Laboratory diagnosis of Schistosomiasis in areas of low transmission: a review of a line of research

After 57 years of successful control of schistosomiasis in Venezuela, the prevalence and intensity of infection have declined. Approximately 80% of the individuals eliminate less than 100 eggs/g of stools, therefore morbidity is mild and the majority are asymptomatic. The sensitivity of Kato-Katz decreases to approximately 60%. Available serological methods for the detection of circulating antigens only reach a 70% of sensitivity. Tests based on the detection of antibodies by immunoenzymatic assays have been improved. The circumoval precipitine test has shown a high sensitivity (97%), specificity (100%), and correlation with oviposition, being considered the best confirmatory diagnostic test. Additionally to the classical immunoenzymatic assays, the development of the alkaline phosphatase immunoassay, allowed to reach a 100% specificity with an 89% sensitivity. Recently, we have developed a modified ELISA in which the soluble egg antigen is treated with sodium metaperiodate (SMP-ELISA) in order to eliminate the glycosilated epitopes responsible for the false positive reactions. The specificity and sensitivity reaches 97% and 99%, respectively. Synthetic peptides from the excretory-secretory enzymes, cathepsin B (Sm31) legumain (Sm32) and cathepsin D (Sm45), have been synthesized. The combination of two peptides derived from the Sm31 have been evaluated, reaching a sensitivity of 96% when analyzed independently and with a 100% specificity. Antibodies raised in rabbits against peptides derived from the Sm31 and Sm32 are currently evaluated in two different antigen-capture-based assays. The development of a simple, cheap and reliable test that correlates with parasite activity is a major goal.

Differential requirement for CD4 help in the development of an antigen-specific CD8+ T cell response depending on the route of immunization.

Previous studies in our laboratory have shown that DBA/2 mice injected i.p. with syngeneic P815 tumor cells transfected with the HLA-CW3 gene (P815-CW3) showed a dramatic expansion of activated CD8+CD62L- T cells expressing exclusively the Vbeta10 segment. We have used this model to study the regulatory mechanisms involved in the development of the CW3-specific CD8+ response, with respect to different routes of immunization. Whereas both intradermal (i.d.) and i.p. immunization of DBA/2 mice with P815-CW3 cells led to a strong expansion of CD8+CD62L-Vbeta10+ cells, only the i.d. route allowed this expansion after immunization with P815 cells transfected with a minigene coding for the antigenic epitope CW3 170-179 (P815 miniCW3). Furthermore, depletion of CD4+ T cells in vivo completely abolished the specific response of CD8+CD62L-Vbeta10+ cells and prevented the rejection of P815-CW3 tumor cells injected i.p., whereas it did not affect CD8S+CD62L-Vbeta10+ cell expansion after i.d. immunization with either P815-CW3 or P815 miniCW3. Finally, the CW3-specific CD8+ memory response was identical whether or not CD4+ T cells were depleted during the primary response. Collectively, these results suggest that the CD8+ T cell response to P815-CW3 tumor cells injected i.p. is strictly dependent upon recognition of a helper epitope by CD4+ T cells, whereas no such requirement is observed for i.d. injection.

Comparative studies on the biology and filarial susceptibility of selected blood-feeding and autogenous Aedes togoi sub-colonies

Blood-feeding and autogenous sub-colonies were selected from a laboratory, stock colony of Aedes togoi, which was originally collected from Koh Nom Sao, Chanthaburi province, Southeast Thailand. Comparative biology and filarial susceptibility between the two sub-colonies (blood-feeding: F11, F13; autogeny: F38, F40) were investigated to evaluate their viability and vectorial capacity. The results of comparison on biology revealed intraspecific differences, i.e., the average egg deposition/gravid female (F11/F38; F13/F40), embryonation rate (F13/F40), hatchability rate (F11/F38; F13/F40), egg width (F11/F38), wing length of females (F13/F40), and wing length and width of males (F11/F38) in the blood-feeding sub-colony were significantly greater than that in the autogenous sub-colony; and egg length (F11/F38) and width (F13/F40), and mean longevity of adult females (F11/F38) and males (F13/F40) in the blood-feeding sub-colony were significantly less than that in the autogenous sub-colony. The results of comparison on filarial susceptibility demonstrated that both sub-colonies yielded similar susceptibilities to Brugia malayi [blood-feeding/autogeny = 56.7% (F11)/53.3%(F38), 60%(F13)/83.3%(F40)] and Dirofilaria immitis [blood-feeding/autogeny = 85.7%(F11)/75%(F38), 45%(F13)/29.4%(F40)], suggesting autogenous Ae. togoi sub-colony was an efficient laboratory vector in study of filariasis.

