Protection by a commercial Arkansas-type infectious bronchitis virus vaccine against a field isolate of the same serotype

A late-breaking infectious bronchitis virus (IBV)-associated respiratory disease was a chronic problem in Georgia broilers in 1995. The predominant virus isolated from diseased birds was the Arkansas (Ark) type of IBV. Because broilers in Georgia are currently vaccinated with the Arkansas serotype, there was concern that a phenotypic and/or genotypic change had occurred in the field virus so it could break through immunity conferred by commercial vaccines. The purpose of this study was to determine if a commercially available vaccine for IBV as currently used in the field still protected broilers against those viruses. We obtained 108 1-day-old broilers from a commercial source and assigned them randomly to 12 groups. One-half of the groups of birds were vaccinated at 1 day of age and again at 18 days of age with commercially available B1/Mass/Ark vaccine. One-half of both vaccinated and nonvaccinated groups of birds were challenged at 35 and 42 days of age with a recent IBV Ark field isolate. Serologic titers were evaluated by enzyme-linked immunosorbent assay at time of challenge and at the end of the trial. A necropsy was performed on birds at 56 days and pathogenicity was assessed. Seroconversion was statistically significant in all birds exposed to vaccine or challenge by 56 days of age. Gross airsacculitis was significantly more severe in broilers challenged without prior exposure to vaccine.     

Bone morphogenetic protein 6 in skeletal metastases from prostate cancer and other common human malignancies

Prostatic adenocarcinoma commonly metastasizes to bone. Unlike most other bony secondaries, the majority of skeletal prostatic metastases are osteoblastic rather than osteolytic in nature. Several growth factors which are known to stimulate bone formation are expressed in benign and malignant prostate cells, but none has been specifically linked to osteosclerotic metastases. Bone morphogenetic proteins (BMPs) induce ectopic bone formation in vivo. We have reported previously that BMP-6 mRNA and protein are expressed in the majority of primary prostatic carcinomas with established skeletal metastases but rarely in clinically organ-confined tumours. This study examines the expression of BMP-6 mRNA in matched prostatic primary and secondary bony lesions and in isolated skeletal metastases from prostatic adenocarcinomas, as well as other common human malignancies, by in situ hybridization. BMP-6 mRNA was detected in 11 out of 13 bone metastases from prostate carcinoma and in three paired samples of primary prostate carcinoma and matching skeletal metastasis. Weak signals for BMP-6 were also present in 5 out of 17 skeletal deposits from non-prostatic malignancies. BMP-6 mRNA appears to be strongly expressed in prostatic adenocarcinomas, both in the primary tumour and in bone metastases. It is also expressed, though less frequently, in skeletal metastases from other human carcinomas. Our findings suggest that BMP-6 may hold potential as an attractive marker and possible mediator of skeletal metastases, particularly in prostate carcinoma.     

Damage to urban infrastructure and other public property from the 1989 Loma Prieta (California) earthquake

This research project investigated the damage to public property caused by the 1989 Loma Prieta earthquake. The claims filed by state and local governments, special districts and non-profit organizations under the Federal Emergency Management Agency's (FEMA) disaster assistance program were analyzed to understand better the pattern of damage caused by the earthquake. These claims accounted for nearly $600 million. The damage distribution was very skewed with eleven agencies claiming more than 70 per cent of this total. Non-profit agencies accounted for a surprisingly large portion of overall damage. Heavy damage was concentrated in relatively few areas. The extent of damage in an area was a function of concentration of property, site conditions, characteristics of building stock, and distance from the epicenter.     

A novel protein modification pathway related to the ubiquitin system

Ubiquitin conjugation is known to target protein substrates primarily to degradation by the proteasome or via the endocytic route. Here we describe a novel protein modification pathway in yeast which mediates the conjugation of RUB1, a ubiquitin-like protein displaying 53% amino acid identity to ubiquitin. We show that RUB1 conjugation requires at least three proteins in vivo. ULA1 and UBA3 are related to the N- and C-terminal domains of the E1 ubiquitin-activating enzyme, respectively, and together fulfil E1-like functions for RUB1 activation. RUB1 conjugation also requires UBC12, a protein related to E2 ubiquitin-conjugating enzymes, which functions analogously to E2 enzymes in RUB1-protein conjugate formation. Conjugation of RUB1 is not essential for normal cell growth and appears to be selective for a small set of substrates. Remarkably, CDC53/cullin, a common subunit of the multifunctional SCF ubiquitin ligase, was found to be a major substrate for RUB1 conjugation. This suggests that the RUB1 conjugation pathway is functionally affiliated to the ubiquitin-proteasome system and may play a regulatory role.     

The common infectious diseases in Australia. A report from the australian general practitioner morbidity and prescribing survey

A study of the common infectious diseases occurring in Australia during 1969 to 1973 showing the total patient-doctor contact for these diseases, the contact rate per episode and the estimated annual new cases seen is presented. In addition, the frequency by age-group and comments made on annual variations, sex differences (where applicable) and the treatment ordered by a large panel of general practitioners are shown.     

