bluuebunny/crossref_metadata_2025 huggingface dataset:
Local and Cosmopolitan Physicians*
Authors: Hetherington Robert W.
Published: January 2009

La theorie du localisme‐cosmopolitanisme est appliquee a l'identification des types de medecin. L'analyse factorielle, le coefficient de concordance de Kendall ainsi que les gamma et chi‐carres sont utilises selon diverses combinaisons pour identifier des constellations de variables. On identifie deux types de medecins qui sont statistiquement bien differencies: le professionnel de la medecine (cosmopolitain) et le politicien de la medecine (local). Une demonstration empirique s'ensuit laquelle etablit que les cosmopolitains ont une attitude plus liberate que les locaux vis‐a‐vis les problemes sociaux et medicaux et une attitude plus critique vis‐a‐vis les regimes d'assurance maladie.

The theory of localism‐cosmopolitanism is applied to the identification of physician‐types. Factor analysis, Kendall's coefficient of concordance, gamma and chi‐square are used in combination to identify variable clusters. Two statistically distinct types were found, the professional (cosmopolitan) and the medical politician (local). Empirical evidence is presented which indicates that cosmopolitans tend to be more liberal than locals in attitudes toward certain medical‐social issues, and more critical of health insurance plans.
Structure and Randomness in a Juvenile Legal System*
Authors: Tepperman Lorne
Published: January 2009

Est‐ce que les evenements dus au hasard sont des erreurs qui demontrent le caractere inadequat d'une explication sociologique, d'une prediction ou d'un plan ou s'ils appartiennent a des structures conferant ainsi au sociologue des pouvoirs predictifs additionnels ? On demontre qu'un systeme legal pour adolescents est fonctionnel en autant qu'on utilise sa propre definition de TefBcacite. Cependent, une simulation au hasard indique que ce niveau de succes ne depasse pas une efficacite aleatoire. Au moment de planifier ou d'e valuer des organisations, les sociologues doivent identifier les effets du hasard sur l'efficacite globale du systeme avant de chercher a expliquer son niveau d'efficacite en tenant compte des variables causales habituelles, soit des variables physiques, psychologiques et sociales. Si on ne se plie pas a cette exigence on surestimera les facteurs explicatifs de l'efficacite et on risquera de ne pas etre en mesure de predire ou de produire les resultats escomptes.

Are random events merely “errors” demonstrating the inadequacy of a sociological explanation, prediction or plan or are they structured, thus providing the sociologist with additional predictive powers? A juvenile legal system is shown to be successful within its own definition of effectiveness; however a random simulation suggests that this degree of success does not exceed random effectiveness. Sociologists must, in planning or evaluating organizations, partial out the contributions of randomness to the total effectiveness of the organization before attempting to explain success in terms of the usual “causal” ‐ physical, psychological and social ‐ variables. Failure to do so will result in “over‐explanations” of success which may fail to predict or produce desired outcomes.
Recent Trends in Canadian Fertility*
Authors: Henripin Jacques , Legare Jacques
Published: January 2009

Depuis 1941, on a observe au Canada des variations importantes du niveau de la fecondite et la tendance est souvent illustree par les fluctuations du taux de natalite. Afin de mieux interpreter ces fluctuations, une analyse des principales composantes du taux de natalite s'avere necessaire: la distribution par age de la population feminine (mariee ou de tout etat matrimonial) et les taux de fecondite par age tant pour les femmes mariees que pour l'ensemble des femmes. C'est la baisse de la fecondite legitime qui est en majeure partie la cause de la chute du taux de natalite observee depuis 1959. Pour approfondir l'analyse, on etablit une comparaison entre des indices de fecondite legitime de cohorte et du moment. De 1946 a 1960, les indices du moment sont nettement plus eleves que ceux de cohorte; cependant contrairement a ce qui s'est passe au cours de cette periode, on observe maintenant un etalement des intervalles entre naissances, de telle sorte que depuis 1960, les indices du moment sont nettement plus faibles que les indices de fecondite legitime de cohorte.

Observers have witnessed important changes in the level of fertility in Canada since 1941. The trend is often illustrated by variations in the birth rate. To understand these variations better, the main components of the birth rate will be analysed: age distribution of total and married female population, and age‐specific fertility rates for all women and married women. The decline of marital fertility is mostly responsible for the fall of the birth rate observed since 1959. In a further analysis, period and cohort marital fertility are compared: from 1946 to 1960, period measures were much higher than cohort measures; in contrast to what happened during those years we now observe a spread in birth intervals, so that, since 1960, period measures are much lower than cohort marital fertility measures.
Contradiction and Change of Performance Expectations*
Authors: Foschi Martha
Published: January 2009

L'auteur propose deux hypotheses pour justifier le fait que les anticipations de ≪ performance ≫ changent lorsqu'elles sont mises en présence de faits objectifs qui les contredisent. On peut prédire que ce changement dans les anticipations evolue en fonction de la variété et du niveau des contradictions. Le cas de celui dont les attentes pour soi sont inferieur aux attentes pour les autres est utilise pour des fins expérimentales de verification des hypothèses. A la fin de l'article l'auteur apporte des suggestions dans le but d'améliorer l'arrière‐plan théorique des hypothèses.

