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Sample records for parasitic diseases human

  1. Human Parasitic Diseases in Bulgaria in Between 2013-2014

    Science.gov (United States)

    Rainova, Iskra; Harizanov, Rumen; Kaftandjiev, Iskren; Tsvetkova, Nina; Mikov, Ognyan; Kaneva, Eleonora

    2018-01-01

    Background: In Bulgaria, more than 20 autochthonous human parasitic infections have been described and some of them are widespread. Over 50 imported protozoan and helminthic infections represent diagnostic and therapeutic challenges and pose epidemiological risks due to the possibility of local transmission. Aims: To establish the distribution of autochthonous and imported parasitic diseases among the population of the country over a 2-year period (2013-2014) and to evaluate their significance in the public health system. Study Design: Cross sectional study. Methods: We used the annual reports by regional health inspectorates and data from the National Reference Laboratory at the National Centre of Infectious and Parasitic Diseases on all individuals infected with parasitic diseases in the country. Prevalence was calculated for parasitic diseases with few or absent clinical manifestations (oligosymptomatic or asymptomatic infections). Incidence per 100.000 was calculated for diseases with an overt clinical picture or those that required hospitalisation and specialised medical interventions (e.g. surgery). Results: During the research period, parasitological studies were conducted on 1441.244 persons, and parasitic infections were diagnosed in 22.039 individuals. Distribution of various parasitic pathogens among the population displayed statistically significant differences in prevalence for some intestinal parasites (enterobiasis 0.81%, giardiasis 0.34% and blastocystosis 0.22%). For certain zoonotic diseases such as cystic echinococcosis (average incidence of 3.99 per 100.000) and trichinellosis (average incidence of 0.8 per 100.000), the incidence exceeds several times the annual incidence recorded in the European Union. Conclusion: Parasitic diseases still pose a substantial problem with social and medical impacts on the residents of our country. Improved efficiency regarding autochthonous and imported parasitic diseases is essential in providing the public

  2. Control of human parasitic diseases: Context and overview.

    Science.gov (United States)

    Molyneux, David H

    2006-01-01

    The control of parasitic diseases of humans has been undertaken since the aetiology and natural history of the infections was recognized and the deleterious effects on human health and well-being appreciated by policy makers, medical practitioners and public health specialists. However, while some parasitic infections such as malaria have proved difficult to control, as defined by a sustained reduction in incidence, others, particularly helminth infections can be effectively controlled. The different approaches to control from diagnosis, to treatment and cure of the clinically sick patient, to control the transmission within the community by preventative chemotherapy and vector control are outlined. The concepts of eradication, elimination and control are defined and examples of success summarized. Overviews of the health policy and financing environment in which programmes to control or eliminate parasitic diseases are positioned and the development of public-private partnerships as vehicles for product development or access to drugs for parasite disease control are discussed. Failure to sustain control of parasites may be due to development of drug resistance or the failure to implement proven strategies as a result of decreased resources within the health system, decentralization of health management through health-sector reform and the lack of financial and human resources in settings where per capita government expenditure on health may be less than $US 5 per year. However, success has been achieved in several large-scale programmes through sustained national government investment and/or committed donor support. It is also widely accepted that the level of investment in drug development for the parasitic diseases of poor populations is an unattractive option for pharmaceutical companies. The development of partnerships to specifically address this need provides some hope that the intractable problems of the treatment regimens for the trypanosomiases and

  3. Parasitic diseases

    International Nuclear Information System (INIS)

    Rozenshtraukh, L.S.

    1983-01-01

    Foundations of roentgenological semiotics of parasitic diseases of lungs, w hich are of the greatest practical value, are presented. Roentgenological pictu res of the following parasitic diseases: hydatid and alveolar echinococcosis, pa ragonimiasis, toxoplasmosis, ascariasis, amebiasis, bilharziasis (Schistosomias is) of lungs, are considered

  4. Imaging of parasitic diseases

    International Nuclear Information System (INIS)

    Haddad, Maurice C.

    2008-01-01

    This book provides an overview of the imaging findings of parasitic diseases using modern imaging equipment. The chapters consist of short descriptions of causative pathogens, epidemiology, modes of transmission, pathology, clinical manifestations, laboratory tests, and imaging findings, with illustrative examples of parasitic diseases that can affect various systems of the human body. Tables summarizing key diagnostic features and clinical data pertinent to diagnosis are also included. This book is intended for radiologists worldwide. (orig.)

  5. Imaging of parasitic diseases

    Energy Technology Data Exchange (ETDEWEB)

    Haddad, Maurice C. [American Univ. of Beirut Medical Center (Lebanon). Dept. of Diagnostic Radiology; Abd El Bagi, Mohamed E. [Riyadh Military Hospital (Saudi Arabia). Radiology and Imaging Dept. 920W; Tamraz, Jean C. (eds.) [CHU Hotel-Dieu de France, Beirut (Lebanon)

    2008-07-01

    This book provides an overview of the imaging findings of parasitic diseases using modern imaging equipment. The chapters consist of short descriptions of causative pathogens, epidemiology, modes of transmission, pathology, clinical manifestations, laboratory tests, and imaging findings, with illustrative examples of parasitic diseases that can affect various systems of the human body. Tables summarizing key diagnostic features and clinical data pertinent to diagnosis are also included. This book is intended for radiologists worldwide. (orig.)

  6. Parasitic diseases of lungs

    International Nuclear Information System (INIS)

    Rozenshtraukh, L.C.; Rybakova, N.I.; Vinner, M.G.

