Impact of the post-weaning parasitism history on an experimental Haemonchus contortus infection in Creole goat kids.

Gastrointestinal nematode (GIN) infections have an important negative impact on small ruminant production. The selection of genotypes resistant to these parasitic infections is a promising alternative control strategy. Thus, resistance against GIN is an important component of small ruminant breeding schemes, based on phenotypic measurements of resistance in immune mature infected animals. In this study we evaluated both the impact of the post-weaning parasitism history on the response to an experimental Haemonchus contortus infection of resistant and susceptible Creole kids chosen on the basis of their estimated breeding value, and the interaction with the kid's genetic status. During the post-weaning period (from 3 months until 7 months of age) Creole kids were reared at pasture according to four different levels of a mixed rotational stocking system with Creole cattle: 100% (control), 75% (GG75), 50% (GG50), and 25% (GG25) of the total stocking rate of the pasture. The level of infection of the kids decreased significantly at 50% and 25% of the total stocking rate. After the post-weaning period at pasture, at 11 months of age kids were experimentally infected with H. contortus. The faecal egg counts (FEC) were significantly lower in the groups showing the highest FEC at pasture. This result suggests that a degree of protection against an experimental H. contortus infection occurred during the post-weaning period and was dependant on the level of parasitism. Interestingly, no interaction was observed between this level of protection and the genetic status. In conclusion, the level of post-weaning natural parasitism history at pasture would not influence the genetic status evaluation. More generally our results suggest that it would be better to expose kids to a high level of gastrointestinal parasitism during the post-weaning period in order to increase the basal level of resistance thereafter.

In vitro effects of Musa x paradisiaca extracts on four developmental stages of Haemonchus contortus.

This study was carried out to evaluate the in vitro effect of Musa x paradisiaca stem and leaf against the parasitic nematode of small ruminants Haemonchus contortus. Three extracts (aqueous, methanolic and/or dichloromethane) of Musa x paradisiaca stem and leaf were tested in vitro on four developmental stages of H. contortus using egg hatch assay (EHA), larval development assay (LDA), L3 migration inhibition assay (LMI) and adult worm motility assay (AWM). The highly significant (P<0.0001) ability to stop larval development (inhibition >67% for each extract) and the negative effect of the dichloromethane extract of leaf on adult worm motility (43% of inhibition of motility after 24h of incubation) compared to the negative controls, suggest anthelmintic properties of Musa x paradisiaca stem and leaf against H. contortus. The active principles responsible for the activity could be secondary metabolites such as terpenoid and flavonoid compounds present in the leaf and stem of the plant.

Effects of single or trickle Haemonchus contortus experimental infection on digestibility and host responses of naïve Creole kids reared indoor.

The objective of this study was to compare the effects of the type of Haemonchus contortus experimental infection (trickle infection, TI versus single infection, SI) on feed intake, nutrients digestibility, parasitological and haematological measures, and plasma leptin in Creole kids. The animals were infected over 2 periods (challenge 1 and challenge 2) of 6 weeks each, corresponding respectively to the primary and the secondary infection. Periods prior infection (1 week each) were considered as controls. The primary infection was realized with 35 Creole kids (18.40±3.76 kg BW) housed in individual boxes and fed a hay-based diet. The secondary infection continued with 29 kids (21.90±3.40 kg BW) from the initial 35. A total of 6 kids and 8 kids were slaughtered for measuring nematode burden at the end of the primary and the secondary infection, respectively. Measurements of nutrients digestibility were made at 0, 3 and 5 weeks post-infection for both challenges. Faecal egg count (FEC), blood eosinophilia and packed cell volume (PCV) were monitored weekly. Feed intake (dry matter intake, DMI) and nutrients digestibility were negatively affected by H. contortus infection only during the primary infection. Plasma leptin changed significantly over time (P=0.0002) but was not affected by the infection type. Effect of infection type was observed only on crude protein digestibility during the primary infection, which was lower in the TI group (P<0.01). The overall level of blood eosinophilia was significantly higher in the TI group (P<0.0001) during both challenges. The overall FEC mean was significantly higher in the SI compared with the TI groups, during both challenges (P<0.02). These results were related to the mean female length significantly higher in the SI group compared with the TI group during challenge 1 (P=0.004), and the number of adult nematode significantly lower in the TI group compared with the SI group during the challenge 2 (P=0.05). The results showed that the response of Creole kids to H. contortus experimental infection was in part dependent on the type of experimental infection. Our data suggest that plasma leptin would not be involved in the response of Creole kids against H. contortus infection, as no relationship between its plasma level and the transient reduction in voluntary feed intake observed in both groups during the primary infection was observed.

