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Apicomplexan parasites of the genus Eimeria are widespread in poultry flocks and can cause the intestinal disease coccidiosis. Early studies, concerned with intraspecific variation in oocyst morphology, indicated that phenotypic changes may be induced by selection experiments conducted in vivo. Genetic selection driven by targeted selection for specific phenotypes has contributed to our understanding of the phenomenon of drug resistance and the development of live attenuated vaccines. Our present knowledge regarding genetics of Eimeria is largely based upon the utilization of such selected strains as genetic markers. Practical advantages of working with Eimeria spp. in the chicken are discussed. The selection of drug-resistant strains by serial propagation has provided useful information regarding the mechanisms of drug resistance and likely longevity of anticoccidial drugs when introduced in the field. Selection experiments to develop precocious strains of Eimeria and growth in chicken embryos have contributed to the development of safe and effective live attenuated vaccines for the control of coccidiosis. Establishment of protocols for genetic complementation by transient or stable transfection of Eimeria is now supporting direct manipulation of parasite genotypes, creating opportunities to expand the range and value of live parasite vaccines. Procedures for developing drug-resistant and precocious lines of Eimeria and/or genetic markers described here are likely to prove useful for researchers investigating the propensity for resistance development to novel compounds and the development of new attenuated vaccines. Such investigations can be helpful in providing a better understanding of biochemical and molecular aspects of the biology of these parasites. [ABSTRACT FROM AUTHOR]

Three-week-old turkey poults were infected with pure lines of three species of Eimeria (E. adenoeides, E. gallopavonis, and E. meleagrimitis) recently isolated from commercial turkey farms. The lines had been propagated from a single oocyst and identified by species-specific PCR amplification of the mitochondrial cytochrome c oxidase subunit I (COI) gene. Five to six days after infection their intestines were removed and examined for the presence of intestinal lesions. A description and review of the pathology caused by these parasites is provided, and a scoring system developed by which the severity of the lesions can be evaluated. The system is similar to that described by Johnson, J. and Reid, W. M. [1970. Anticoccidial drugs: lesion scoring techniques in battery and floor-pen experiments with chickens. Experimental Parasitology, 28, 30–36] for chickens in which a score of zero to four is assigned to lesions of increasing severity. The intestinal lesions observed here, and their assigned scores, are supported by representative illustrations. It is hoped that they may prove a useful tool for evaluating the pathology caused by E. adenoeides, E. gallopavonis, and E. meleagrimitis in the turkey. RESEARCH HIGHLIGHTS A scoring system has been developed for intestinal lesions caused by three species of Eimeria that infect the turkey. The lesions attributable to these species are illustrated. [ABSTRACT FROM AUTHOR]

Thomas K. Jeffers has made many significant contributions to our understanding of the biology of the parasite Eimeria, the cause of coccidiosis in poultry. His work has had direct practical application for the control of this widespread disease. Topics discussed include Jeffers’ pioneering work concerned with genetics of the host response to infection, the nature of biological and immunological intraspecific variation, drug resistance and discovery, field surveys of resistance, and his most recognized achievement—the demonstration that the lifecycle of coccidia may be altered by artificial selection. Parasites so modified are attenuated but retain their immunogenicity, a discovery that has led to the development of live vaccines that are inherently non-pathogenic. This article provides a brief biography and describes the contributions that Jeffers has made to our knowledge of coccidiosis. [ABSTRACT FROM PUBLISHER]

Metachromatic polyelectrolyte titration was investigated as a means of analyzing polymeric quaternary ammonium salts (polyquaterniums) of relatively low charge density used as ingredients in cosmetics. They are of possible toxicological concern, but little is known of their environmental fate and behavior. With o-toluidine blue as the indicator, determination of the concentration of a range of polyquaterniums of commercial importance and cosmetic origin was possible. Using a visual endpoint, normalities as low as 3 × 10-5 N could be determined, while with a spectrophotometric endpoint, the technique was effective to approximately 3 × 10-6 N. The concentrations (g L-1) to which these normalities correspond depend on the charge density of the polymer. Polyquaterniums are frequently used in association with anionic surfactants in cosmetic formulations and the presence of an anionic surfactant even in excess did not affect results although the color change was less stable. Titration in the presence of prepared humic acid was also possible. [ABSTRACT FROM AUTHOR]