Sequence analysis of the terminal protein precursor coding regions from bovine adenovirus serotypes 2 and 3

The acceptability of medical abortion (mifepristone and misoprostol) among US women was investigated in a 1995 survey of 262 women seeking this method of pregnancy termination at 3 clinics in Oregon, Washington, and Vermont. The abortion patients' mean age was 27 years; mean gestational age was 49.5 days. 51.1% of respondents had experienced at least one prior abortion. Women completed a questionnaire at their initial clinic visit and again two weeks after the procedure. Participants chose medical abortion to avoid surgery (62.8%) or because they perceived it to be less invasive (56.3%), more natural (40.5%), and associated with a lesser risk of infection or damage to the uterus (35.1%) than vacuum aspiration, and could be performed earlier in pregnancy (27.2%). 49.8% indicated they preferred to wait for abortion to occur with a partner, friend, or family member, while 30.6% preferred to be alone; only 17.6% wanted to wait with other women undergoing the same procedure. Comparison of pre- and post-abortion questionnaires indicated women expected significantly more discomfort than they actually experienced and underestimated the number of days of bleeding. 72.8% of respondents were very satisfied with their medical abortion and 15.5% were somewhat satisfied. Women in the somewhat satisfied group had experienced significantly more abortion-related discomfort and anxiety than those who were very satisfied. Prior abortion experience and demographic characteristics did not influence satisfaction. 94% stated they would recommend medical abortion to a friend and 87% would select medical abortion if they had to terminate another pregnancy. Medical abortion has the potential to increase access to abortion among underserved groups of US women. Appropriate educational materials should be developed to help women choose between abortion methods.     

Structural polymorphism of the RecA protein from the thermophilic bacterium Thermus aquaticus

The Escherichia coli RecA protein has served as a model for understanding protein-catalyzed homologous recombination, both in vitro and in vivo. Although RecA proteins have now been sequenced from over 60 different bacteria, almost all of our structural knowledge about RecA has come from studies of the E. coli protein. We have used electron microscopy and image analysis to examine three different structures formed by the RecA protein from the thermophilic bacterium Thermus aquaticus. This protein has previously been shown to catalyze an in vitro strand exchange reaction at an optimal temperature of about 60 degrees C. We show that the active filament formed by the T. aquaticus RecA on DNA in the presence of a nucleotide cofactor is extremely similar to the filament formed by the E. coli protein, including the extension of DNA to a 5.1-A rise per base pair within this filament. This parameter appears highly conserved through evolution, as it has been observed for the eukaryotic RecA analogs as well. We have also characterized bundles of filaments formed by the T. aquaticus RecA in the absence of both DNA and nucleotide cofactor, as well as hexameric rings of the protein formed under all conditions examined. The bundles display a very large plasticity of mass within the RecA filament, as well as showing a polymorphism in filament-filament contacts that may be important to understanding mutations that affect surface residues on the RecA filament.     

A polymorphism in a DNA polymerase alpha gene intron differentiates between murine virulent and avirulent strains of Toxoplasma gondii

The IC intron, found within the DNA polymerase alpha gene of Toxoplasma gondii, was used to evaluate the genetic relationship among 10 strains of T. gondii. Sequence comparison detected polymorphisms within this 652 bp intron which correlated with murine virulence. The results reported here suggest that T. gondii contains two lineages, corresponding with their virulence, evolving independently following their separation. The extensive homology of the IC sequences within the virulent and avirulent groups affirms the close relationship of the strains within the group, as reflected by the identical nucleotide substitutions and dinucleotide insertions/deletions observed. In addition, the presence of the Nde I restriction enzyme site within the IC intron of avirulent strains allows definition of a T. gondii strain as murine virulent or avirulent without needing to test it in vivo.     

A single genetic origin for the common prothrombotic G20210A polymorphism in the prothrombin gene

The polymorphism G20210A in the 3' untranslated region of the prothrombin gene is associated with an increased level of factor II activity and confers a twofold to fivefold increase in the risk for venous thromboembolism. Among Caucasian populations, the prevalence of factor II G20210A heterozygotes is 1% to 6%, whereas in non-Caucasian populations it is very rare or absent. The aim of the present study was to discern whether factor II G20210A originated from a single or recurrent mutational events. Allele frequencies of four dimorphisms spanning 16 of 21 kb of the factor II gene were determined in 133 unrelated Caucasian subjects of Jewish, Austrian, and French origins who bore factor II G20210A (10 homozygotes and 123 heterozygotes) and 110 Caucasian controls. Remarkable differences in the allele frequencies for each dimorphism were observed between the study groups (P = .0007 or less), indicating strong linkage disequilibrium and suggesting a founder effect. Indeed, a founder haplotype was present in 68% of 20210A mutant alleles and only in 34% of 20210G normal alleles (P < .0001). These data strongly support a single origin for factor II G20210A that probably occurred after the divergence of Africans from non-Africans and of Caucasoid from Mongoloid subpopulations.     