    1987-01-01

    Roentgenologic semiotics of the main parasitic diseases of lungs is described: echinococcosis, paragonimiasis, cysticercosis, toxoplasmosis, ascariasis, amebiosis and some rarely met parasitic diseases

  7. [Current situation of human resources of parasitic disease control and prevention organizations in Henan Province].

    Science.gov (United States)

    Ya-Lan, Zhang; Yan-Kun, Zhu; Wei-Qi, Chen; Yan, Deng; Peng, Li

    2018-01-10

    To understand the current status of human resources of parasitic disease control and prevention organizations in Henan Province, so as to provide the reference for promoting the integrative ability of the prevention and control of parasitic diseases in Henan Province. The questionnaires were designed and the method of census was adopted. The information, such as the amounts, majors, education background, technical titles, working years, and turnover in each parasitic disease control and prevention organization was collected by the centers for disease control and prevention (CDCs) at all levels. The data were descriptively analyzed. Totally 179 CDCs were investigated, in which only 19.0% (34/179) had the independent parasitic diseases control institution (department) . There were only 258 full-time staffs working on parasitic disease control and prevention in the whole province, in which only 61.9% (159/258) were health professionals. Those with junior college degree or below in the health professionals accounted for 60.3% (96/159) . Most of them (42.1%) had over 20 years of experience, but 57.9% (92/159) of their technical post titles were at primary level or below. The proportion of the health professionals is low in the parasitic disease control and prevention organizations in Henan Province. The human resource construction for parasitic disease control and prevention at all levels should be strengthened.

  8. [SWOT Analysis of the National Survey on Current Status of Major Human Parasitic Diseases in China].

    Science.gov (United States)

    ZHU, Hui-hui; ZHOU, Chang-hai; CHEN, Ying-dan; ZANG, Wei; XIAO, Ning; ZHOU, Xiao-nong

    2015-10-01

    The National Survey on Current Status of Major Human Parasitic Diseases in China has been carried out since 2014 under the organization of the National Health and Family Planning Commission of the People's Republic of China. The National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (NIPD, China CDC) provided technical support and was responsible for quality control in this survey. This study used SWOT method to analyze the strengths, weaknesses, opportunities and threats that were encountered by he NIPD, China CDC during the completion of the survey. Accordingly, working strategies were proposed to facilitate the future field work.

  9. Children and Parasitic Diseases

    Science.gov (United States)

    ... because they disproportionately affect impoverished people. More on: Neglected Tropical Diseases Prevention One of the most important ways to help prevent these parasitic diseases is to teach children the importance of washing hands correctly with soap ...

  10. Paleoparasitology: the origin of human parasites

    Directory of Open Access Journals (Sweden)

    Adauto Araujo

    2013-09-01

    Full Text Available Parasitism is composed by three subsystems: the parasite, the host, and the environment. There are no organisms that cannot be parasitized. The relationship between a parasite and its host species most of the time do not result in damage or disease to the host. However, in a parasitic disease the presence of a given parasite is always necessary, at least in a given moment of the infection. Some parasite species that infect humans were inherited from pre-hominids, and were shared with other phylogenetically close host species, but other parasite species were acquired from the environment as humans evolved. Human migration spread inherited parasites throughout the globe. To recover and trace the origin and evolution of infectious diseases, paleoparasitology was created. Paleoparasitology is the study of parasites in ancient material, which provided new information on the evolution, paleoepidemiology, ecology and phylogenetics of infectious diseases.

  11. Parasitic Diseases: Glossary

    Science.gov (United States)

    ... of the leg. Endemic: A disease that is native to a particular geographic region. Epidemiology: The study ... parasites/glossary.html) T Telediagnosis: The transmission of digital images captured from a clinical specimen and sent ...

  12. Parasitic, fungal and prion zoonoses: an expanding universe of candidates for human disease.

    Science.gov (United States)

    Akritidis, N

    2011-03-01

    Zoonotic infections have emerged as a burden for millions of people in recent years, owing to re-emerging or novel pathogens often causing outbreaks in the developing world in the presence of inadequate public health infrastructure. Among zoonotic infections, those caused by parasitic pathogens are the ones that affect millions of humans worldwide, who are also at risk of developing chronic disease. The present review discusses the global effect of protozoan pathogens such as Leishmania sp., Trypanosoma sp., and Toxoplasma sp., as well as helminthic pathogens such as Echinococcus sp., Fasciola sp., and Trichinella sp. The zoonotic aspects of agents that are not essentially zoonotic are also discussed. The review further focuses on the zoonotic dynamics of fungal pathogens and prion diseases as observed in recent years, in an evolving environment in which novel patient target groups have developed for agents that were previously considered to be obscure or of minimal significance. © 2011 The Author. Clinical Microbiology and Infection © 2011 European Society of Clinical Microbiology and Infectious Diseases.

