditional serological methods. We report the development and application of polymerase chain reaction with sequence specific primers (PCR-SSP) to type broiler chicken B haplotypes based on the DNA sequence of B-L beta II family genes. Five well-defined standard B haplotypes from White Leghorns and 12 recently characterized B haplotypes from a broiler breeder line were used to develop the test system. The B-L beta II family loci were amplified from genomic DNA by B-L beta II family specific primers and then characterized by PCR-SSP. In total, ten pairs of primers, derived from the sequences of expressed B-L beta II family alleles, were used in the PCR typing test to discriminate the chicken B haplotypes identified previously by serological means. The PCR-SSP showed that each haplotype had a different amplification pattern, except those haplotypes known or suspected to have the same B-L beta alleles. Cloning and sequencing of the family specific PCR products indicated that two loci in the B-L beta II family, presumably B-L beta I and B-L beta II, were amplified. Finally, B-L beta PCR-SSP typing was used in combination with B-G RFLP analyses to characterize unusual (variant) B serotypes; the results indicate that some of these are natural recombinants within the B complex.

The MHC of a broiler chicken line: serology, B-G genotypes, and B-F/B-LB sequences.

Although the major histocompatibility complex of chickens (encoded in the B complex) has been studied for a number of years, almost all work has focused on the White Leghorn breed. Broiler (meat-type) chickens were derived from other breeds, including Cornish and Plymouth Rock. It was our hypothesis that new B haplotypes, not previously identified in White Leghorns, might be present in lines of broiler chickens. Furthermore, alloantisera used to identify B serotypes in Leghorn lines reportedly do not work well outside the line in which they were raised, with the result that broiler B haplotypes have not been incorporated into the universal nomenclature system. Our approach was to use a panel of B alloantisera produced to identify B serotypes within a commercial broiler breeder line (designated line A). B homozygotes identified serologically were compared by B-G genotyping using restriction fragment length polymorphism analysis. Furthermore, reverse transcription-polymerase chain reaction was used to amplify variable domains of expressed B-LB and B-F genes of homozygotes of most of the B serotypes in Line A, followed by cloning and nucleotide sequence determination. Comparison of B-LB and B-F sequences with standard Leghorn haplotypes demonstrated the existence of new alleles of B-L and B-F in a broiler breeder line, as well as the presence of alleles previously identified in Leghorns. In some cases, Leghorn-type alleles were in linkage with different B-G alleles in the broiler line than the common haplotypic associations found in Leghorn lines.