Two hypotheses are proposed on the way specific performance expectations change when confronted with objective evidence that contradicts them. The change in expectations is predicted to be a function of the number and the degree of the contradictions they receive. The case of initial lower expectations for self than for other is used in an experimental test of the hypotheses, and these are confirmed by the results of the test. Some suggestions for the refinement of the hypotheses' theoretical background are discussed at the end.
Aspects of Family Formation in Canada*
Authors: POOL D. IAN , BRACHER M.D.
Published: January 2009

La fécondité est en déclin au Canada. Nous tentons d'expliquer ce changement, et d'en dégager les implications pour la formulation de politiques. Nous faisons la critique des études canadiennes récemment publiées sur la question en les situant par rapport à une adaptation du cadre de référence Davis et Blake. Ceci nous permet de formuler des hypothèses relatives à deux niveaux dont la distinction est implicite dans le cadre de référence: (1) le niveau de la structure sociale (variables indépendantes), (2) le niveau des phénomènes qui déterminent plus directement la fécondité (variables “intermédiaires”). Les données disponibles nous permettent de vérifier nos hypothèses. Un problème demeure cependant: le déclin de la fécondité est‐il lié au fait qu'on veut limiter les naissances ou les différer?

Fertility is declining in Canada. We attempt to account for this change and to suggest policy implications. We review recent Canadian studies fitting them into an adaptation of the Davis‐Blake framework. This permits the formulation of hypotheses at two levels implicit in the framework: (1) social structural (independent variables); (2) proximate (“intermediate” variables). Hypotheses were tested against available data, but a problem remained: does the decline result from deferring or averting of births?
Modernization and Fertility: The Case of the James Bay Indians*
Authors: ROMANIUK A.
Published: January 2009

II a été souvent avancé, mais sans preuve empirique suffisante, que le processus de modernisation peut s'accompagner, à son stade initial, d'une augmentation du taux de fécondité, notamment grâce au relâchement des contraintes traditionnelles qui affectent la procréation. Les données d'une enquête auprès des Indiens de la Baie James semblent corroborer la théorie. En effet, elles révèlent que les intervalles intergénésiques diminuent au fur et à mesure qu'on passe des générations plus anciennes aux générations plus récentes des méres indiennes. Trois facteurs, reliés au processus de modernisation, semblent avoir contribuéà ce phénomène: (1) changement dans les habitudes d'allaitement dans le sens d'une réduction de la période ou même d'un abandon de l'allaitement naturel; (2) réduction des accidents puerpéraux, intervenue à la suite des progrès médicaux et du passage du nomadisme à un mode de vie plus stable de la société indienne dans cette région; (3) diminution des incidences des séparations prolongées des époux dans la mesure où s'améliorent les communications entre les villages et la société indienne tend à devenir sédentaire.

The theory that modernization at its initial stage may result in an increase in fertility through the relaxation of restrictive customs governing procreative behaviours of premodern societies has often been postulated, but little empirical evidence has been provided to support it. Data collected on fertility for Indians living in the James Bay area of Canada tend to confirm the validity of this theory. They reveal, for this population, that intervals between successive births tend to become shorter among younger as compared to older generations of mothers, and this is attributed to three factors related to modernization: (1) changes in lactation habits whereby an increasingly larger proportion of mothers either do not breast‐feed at all, or do so for shorter periods of time than did the older generations; (2) reduction in the level of pregnancy wastage resulting both from medical progress and from the fact that hardship and pregnancy accidents to which the pregnant mothers were formerly exposed probably have diminished as James Bay Indians have shifted from a nomadic to a sedentary society; and (3) reduction in the incidence of prolonged temporary separation of spouses as the communication between home villages of spouses has improved and as Indian families have given up their nomadic mode of life.
Unemployment and occupational aspirations: a panel study of high school graduates*
Authors: EMPSON‐WARNER SUSAN , KRAHN HARVEY
Published: January 2009

La plupart des études des aspirations professionnelles des jeunes ont analysé les rapports entre divers facteurs et les aspirations sans chercher à déterminer comment ces aspirations pourraient évoluer au fur et à mesure que les adolescents font la transition entre l'école et le marché du travail. Compte tenu de la situation sur le marché du travail au Canada, les grandes aspirations en matière de carrière de beaucoup de jeunes risquent fort d'être déçues. Les données d'une étude àéchantillon constant chez des jeunes qui avaient terminé leurs études secondaires dans une grande ville de l'Ouest indiquent que l'expérience du chômage au cours de la première année après le départ de l'école conduit à une modération des aspirations profcssionnelles. En examinant ces données, les auteurs cherchent àélucider certaines des grandes questions théoriques touchant la reproduction des inégalités socialcs.

Studies of young people's occupational aspirations have typically focussed on their correlates, but have not addressed the question of how aspirations may be modified as teenagers make the transition from school to work. Given the distribution of jobs in the Canadian labour market, many of the high career aspirations of teenagers will not be satisfied. Data from a panel study of high school graduates in a large western Canadian city show how the experience of unemployment in the first year following graduation leads to a reduction in occupational aspirations. These findings are discussed with reference to central sociological questions about the reproduction of social inequalities.
Some advantages of Canadian disunity: how Quebec sovereignty might aid economic development in English‐speaking Canada*
Authors: BRYM ROBERT J.
Published: January 2009

Les conflits relatifs au partage des pouvoirs entre de grandes communautés ethniques possédant chacune un ensemble complet d'institutions peuvent aboutir à une décentralisation telle que l'État cesse d'être un instrument efficace de planification économique et que l'économie du pays commence à en souffrir. Le cas de tiraillements Canado‐québécois illustre ce type de processus et soulève la question suivante: l'avenir économique du Canada ne serait‐il pas plus prometteur si le Québec devenait indépendant?