  13. The Echinococcus canadensis (G7) genome: a key knowledge of parasitic platyhelminth human diseases.

    Science.gov (United States)

    Maldonado, Lucas L; Assis, Juliana; Araújo, Flávio M Gomes; Salim, Anna C M; Macchiaroli, Natalia; Cucher, Marcela; Camicia, Federico; Fox, Adolfo; Rosenzvit, Mara; Oliveira, Guilherme; Kamenetzky, Laura

    2017-02-27

    The parasite Echinococcus canadensis (G7) (phylum Platyhelminthes, class Cestoda) is one of the causative agents of echinococcosis. Echinococcosis is a worldwide chronic zoonosis affecting humans as well as domestic and wild mammals, which has been reported as a prioritized neglected disease by the World Health Organisation. No genomic data, comparative genomic analyses or efficient therapeutic and diagnostic tools are available for this severe disease. The information presented in this study will help to understand the peculiar biological characters and to design species-specific control tools. We sequenced, assembled and annotated the 115-Mb genome of E. canadensis (G7). Comparative genomic analyses using whole genome data of three Echinococcus species not only confirmed the status of E. canadensis (G7) as a separate species but also demonstrated a high nucleotide sequences divergence in relation to E. granulosus (G1). The E. canadensis (G7) genome contains 11,449 genes with a core set of 881 orthologs shared among five cestode species. Comparative genomics revealed that there are more single nucleotide polymorphisms (SNPs) between E. canadensis (G7) and E. granulosus (G1) than between E. canadensis (G7) and E. multilocularis. This result was unexpected since E. canadensis (G7) and E. granulosus (G1) were considered to belong to the species complex E. granulosus sensu lato. We described SNPs in known drug targets and metabolism genes in the E. canadensis (G7) genome. Regarding gene regulation, we analysed three particular features: CpG island distribution along the three Echinococcus genomes, DNA methylation system and small RNA pathway. The results suggest the occurrence of yet unknown gene regulation mechanisms in Echinococcus. This is the first work that addresses Echinococcus comparative genomics. The resources presented here will promote the study of mechanisms of parasite development as well as new tools for drug discovery. The availability of a high

  14. [A national survey on current status of the important parasitic diseases in human population].

    Science.gov (United States)

    2005-10-30

    In order to understand the current status and trends of the important parasitic diseases in human population, to evaluate the effect of control activities in the past decade and provide scientific base for further developing control strategies, a national survey was carried out in the country (Taiwan, Hongkong and Macau not included) from June, 2001 to 2004 under the sponsorship of the Ministry of Health. The sample sizes of the nationwide survey and of the survey in each province (autonomous region and municipality, P/A/M) were determined following a calculating formula based on an estimation of the sample size of random sampling to the rate of population. A procedure of stratified cluster random sampling was conducted in each province based on geographical location and economical condition with three strata: county/city, township/town, and spot, each spot covered a sample of 500 people. Parasitological examinations were conducted for the infections of soil-transmitted nematodes, Taenia spp, and Clonorchis sinensis, including Kato-Katz thick smear method, scotch cellulose adhesive tape technique and test tube-filter paper culture (for larvae). At the same time, another sampled investigation for Clonorchis sinensis infection was carried out in the known endemic areas in 27 provinces. Serological tests combined with questionnaire and/or clinical diagnosis were applied for hydatid disease, cysticercosis, paragonimiasis, trichinosis, and toxoplasmosis. A total sampled population of 356 629 from the 31 P/A/M was examined by parasitological methods and 26 species of helminth were recorded. Among these helminth, human infections of Metorchis orientalis and Echinostoma aegypti were detected in Fujian Province which seemed to be the first report in the world, and Haplorchis taichui infection in Guangxi Region was the first human infection record in the country. The overall prevalence of helminth infections was 21.74%. The prevalence of soil-transmitted nematodes was 19

  15. Parasitism and calfhood diseases.

    Science.gov (United States)

    Herlich, H; Douvres, F W

    1977-02-01

    That animals can and do acquire an effective immunity against helminth parasites has been demonstrated extensively experimentally, and the fact that domestic animals such as cattle, sheep, and horses become adults while maintaining good health in spite of constant exposure to reinfection long has suggested that immunity must be important to such survival. Although our attempts to date to vaccinate calves against helminth parasites have either failed or been unsatisfactory because of the pathosis induced by the experimental vaccines, the results are not surprising or discouraging. In contrast to the long history of immunization research on bacterial and viral diseases, only within a relatively short time have serious efforts been directed at exploiting hostal immunity for prevention and control of helminthic diseases. Unlike the comparatively simple structures of viruses and bacteria, helminths are complex multicellular animals with vast arrays of antigens and complicated physiological and immunological interactions with their hosts. Much more fundamental information on helminth-bovine interactions, on helminth antigens, and on cattle antibody systems must be developed before progress on control of cattle helminths by vaccination can be meaningful.

  16. The origin and dispersion of human parasitic diseases in the old world (Africa, Europe and Madagascar).

    Science.gov (United States)

    Nozais, Jean-Pierre

    2003-01-01

    The ancestors of present-day man (Homo sapiens sapiens) appeared in East Africa some three and a half million years ago (Australopithecs), and then migrated to Europe, Asia, and later to the Americas, thus beginning the differentiation process. The passage from nomadic to sedentary life took place in the Middle East in around 8000 BC. Wars, spontaneous migrations and forced migrations (slave trade) led to enormous mixtures of populations in Europe and Africa and favoured the spread of numerous parasitic diseases with specific strains according to geographic area. The three human plasmodia (Plasmodium falciparum, P. vivax, and P. malariae) were imported from Africa into the Mediterranean region with the first human migrations, but it was the Neolithic revolution (sedentarisation, irrigation, population increase) which brought about actual foci for malaria. The reservoir for Leishmania infantum and L. donovani--the dog--has been domesticated for thousands of years. Wild rodents as reservoirs of L. major have also long been in contact with man and probably were imported from tropical Africa across the Sahara. L. tropica, by contrast, followed the migrations of man, its only reservoir. L. infantum and L. donovani spread with man and his dogs from West Africa. Likewise, for thousands of years, the dog has played an important role in the spread and the endemic character of hydatidosis through sheep (in Europe and North Africa) and dromadary (in the Sahara and North Africa). Schistosoma haematobium and S. mansoni have existed since prehistoric times in populations living in or passing through the Sahara. These populations then transported them to countries of Northern Africa where the specific, intermediary hosts were already present. Madagascar was inhabited by populations of Indonesian origin who imported lymphatic filariosis across the Indian Ocean (possibly of African origin since the Indonesian sailors had spent time on the African coast before reaching Madagascar