In vitro effects of Cassava (Manihot esculenta) leaf extracts on four development stages of Haemonchus contortus.

Three extracts (aqueous, methanolic and dichloromethane) of Manihot esculenta (Cassava) leaf were tested in vitro on four development stages of Haemonchus contortus using egg hatch assay (EHA), larval development assay (LDA), L3 migration inhibition assay (LMI) and adult worm motility assay (AWM). Compared to the negative control, significant effects (P<0.0001) were observed for the methanolic extract of leaf against larval development (57.6% +/-7.6), with a dose dependent effect. These results suggest that Cassava possess anthelmintic activity against H. contortus. The active principles responsible for the activity could be the terpenoids and condensed tannin compounds present in the leaf.

In vitro effects of Tabernaemontana citrifolia extracts on Haemonchus contortus.

Tabernaemontana citrifolia (Apocynaceae) is traditionally used as an anthelmintic preparation for ruminants in Guadeloupe (French West Indies). This study was carried out to evaluate the in vitro effect of this plant against the parasitic nematode of small ruminants Haemonchus contortus. Three extracts (aqueous, methanolic and dichloromethane) of T. citrifolia fruit, leaf and root were tested on four developmental stages of the parasite, using egg hatch assay (EHA), larval development assay (LDA), L3 migration inhibition assay (LMI), and adult worm motility assay (AWM). Compared to the negative control, significant effects were observed for the different parts of T. citrifolia but with differences depending on the parasitic stage; efficacies on the larval development of H. contortus from 88.9% to 99.8% for fruit, from 72.1% to 83.8% for root and from 33.5% to 85% for leaf with dose-dependent effect for the methanolic extract. The root gave the best result on EHA (22.7% efficacy for dichloromethane extract) and AWM (56% efficacy, with dose-dependent effect for dichloromethane extract) and the leaf on LMI (49.4% efficacy). These results suggest that T. citrifolia possess anthelmintic activity against H. contortus. The active ingredients responsible for the activity could be the alkaloid compounds present in the plant parts of the plant.

An international external quality assessment for molecular diagnosis of hereditary recurrent fevers: a 3-year scheme demonstrates the need for improvement.

Hereditary recurrent fevers (HRF) are rare diseases caused by molecular defects in genes involved in the regulation of innate immunity. Sixty-seven international laboratories participated in an external quality assessment (EQA) scheme, which was developed to appraise the accuracy of genetic testing. Reports were evaluated for the 12 items recommended by the OECD (Organisation for Economic Co-Operation and Development) guidelines for molecular diagnostics. The best documented items were the name of the gene, the biologist, or the patient, whereas information on the test and screening limits, and clinical interpretation of the disease inheritance were scarcely provided. The mutation nomenclature was incomplete in about 70% of the cases. In the first 2 years of EQA, we identified almost 30% genotyping error rate, which decreased markedly in the last year. The combined performance on the basis of the correct identification of all genotypes by a given laboratory in all the 3 years was only 40%, showing a critical need for improvement.

Neutrophil activation induced by placental factors in normal and pre-eclamptic pregnancies in vitro.

Increased neutrophil activation has been demonstrated in women with pre-eclampsia. Activated neutrophils may play a significant role in the vascular endothelial pathophysiology in this disorder of pregnancy. How neutrophils become activated in pre-eclampsia is unknown. It has been proposed that activating factors could be produced and released by the placenta. To test if placental factors could stimulate neutrophil activation and what mechanism might be involved, neutrophils isolated from healthy female volunteers were exposed to the conditioned medium (CM) derived from either normal (Nor) or pre-eclamptic (PE) placental villous culture. Neutrophil-endothelial adhesion, neutrophil superoxide generation, elastase activity and integrin expression were measured. The data were analysed by ANOVA. A P value less than 0.05 was considered statistically significant. All values are expressed as a mean+/-s.e. We found: (1) neutrophil-endothelial adhesion was significantly increased in neutrophils exposed PE-CM than those exposed to Nor-CM and non-CM, P< 0.01; (2) both Nor-CM and PE-CM could stimulate neutrophils to generate more superoxide radicals; (3) there was no difference in elastase activity after neutrophil exposure to Nor-CM compared to PE-CM, P> 0.1; (4) significant changes in CD62L and CD11b expression were found in neutrophils exposed to PE-CM. We conclude that factors produced by the placenta can activate neutrophils by an increase in superoxide generation and modulation of adhesion molecule expression. Upregulation of surface adhesion molecule CD11 expression may be responsible for the increased neutrophil-endothelial adhesion induced by factors derived from pre-eclamptic placentae.