Jurisdictional disputes between large, institutionally complete ethnic communities in a single society may promote so much decentralization of authority that the state becomes ineffective as an economic planner. Economic decline may result. The Canada/Quebec case illustrates this process and suggests that Quebec independence may improve Canada's economic prospects.
Trends in the ethnic origins of Canadian elites: the decline of the BRITS?*
Authors: OGMUNDSON R. , MCLAUGHLIN J.
Published: January 2009

Depuis la publication de La mosaïque verticale de John Porter en 1965, la vision préominante du Canada est celie d'un pays caractérisé par une forte stratification ethnique, surtout au niveau des élites, qui seraient elles‐mêmes dominées de façn érasante par des personnes d'origine britannique. Or, des recherches ultérieures sur l'ensemble de la population canadienne démontrent que la stratification ethnique est moins marquée qu'on le croyait; au contraire, elle est plutôt faible et tend même à s'estomper. D'où l'intérêt de reprendre l'analyse des élites canadiennes. L'auteur de cette communication présente les données originales de Porter, fait la synthèse des résultats d'autres recherches pertinentes et décrit les données les plus récentes sur l'évolution des origines ethniques des élites au Canada.

The conventional wisdom concerning ethnicity in Canada has been dominated by the imagery of The Vertical Mosaic published in 1965 by John Porter. This conventional wisdom maintains that Canada is characterized by pronounced ethnic stratification especially at the level of elites which are thought to be dominated overwhelmingly by those of British origin. Suhequent research at the level of the general population has shown that ethnic stratification was not aa great as originally thought, is minimal, and is in decline. Consequently it is of interest to re‐examine the situation regarding Canadian elites. The original data of Porter are presented. The findings of other relevant research are outlined. New data on trends in the ethnic origins of Canadian elites are reported.
Women against feminism: an examination of feminist social movements and anti‐feminist countermovements
Authors: STEUTER ERIN
Published: January 2009

Cette communication se veut une analyse descriptive à la fois des mouvements sociaux féministes aux États‐Unis et au Canada et des contre‐mouvements anti‐féministes qu'ils ont suscités. L'auteur documente la relation dialectique qui caractèrise ces mouvements depuis un siècle din de mieux élucider la nature et le caractère des deux groups. Une attention particulière est accordée au rôle du mouvement pro‐famille au Canada dans l'opposition aux objectifs du mouvement féministe contemporain. L'auteur démontre qu'il s'est créé un rapport d'interdépendance entre les deux camps, qui ont formulé des programmes, des idéologies et des stratégies de plus en plus élaborées à mesure que la lutte pour l'hégémonie s'est intensifiée.

This paper examines feminist social movements in both the United States and Canada and describes and analyses the anti‐feminist countermovements that have repeatedly arisen in response to them. The dialectical relationship that has existed between these movements for the last century is documented in an effort to further understand the nature and character of these two groups. Specific attention is paid to the role of the pro‐family movement in Canada in opposing contemporary feminist goals. It is shown that an interdependence has developed ‐ with the formulation of sophisticated programs, ideologies and strategies on both sides ‐ as the struggle for dominance has intensified.
Falling behind: The income of lone‐mother families, 1970–1985
Authors: MCQUILLAN KEVIN
Published: January 2009

Cette communication analyse la situation économique des familles monoparentales dont le chef est une femme à partir de données des recensements canadiens de 1971, 1981 et 1986 disponibles sur microfiches à accès public. L'analyse révèle qu'en dépit d'une augmentation sensible du revenu réel des familles à mère sans coqjoint, l'écart entre le revenu de celles‐ci et le revenu des familles biparentales s'est creusé de manière importante au cow de la période étudiée de 15 ans. Bien que l'augmentation des salaires aient été lente autant pour hommes mariée que pour les mères sans conjoint, une forte hausse du taux de participation des femmes mariées à la population active a permis aux familles biparentales d'augmenter de façon appréciable leur revenu familial total. Du cǒté des familles à mère sans conjoint, par contre, divers changements démographiques ont limité l'augmentation des gains totaux et ralentit l'accroissement du revenu familial.

This paper examines the economic fortunes of lone‐mother families using the public use microfiles of the 1971 and 1986 Canadian censuses. The analysis shows that despite a 16 per cent increase in the real income of lone‐mother families, the income gap between lone‐mother and two‐parent families widened appreciably over the 15‐year period. Although real wages for both husbands and lone mothers rose slowly, a sharp increase in the labour force participation rate of married women allowed two‐parent families to increase their total family income significantly. By contrast, demographic changes among lone‐mother families served to limit the increase in total family earnings and slowed the rise of family income.
Critical Perspectives in Antiracism: An Introduction*
Authors: Dei George J. Sefa
Published: January 2009