  17. The origin and dispersion of human parasitic diseases in the Old World (Africa, Europe and Madagascar

    Directory of Open Access Journals (Sweden)

    Jean-Pierre Nozais

    2003-01-01

    Full Text Available The ancestors of present-day man (Homo sapiens sapiens appeared in East Africa some three and a half million years ago (Australopithecs, and then migrated to Europe, Asia, and later to the Americas, thus beginning the differentiation process. The passage from nomadic to sedentary life took place in the Middle East in around 8000 BC. Wars, spontaneous migrations and forced migrations (slave trade led to enormous mixtures of populations in Europe and Africa and favoured the spread of numerous parasitic diseases with specific strains according to geographic area. The three human plasmodia (Plasmodium falciparum, P. vivax, and P. malariae were imported from Africa into the Mediterranean region with the first human migrations, but it was the Neolithic revolution (sedentarisation, irrigation, population increase which brought about actual foci for malaria. The reservoir for Leishmania infantum and L. donovani - the dog - has been domesticated for thousands of years. Wild rodents as reservoirs of L. major have also long been in contact with man and probably were imported from tropical Africa across the Sahara. L. tropica, by contrast, followed the migrations of man, its only reservoir. L. infantum and L. donovani spread with man and his dogs from West Africa. Likewise, for thousands of years, the dog has played an important role in the spread and the endemic character of hydatidosis through sheep (in Europe and North Africa and dromadary (in the Sahara and North Africa. Schistosoma haematobium and S. mansoni have existed since prehistoric times in populations living in or passing through the Sahara. These populations then transported them to countries of Northern Africa where the specific, intermediary hosts were already present. Madagascar was inhabited by populations of Indonesian origin who imported lymphatic filariosis across the Indian Ocean (possibly of African origin since the Indonesian sailors had spent time on the African coast before

  18. Women and Parasitic Diseases

    Science.gov (United States)

    ... Consultations, and General Public. Contact Us Parasites Home Women Recommend on Facebook Tweet Share Compartir Infection with ... of parasites can lead to unique consequences for women. Some examples are given below. Infection with Toxoplasma ...

  19. Zoonotic and Non-Zoonotic Diseases in Relation to Human Personality and Societal Values: Support for the Parasite-Stress Model

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    Randy Thornhill

    2010-04-01

    Full Text Available The parasite-stress model of human sociality proposes that humans' ontogenetic experiences with infectious diseases as well as their evolutionary historical interactions with these diseases exert causal influences on human psychology and social behavior. This model has been supported by cross-national relationships between parasite prevalence and human personality traits, and between parasite prevalence and societal values. Importantly, the parasite-stress model emphasizes the causal role of non-zoonotic parasites (which have the capacity for human-to-human transmission, rather than zoonotic parasites (which do not, but previous studies failed to distinguish between these conceptually distinct categories. The present investigation directly tested the differential predictive effects of zoonotic and non-zoonotic (both human-specific and multihost parasite prevalence on personality traits and societal values. Supporting the parasite-stress model, cross-national differences in personality traits (unrestricted sexuality, extraversion, openness to experiences and in societal values (individualism, collectivism, gender equality, democratization are predicted specifically by non-zoonotic parasite prevalence.

  20. Update on pathology of ocular parasitic disease.

    Science.gov (United States)

    Das, Dipankar; Ramachandra, Varsha; Islam, Saidul; Bhattacharjee, Harsha; Biswas, Jyotirmay; Koul, Akanksha; Deka, Panna; Deka, Apurba

    2016-11-01

    Parasites are a group of eukaryotic organisms that may be free-living or form a symbiotic or parasitic relationship with the hosts. Consisting of over 800,000 recognized species, parasites may be unicellular (Protozoa) or multicellular (helminths and arthropods). The association of parasites with human population started long before the emergence of civilization. Parasitic zoonotic diseases are prevalent worldwide including India. Appropriate epidemiological data are lacking on existing zoonotic parasitic diseases, and newer diseases are emerging in our scenario. Systemic diseases such as cysticercosis, paragonimiasis, hydatidosis, and toxoplasmosis are fairly common. Acquired Toxoplasma infections are rising in immune-deficient individuals. Amongst the ocular parasitic diseases, various protozoas such as Cystoidea, trematodes, tissue flagellates, sporozoas etc. affect humans in general and eyes in particular, in different parts of the world. These zoonoses seem to be a real health related problem globally. Recent intensification of research throughout the world has led to specialization in biological fields, creating a conducive situation for researchers interested in this subject. The basics of parasitology lie in morphology, pathology, and with recent updates in molecular parasitology, the scope has extended further. The current review is to address the recent update in ophthalmic parasites with special reference to pathology and give a glimpse of further research in this field.