A fish encephalitis virus that differs from other nodaviruses by its capsid protein processing

RNA2, the short segment of the genome of Dicenthrarchus labrax encephalitis virus (DIEV), a fish nodavirus causing seabass encephalitis, was cloned. Sequence analysis revealed that DIEV RNA2 contains a single open reading frame (ORF), which carries the catalytic D-75 residue but lacks the site for autocatalytic proteolysis, the process yielding the two capsid proteins of insect nodaviruses. Nevertheless, SDS-PAGE analysis of mature virions revealed a 43-45 kDa protein doublet. In order to determine the mechanism of synthesis of the two capsid proteins in DIEV, wild type and mutagenized forms of RNA2 were expressed in cell-free translation extracts and in transfected cells. Results showed that, despite the presence of the catalytic D-75 residue, the DIEV capsid protein doublet did not result from the assembly-dependent autocatalytic cleavage of a protein precursor. Moreover, our data show that, although suggested by sequence analysis, the DIEV capsid protein doublet results from neither an alternative initiation codon usage nor from a--1 ribosomal frameshift. Results of cell-free translation experiments demonstrate that the capsid protein doublet neither results of the proteolytic cleavage of a precursor nor of a degradation process. Kinetics of capsid protein synthesis in cell-free translation programmed with RNA2 revealed, instead, that the two capsid proteins are cosynthesized. Together these data strongly suggest that the DIEV capsid protein doublet results from cotranslational modification(s) of the ORF-encoded protein.     

荆门市常见传染病季节性分布特征动态分析

目的 分析荆门市常见传染病发病的季节性分布特征与流行规律,为制定和调整传染病的防制策略和措施提供科学依据.方法 采用集中度和圆形分布法进行季节性分析,按照控制图法预警模型原理,对2000-2009年的分月发病情况进行评价.结果 荆门市常见传染病中乙型脑炎有严格的季节性,麻疹、疟疾有明显的季节性,痢疾、伤寒有一定的季节性,甲型病毒性肝炎、肺结核、乙型病毒性肝炎、淋病季节性较差;麻疹、疟疾、痢疾的季节性呈逐年降低下降趋势,发病高峰日呈逐年提前趋势;麻疹、梅毒的发病态势不稳定.结论 针对不同传染病的季节性分布特征需采取不同的控制措施.     

The carboxyl-terminal 120-residue polypeptide of infectious bronchitis virus nucleocapsid induces cytotoxic T lymphocytes and protects chickens from acute infection

Specific cytotoxic T-lymphocyte (CTL) responses to nucleocapsid of infectious bronchitis virus (IBV) were identified by using target cells infected with a Semliki Forest virus (SFV) vector. Effector cells for CTL assays were collected from chickens infected with the Gray strain of IBV or inoculated with a DNA plasmid encoding nucleocapsid proteins. IBV-specific CTL epitopes were mapped within the carboxyl-terminal 120 amino acids of the nucleocapsid protein. CTL lysis of target cells infected with SFV encoding nucleocapsid was major histocompatibility complex restricted and mediated by CD8+ T cells. In addition, splenic T cells collected from chickens inoculated in the breast muscle with a DNA plasmid encoding this CTL epitope(s) recognized target cells infected with wild-type virus or an SFV vector encoding nucleocapsid proteins. CTL activity of splenic T cells collected from chicks immunized with a DNA plasmid encoding CTL epitopes was cross-reactive, in that lysis of target cells infected with serologically distinct strains of IBV was dose responsive in a manner similar to that for lysis of target cells infected with the homologous strain of IBV. Furthermore, chickens immunized with a DNA plasmid encoding a CTL epitope(s) were protected from acute viral infection.     

Embryo vaccination of chickens with infectious bronchitis virus: histologic and ultrastructural lesion response and immunologic response to vaccination

The present study examined the effects of instruction type and boredom proneness (BP) on vigilance performance, workload, and boredom. Subjects completed the Boredom Proneness Scale and were assigned to high and low groups based on their scores. They then monitored a VDT for critical signals. Half the subjects were instructed to detect "critical" flickers (detection emphasis), and the remaining subjects were instructed to relax but to respond to any flickers observed (relaxation emphasis). Subjects also provided pre- and postvigil ratings of workload, stress, and boredom. A performance decrement was observed for all conditions. Low-BP subjects outperformed high-BP subjects and reported less boredom. Thus the results from the present study provide evidence for the long-sought, elusive link between trait boredom and performance in vigilance. In addition, subjects who received relaxation-emphasis instructions reported lower workload, frustration, and stress for the vigil than did those receiving detection-emphasis instructions. These results are discussed in terms of a recent dynamic model of stress as it relates to sustained attention.