[Labor in the squatting position. [A randomized trial comparing the squatting position with the classical position for the expulsion phase]. / L'accouchement en position accroupie. Essai randomisé comparant la position accroupie à la position classique en phase d'expulsion.

OBJECTIVE OF STUDY: To evaluate the influence of a vertical delivery position squatting during expulsion, studying different parameters such as duration of expulsion, neonatal status, delivery mode, frequency of hemorrhagia, perineum status and patient comfort. TYPE OF STUDY: Randomized, unicentric, comparative, open, prospective. MATERIAL AND METHOD: After a retrospective study determining feasibility, 240 patients were randomized to equal 2 groups in which the delivery was performed in squat position versus in lithotomy position. All the above described parameters were recorded and treated by the Epi-Info software package using Student t test, chi 2 and Kruskall-Wallis test. RESULTS: Our study has shown a tendency to shorten the length of the expulsion phase and a reduced use of forceps in the squat position. This is consistent with other studies published in the literature. We would like to emphasize that even if it does not show a medical advantage on the studied parameters, the squat position is not deleterious and can provide a better comfort for the patients who want to use it.

Medical conditions and the risk of motor vehicle crashes in men.

OBJECTIVE: To determine whether men aged 45 to 70 years with any medical condition are at an increased risk of involvement as drivers in police-reported motor vehicle crashes. DESIGN: Case-control study. SETTING: Province-wide population-based sampling. PARTICIPANTS: A total of 2504 drivers randomly selected from those involved as a driver in a motor vehicle crash (cases) and 2520 men not involved in a crash (controls) during a 6-month period. DATA COLLECTION: The Societé de l'assurance automobile du Quebec (SAAQ) computerized files provided data on crashes, age, and medical conditions. A mailed questionnaire elicited information on usual mileage and driving conditions. RESULTS: Data from the SAAQ files were obtained for all 5024 drivers. The overall response rate to the mailed survey was 35.5% with no statistically significant differences in the distribution of characteristics between respondents and nonrespondents. There was no increase in crude (odds ratio, 0.99; 95% confidence interval, 0.85-1.17) or age-adjusted risk of crashes for men with a medical condition in the entire sample of subjects (N = 5024). Among respondents to the mailed questionnaire only, men with a medical condition showed no increased crude risk of crashes (odds ratio, 0.99; 95% confidence interval, 0.76-1.27); no difference was observed after adjustment for age, mileage driven, driver behaviors, and sociodemographic characteristics (odds ratio, 0.91; 95% confidence interval, 0.64-1.31). CONCLUSIONS: Unlike previous studies, the risk estimate was derived from a population-based sample of drivers and adjusted for age, mileage driven, driver behaviors, and sociodemographic characteristics in multivariate analyses. The adjusted estimates failed to show an increased risk of motor vehicle crashes for drivers with a medical condition.

Are drivers with CVD more at risk for motor vehicle crashes? Study of men aged 45 to 70.