Molluscicidal action of the latex of Euphorbia splendens var. hislopii N.E.B. ("Christ's Crown") (Euphorbiaceae) against Lymnaea columella (Say, 1817) (Pulmonata: Lymnaeidae), intermediate host of Fasciola hepatica Linnaeus, 1758 (Trematode: Fasciolidae): 1- test in laboratory

The latex action of Euphorbia splendens var. hislopii (Christ's Crown) against snails Lymnaea columella, intermediate host of Fasciola hepatica, derived from irrigation ditches of the Station of Pisciculture at Universidade Federal Rural do Rio de Janeiro, was studied in the laboratory. Lab bioassays, using aqueous solutions of the latex, varying between 0.1 and 10 mg/l, have proven molluscicidal activity of the product collected on the same day the tests were performed, during the four seasons of the year, finding the following lethal concentrations (LC90): 1.51 mg/l in the spring; 0.55 mg/l in the summer; 0.74 mg/l in the fall and 0.93 mg/l in winter, after 24 h exposure of the snails, showing significant differences among the seasons of the year (ANOVA test, F = 11.01, G.L.= 3/33, p < 0.05), as well as among the concentrations (ANOVA test, F = 27.38, G.L.= 11/33, p < 0.05). In the summer, mortality reached 100% from concentration at 0.6 mg/l, the same during fall and in winter as of 1 mg/l, while in spring it only reached 100% mortality as of 2 mg/l. Mortality in the controls was low, reaching 5% in the summer and winter and 10% in the fall and spring. None of the samples died. During the assay, with an aqueous solution of the latex at a concentration of 5 mg/l, in order to check the time of duration of the product effect, in the laboratory, it was observed that the molluscicidal activity remained stable up to the 15th day after the beginning of the test with 100% mortality of L. columella, gradually losing its effect until the 23rd day, when we no longer observed animal mortality. In the control group, there was a random daily variation in mortality rate ranging 0-50% after 48 h of observation for 30 days.

Fermanagh - Your Life in Your Hands

This project intends to build on the success in equipping individuals with mental health problems, who are obese, with the skills necessary to make healthier lifestyle choices.Particpants will work as a group and support each other. A range of sessions were held on health issues of importance to clients (stress, exercise, mental health) through information workshops, training, pharmacy clinics, cooking etc. For the participants involved in the project their confidence has grown and they are able to share their learning with others at the centre. The clients are aware of other services and how to access them. The pharmacist role played a visit to the doctors to help clients get the best out of their appointment. The mental health of those involved has also imporved and has spurred them on to make changes in their overall lifestyle.

A comparative parasitologic study on Biomphalaria glabrata snail and C3H/He mice infected with human and murine isolates of Schistosoma mansoni derived from Sumidouro, Rio de Janeiro, Brazil

Experiments were carried out to analyze the biological characteristics of two sympatric isolates of Schistosoma mansoni derived from humans and murines in a low endemic transmission area (Sumidouro county, state of Rio de Janeiro, Brazil). Sympatric reared-laboratory Biomphalaria glabrata and C3H/He mice were used as experimental hosts. Parameters assessed comprised: precercarial period, infectivity and mortality (snails), prepatent period, infectivity (percentage of cercariae maturation into adult worm) and intestinal egg count (mice). The murine isolate showed a shorter precercarial period and higher infectivity than human isolate (p < 0.05). This biological heterogenicity did not correspond to the vertebrate data because any biological parameter presented significant difference (p > 0.05). These data suggest that both isolates are local sub-populations, providing support for the hypotheses that in a same biotope mixed populations or sub-populations circulate among their main host (human beings) and/or rodent as an anfixenous infection.

