scholarly journals Evaluation of the Chagas Western Blot IgG Assay for the Diagnosis of Chagas Disease

Pathogens ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1455
Author(s):  
Jean-Yves Brossas ◽  
Ballering Griselda ◽  
Margarita Bisio ◽  
Jeremy Guihenneuc ◽  
Julián Ernesto Nicolás Gulin ◽  
...  
Keyword(s):  
Western Blot ◽  
Chagas Disease ◽  
Predictive Value ◽  
Protozoan Parasite ◽  
World Health ◽  
Confirmatory Assay ◽  
Health Organization ◽  
Sensitivity Specificity ◽  
Initial Results ◽  
Cruzi Infection

Chagas disease is a debilitating and often fatal pathology resulting from infection by the protozoan parasite Trypanosoma cruzi. In its recommendations, the World Health Organization states that the diagnosis of T. cruzi infection is usually based on the detection of antibodies against T. cruzi antigens and performed with two methodologically different assays. An inconclusive result can be resolved with a third “confirmatory” assay. The objective of this article is to evaluate the effectiveness of the Chagas Western Blot IgG assay (LDBio Diagnostics, Lyon, France) as a confirmatory serologic test. The Chagas Western Blot IgG assay was performed with native antigens derived from a T. cruzi strain of the TcVI genotype. Retrospective sera were provided by two parasitology laboratories (France and Argentina). The sensitivity, specificity, positive predictive value and negative predictive value of the Chagas blot were all 100% in our sera collection. The Chagas blot is an easy and qualitative method for the diagnosis of Chagas disease, with results in less than 2 h. This immunoblot has potential as a supplemental test for the confirmation of the presence of antibodies against T. cruzi in serum specimens. Nonetheless, the very good initial results presented here will need to be confirmed in larger studies.

Indeterminate Chagas’ disease: Trypanosoma cruzi strain and re-infection are factors involved in the progression of cardiopathy

2003 ◽  
Vol 104 (4) ◽  
pp. 415-420 ◽  
Author(s):  
Juan M. BUSTAMANTE ◽  
Héctor W. RIVAROLA ◽  
Alicia R. FERNÁNDEZ ◽  
Julio E. ENDERS ◽  
Ricardo FRETES ◽  
...  
Keyword(s):  
Survival Rate ◽  
Trypanosoma Cruzi ◽  
Chagas Disease ◽  
Infected Group ◽  
World Health ◽  
Cardiac Lesions ◽  
Health Organization ◽  
Host Parasite ◽  
Β Adrenergic Receptors ◽  
First Time

Chagas' disease is caused by Trypanosoma cruzi, which is transmitted by reduviid bugs. The World Health Organization has estimated that about 16–18 million people in the Americas are infected, and that more than 100 million are at risk. In the present study we have used a murine model to analyse if particular T. cruzi strains (Tulahuen strain and SGO-Z12 isolate from a chronic patient) and/or re-infection may determine, during the indeterminate phase of experimental Chagas' disease, changes that could explain the different evolution of cardiac lesions. Re-infected mice reached higher parasitaemias than those infected for the first time. The survival in the indeterminate phase of mice infected with Tulahuen strain was 50.0%, while the SGO-Z12-infected group presented a significantly higher survival rate (77.1%; P<0.01). The SGO-Z12-re-infected group showed a survival rate (70.9%) significantly higher than that of the Tulahuen-re-infected group (37.0%; P<0.01). Electrocardiographic abnormalities were found in 66% of Tulahuen-infected mice, while in SGO-Z12-infected group such abnormalities were found in only 36% of animals (P<0.01). The two groups exhibited similar percentages of electrocardiographic dysfunction on re-infection, although intraventricular blocks were more frequent in Tulahuen-re-infected mice (P<0.01). Hearts from infected or re-infected mice with either parasite showed mononuclear infiltrates. The SGO-Z12-re-infected and Tulahuen-re-infected groups exhibited a significantly diminished affinity (P<0.05) and a significantly increased density (P<0.05) of cardiac β-adrenergic receptors compared with the infected and non-infected groups. The indeterminate phase of Chagas' disease is defined as a prolonged period that is clinically silent, but the present findings show that different T. cruzi strains and re-infection are able to alter the host–parasite equilibrium, and these factors may be responsible for inducing progressive cardiopathy.