Coccidiosis is a widespread disease of considerable economic importance to the turkey industry, as is evident by the fact that many millions of dollars are spent annually on its control. Despite this, in recent years little research has been conducted on the causative organisms—protozoan parasites of the genus Eimeria. This is unfortunate because current methods of control are not without problems. It is possible, therefore, that in the future optimal productivity in turkey production will be difficult to achieve. There has been no recent comprehensive literature review of coccidiosis in the turkey. In the present article our knowledge of the biology of the species of Eimeria that infect the turkey is critically reviewed. Other topics considered include host specificity, host resistance, acquired immunity, in vitro cultivation, pathology, pathogenicity, clinical signs, diagnosis, epidemiology, prevalence, significance, chemotherapy, drug resistance, drug toxicity, and vaccination. The review is intended to provide a baseline for future studies of this important disease. [ABSTRACT FROM AUTHOR]

The acquisition of immunity by chickens infected 18 h post-hatch with 100 oocysts of Eimeria maxima and reared in floor-pens in contact with their droppings was investigated. In the first experiment, birds were placed on new litter and immunity was measured at 2, 3, 4, and 5 weeks by calculation of weight gain from days 0 to 7 following challenge with 100000 oocysts or by oocyst production in the faeces from days 5 to 8 following challenge with 500 oocysts. In the second experiment, birds were placed on new litter or reused litter from the first experiment (1 week after birds from the first experiment had been removed when 6 weeks of age), and were challenged at 1, 2, and 3 weeks of age. In the first experiment, immunity had developed in birds challenged at 3, 4, and 5 weeks, judged by weight gain and oocyst production, but immunity was not complete at 2 weeks. In the second experiment, immunity had developed in birds challenged at 1, 2, and 3 weeks measured by either criterion. In both experiments, birds produced small numbers of oocysts in their faeces following challenge. Judged by the weight gain following challenge, no significant difference in the acquisition of immunity was observed whether birds were reared on new or reused litter. [ABSTRACT FROM AUTHOR]

A method to quantify induction of vitellogenin (Vtg) mRNA in adult male mosquitofish was developed. Male mosquitofish were exposed to 0, 1, 20 and 250 ng l -1 17β-oestradiol (E 2 ) for 4 and 8 days in static exposures, and liver Vtg mRNA and 18S rRNA expression were quantified in duplex RT-PCR. Liver 18S rRNA expression was very consistent among individuals, and there was a highly significant increase in Vtg mRNA expression after exposure of mosquitofish for just 4 days at 250 ng l -1 E 2 . Lower doses did not induce Vtg mRNA expression even at 4 or 8 days. This method could be used as a rapid test to detect exposure of mosquitofish to oestrogenic chemicals. Further work is needed to determine if increased Vtg mRNA levels in male mosquitofish induce Vtg synthesis, and to determine the usefulness of the method in field sampling. [ABSTRACT FROM AUTHOR]

These guidelines are intended to aid those engaged in poultry research in the design, implementation and interpretation of laboratory, floor-pen and field studies for the assessment of the efficacy and safety of live anticoccidial vaccines for immunization of chickens and turkeys against Eimeria species. In addition to efficacy and safety requirements, manufacture, quality control and licensing considerations are discussed. The guidelines do not address subunit vaccines comprising non-viable material, but many of the principles described will be relevant to such vaccines if they are developed in the future. Guidelines are available in some countries for avian vaccines of bacterial or viral origin but specific standards for anticoccidial vaccines in poultry have not, as far as we know, been produced. Information is provided on general requirements of registration authorities (based upon regulations applicable in the European Union and the USA) for obtaining marketing authorizations for vaccines. These guidelines may assist poultry specialists in providing specific information for administrators involved in the decision-making process leading to registration of new vaccines, and are intended to facilitate the worldwide adoption of consistent, standard procedures. [ABSTRACT FROM AUTHOR]

The Nightmare Intervention & Treatment Evaluation (NITE) Scale is a self-report instrument developed to assess nightmare distress among those diagnosed with posttraumatic stress disorder. This article describes two studies that examine the psychometric properties of this scale. Male and female participants ranged in age from 23 to 84 years and were from diverse ethnic backgrounds. The first study (N = 129) evaluated factor structure and internal consistency. Fifty-three scale items were tested and reduced to a 32-item scale with 24 items measuring nightmare distress, 6 validity items, and 2 frequency items. [ABSTRACT FROM AUTHOR]