Ce numéro spécial de la RCSA est consacré aux nouvelles façons d'aborder la lutte antiraciste dans des contextes multiraciaux. Les auteurs examinent les pratiques antiracistes selon des points de vue différents qui parfois se chevauchent, et tracent les grandes lignes de la pratique antiraciste, tout particullièrement en ce qui concerne la pédagogie et les ateliers antiracistes. Ils apportent leur contribution à létude de l'antiracisme critique et à son application dans le discours pédagogique. Il est question également dévolution sociale et pédagogique, et ils montrent comment le discours et la pratique anti‐racistes peuvent l'accélérer. Même si les fondements théoriques et méthodologiques de l'antiracisme ne sont pas entièrement définis, les auteurs s'efforcent de reformuler l'antiracisme à partir de ses origines propres. Le présent article amorce la discussion en fixant les limites du discours et en précisant l'impact de l'antiracisme sur lévolution pédagogique et sociale. Il examine comment une culture antiraciste peut sépanouir, surtout dans un contexte eurocanadien et euroaméricain. Les répercussions de la mondialisation sur léducation et lévolution sociale sont examinées, tout comme le sont les motifs de ceux qui préconisent une mise en pratique de la pensée antiraciste.

This special issue of the CRSA aims to explore new ways of thinking about antiracism praxis in multiracial contexts. The papers in this issue examine antiracism praxis from varying and intersecting backgrounds and positions. They present a broad view of antiracism extending from teacher education to antiracism workshop training. They build on existing scholarship in critical antiracism as a pedagogical discourse and a communicative and political practice. A key question is: How we can ensure that antiracism discourse and practice connect to achieve educational and transformative social change? While the theoretical and methodological underpinnings of antiracism are still in the formative stage, the essays will add to ongoing attempts to (re)conceptualize antiracism from its original formulations. This article begins the dialogue by specifying an antiracism discursive framework and the implications of anti‐racism's basic tenets for transformative learning and social change. It explores some of the ways that antiracism knowledge can be constructed, produced and disseminated, particularly (but not exclusively) in Euro‐Canadian/American contexts, and highlights some of the challenges that current globalization processes provide for education and social change, and the rationale for engaging in antiracism praxis.
The Impact of Movements: Bureaucratic Insurgency, Canadianization and the CSAA*
Authors: CORMIER JEFFREY J.
Published: January 2009

Une plus grande attention est actuellement portée aux conséquences des mouvements sociaux. Basé sur du matériel d'archives et d'entrevues, cet article réexamine la notion d'insurrection bureaucratique de Zald et Berger afin d'analyser la dynamique de changement et de transformation de la Société canadienne de sociologie et d'anthropologie (SCSA) au début des années 1970. Contrairement à la thése de Weber‐Michels, qui prédit qu'en gagnant en maturité une organisation tend à devenir moins politisée et plus conservatrice, la SCSA s'est politisée par suite du mouvement de « canadianisation » des institutions culturelles et éducationnelles. Une explication pour ce changement est proposée, laquelle questionne la thèse de transformation organisationnelle de Weber‐Michels et les conséquences qui en découlent.

Greater attention is now being given to the consequences of social movements. Relying on archival and interview material, this paper revisits Zald and Berger's notion of bureaucratic insurgency to analyse the dynamics of change and transformation in the Canadian Sociology and Anthropology Association (CSAA) during the early 1970s. Contrary to the Weber‐Michels thesis, which predicts that as organizations age they become less political and more conservative, the CSAA became politicized as a result of the movement to Canadianize cultural and educational institutions. An explanation for this change is offered, which serves to challenge the Weber‐Michels thesis of organizational transformation and its outcome.
Small Town, Big Benefits: The Ripple Effect of 7/day Child Care*
Authors: ALBANESE PATRIZIA
Published: January 2009

Dans cet article, l'auteure présente quelques résultats d'une enquête d'approche qualitative auprès de méres et d'éducatrices visant à analyser les répercussions du programme éducatif québécois (service de garde offrant des places pour une contribution parentale de 7 par jour) sur une ville frontière defavorisée. L'étude, qui présente un échantillon des commentaires de mères et d'éducatrices, constitue la première phase d'un projet de trois volets. l'article démontre comment un investissement dans les enfants au moyen d'un programme uni‐versel a pu avoir un impact d'ensemble sur cette collectivitééconomique‐ment défavorisée, un effet remarqué dans les families et dans la collectivité et, en retour, sur les enfants eux‐mêmes.

This paper assesses the impact of Quebec's 7/day child care program on an economically disadvantaged community near the Quebec/Ontario border, using qualitative interviews with mothers of children in the program and with child care workers. A pilot snowball sample of mothers and child care workers marks the first phase of a three‐phase project in the community. This paper shows how investing in children through a universal child care initiative resonates through this economically hard‐hit community, in essence producing a ripple effect through families and the community, and reciprocally back again to children.
Behind the Screen: The Role of State‐TV Relationships in Russia, 1990–2000*
Authors: ROZANOVA JULIA
Published: January 2009

Les systèmes de régulation de la production des programmes télévisuels sont aussi importants dans les études des médias que l'analyse du corps d'un texte. l'économie politique rend possible l'étude des programmes télévisuels et des systèmes de régulation de la production télévisuelle dans un seul modèle de même que leurs interconnections. Deux systèmes régulateurs de télévision sont décrits, et les dynamiques de leur transformation sont présentées. Les résultats des entrevues avec les fonctionnaires de l'industrie télévisuelle sont utilisés pour examiner l'influence des relations entre l'État et les entreprises de télévision sur le contenu des programmes produits par la télévision russe entre 1990 et 2000.