scholarly journals Results of Early Virologic Monitoring May Facilitate Differentiated Care Monitoring Strategies for Clients on ART, Rakai, Uganda

2018 ◽  
Vol 5 (10) ◽  
Author(s):  
Victor Ssempijja ◽  
Larry W Chang ◽  
Gertrude Nakigozi ◽  
Anthony Ndyanabo ◽  
Thomas C Quinn ◽  
...  
Keyword(s):  
Predictive Value ◽  
Virologic Failure ◽  
Standard Of Care ◽  
World Health ◽  
Art Initiation ◽  
Cox Proportional Hazard ◽  
Monitoring Strategies ◽  
Cox Proportional Hazard Models ◽  
Health Organization ◽  
Differentiated Care

Abstract Background Viral load (VL) monitoring is standard of care in HIV-infected persons initiated on antiretroviral therapy (ART). We evaluated the predictive value of VL measurements at 6 and 12 months after initiation of firstline ART to estimate the future risk of virologic failure (VF). Methods HIV-infected persons with VL measurements at 6 and 12 months post-ART initiation and at least 2 additional VL measurements thereafter were assessed for risk of future VF, defined per World Health Organization guidelines. VL at 6 or 12 months post-ART was categorized into &lt;400, 400–1000, 1001–2000, and &gt;2000 copies/mL. Cox proportional hazard models were used to compare VF incidence associated with 6-month, 12-month, and a composite of 6- and 12-month VL prediction indicators. Results Overall, 1863 HIV-infected adults had a 6- and 12-month VL measurement, and 1588 had at least 2 additional VLs thereafter for predicting future VF. The majority (67%) were female (median age: females 33 years and males 37 years). At 12 months post-ART, 90% had VL&lt;400 copies/mL (cumulative incidence of VF at 1.5%), 3% had 400–1000 copies/mL (VF 12%), 2% had 1001–2000 copies/mL (VF 22%), and 5% had &gt;2000 copies/mL (VF 71%). The predictive value of the 12-month VL measurement was comparable to the composite of both the 6- and 12-month VL measurements and better than the 6-month VL measurement. Conclusions At 12 months after ART initiation, 90% of patients were virally suppressed with a low likelihood of future VF. VL measurement at 12 months post–ART initiation predicts risk of VF and could inform differentiated virologic monitoring strategies.

scholarly journals Nicho ecológico actual y futuro de la Leishmaniasis (Kinetoplastida: Trypanosomatidae) en la región Neotropical

2016 ◽  
Vol 64 (3) ◽  
Author(s):  
David A. Moo-Llanes
Keyword(s):  
Climate Change ◽  
Visceral Leishmaniasis ◽  
Complex Disease ◽  
Protozoan Parasite ◽  
Neotropical Region ◽  
World Health ◽  
Climate Change Scenarios ◽  
Rcp Scenarios ◽  
Bioclimatic Variables ◽  
Health Organization