  1. Update on pathology of ocular parasitic disease

    Directory of Open Access Journals (Sweden)

    Dipankar Das

    2016-01-01

    Full Text Available Parasites are a group of eukaryotic organisms that may be free-living or form a symbiotic or parasitic relationship with the hosts. Consisting of over 800,000 recognized species, parasites may be unicellular (Protozoa or multicellular (helminths and arthropods. The association of parasites with human population started long before the emergence of civilization. Parasitic zoonotic diseases are prevalent worldwide including India. Appropriate epidemiological data are lacking on existing zoonotic parasitic diseases, and newer diseases are emerging in our scenario. Systemic diseases such as cysticercosis, paragonimiasis, hydatidosis, and toxoplasmosis are fairly common. Acquired Toxoplasma infections are rising in immune-deficient individuals. Amongst the ocular parasitic diseases, various protozoas such as Cystoidea, trematodes, tissue flagellates, sporozoas etc. affect humans in general and eyes in particular, in different parts of the world. These zoonoses seem to be a real health related problem globally. Recent intensification of research throughout the world has led to specialization in biological fields, creating a conducive situation for researchers interested in this subject. The basics of parasitology lie in morphology, pathology, and with recent updates in molecular parasitology, the scope has extended further. The current review is to address the recent update in ophthalmic parasites with special reference to pathology and give a glimpse of further research in this field.

  2. Human intestinal parasites in crusader Acre: Evidence for migration with disease in the medieval period.

    Science.gov (United States)

    Mitchell, Piers D; Anastasiou, Evilena; Syon, Danny

    2011-12-01

    The aim of this research is to highlight the role of ancient parasites as evidence for human migration in past populations. The material analysed was soil sediment from the excavation of a medieval cesspool in the city of Acre, in Israel. Archaeological stratigraphy and radiocarbon dating of a fragment of animal bone from the cesspool confirm its use in the 13th century CE, during the crusader period. At that time Acre was located in the Frankish Kingdom of Jerusalem. Soil samples from the cesspool were analysed and eggs of the roundworm (Ascaris lumbricoides) and fish tapeworm (Diphyllobothrium latum) were identified. The fish tapeworm has only been found in the mainland Near East once before, in a latrine of the crusader Order of St. John (Knights Hospitaller). It has been absent in all earlier cesspools, latrines and coprolites so far studied in the region. In contrast to its rarity in the Levant, the fish tapeworm was common in northern Europe during the medieval period. The presence of fish tapeworm eggs in a crusader period cesspool in Acre suggests its use by crusaders or pilgrims from northern Europe who travelled to the Levant carrying these parasites in their intestines. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. Hygiene pests as vectors for parasitic and bacterial diseases in humans

    Science.gov (United States)

    Cholewiński, Marcin; Derda, Monika; Hadaś, Edward

    Diseases transmitted by hygiene pests remain a very serious problem in spite of fast developments in science and medicine. The present study focuses on pests carrying germs that pose a threat to human health and life. The quick pace of life, the need to satisfy human needs and mass production of food sometimes result in flagrant sanitary, hygienic and epidemiological deficiencies. These irregularities are conducive to hygiene pests, which, when not held in check by proper control measures, may act more efficiently and quickly.

  4. In-depth comparative analysis of malaria parasite genomes reveals protein-coding genes linked to human disease in Plasmodium falciparum genome.

    Science.gov (United States)

    Liu, Xuewu; Wang, Yuanyuan; Liang, Jiao; Wang, Luojun; Qin, Na; Zhao, Ya; Zhao, Gang

    2018-05-02

    Plasmodium falciparum is the most virulent malaria parasite capable of parasitizing human erythrocytes. The identification of genes related to this capability can enhance our understanding of the molecular mechanisms underlying human malaria and lead to the development of new therapeutic strategies for malaria control. With the availability of several malaria parasite genome sequences, performing computational analysis is now a practical strategy to identify genes contributing to this disease. Here, we developed and used a virtual genome method to assign 33,314 genes from three human malaria parasites, namely, P. falciparum, P. knowlesi and P. vivax, and three rodent malaria parasites, namely, P. berghei, P. chabaudi and P. yoelii, to 4605 clusters. Each cluster consisted of genes whose protein sequences were significantly similar and was considered as a virtual gene. Comparing the enriched values of all clusters in human malaria parasites with those in rodent malaria parasites revealed 115 P. falciparum genes putatively responsible for parasitizing human erythrocytes. These genes are mainly located in the chromosome internal regions and participate in many biological processes, including membrane protein trafficking and thiamine biosynthesis. Meanwhile, 289 P. berghei genes were included in the rodent parasite-enriched clusters. Most are located in subtelomeric regions and encode erythrocyte surface proteins. Comparing cluster values in P. falciparum with those in P. vivax and P. knowlesi revealed 493 candidate genes linked to virulence. Some of them encode proteins present on the erythrocyte surface and participate in cytoadhesion, virulence factor trafficking, or erythrocyte invasion, but many genes with unknown function were also identified. Cerebral malaria is characterized by accumulation of infected erythrocytes at trophozoite stage in brain microvascular. To discover cerebral malaria-related genes, fast Fourier transformation (FFT) was introduced to extract

  5. Parasite Infection, Carcinogenesis and Human Malignancy

    Directory of Open Access Journals (Sweden)

    Hoang van Tong

    2017-02-01

    Full Text Available Cancer may be induced by many environmental and physiological conditions. Infections with viruses, bacteria and parasites have been recognized for years to be associated with human carcinogenicity. Here we review current concepts of carcinogenicity and its associations with parasitic infections. The helminth diseases schistosomiasis, opisthorchiasis, and clonorchiasis are highly carcinogenic while the protozoan Trypanosoma cruzi, the causing agent of Chagas disease, has a dual role in the development of cancer, including both carcinogenic and anticancer properties. Although malaria per se does not appear to be causative in carcinogenesis, it is strongly associated with the occurrence of endemic Burkitt lymphoma in areas holoendemic for malaria. The initiation of Plasmodium falciparum related endemic Burkitt lymphoma requires additional transforming events induced by the Epstein-Barr virus. Observations suggest that Strongyloides stercoralis may be a relevant co-factor in HTLV-1-related T cell lymphomas. This review provides an overview of the mechanisms of parasitic infection-induced carcinogenicity.