This paper argues that the content of television programs is influenced by how their production is organized and regulated. The political‐economic approach provides a useful framework to link television programs and the regulation of TV production within a single model, and to investigate their interrelationship. Two systems of TV regulation are described in this paper and their evolution is discussed. Data from in‐depth qualitative interviews with Russian television industry insiders are used to examine the impact of changes in the regulation of television on the types and content of programs produced between 1990 and 2000.
How Distinctive Are Canadian Research Methods?*
Authors: PLATT JENNIFER
Published: January 2009

l'auteure de cet article aborde la question de la spécificité des méthodologies de recherche canadiennes, en examinant d'abord les grands modeles de méthodologies utilisés dans les articles empiriques publiés dans les principales revues canadiennes à partir des années 1960, comment ils ont changé au cours des temps et comment ils ont différé chez les anglophones et les francophones du Canada. Elle examine aussi la question de l'influence américaine soulevée par le débat qui s'est tenu sur la canadianisation. Il en ressort qu'au cours des dernières années les différences dues à la spécificité des sexes qui traversent ces divisions nationales ont été les plus importantes. l'effet final est que le modèle canadien global a quelque chose en commun avec ceux enregistrés dans les autres pays, quoique, à un niveau plus circonstancié, il soit spécifiquement canadien ou québécois. Les raisons des similarités et des différences sont analysées.

This paper addresses the question of the distinctiveness of Canadian research methods by looking first at the broad pattern of methods used in empirical articles published in leading Canadian journals from the 1960s, how these have changed over time, and how they have differed between Francophone and Anglophone Canada. Issues of U.S. influence raised by the earlier Canadianization debate are also addressed. It is found that, for the more recent period, gender differences that cut across these “national” divisions have been the more salient. The net effect is that the total Canadian pattern has something in common with that recorded for other countries, although at a more detailed level there are specifically Canadian or Québécois effects. Reasons for the similarities and differences are discussed.
Interaction between Lactic Acid Bacteria and
Mycobacterium bovis
in Ethiopian Fermented Milk: Insight into the Fate of
M. bovis
Authors: Mariam Solomon H.
Published: January 2009

Mycobacterium bovis
causes tuberculosis in animals and humans. Infected cows can transmit the bacillus to humans via milk. Milk also contains lactic acid bacteria (LAB). LAB isolated from milk were put in milk cultures together with spiked
M. bovis
. Different LAB had different abilities to reduce
M. bovis
counts, as
M. bovis
was undetectable in some while it persisted in two of the cultures.
The
Salmonella
Pathogenicity Island 2-Encoded Type III Secretion System Is Essential for the Survival of
Salmonella enterica
Serovar Typhimurium in Free-Living Amoebae
Authors: Bleasdale Benjamin , Lott Penelope J. , Jagannathan Aparna , Stevens Mark P. , Birtles Richard J. , Wigley Paul
Published: January 2009

Free-living amoebae represent a potential reservoir and predator of
Salmonella enterica
. Through the use of type III secretion system (T3SS) mutants and analysis of transcription of selected T3SS genes, we demonstrated that the
Salmonella
pathogenicity island 2 is highly induced during
S. enterica
serovar Typhimurium infection of
Acanthamoeba polyphaga
and is essential for survival within amoebae.
90-Kilodalton Heat Shock Protein, Hsp90, as a Target for Genotyping
Cryptosporidium
spp. Known To Infect Humans
Authors: Feng Yaoyu , Dearen Theresa , Cama Vitaliano , Xiao Lihua
Published: January 2009

Small-subunit (SSU) rRNA-based methods have been commonly used in the differentiation of
Cryptosporidium
species or genotypes. In order to develop a new tool for confirming the genotypes of
Cryptosporidium
species, parts of the 90-kDa heat shock protein (Hsp90) genes of seven
Cryptosporidium
species and genotypes known to infect humans (
C. hominis
,
C. parvum
,
C. meleagridis
,
C. canis
,
C. muris
,
C. suis
, and the cervine genotype), together with one from cattle (
C. andersoni
), were sequenced and analyzed. With the exception of
C. felis
from cats and
C. baileyi
from birds, the Hsp90 genes of all tested
Cryptosporidium
species were amplified. Phylogenetic analysis of the
hsp90
sequences from all these species is congruent with previous studies in which the SSU rRNA, 70-kDa heat shock protein, oocyst wall protein, and actin genes were analyzed and showed that gastric and intestinal parasites segregate into two distinct clades. In this study, the secondary products of
hsp90
produced after PCR-restriction fragment length digestion with StyI and HphI or with BbsI showed that parasites within the intestinal or gastric clade could be differentiated from each other. These data confirm the utility of the Hsp90 gene as a sensitive, specific, and robust molecular tool for differentiating species and/or genotypes of
Cryptosporidium
in clinical specimens.
Polymorphic Mucin Antigens CpMuc4 and CpMuc5 Are Integral toCryptosporidium parvumInfection In Vitro
Authors: O'Connor Roberta M. , Burns Patrick B. , Ha-Ngoc Tin , Scarpato Kristen , Khan Wasif , Kang Gagandeep , Ward Honorine
Published: January 2009