The leishmaniasis is a complex disease system, caused by the protozoan parasite Leishmania and transmitted to humans by the vector Lutzomyia spp. Since it is listed as a neglected disease according to the World Health Organization, the aim of this study was to determine the current and future niche of cutaneous and visceral leishmaniasis in the Neotropical region. We built the ecological niche model (ENM) of cutaneous (N= 2 910 occurrences) and visceral (N= 851 occurrences) leishmaniasis using MaxEnt algorithm. Nine bioclimatic variables (BIO1, BIO4, BIO5, BIO6, BIO7, BIO12, BIO13, BIO14, BIO15 (downloaded from the Worldclim) and disease occurrences data were used for the construction of ENM for three periods (current, 2050 and 2070) and four climate change scenarios (RCP 2.6, 4.5, 6.0 y 8.5). We analyzed the number of pixels occupied, identity niche, modified niche (stable, loss, and gain) and seasonality. Our analyses indicated the expansion for cutaneous leishmaniasis (CL), a comparison for visceral leishmaniasis (VL). We rejected the null hypothesis of niche identity between CL and VL with Hellinger’s index = 0.91 (0.92-0.98) and Schoener’s Index = 0.67 (0.85-1.00) but with an overlap niche of 56.3 %. The differences between the two leishmaniasis types were detected in relation to RCP scenarios and niche shifts (area gained / loss). Seasonality was more important for CL. We provided a current picture of CL and VL distributions and the predicted distributional changes associated to different climate change scenarios for the Neotropical region. We can anticipate that increasing range is likely although it will depend locally on the future trends in weather seasonality.

scholarly journals Nucleated Red Blood Cell in Cord Blood as a Marker of Perinatal Asphyxia

2016 ◽  
Vol 35 (3) ◽  
pp. 264-268
Author(s):  
Piush Kanodia ◽  
Nisha Keshary Bhatta ◽  
Rupa Rajbhandari Singh ◽  
Gauri Shankar Shah ◽  
Shankar Prasad Yadav ◽  
...  
Keyword(s):  
Roc Curve ◽  
Predictive Value ◽  
Perinatal Asphyxia ◽  
Rapid Assessment ◽  
World Health ◽  
P Value ◽  
Case Group ◽  
Health Organization ◽  
Normal Neonates ◽  
Control Study

Introduction: Perinatal asphyxia is a common problem with the incidence varying from 0.5 –2% of live births. According to World Health Organization, approximately 4 million babies die each year before they reach the age of one month. The number of NRBC/100 WBC is variable but is rarely greater than 10 in normal neonates. This simple test can be helpful in the rapid assessment of perinatal asphyxia. Material and Methods: This prospective case-control study and there were 82 newborns in Case and 82 newborns in Controls comprising of asphyxiated and nonasphyxiated neonates, respectively, over a period of 12 months. Results: Out of the 82 neonates in case group, fifty nine (59) neonates were found to have NRBC level ≥10/100WBC, out of which 58 (70.7%) were cases and 1(1.2%) was a control. NRBCs count of ≥10/100WBC were seen more in the newborn who had low 5 min Apgar score and in the newborn with severe HIE, these association were statistically significant (P value <0.001). The cut-off NRBC value of ≥10/100WBC also found to have a sensitivity of 70.30% with a specificity of 98.78%. NRBC has a positive predictive value of 98.31% with a negative predictive value of 77.14%. Significance and sensitive area for ROC curve was 0.875. The ROC curve was calculated with cut-off NRBC value of ≥10/100WBC.Conclusions: NRBC counts can be very useful to differentiate HIE newborns from non-HIE newborns which will help in appropriate management and better outcome of these newborns.J Nepal Paediatr Soc 2015;35(3):264-268

A Review of Economic Consequences and Costs of Male Violence Against Women

2019 ◽  
Vol 26 (3) ◽  
pp. 424-434
Author(s):  
M. J. López-Sánchez ◽  
J. A. Belso-Martínez ◽  
J. L. Hervás-Oliver
Keyword(s):  
Domestic Violence ◽  
Violence Against Women ◽  
Economic Consequences ◽  
World Health ◽  
Economic Costs ◽  
Male Violence ◽  
Country Study ◽  
Health Organization ◽  
Domestic Violence And Abuse ◽  
Initial Results