  6. Parasitic Diseases and Psychiatric Illness

    OpenAIRE

    Weiss, Mitchell Gralnick

    1994-01-01

    Distinguishing parasitic diseases from other infections and tropical medical disorders based on microbiological classification is a matter of convenience. Organic brain syndromes are associated with both protozoan and helminthic infections; side-effects of drugs commonly used to treat parasitoses may impair mood and cause anxiety, agitation or psychosis. Emotional states may in turn affect the experience of medical illness. Psychiatrically significant features of medical illness are determine...

  7. Satellite technology and the control of parasitic diseases in Africa ...

    African Journals Online (AJOL)

    The potential application of these techniques in the surveillance, control and prevention of parasitic diseases in Africa is explored in this write-up. Keywords: surveillance, parasitic diseases, satellite techniques, remote sensing, Geographical Information System (GIS), Global Positioning Sytem (GPS), human and robotic, ...

  8. The transcriptome of Trichuris suis--first molecular insights into a parasite with curative properties for key immune diseases of humans.

    Directory of Open Access Journals (Sweden)

    Cinzia Cantacessi

    Full Text Available Iatrogenic infection of humans with Trichuris suis (a parasitic nematode of swine is being evaluated or promoted as a biological, curative treatment of immune diseases, such as inflammatory bowel disease (IBD and ulcerative colitis, in humans. Although it is understood that short-term T. suis infection in people with such diseases usually induces a modified Th2-immune response, nothing is known about the molecules in the parasite that induce this response.As a first step toward filling the gaps in our knowledge of the molecular biology of T. suis, we characterised the transcriptome of the adult stage of this nematode employing next-generation sequencing and bioinformatic techniques. A total of ∼65,000,000 reads were generated and assembled into ∼20,000 contiguous sequences ( = contigs; ∼17,000 peptides were predicted and classified based on homology searches, protein motifs and gene ontology and biological pathway mapping.These analyses provided interesting insights into a number of molecular groups, particularly predicted excreted/secreted molecules (n = 1,288, likely to be involved in the parasite-host interactions, and also various molecules (n = 120 linked to chemokine, T-cell receptor and TGF-β signalling as well as leukocyte transendothelial migration and natural killer cell-mediated cytotoxicity, which are likely to be immuno-regulatory or -modulatory in the infected host. This information provides a conceptual framework within which to test the immunobiological basis for the curative effect of T. suis infection in humans against some immune diseases. Importantly, the T. suis transcriptome characterised herein provides a curated resource for detailed studies of the immuno-molecular biology of this parasite, and will underpin future genomic and proteomic explorations.

  9. Molecular Detection of Rickettsia amblyommii in Amblyomma americanum Parasitizing Humans

    Science.gov (United States)

    2010-01-01

    Detection of Rickettsia amblyommii in Amblyomma americanum Parasitizing Humans Ju Jiang~ Tamasin Yarina~ Melissa K. Miller,2 Ellen Y. Stromdahl? and...protein B gene (ompB) of Rickettsia amblyommii was employed to assess the threat of R. amblyommii exposure to humans parasitized by Amblyomma americanum...infection of and possibly disease in humans. Key Words: Amblyomma americanum-Lone star ticks-Real-time PCR- Rickettsia amblyommii. Introduction R

  10. Parasite Infection, Carcinogenesis and Human Malignancy.

    Science.gov (United States)

    van Tong, Hoang; Brindley, Paul J; Meyer, Christian G; Velavan, Thirumalaisamy P

    2017-02-01

    Cancer may be induced by many environmental and physiological conditions. Infections with viruses, bacteria and parasites have been recognized for years to be associated with human carcinogenicity. Here we review current concepts of carcinogenicity and its associations with parasitic infections. The helminth diseases schistosomiasis, opisthorchiasis, and clonorchiasis are highly carcinogenic while the protozoan Trypanosoma cruzi, the causing agent of Chagas disease, has a dual role in the development of cancer, including both carcinogenic and anticancer properties. Although malaria per se does not appear to be causative in carcinogenesis, it is strongly associated with the occurrence of endemic Burkitt lymphoma in areas holoendemic for malaria. The initiation of Plasmodium falciparum related endemic Burkitt lymphoma requires additional transforming events induced by the Epstein-Barr virus. Observations suggest that Strongyloides stercoralis may be a relevant co-factor in HTLV-1-related T cell lymphomas. This review provides an overview of the mechanisms of parasitic infection-induced carcinogenicity. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  11. Host-Parasite Interaction: Parasite-Derived and -Induced Proteases That Degrade Human Extracellular Matrix

    Directory of Open Access Journals (Sweden)

    Carolina Piña-Vázquez

    2012-01-01

    Full Text Available Parasitic protozoa are among the most important pathogens worldwide. Diseases such as malaria, leishmaniasis, amoebiasis, giardiasis, trichomoniasis, and trypanosomiasis affect millions of people. Humans are constantly threatened by infections caused by these pathogens. Parasites engage a plethora of surface and secreted molecules to attach to and enter mammalian cells. The secretion of lytic enzymes by parasites into host organs mediates critical interactions because of the invasion and destruction of interstitial tissues, enabling parasite migration to other sites within the hosts. Extracellular matrix is a complex, cross-linked structure that holds cells together in an organized assembly and that forms the basement membrane lining (basal lamina. The extracellular matrix represents a major barrier to parasites. Therefore, the evolution of mechanisms for connective-tissue degradation may be of great importance for parasite survival. Recent advances have been achieved in our understanding of the biochemistry and molecular biology of proteases from parasitic protozoa. The focus of this paper is to discuss the role of protozoan parasitic proteases in the degradation of host ECM proteins and the participation of these molecules as virulence factors. We divide the paper into two sections, extracellular and intracellular protozoa.