Walter T. Johnson (1892 to 1937), veterinarian at Western Washington Agricultural Experiment Station (WWAES), Puyallup, Washington, USA, and subsequently poultry pathologist and professor of veterinary medicine at Oregon State University Agricultural Experiment Station (OSAES), Corvallis, Oregon, USA, made many important contributions to our understanding of the disease coccidiosis. His pioneering work included the first description of Eimeria necatrix and Eimeria praecox from the chicken and identification of four other species of Eimeria from the fowl. He demonstrated the relationship between numbers of oocysts ingested and severity of infection, and described the phenomenon of host specificity and the significance of immunity. Contrary to widespread opinion, he considered that coccidia were not involved in blackhead disease and other pathological conditions reported from the fowl. His views on control were ahead of his time and he anticipated the possibility of vaccinating birds by infecting them with live oocysts. In addition to his studies of coccidiosis, Johnson introduced a vaccine for fowlpox and ran a pullorum-testing laboratory. He produced numerous articles of an advisory nature on a diverse range of topics concerned with poultry and cattle. Much of Johnson's research was published in bulletins of the WWAES and OSAES that are not widely available and consequently have often been overlooked by the scientific community. Following his premature death, the director of OSAES claimed, "more information on the parasitic disease coccidiosis has been discovered at the Oregon Station than at almost any other place. The Oregon Station is probably the only institution in the world where six known species of coccidia of the chicken are available in pure culture" ( Anonymous, 1938a ). This is a claim that few institutions can match today. [ABSTRACT FROM AUTHOR]

The practical synthesis of a mixed phenoxy-amidate derivative of PMPA with high oral bioavailability and favorable pharmacokinetics is described. The non-stereoselective synthetic route produces a 1:1 mixture of two diastereomers at phosphorous. Simulated moving bed chromatography using Chiralpak AS enabled kilo-scale isolation of the more potent diastereomer (GS-7340). The GS-7340 phosphorous chiral center was found to be (S) by X-ray crystallography. [ABSTRACT FROM AUTHOR]

The diastereomers of GS-7171, aryl phosphoramidate derivatives of the anti-HIV nucleotide analog 9-[2-R-(phosphonomethoxy)propyl]adenine (tenofovir, PMPA), were isolated by batch elution chromatography and continuous simulated moving bed chromatography. The absolute configuration of the more pharmacologically active diastereomer, GS-7340, was determined to be (R,S,S) by single crystal x-ray crystallography. [ABSTRACT FROM AUTHOR]

The long-held view that anticoccidial drugs, to a greater or lesser extent, interfere with the development of immunity to Eimeria species may no longer be correct because few drugs, if any, are capable of preventing some degree of parasite multiplication. Acquisition of immunity is, therefore, a real possibility, providing sufficient parasites are present in the environment. Immunity is an important consideration during the rearing of replacement layers, broiler breeders, turkeys, and gamebirds, but little research has been carried out on the effects of drugs on immunity development in these categories of stock. In recent years, there has been a change in the perception of the significance of immunity in broilers, and some broiler producers have taken this into consideration when designing drug programs for use in the field. Studies in floor pens and the field indicate that broilers given various drug programs can develop immunity when exposed to natural infections but that this process takes time: solid immunity not developing until birds are 6 to 7 weeks of age. This suggests that drugs should not be withdrawn from the feed prematurely since birds may not have had time to develop adequate immunity. [ABSTRACT FROM AUTHOR]

The acquisition of immunity to Eimeria species was studied in broilers reared in floor-pens on new and used litter, and given different anticoccidial drug programmes. Programmes included a single drug (synthetic compound or ionophore) given in the starter and grower feed, or 'shuttle' programmes comprising a synthetic drug followed by an ionophore (or vice versa) given in the starter and grower feeds, respectively. None of the drug programmes prevented parasite multiplication, since oocysts were found in the intestines of birds and in the litter. Birds were challenged at weekly intervals with a mixture of species (E. acervulina, E. maxima and E. tenella) in order to establish whether protective immunity had developed. Birds reared on used litter that received no medication acquired immunity by 5 weeks, whereas birds reared on new litter were not fully protected against a challenge inoculum until 7 weeks of age. Apart from birds given an ionophore followed by a synthetic drug, medicated birds developed immunity by 7 weeks, irrespective of the type of drug programme, or whether they had been reared on new or used litter. Birds reared in commercial houses (where one and seven previous flocks had been raised) and given a synthetic drug followed by ionophores, also developed immunity to Eimeria species. Immunity was acquired more rapidly to E. maxima than E. acervulina or E. tenella. [ABSTRACT FROM AUTHOR]

Proposes to set aside the material of real life and look at how the pictorial evidence of Jan Steen's own presentation of self helped forge the identity Arnold Houbraken constructed for him. Houbraken as interpreter of seventeenth-century Dutch pictorial practices and artistic personalities; Artist's legendary image as proto-bohemian saturnalian profligate; Accounts on Houbraken and Steen.

Acknowledges the colleagues of "The Art Bulletin" outgoing editor-in-chief H. Perry Chapman who contributed to the success of the journal. Staff of the magazine; Articles featured in the magazine.

Introduces exhibition review articles and state of the discipline essays, two features added to the `The Art Bulletin' journal in year 2001. Role of museum exhibitions in art historical scholarship; Aim of the state of the art essays.

Talks about the history and mission of the `Art Bulletin.' Efforts to make the magazine more readable; Process that unsolicited articles undergo before they are published.