This article focuses on male violence against women. As it takes place in what is often considered to be ‘the private sphere’ of the home, violence is difficult to prove, to measure, to prevent and easy to ignore. A multi-country study (WHO, 2005, WHO multi-country study on women’s health and domestic violence against women: Summary report of initial results on prevalence, health outcomes and women’s responses, Geneva, Switzerland: World Health Organization) shows that there are wide variations between countries resulting in 15 per cent to 71 per cent of women aged between 15 and 49 years saying that they have been victims of physical or sexual violence in intimate relationships. This article reviews and summarises literature that analyse types of economic costs that result from domestic violence and abuse perpetrated against women.

scholarly journals Comparison of body mass index values proposed by Cole et al. (2000) and Must et al. (1991) for identifying obese children with weight-for-height index recommended by the World Health Organization

2003 ◽  
Vol 6 (3) ◽  
pp. 307-311 ◽  
Author(s):  
Marcelo Militão Abrantes ◽  
Joel Alves Lamounier ◽  
Enrico Antônio Colosimo
Keyword(s):  
Body Mass Index ◽  
Body Mass ◽  
World Health ◽  
Overweight Children ◽  
Obese Children ◽  
North East ◽  
Life Pattern ◽  
Definition Of ◽  
Health Organization ◽  
Sensitivity Specificity

AbstractObjectives:To calculate the sensitivity, specificity and agreement of body mass index (BMI) values proposed by Cole et al. (Br. Med. J. 2000; 320: 1) and Must et al. (Am. J. Clin. Nutr. 1991; 53: 839 & 54: 773) with weight-for-height index in the nutritional evaluation of children.Design:Criterion standards for diagnostic tests.Setting:North-east and south-east Brazil.Subjects:Two thousand nine hundred and twenty children studied in Life Pattern Research performed by the Brazilian Institute of Geography and Statistics in 1997. Main outcome measures are the sensitivity, specificity and agreement of BMI values proposed by Must et al. (1991) and Cole et al. (2000).Results:Sensitivity of values proposed by both authors was around 90%. Specificity was almost 100% considering weight-for-height index as the gold standard. The agreement of both values with weight-for-height index, based on kappa results, was good and in pre-school children it was excellent.Conclusions:Values proposed by Cole et al. (2000) and Must et al. (1991) should be used carefully to screen obesity in childhood but can be used to ‘diagnose’ overweight children with a very low chance of having false-positive results. Although the values proposed by both authors performed similarly, use of Cole et al.'s values should be encouraged. The latter cover children from 2 to 6 years old; their values are presented for six-month age intervals; they are based on a larger sample from six different countries; and they are related to the definition of adult obesity.

scholarly journals Capsaicin inhibits arginine kinase and exerts anti-Trypanosoma cruzi activity

2020 ◽  
Author(s):  
Edward A. Valera-Vera ◽  
Chantal Reigada ◽  
Melisa Sayé ◽  
Fabio A. Digirolamo ◽  
Mariana R. Miranda ◽  
...  
Keyword(s):  
Trypanosoma Cruzi ◽  
Chagas Disease ◽  
Stress Responses ◽  
Mammalian Cells ◽  
Arginine Kinase ◽  
Chronic Phase ◽  
New Drugs ◽  
World Health ◽  
Neglected Diseases ◽  
Health Organization