  12. Bacterial and parasitic diseases of parrots.

    Science.gov (United States)

    Doneley, Robert J T

    2009-09-01

    As wild-caught birds become increasingly rare in aviculture, there is a corresponding decline in the incidence of bacterial and parasitic problems and an increase in the recognition of the importance of maintaining health through better nutrition and husbandry. Nevertheless, the relatively close confines of captivity mean an increased pathogen load in the environment in which companion and aviary parrots live. This increased pathogen load leads to greater exposure of these birds to bacteria and parasites, and consequently a greater risk of infection and disease. This article discusses bacterial and parasitic infections in companion and aviary parrots. It includes the origins, pathogens, diagnosis, treatment, and some of the associated risk factors.

  13. Human Parasites in Medieval Europe: Lifestyle, Sanitation and Medical Treatment.

    Science.gov (United States)

    Mitchell, Piers D

    2015-01-01

    Parasites have been infecting humans throughout our evolution. However, not all people suffered with the same species or to the same intensity throughout this time. Our changing way of life has altered the suitability of humans to infection by each type of parasite. This analysis focuses upon the evidence for parasites from archaeological excavations at medieval sites across Europe. Comparison between the patterns of infection in the medieval period allows us to see how changes in sanitation, herding animals, growing and fertilizing crops, the fishing industry, food preparation and migration all affected human susceptibility to different parasites. We go on to explore how ectoparasites may have spread infectious bacterial diseases, and also consider what medieval medical practitioners thought of parasites and how they tried to treat them. While modern research has shown the use of a toilet decreases the risk of contracting certain intestinal parasites, the evidence for past societies presented here suggests that the invention of latrines had no observable beneficial effects upon intestinal health. This may be because toilets were not sufficiently ubiquitous until the last century, or that the use of fresh human faeces for manuring crops still ensured those parasite species were easily able to reinfect the population. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Vaccines for viral and parasitic diseases produced with baculovirus vectors

    NARCIS (Netherlands)

    Oers, van M.M.

    2006-01-01

    The baculovirus¿insect cell expression system is an approved system for the production of viral antigens with vaccine potential for humans and animals and has been used for production of subunit vaccines against parasitic diseases as well. Many candidate subunit vaccines have been expressed in this

  15. Parasites

    Centers for Disease Control (CDC) Podcasts

    2010-05-06

    In this podcast, a listener wants to know what to do if he thinks he has a parasite or parasitic disease.  Created: 5/6/2010 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 5/6/2010.

  16. Travel/Travelers and Parasitic Diseases

    Science.gov (United States)

    ... of the world and specific country. Many infectious diseases transmitted in food and water can also be acquired directly through the fecal-oral route. Parasitic Illnesses That Can Be Acquired During Travel* From Contaminated Food and Water More ... filariasis African sleeping sickness Onchoceriasis *This list ...

  17. Food-borne human parasitic pathogens associated with household cockroaches and houseflies in Nigeria

    Directory of Open Access Journals (Sweden)

    Oyetunde T. Oyeyemi

    2016-03-01

    Full Text Available Cockroaches and houseflies pose significant public health threat owning to their ability to mechanically transmit human intestinal parasites and other disease-causing microorganisms. This study aims at assessing the vectoral capacity of cockroaches and houseflies in the transmission of human intestinal parasites. Intestinal parasite external surface contamination of 130 cockroaches and 150 houseflies caught within dwelling places in Ilishan-Remo town, Ogun State, Nigeria was determined. Cockroaches (six parasite species were more contaminated than houseflies (four parasite species. The most prevalent parasites were Trichuris trichiura (74.0% and hookworm (63.0% in houseflies and cockroaches respectively. There were significant differences in the prevalence of hookworm, T. trichiura and Taenia spp. isolated from cockroaches and houseflies (P < 0.05. There is high contamination of human intestinal parasites in cockroaches and houseflies in human dwelling places in the study area, thus they have the ability to transmit these parasites to unkempt food materials.

  18. One world health: socioeconomic burden and parasitic disease control priorities.

    Science.gov (United States)

    Torgerson, Paul R

    2013-08-01

    Parasitic diseases present a considerable socio-economic impact to society. Zoonotic parasites can result in a considerable burden of disease in people and substantive economic losses to livestock populations. Ameliorating the effects of these diseases may consist of attempts at eradicating specific diseases at a global level, eliminating them at a national or local level or controlling them to minimise incidence. Alternatively with some parasitic zoonoses it may only be possible to treat human and animal cases as they arise. The choice of approach will be determined by the potential effectiveness of a disease control programme, its cost and the cost effectiveness or cost benefit of undertaking the intervention. Furthermore human disease burden is being increasingly measured by egalitarian non-financial measures which are difficult to apply to livestock. This adds additional challenges to the assessment of socio-economic burdens of zoonotic diseases. Using examples from the group of neglected zoonotic diseases, information regarding the socio-economic effects is reviewed together with how this information is used in decision making with regard to disease control and treatment. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Human fascioliasis: a parasitic health problem in Dakahlia Governorate, Egypt.