Cryptosporidium, a waterborne enteric parasite, is a frequent cause of diarrheal disease outbreaks worldwide. Thus far, the few antigens shown to be important for attachment to and invasion of the host cell byCryptosporidiumare all mucin-like glycoproteins. In order to investigate other antigens that could be important forCryptosporidiumhost-parasite interactions, theCryptosporidiumgenome databases were mined for other mucin-like genes. A single locus of seven small mucin sequences was identified on chromosome 2 (CpMuc1 to -7). Reverse transcriptase PCR analysis demonstrated that all seven CpMucs were expressed throughout intracellular development. CpMuc4 and CpMuc5 were selected for further investigation because of the significant sequence divergence betweenCryptosporidium parvumandC. hominisalleles. Rabbit anti-CpMuc5 and -CpMuc4 antibodies identified several polypeptides inC. parvumlysates, suggestive of proteolytic processing of the mucins. All polypeptides were larger than the predicted molecular weight, which is suggestive of posttranslational processing, most likely O-glycosylation. In immunofluorescence assays, both anti-CpMuc4 and -CpMuc5 antibodies reacted with the apical region of sporozoites and revealed surface-exposed epitopes. The antigens were not shed during excystation but did partition into the aqueous phase of Triton X-114 extractions. Consistent with a role in attachment and invasion, CpMuc4 and CpMuc5 could be detected binding to fixed Caco-2A cells, and anti-CpMuc4 peptide antibodies inhibitedCryptosporidiuminfection in vitro. Sequencing of CpMuc4 and CpMuc5 fromC. hominisclinical isolates identified several polymorphic alleles. The data suggest that these antigens are integral forCryptosporidiuminfection in vitro and may be potential vaccine candidates.
Gamma Interferon and Interleukin-1 Receptor 1 Regulate Neutrophil Recruitment to the Corneal Stroma in a Murine Model ofOnchocerca volvulusKeratitis
Authors: Gentil Katrin , Pearlman Eric
Published: January 2009

Toll-like receptor 2 (TLR2) is an essential mediator of corneal inflammation induced by the filarial nematodeOnchocerca volvulus, which harbors endosymbioticWolbachiabacteria. TLR2 is also required for dendritic cell activation, gamma interferon (IFN-γ) production, and neutrophil recruitment to the cornea. To examine the role of IFN-γ inO. volvuluskeratitis, C57BL/6 and IFN-γ−/−mice were immunized subcutaneously, and a soluble antigen extract fromO. volvulusadult worms (OvAg) was injected into the corneal stroma of each animal. We found that, in the absence of IFN-γ, neutrophil recruitment to the cornea was significantly impaired, whereas there was no effect on eosinophil infiltration. Since the cornea contains resident macrophages and fibroblasts and our previous studies showed that CXC chemokines mediate neutrophil recruitment, we examined the role of recombinant IFN-γ (rIFN-γ) on each cell type. We found no effect of rIFN-γ on CXC chemokine production by macrophages or corneal fibroblasts, either alone or with filarial extracts; in contrast, rIFN-γ was found to enhance OvAg-induced tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), IL-1α, and IL-1β in macrophages. Furthermore, we found that rTNF-α, rIL-1α, or rIL-1β induced CXC chemokine production by corneal fibroblasts but not by macrophages. To determine the relative contributions of endogenous cytokines, we injected OvAg into the corneal stroma of C57BL/6, IL-1 receptor 1−/−(IL-1R1−/−), and TNF-αR1/2−/−mice and examined neutrophil recruitment. We found that neutrophil infiltration was impaired in IL-1R1−/−mice but not in TNF-αR1/2−/−mice. IFN-γ therefore appears to regulate neutrophil recruitment to the corneal stroma by enhancing TLR2 expression and OvAg-induced IL-1α and IL-1β production by macrophages in the cornea, which then induce IL-1R1-dependent production of CXC chemokine by resident corneal fibroblasts.
Identification of Novel Glycosyltransferases Required for Assembly of the
Pasteurella multocida
A:1 Lipopolysaccharide and Their Involvement in Virulence
Authors: Boyce John D. , Harper Marina , St. Michael Frank , John Marietta , Aubry Annie , Parnas Henrietta , Logan Susan M. , Wilkie Ian W. , Ford Mark , Cox Andrew D. , Adler Ben
Published: January 2009

We previously determined the structure of the
Pasteurella multocida
Heddleston type 1 lipopolysaccharide (LPS) molecule and characterized some of the transferases essential for LPS biosynthesis. We also showed that
P. multocida
strains expressing truncated LPS display reduced virulence. Here, we have identified all of the remaining glycosyltransferases required for synthesis of the oligosaccharide extension of the
P. multocida
Heddleston type 1 LPS, including a novel α-1,6 glucosyltransferase, a β-1,4 glucosyltransferase, a putative bifunctional galactosyltransferase, and two heptosyltransferases. In addition, we identified a novel oligosaccharide extension expressed only in a heptosyltransferase (
hptE
) mutant background. All of the analyzed mutants expressing LPS with a truncated main oligosaccharide extension displayed reduced virulence, but those expressing LPS with an intact heptose side chain were able to persist for long periods in muscle tissue. The
hptC
mutant, which expressed LPS with the shortest oligosaccharide extension and no heptose side chain, was unable to persist on the muscle or cause any disease. Furthermore, all of the mutants displayed increased sensitivity to the chicken antimicrobial peptide fowlicidin 1, with mutants expressing highly truncated LPS being the most sensitive.
Intralesional Regulatory T-Cell Suppressive Function during Human Acute and Chronic Cutaneous Leishmaniasis Due to
Leishmania guyanensis
Authors: Bourreau E. , Ronet C. , Darcissac E. , Lise M. C. , Sainte Marie D. , Clity E. , Tacchini-Cottier F. , Couppie P. , Launois P.
Published: January 2009

