21 research outputs found
Isothermal Recombinase Polymerase amplification (RPA) of Schistosoma haematobium DNA and oligochromatographic lateral flow detection
© 2015 Rosser et al. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. The attached file is the published version of the article
The substructure of three repetitive DNA regions of Schistosoma haematobium group species as a potential marker for species recognition and interbreeding detection
The file attached is the Published/publisher’s pdf version of the article.© The Author(s). 2017 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated
A salting out and resin procedure for extracting Schistosoma mansoni DNA from human urine samples
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Previous issue date: 2010Fundação Oswaldo Cruz. Laboratório de Esquistossomose. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Laboratório de Imunologia Celular e Molecular. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Laboratório de Imunologia Celular e Molecular. Belo Horizonte, MG, Brasil/ Universidade Federal de Ouro Preto. Escola de Farmácia. Laboratório de Pesquisas ClÃnicas. Ouro Preto, MG, BraziBackground: In this paper a simple and cheap salting out and resin (InstaGene matrix® resin - BioRad) DNA extraction method from urine for PCR assays is introduced. The DNA of the fluke Schistosoma mansoni was chosen as the target since schistosomiasis lacks a suitable diagnostic tool which is sensitive enough to detect low worm burden. It is well known that the PCR technique provides high sensitivity and specificity in detecting parasite DNA. Therefore it is of paramount importance to take advantage of its excellent performance by providing a simple to handle and reliable DNA extraction procedure, which permits the diagnosis of the disease in easily obtainable urine samples.
Findings: The description of the extraction procedure is given. This extraction procedure was tested for reproducibility and efficiency in artificially contaminated human urine samples. The reproducibility reached 100%, showing positive results in 5 assay repetitions of 5 tested samples each containing 20 ng DNA/5 ml. The efficiency of the extraction procedure was also evaluated in a serial dilution of the original 20 ng DNA/5 ml sample. Detectable DNA was extracted when it was at a concentration of 1.28 pg DNA/mL, revealing the high efficiency of this procedure.
Conclusions: This methodology represents a promising tool for schistosomiasis diagnosis utilizing a bio-molecular technique in urine samples which is now ready to be tested under field conditions and may be applicable to the diagnosis of other parasitic disease
T. cruzi OligoC-TesT: A Simplified and Standardized Polymerase Chain Reaction Format for Diagnosis of Chagas Disease
Chagas disease (American trypanosomiasis) is caused by the protozoan parasite Trypanosoma cruzi and represents a major public health problem in Latin America. Furthermore, growing human population movements extend the disease distribution to regions outside the South American continent. Accurate diagnosis is crucial in patient care and in preventing transmission through blood transfusion, organ transplantation, or vertical transmission from mother to child. Routine diagnosis of Trypanosoma cruzi infection generally is based on detection of the host's antibodies against the parasite. However, antibody detection tests are liable to specificity problems and are of limited use in assessing treatment outcome and congenital infections. The introduction of the polymerase chain reaction (PCR) to amplify specific DNA sequences opened promising diagnostic perspectives. Despite its reported high sensitivity and specificity, broad use of the PCR technique in diagnosis of Chagas disease is hampered by its complexity and the lack of any standardization. We here present the development and evaluation of the T. cruzi OligoC-TesT, a simple and standardized dipstick format for detection of PCR amplified T. cruzi DNA. The new tool is an important step towards simplified and standardized molecular diagnosis of Chagas disease
A protease-based biosensor for the detection of schistosome cercariae
Parasitic diseases affect millions of people worldwide, causing debilitating illnesses and death. Rapid and cost-effective approaches to detect parasites are needed, especially in resource-limited settings. A common signature of parasitic diseases is the release of specific proteases by the parasites at multiple stages during their life cycles. To this end, we engineered several modular Escherichia coli and Bacillus subtilis whole-cell-based biosensors which incorporate an interchangeable protease recognition motif into their designs. Herein, we describe how several of our engineered biosensors have been applied to detect the presence and activity of elastase, an enzyme released by the cercarial larvae stage of Schistosoma mansoni. Collectively, S. mansoni and several other schistosomes are responsible for the infection of an estimated 200 million people worldwide. Since our biosensors are maintained in lyophilised cells, they could be applied for the detection of S. mansoni and other parasites in settings without reliable cold chain access
PREVALENCE AND RISK FACTORS OF SCHISTOSOMIASIS AMONG HAUSA COMMUNITIES IN KANO STATE, NIGERIA
SUMMARY Schistosomiasis remains one of the most prevalent neglected tropical diseases especially in Nigeria which has the greatest number of infected people worldwide. A cross-sectional study was conducted among 551 participants from Kano State, North Central Nigeria. Fecal samples were examined for the presence of Schistosoma mansoni eggs using the formalin-ether sedimentation method while the urine samples were examined using the filtration technique for the presence of S. haematobium eggs. Demographic, socioeconomic and environmental information was collected using a pre-validated questionnaire. The overall prevalence of schistosomiasis was 17.8%, with 8.9% and 8.3% infected with S. mansoni and S. haematobium, respectively and 0.5% presenting co-infection with both species. The multiple logistic regression analysis revealed that age < 18 years (OR = 2.13; 95% CI; 1.34- 3.41), presence of infected family members (OR = 3.98; 95% CI; 2.13-7.46), and history of infection (OR = 2.87; 95% CI; 1.87- 4.56) were the significant risk factors associated with schistosomiasis in these communities. In conclusion, this study revealed that schistosomiasis is still prevalent among Hausa communities in Nigeria. Mass drug administration, health education and community mobilization are imperative strategies to significantly reduce the prevalence and morbidity of schistosomiasis in these communities