Feeding, defecation, and development times of Meccus longipennis Usinger, 1939 (Hemiptera: Reduviidae: Triatominae) under laboratory conditions

Aspects related to hatching, time-lapse between presenting the blood-meal and beginning of feeding, feeding time, postfeed defecation delay, mortality, and fecundity for each stage of Meccus longipennis life-cycle were evaluated. The bugs were maintained in a dark incubator at 27 ± 1ºC and 80 ± 5% rh, were fed weekly and checked daily for ecdysis or death. The hatching rate observed for 300 eggs was 76.7% and the average time of hatching was 19.8 days. Mean time-lapse between presentation of the blood meal and the beginning of feeding was under 5 min in nymphal stages and postfeed defecation delay was under 10 min in most stages, except in fourth and fifth stages. Mean feeding time was longer than 10 min in most stages, except in fourth stage. One hundred thirty-one nymphs (N) (65.5%) completed the cycle and the average time from NI to adult was 192.6 ± 34.8 days. The average span in days for each stage was 18.1 for NI, 21.4 for NII, 29.5 for NIII, 45.5 for NIV and 55.9 for NV. The number of bloodmeals at each nymphal stage varied from 1 to 5. The mortality rate was 3.29 for NI, 6.8 for NII, 2.92 for NIII 3.76 for NIV, and 10.16 for NV nymphs. The average number of eggs laid per female in a 9-month period was 615.6. Based on our results, we conclude that M. longipennis has some biological and behavioral characteristics which influence its capacity of becoming infected and transmitting Trypanosoma cruzi to human populations in those areas of Mexico where it is currently present.

Clean hands? It's OK to ask

This poster is part of an extension of the cleanyourhands campaign, aimed at preventing the spread of healthcare associated infections (HCAIs) in community healthcare settings including primary care and dental services, residential and nursing homes (including independent sector homes), hospices and independent clinics/hospitals. It is designed to heighten awareness in patient/relative waiting areas of how healthcare staff can help protect patients from avoidable infections by cleaning their hands. Due to licensing restrictions, this poster is not available for download. Limited numbers are available from local HSC Trusts (Belfast HSCT and South Eastern HSCT on 028 9056 5862; Southern HSCT on 028 3741 2887; Northern HSCT on 028 2563 5575; Western HSCT on 028 7186 5127).

Don't walk past: clean hands only take a minute

This poster is part of an extension of the cleanyourhands campaign, aimed at preventing the spread of healthcare associated infections (HCAIs) in community healthcare settings including primary care and dental services, residential and nursing homes (including independent sector homes), hospices and independent clinics/hospitals. It is designed for pump dispenser areas to heighten awareness of protecting patients from avoidable infections by cleaning of hands. Due to licensing restrictions, this poster is not available for download. Limited numbers are available from local HSC Trusts (Belfast HSCT and South Eastern HSCT on 028 9056 5862; Southern HSCT on 028 3741 2887; Northern HSCT on 028 2563 5575; Western HSCT on 028 7186 5127).

Clean your hands: hand hygiene in the community - guidance

This leaflet is part of an extension of the cleanyourhands campaign, aimed at preventing the spread of healthcare associated infections (HCAIs) in community healthcare settings including primary care and dental services, residential and nursing homes (including independent sector homes), hospices and independent clinics/hospitals. It describes the campaign and outlines the campaign resources. Due to licensing restrictions, this folder is not available for download. Limited numbers are available from local HSC Trusts (Belfast HSCT and South Eastern HSCT on 028 9056 5862; Southern HSCT on 028 3741 2887; Northern HSCT on 028 2563 5575; Western HSCT on 028 7186 5127).

Changes associated with laboratory rearing in antennal sensilla patterns of Triatoma infestans, Rhodnius prolixus, and Rhodnius pallescens (Hemiptera, Reduviidae, Triatominae)

We examined changes in the array of antennal sensilla of three species of Triatominae (Triatoma infestans, Rhodnius prolixus, and R. pallescens) following their establishment for different periods in laboratory culture. In each case, the laboratory colonies were compared with conspecific samples taken directly from the field, by quantitative analysis of the sensilla arrays on the three distal segments of the antenna in terms of the densities of three types of chemoreceptors (basiconics and thick and thin walled trichoids) and one type of mechanoreceptor (bristles). Sensilla densities were compared by ANOVA or non-parametric tests, and by multivariate discriminant analysis. Strains of the same species reared in different laboratories showed significant differences in their sensilla arrays, especially when compared to field-collected material from the same geographic origin. A Bolivian strain of T. infestans reared in the laboratory for 15 years and fed at monthly intervals, showed greatest differences from its conspecific wild forms, especially in terms of reductions in the number of chemoreceptors. By contrast, an Argentine strain of T. infestans reared for 25 years in the laboratory and fed weekly, showed a relative increase in the density of mechanoreceptors. A Colombian strain of R. prolixus reared for 20 years and fed weekly or fortnightly, showed only modest differences in the sensilla array when compared to its wild populations from the same area. However, a Colombian strain of R. pallescens reared for 12 years and fed fortnightly, did show highly significant reductions in one form of chemoreceptor compared to its conspecific wild populations. For all populations, multivariate analysis clearly discriminated between laboratory and field collected specimens, suggesting that artificial rearing can lead to modifications in the sensory array. This not only supports the idea of morphological plasticity in these species, but also suggests caution in the use of long-established laboratory material for experimental studies designed to extrapolate the natural behaviour and physiology of these species.