The levels of regulatory T cells (Treg cells), analyzed by Foxp3 mRNA expression, were determined in lesions from patients with acute cutaneous leishmaniasis (ACL) and chronic cutaneous leishmaniasis (CCL). We demonstrated that Treg cells preferentially accumulate in lesions from ACL patients during the early phase of infection (lesion duration of less than 1 month). In addition, levels of Foxp3 mRNA transcripts were significantly higher in specimens from patients with CCL than in those from patients with ACL, suggesting a critical role of intralesional Treg cells in CCL. Intralesional Treg cells from both ACL and CCL patients were shown to have suppressive functions in vitro, since they inhibited the gamma interferon (IFN-γ) produced by CD4
+
CD25
−
T cells purified from peripheral blood mononuclear cells from the same patient in response to
Leishmania guyanensis
stimulation. Intralesional 2,3-indoleamine dioxygenase (IDO) mRNA expression was associated with that of Foxp3, suggesting a role for IDO in the suppressive activity of intralesional Treg cells. In addition, a role, albeit minor, of interleukin-10 (IL-10) was also demonstrated, since neutralization of IL-10 produced by intralesional T cells increased IFN-γ production by effector cells in an in vitro suppressive assay. These results confirm the role of intralesional Treg cells in the immunopathogenesis of human
Leishmania
infection, particularly in CCL patients.
Overexpression of MazF
Sa
in
Staphylococcus aureus
Induces Bacteriostasis by Selectively Targeting mRNAs for Cleavage
Authors: Fu Zhibiao , Tamber Sandeep , Memmi Guido , Donegan Niles P. , Cheung Ambrose L.
Published: January 2009

The role of chromosomally encoded toxin-antitoxin (TA) loci in bacterial physiology has been under debate, with the toxin proposed as either an inducer of bacteriostasis or a mediator of programmed cell death (PCD). We report here that ectopic expression of MazF
Sa
, a toxin of the TA module from
Staphylococcus aureus
, led to a rapid decrease in CFU counts but most cells remained viable as determined by differential Syto 9 and propidium iodide staining after MazF
Sa
induction. This finding suggested that the toxin MazF
Sa
induced cell stasis rather than cell death. We also showed that MazF
Sa
selectively cleaves cellular mRNAs in vivo, avoiding “important” transcripts such as
recA
,
gyrB
, and
sarA
mRNAs in MazF
Sa
-induced cells, while these three mRNAs can be cleaved in vitro. The results of Northwestern blotting showed that both
sarA
and
recA
mRNAs bind strongly to a putative RNA-binding protein. These data suggest that
S. aureus
likely undergoes stasis by protecting selective mRNA with RNA-binding proteins upon the expression of MazF
Sa
in vivo.
Maturation of the Translation Inhibitor Microcin C
Authors: Metlitskaya Anastasia , Kazakov Teymur , Vondenhoff Gaston H. , Novikova Maria , Shashkov Alexander , Zatsepin Timofei , Semenova Ekaterina , Zaitseva Natalia , Ramensky Vasily , Van Aerschot Arthur , Severinov Konstantin
Published: January 2009

Microcin C (McC), an inhibitor of the growth of enteric bacteria, consists of a heptapeptide with a modified AMP residue attached to the backbone of the C-terminal aspartate through an
N
-acyl phosphamidate bond. Here we identify maturation intermediates produced by cells lacking individual
mcc
McC biosynthesis genes. We show that the products of the
mccD
and
mccE
genes are required for attachment of a 3-aminopropyl group to the phosphate of McC and that this group increases the potency of inhibition of the McC target, aspartyl-tRNA synthetase.
Smoker-free workplace policies: developing a model of public health consequences of workplace policies barring employment to smokers: Figure 1
Authors: Houle B , Siegel M
Published: January 2009

A marked shift in tobacco-related workplace health promotion intervention involves the adoption of policies barring employment to smokers. We discuss the potential public health consequences of these policies on those affected—smokers, their families, the surrounding community and society at large. We find a lack of published evidence evaluating the effectiveness and consequences of these policies. By developing a model of policy effects, we outline possible unintended consequences. With such large gaps in the evidence base and the potential for deleterious consequences, we argue for increased discussion about the use of smoker-free employment policies as a public health intervention and for increased engagement of employers by the public health community in worksite health promotion.
Physical and ecological response to disturbance by gravel mining in a large alluvial river
Authors: Rempel Laura L. , Church Michael
Published: January 2009