ABSTRACTTrypanosoma cruzi is the causative agent of Chagas disease, considered within the list of twenty neglected diseases according to the World Health Organization. There are only two therapeutic drugs for Chagas disease, both of them unsuitable for the chronic phase, therefore the development of new drugs is a priority.T. cruzi arginine kinase (TcAK) is a promising drug target since it is absent in humans and it is involved in cellular stress responses. In a previous study from our laboratory, possible TcAK inhibitors were identified through computer simulations, resulting in the best-scoring compounds cyanidin derivatives and capsaicin. Considering these results, in this work we evaluate the effect of capsaicin on TcAK activity and its trypanocidal effect. Although capsaicin produced a weak inhibition on the recombinant TcAK activity (IC50 ≈ 800 µM), it had a strong trypanocidal effect on epimastigotes and trypomastigotes (IC50 = 6.26 µM and 0.26 µM, respectively) being 20-fold more active on trypomastigotes than mammalian cells. Epimastigotes that overexpress TcAK were 37% more resistant to capsaicin than wild type parasites, suggesting that trypanocidal activity could be due, in part, to the enzyme inhibition. However, the difference between the concentrations at which the enzyme is inhibited and the parasite death is caused implies the presence of other targets. In this sense, the prohibitin-2 and calmodulin were identified as other possible capsaicin targets. Capsaicin is a strong and selective trypanocidal agent active in nanomolar concentrations, with an IC50 57-fold lower than benznidazole, the drug currently used for treating Chagas disease.

scholarly journals Community Based Chagas Control Program

2018 ◽  
Vol 2 (2) ◽  
Keyword(s):  
Chagas Disease ◽  
Neglected Tropical Diseases ◽  
Control Program ◽  
Poor Quality ◽  
World Health ◽  
Tropical Diseases ◽  
Social Instability ◽  
Main Determinants ◽  
Health Organization ◽  
Effective Transmission

In 2012, World Health Organization published the first ever Neglected Tropical Diseases (NTD) Roadmap, entitled “Accelerating Work to Overcome the Global Impact of Neglected Tropical Diseases: A Roadmap for Implementation.” This report brought international attention to Chagas and other NTDs and provided a framework to guide implementation of policies and strategies set out in the Global Plan to Combat Neglected Tropical Diseases 2008-2015. Chagas disease, endemic to Bolivia, is considered the third most common parasitic disease globally, after malaria and schistosomiasis. It is estimated that six to seven million persons are infected worldwide. [1] Bolivia has the highest rate of endemic Chagas disease in the Americas. Chagas disease is both a disease of poverty and, like other neglected tropical diseases, poverty promoting. [2] Chagas disease is associated with multiple social and environmental determinants in communities marked by poverty. Salient among the main determinants are poor-quality dwellings, social instability, the combined presence of certain environmental factors, such as the Chagas vectors, mammals that serve as reservoirs of the disease and human exposure, creating the conditions for perpetuating the effective transmission of the infection and its endemicity. These challenges put pregnant women, young children and children with disabilities at especially high risk for contracting Chagas disease. Left untreated, Chagas disease can lead to serious heart, digestive and neurological conditions.

Giardia infections

2011 ◽  
Author(s):  
R. C. Andrew Thompson
Keyword(s):  
Transmitted Disease ◽  
Failure To Thrive ◽  
Protozoan Parasite ◽  
Diarrhoeal Disease ◽  
World Health ◽  
Intestinal Protozoan ◽  
Tropical Regions ◽  
Worldwide Distribution ◽  
Health Organization ◽  
Antony Van Leeuwenhoek

Giardia is a ubiquitous intestinal protozoan parasite of vertebrates and the most common intestinal pathogen of humans and domestic animals with a worldwide distribution including both temperate and tropical regions.Giardia was first observed in 1681 by Antony van Leeuwenhoek in his own faeces (Dobell 1920), and the organism has intrigued biologists and clinicians ever since. However, the first detailed description of the parasite was not given until two centuries later by Lambl (1859). Koch’s postulation was proven by Rendtorff in 1954 when he successfully transmitted symptomatic Giardia infection to human volunteers following orally administered cysts. The first symptoms of clinical giardiasis were reported in the early 1920s, although the significance of Giardia as a cause of diarrhoeal disease was controversial for many years (see Farthing 1994; Cox 1998), and it is only recently that the significance of Giardia as a cause of chronic disease in children and its association with failure to thrive, wasting and malabsorption syndromes has been fully realised (reviewed in Farthing 1994; Hall 1994; Gracey 1994; Rabbani and Islam 1994; Hesham et al. 2005; Savioli et al. 2006; Thompson 2008).The question of Giardia ’s role as a source of zoonotically transmitted disease again has been controversial. The World Health Organization (WHO) recommended that Giardia should be considered as a zoonotic agent in 1979 (Anon. 1979). Since that time, increasing circumstantial epidemiological evidence from waterborne outbreaks, the results of some cross-infection experiments and molecular characterization studies of Giardia isolates from humans and other animals has led most authorities to conclude that Giardia should be considered a zoonotic parasite (Acha and Szyfres 2003; Savioli et al. 2006; and reviewed in Thompson 2004). However, as discussed below, the frequency of zoonotic transmission is uncertain.