The effect of thrombolysis on short-term improvement depends on initial stroke severity.

A large number of parameters have been identified as predictors of early outcome in patients with acute ischemic stroke. In the present work we analyzed a wide range of demographic, metabolic, physiological, clinical, laboratory and neuroimaging parameters in a large population of consecutive patients with acute ischemic stroke with the aim of identifying independent predictors of the early clinical course. We used prospectively collected data from the Acute Stroke Registry and Analysis of Lausanne. All consecutive patients with ischemic stroke admitted to our stroke unit and/or intensive care unit between 1 January 2003 and 12 December 2008 within 24 h after last-well time were analyzed. Univariate and multivariate analyses were performed to identify significant associations with the National Institute of Health Stroke Scale (NIHSS) score at admission and 24 h later. We also sought any interactions between the identified predictors. Of the 1,730 consecutive patients with acute ischemic stroke who were included in the analysis, 260 (15.0%) were thrombolyzed (mostly intravenously) within the recommended time window. In multivariate analysis, the NIHSS score at 24 h after admission was associated with the NIHSS score at admission (β = 1, p < 0.001), initial glucose level (β = 0.05, p < 0.002) and thrombolytic intervention (β = -2.91, p < 0.001). There was a significant interaction between thrombolysis and the NIHSS score at admission (p < 0.001), indicating that the short-term effect of thrombolysis decreases with increasing initial stroke severity. Thrombolytic treatment, lower initial glucose level and lower initial stroke severity predict a favorable early clinical course. The short-term effect of thrombolysis appears mainly in minor and moderate strokes, and decreases with increasing initial stroke severity.

Directory of Food Safety Laboratory Services

All laboratories play a key role in protecting public health by analysing the microbiological and chemical content of food so that it is safe to eat. On the island of Ireland there are many laboratories & institutions involved in food safety monitoring, surveillance, analysis and research. Some operate directly or are under the aegis of government departments, local and health authorities. Others are privately owned or within third level institutes of higher education and campus companies, and other laboratory establishments are funded or run by various national agencies. These laboratories produce high quality scientific information that benefits public health through routine testing and research encompassing a broad range of foods.

Biology of the first generation of a laboratory colony of Nyssomyia intermedia (Lutz & Neiva, 1912) and Nyssomyia neivai (Pinto, 1926) (Diptera: Psychodidae)

The phlebotomine sand flies Nyssomyia intermedia (Lutz & Neiva, 1912) and Nyssomyia neivai (Pinto, 1926) are very close and may be involved in the transmission of Leishmania spp. Ross, 1903 in Brazil. The biology of the first laboratory-reared generations of these species, descended from insects captured in Além Paraíba (N. intermedia) and Corinto (N. neivai) in the Brazilian state of Minas Gerais, is described here. The captured females were fed on hamsters and maintained individually in rearing pots. Laboratory temperature and relative humidity were maintained at 25-26ºC and 80% respectively. The productivity of the first generation of N. intermedia was greater than that of N. neivai, and its development time clearly shorter, particularly for the second and third larval instars.

Life tables and reproductive parameters of Lutzomyia spinicrassa (Diptera: Psychodidae) under laboratory conditions

Lutzomyia spinicrassa is a vector of Leishmania braziliensis in Colombia. This sand fly has a broad geographical distribution in Colombia and Venezuela and it is found mainly in coffee plantations. Baseline biological growth data of L. spinicrassa were obtained under experimental laboratory conditions. The development time from egg to adult ranged from 59 to 121 days, with 12.74 weeks in average. Based on cohorts of 100 females, horizontal life table was constructed. The following predictive parameters were obtained: net rate of reproduction (8.4 females per cohort female), generation time (12.74 weeks), intrinsic rate of population increase (0.17), and finite rate of population increment (1.18). The reproductive value for each class age of the cohort females was calculated. Vertical life tables were elaborated and mortality was described for the generation obtained of the field cohort. In addition, for two successive generations, additive variance and heritability for fecundity were estimated.