The role of sediment transport during high flows for restoring fish habitat was demonstrated following an experimental gravel removal from Fraser River, British Columbia, Canada. Dry bar scalping 69 000 m3 of river sediment left a topographically simple removal area with a loose surface of gravel and sand. Two subsequent, below-average floods yielded no gravel replenishment but restored substrate grain size and some topographical complexity at the habitat scale. A third, above-average flood replenished 31% of the removal volume. High-elevation bar area, which provides fish habitat at high flows, remained 25% smaller after the three floods. Effects of mining on the fish community could not be confirmed. Benthic invertebrates recolonized the removal site immediately after mining, and differences in community composition compared with three reference sites disappeared during the first flood. Results suggest that physical changes due to this mining operation fell within the range to which local aquatic populations are accustomed during flooding, because the ecological response was modest and short-lived. Despite an extensive sampling program, inherent variability in the biological data reduced statistical power to detect an effect. Monitoring programs to support adaptive management of river fisheries will require substantial investment and planning to yield definitive results.
Genetic variability in reaction norms between farmed and wild backcrosses of Atlantic salmon (Salmo salar)
Authors: Darwish Tamara L. , Hutchings Jeffrey A.
Published: January 2009

Adaptive responses to environmental heterogeneity may vary among populations. Genetic variability in reaction norms might account for population differences in the ability to respond to environmental change and may reflect local adaptation. Reaction norms for early life history traits were compared among three population crosses of Atlantic salmon ( Salmo salar ). Two comprised second-generation backcrosses introgressed with either farmed or wild genes; the third comprised individuals from a second-generation, pure wild cross. Using a common-garden experimental protocol, each cross was exposed to three temperature regimes. Plasticity in embryonic development, growth, survival, and body size was measured from fertilization up to 24 weeks of exogenous feeding. Reaction norms differed markedly among crosses, irrespective of whether individuals interbred with those whose genes originated from another wild population or from a cultured population. We find that introgression involving individuals with comparatively few genetic differences can change reaction norms. If plasticity represents an adaptive response to local environments, then changes to reaction norms resulting from interbreeding between populations are unlikely to have a beneficial effect on fitness.
Spatial and temporal impact of pingers on porpoises
Authors: Carlström Julia , Berggren Per , Tregenza Nick J.C.
Published: January 2009

Bycatches are considered the most serious threat to harbour porpoises ( Phocoena phocoena ) and other small cetaceans worldwide. Pingers are used to reduce bycatch levels, but may also deter porpoises from critical habitats. We investigated the spatial and temporal responses of porpoises to simulated bottom-set nets equipped with periodically operating Dukane NetMark 1000 pingers. Echolocation rates were monitored by porpoise click train detectors (PODs) placed at and around the nets, and a shore-based observation team recorded surfacing positions and movements. Pinger sound significantly reduced the median echolocation encounter rate by 50%–100% at PODs placed up to 500 m and reduced the sighting rate up to 375 m from the simulated net. The average distance of approach increased by 300 m. When pingers were silent after being active for 24 h 50 min, the return time of porpoises was 6 h, in comparison with 2.5 h after pingers had been silent. During the study period of approximately 50 days, habituation was detectable at two of nine PODs. The results indicate that pingers affect porpoises at greater distances than previously observed. This confirms that pingers are an effective bycatch mitigation measure, but alternative solutions should be applied in ecologically important habitats and migration routes. An example is given from the Baltic region.
A comparison of the heat shock response in juvenile and adult rainbow trout (Oncorhynchus mykiss) — implications for increased thermal sensitivity with age
Authors: Fowler Stephanie L. , Hamilton Diana , Currie Suzanne
Published: January 2009

We conclude that the heat shock response is enhanced in juvenile compared with adult rainbow trout, Oncorhynchus mykiss . We have shown that the magnitude of the inducible heat shock response, as measured by increases in the heat shock protein (Hsp) Hsp70 is significantly greater in the hearts of fingerling than in adult trout following an acute (1 h) heat stress at 25 °C. Juvenile fish also express higher levels of constitutive Hsps (Hsc70, Hsp90) in their tissues, possibly reflecting higher rates of protein synthesis and increased chaperone function in this early life stage. This robust heat shock response in juvenile trout may contribute to a greater thermal resistance that is often observed in young salmonid fish.
Genetic isolation by distance and localized fjord population structure in Pacific cod (Gadus macrocephalus): limited effective dispersal in the northeastern Pacific Ocean
Authors: Cunningham Kathryn Maja , Canino Michael Francis , Spies Ingrid Brigette , Hauser Lorenz
Published: January 2009

Genetic population structure of Pacific cod, Gadus macrocephalus , was examined across much of its northeastern Pacific range by screening variation at 11 microsatellite DNA loci. Estimates of FST(0.005 ± 0.002) and RST(0.010 ± 0.003) over all samples suggested that effective dispersal is limited among populations. Genetic divergence was highly correlated with geographic distance in an isolation-by-distance (IBD) pattern along the entire coastal continuum in the northeastern Pacific Ocean (~4000 km; r2= 0.83), extending from Washington State to the Aleutian Islands, and over smaller geographic distances for three locations in Alaska (~1700 km; r2= 0.56). Slopes of IBD regressions suggested average dispersal distance between birth and reproduction of less than 30 km. Exceptions to this pattern were found in samples taken from fjord environments in the Georgia Basin (the Strait of Georgia (Canada) and Puget Sound (USA)), where populations were differentiated from coastal cod. Our results showed population structure at spatial scales relevant to fisheries management, both caused by limited dispersal along the coast and by sharp barriers to migration isolating smaller stocks in coastal fjord environments.