OBJECTIVE: To examine whether male drivers aged 45 to 70 years suffering from cardiovascular disease (CVD) are more likely to be involved in motor vehicle crashes (MVC) that are reported to the police. DESIGN: Population-based case-control study. SETTING: Data on drivers' ages and medical conditions were compiled from the Societé de l'assurance automobile du Québec's (SAAQ) computerized files. A questionnaire was mailed to all subjects to collect additional information on annual distances driven and various driving behaviours. PARTICIPANTS: Age-stratified population-based random sample. Subjects were 2504 drivers involved in MVCs during a 6-month period; controls were 2520 drivers not involved in crashes. MAIN OUTCOME MEASURES: Proportion of drivers with CVD involved in MVCs. RESULTS: Response rate to the questionnaire was 35.5%. Analysis of the SAAQ files' entire sample of 5024 drivers showed that drivers suffering from CVD were less likely to be involved in MVCs (odds ratio [OR] 0.82, 95% confidence interval [CI] 0.67 to 0.99) than drivers without CVD. Although the estimate of risk remains unchanged when adjusted for age, it becomes statistically insignificant. It also remains unchanged and statistically insignificant when adjusted for yearly distance driven and driver behaviour, as shown by responses to the questionnaire. Drivers suffering from CVD drove significantly less each year (8900 km) than drivers without medical conditions (13,000 km). CONCLUSION: This study shows no increased risk of motor vehicle crashes for drivers suffering from CVD.

Attitudes towards co-workers affected by occupational hearing loss. I: Questionnaire development and inquiry.

Previous studies have shown that attitudes of workers towards their hearing impaired colleagues strongly contribute to the psychosocial disadvantages associated with occupational hearing loss (OHL). A questionnaire has been designed to characterize such attitudes. In phase I, a preliminary version consisting of 45 items was divided equally into scales of knowledge, attitudes and reported behaviour towards co-workers affected by OHL. Answers from 176 workers from a metal products plant enabled us to identify discriminative items that belonged to an appropriate factorial structure. In phase II, the response of 125 miners to a second version of the questionnaire, comprising 32 items, permitted further refinement. The final version was tested with 250 workers from three plants. Answers on the scale measuring knowledge showed that noise-exposed workers were not aware of the major consequences of OHL. Attitudes towards hearing impaired co-workers were generally favourable, but this finding appeared to reflect a strong social desirability bias. Reported behaviour indicated that a majority of workers are not inclined to adopt types of conduct that favour communication with people having OHL. Those workers who perceive themselves to be moderately to severely hearing impaired had a more negative image of hearing impaired workers, while reporting more facilitating and helping types of behaviour towards them, they also reported much more frequent contact with them. The findings provide strong indications that hearing impairment in noisy industrial settings frequently goes unnoticed and that many workers who are at risk of developing OHL are often unaware that some of their co-workers are already affected. These findings offer useful leads for the development of an awareness programme on the consequences of OHL.

Elderly patients' use of hospital-based emergency services.

Past studies have shown in many instances that elderly people are represented in the hospital emergency room in proportion to their distribution in the population. It is possible, though, that elderly patients in the emergency room are using different types of resources than individuals of a younger age. Samples of two hospital emergency room users were selected in 1981 and in 1986. Patients aged 25 years or older were included in the study. The dependent variable was the extent to which patients used resources available at the hospital emergency room only or at alternative emergency medical services in the community. The effect of age on the use of resources in the hospital emergency rooms was estimated separately for those who were transported to the emergency room by ambulance and for those who were not. Age had an effect on use of resources under both conditions, regardless of the patients' gender, time of the visits, availability of alternative sources of emergency care, and diagnostic categories. The role of the hospital emergency room is to address medical care needs of specific segments of the population in special circumstances. Elderly emergency room patients are indeed one of these specific segments with very special needs.

Socio-spatial perspectives on the utilization of emergency hospital services in two urban territories in Quebec.

Hospital emergency services located in urban areas have been severely congested for several years in the province of Quebec. This problem is not caused by ambulatory patients who are using emergency services as a regular source of care, but by patients in need of emergency services. To study the factors affecting the utilization rates of emergency services in two urban areas, the city of Laval and the Quebec metropolitan area, two samples of more than 30,000 patients each were drawn from the 1981 file of the Régie de l'assurance-maladie du Quebec. The utilization rates of emergency services for emergent and urgent causes in these two samples were computed on the basis of the census tract location of these patients. The socio-economic characteristics of these census tracts were taken from the 1981 Canadian census, the distance travelled from each census tract to the location of hospital emergency services was computed and included as a predictor of the utilization rates. Also, the prevalence of chronic and psychiatric diagnoses were obtained for each census tract. The result of the analysis showed that distance affected the utilization rates only in the Quebec metropolitan area where the hospitals are mostly located in the downtown area near deprived and working class neighbourhoods, while the socio-economic characteristics affected the utilization rates in both Quebec and Laval.