Interventions for preventing relapse and recurrence of a depressive disorder in children and adolescents
BACKGROUND: Depressive disorders often begin during childhood or adolescence. There is a growing body of evidence supporting effective treatments during the acute phase of a depressive disorder. However, little is known about treatments for preventing relapse or recurrence of depression once an individual has achieved remission or recovery from their symptoms. OBJECTIVES: To determine the efficacy of early interventions, including psychological and pharmacological interventions, to prevent relapse or recurrence of depressive disorders in children and adolescents. SEARCH METHODS: We searched the Cochrane Depression, Anxiety and Neurosis Review Group's Specialised Register (CCDANCTR) (to 1 June 2011). The CCDANCTR contains reports of relevant randomised controlled trials from The Cochrane Library (all years), EMBASE (1974 to date), MEDLINE (1950 to date) and PsycINFO (1967 to date). In addition we handsearched the references of all included studies and review articles. SELECTION CRITERIA: Randomised controlled trials using a psychological or pharmacological intervention, with the aim of preventing relapse or recurrence from an episode of major depressive disorder (MDD) or dysthymic disorder (DD) in children and adolescents were included. Participants were required to have been diagnosed with MDD or DD according to DSM or ICD criteria, using a standardised and validated assessment tool. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed all trials for inclusion in the review, extracted trial and outcome data, and assessed trial quality. Results for dichotomous outcomes are expressed as odds ratio and continuous measures as mean difference or standardised mean difference. We combined results using random-effects meta-analyses, with 95% confidence intervals. We contacted lead authors of included trials and requested additional data where possible. MAIN RESULTS: Nine trials with 882 participants were included in the review. In five trials the outcome assessors were blind to the participants' intervention condition and in the remainder of trials it was unclear. In the majority of trials, participants were either not blind to their intervention condition, or it was unclear whether they were or not. Allocation concealment was also unclear in the majority of trials. Although all trials treated participants in an outpatient setting, the designs implemented in trials was diverse, which limits the generalisability of the results. Three trials indicated participants treated with antidepressant medication had lower relapse-recurrence rates (40.9%) compared to those treated with placebo (66.6%) during a relapse prevention phase (odds ratio (OR) 0.34; 95% confidence interval (CI) 0.18 to 0.64, P = 0.02). One trial that compared a combination of psychological therapy and medication to medication alone favoured a combination approach over medication alone, however this result did not reach statistical significance (OR 0.26; 95% CI 0.06 to 1.15). The majority of trials that involved antidepressant medication reported adverse events including suicide-related behaviours. However, there were not enough data to show which treatment approach results in the most favourable adverse event profile. AUTHORS' CONCLUSIONS: Currently, there is little evidence to conclude which type of treatment approach is most effective in preventing relapse or recurrence of depressive episodes in children and adolescents. Limited trials found that antidepressant medication reduces the chance of relapse-recurrence in the future, however, there is considerable diversity in the design of trials, making it difficult to compare outcomes across studies. Some of the research involving psychological therapies is encouraging, however at present more trials with larger sample sizes need to be conducted in order to explore this treatment approach further
Health care seeking-behaviour of people in Schistosomiasis endemic communities of Ogun and Niger States, Nigeria
A study of the dynamics of health-care seeking-behaviour of people living in communities endemic for schistosomiasis was carried out in Borgu and Shagamu Local Government areas of Niger State and Ewekoro, Odeda and Abeokuta North Local Government Areas of Ogun State, Nigeria. Questionnaires were administered, which was complimented with Focus Group Discussion (FGDs) and in-depth interviews. The study investigated the knowledge, perceptions, beliefs and practices of the people with regards to the signs/symptoms, sources of the infection, actions taken in treating the infection and their preferred health care options. While 64.4% of the 236 respondents identified the river as the source of infection, 67% also mentioned blood in urine, 36.4% mentioned itching and 22.9% mentioned drowsiness as some of the symptoms of the infection: About 59% preferred the orthodox method of treatment and 31.7% preferred both orthodox and traditional methods. It was discovered that the cost of treatment and health education had a significant impact on the respondents' health care seeking-behaviour. Keywords: health, seeking, schistosomiasis, endemic, communities Nigerian Journal of Parasitology Vol. 25, 2005: 121-12
Urinary Schistosomiasis in Asylum Seekers in Italy: An Emergency Currently Undervalued
Despite schistosomiasis is one of the most prevalent tropical diseases in developing countries and and large flows of migrants come from countries where the disease is endemic, imported urinary schistosomiasis is still not easily recognized in non-endemic areas, especially if not subjected to specific investigations. Moreover schistosomiasis is currently not reportable in any European public health system. The data presented in this report were collected were collected between asylum seekers by a simple screening method based on a prior or actual history of a macroscopic hematauria. In case of a history of gross hematuria, the patient underwent to specific exams standardized for the diagnosis of urinary schistosomiasis. Our data show that the prevalence of the disease has been largely underestimated by European Surveillance Systems; in fact in a small population of young asylum seekers coming from endemic areas for schistosomiasis, we found a significant number of individuals with symptomatic disease. Given that the disease typically has an insidious course, it is highly probable that a screening procedure is able to identify early asymptomatic or mildly symptomatic subjects and avoid the serious complications that are present in advanced stages of disease. Given the limits and the costs of a late diagnosis and that an effective treatment is available, subjects from endemic areas should be actively screened for urinary schistosomiasis