scholarly journals Qualitative and Quantitative Analysis of IDH1 Mutation in Progressive Gliomas by Allele-Specific qPCR and Western Blot Analysis

2019 ◽  
Vol 18 ◽  
pp. 153303381982839 ◽  
Author(s):  
Moritz Perrech ◽  
Lena Dreher ◽  
Gabriele Röhn ◽  
Pantelis Stavrinou ◽  
Boris Krischek ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Western Blot ◽  
Real Time ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Idh1 Mutation ◽  
World Health ◽  
Chain Reaction ◽  
Polymerase Chain ◽  
Health Organization

To date, diagnosis of IDH1 mutation is based on DNA sequencing and immunohistochemistry, methods limited in terms of sensitivity and ease of use. Recently, the diagnosis of IDH1 mutation by real-time polymerase chain reaction was introduced as an alternative method. In this study, real-time polymerase chain reaction was validated as a tool for detection of IDH1 mutation, and expression levels were analyzed for correlation with course of the disease. A total of 113 tumor samples were obtained intraoperatively from 84 patients with glioma having a diagnosis of diffuse glioma (World Health Organization II), anaplastic glioma (World Health Organization III), secondary glioblastoma ± chemotherapy, primary glioblastoma ± chemotherapy (World Health Organization IV). Tumor samples were snap frozen and processed for sectioning and RNA and protein isolation. Presence of IDH1 mutation was determined by DNA sequencing. Hereafter, quantitative expression of IDH1 messenger RNA was assessed using real-time polymerase chain reaction with specific primers for IDH1 mutation and –wt; protein expression was verified by Western Blot analysis and immunohistochemistry. Additionally, 19 samples of low-grade glioma and their consecutive high-grade glioma were analyzed at different time points of the disease. IDH1 mutation was identified in 63% of samples by DNA sequencing. In correlation with the real-time polymerase chain reaction results, a cutoff value was determined. Above this threshold, sensitivity and specificity of real-time polymerase chain reaction in detecting IDH1 mutation were 98% and 94%, respectively. Quantitative analysis revealed that IDH1 mutation expression is upregulated in secondary glioblastoma (mean ± standard error of mean: 3.52 ± 0.55) compared to lower grade glioma (II = 1.54 ± 0.22; III = 1.67 ± 0.23). In contrast, IDH1 wt expression is upregulated in all glioma grades (concentration >0.1) compared to control brain tissue (0.007 ± 0.0016). Western Blot analysis showed a high concordance to both sequencing and real-time polymerase chain reaction results in qualitative analysis of IDH1 mutation status (specificity 100% and sensitivity 100%). Moreover, semiquantitative protein expression analysis also showed higher expression levels of mutated IDH1 in secondary glioblastoma. In our study, real-time polymerase chain reaction and Western Blot analysis were found to be highly efficient methods in detecting IDH1 mutation in glioma samples. As cost-effective and time-saving methods, real-time polymerase chain reaction and Western Blot analysis may therefore play an important role in IDH1 mutation analysis in the future. IDH1 mutation expression level was found to correlate with the course of disease to a certain extent. Yet, clinical factors as recurrent disease or prior radiochemotherapy did not alter IDH1 mutation expression level.

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