    Science.gov (United States)

    el Shazly, A M; Handousa, A E; Youssef, M E; Rizk, H; Hamouda, M M

    1991-08-01

    Fascioliasis has a cosmopolitan distribution and is prevalent in sheep-raising countries. Now, it is an increasingly important parasite of man in the Mediterranean countries. In Dakahlia G., human fascioliasis has imposed itself as a parasitic health problem. In this paper, 23 human cases were selected to throw some light on the signs, symptoms and diagnosis of the disease. It was concluded that painful hepatomegaly, fever, anaemia and marked eosinophilia are tetrad suggesting fascioliasis in patient who has consumed watercress as green salade. Data concerning treatment and follow up will be published later.

  20. Targeted mutagenesis in a human-parasitic nematode

    Science.gov (United States)

    Gang, Spencer S.; Castelletto, Michelle L.

    2017-01-01

    Parasitic nematodes infect over 1 billion people worldwide and cause some of the most common neglected tropical diseases. Despite their prevalence, our understanding of the biology of parasitic nematodes has been limited by the lack of tools for genetic intervention. In particular, it has not yet been possible to generate targeted gene disruptions and mutant phenotypes in any parasitic nematode. Here, we report the development of a method for introducing CRISPR-Cas9-mediated gene disruptions in the human-parasitic threadworm Strongyloides stercoralis. We disrupted the S. stercoralis twitchin gene unc-22, resulting in nematodes with severe motility defects. Ss-unc-22 mutations were resolved by homology-directed repair when a repair template was provided. Omission of a repair template resulted in deletions at the target locus. Ss-unc-22 mutations were heritable; we passed Ss-unc-22 mutants through a host and successfully recovered mutant progeny. Using a similar approach, we also disrupted the unc-22 gene of the rat-parasitic nematode Strongyloides ratti. Our results demonstrate the applicability of CRISPR-Cas9 to parasitic nematodes, and thereby enable future studies of gene function in these medically relevant but previously genetically intractable parasites. PMID:29016680

  1. [Parasitic diseases of the central nervous system].

    Science.gov (United States)

    Schmutzhard, E

    2010-02-01

    Central nervous system infections and infestations by protozoa and helminths constitute a problem of increasing importance throughout all of central European and northern/western countries. This is partially due to the globalisation of our society, tourists and business people being more frequently exposed to parasitic infection/infestation in tropical countries than in moderate climate countries. On top of that, migrants may import chronic infestations and infections with parasitic pathogens, eventually also--sometimes exclusively--involving the nervous system. Knowledge of epidemiology, initial clinical signs and symptoms, diagnostic procedures as well as specific chemotherapeutic therapies and adjunctive therapeutic strategies is of utmost important in all of these infections and infestations of the nervous systems, be it by protozoa or helminths. This review lists, mainly in the form of tables, all possible infections and infestations of the nervous systems by protozoa and by helminths. Besides differentiating parasitic diseases of the nervous system seen in migrants, tourists etc., it is very important to have in mind that disease-related (e.g. HIV) or iatrogenic immunosuppression has led to the increased occurrence of a wide variety of parasitic infections and infestations of the nervous system (e. g. babesiosis, Chagas disease, Strongyloides stercoralis infestation, toxoplasmosis, etc.).

  2. Major parasitic diseases of poverty in mainland China: perspectives for better control.

    Science.gov (United States)

    Wang, Jin-Lei; Li, Ting-Ting; Huang, Si-Yang; Cong, Wei; Zhu, Xing-Quan

    2016-08-01

    Significant progress has been made in the prevention, control, and elimination of human parasitic diseases in China in the past 60 years. However, parasitic diseases of poverty remain major causes of morbidity and mortality, and inflict enormous economic costs on societies.In this article, we review the prevalence rates, geographical distributions, epidemic characteristics, risk factors, and clinical manifestations of parasitic diseases of poverty listed in the first issue of the journal Infectious Diseases of Poverty on 25 October 2012. We also address the challenges facing control of parasitic diseases of poverty and provide suggestions for better control.

  3. [Intestinal parasitic diseases in children].

    Science.gov (United States)

    Mare, Anca; Man, A; Toma, Felicia; Székely, Edit; Lôrinczi, Lilla; Sipoş, Anca

    2007-01-01

    To compare the incidence of intestinal parasitosis between children with residence in urban and rural areas: to compare the efficacy of parasitologic diagnostic methods. In our study we included two lots of children. The first lot consisted in 74 children from rural areas from which we collected 44 samples of feces and 55 samples for the "Scotch tape" test. The second lot consisted in 214 children from urban areas from which we collected 44 samples of feces. We examined each sample of feces by three different methods. The study was performed between April to June 2006. The incidence of intestinal parasitosis increases in children from urban areas towards rural areas, and in children between 5 and 10 years. Ascariasis is the most frequent disease in both urban and rural areas. By examination of each fecal sample by three different methods, the number of positive cases increased. The residence in rural areas and age between 5 to 10 years are risk factors for intestinal parasitosis. The "Scotch tape" test was more efficient in Enterobius vermicularis infection than the methods performed from feces. We recommend using at the same time three diagnostic methods for feces examination to improve the diagnostic sensibility.

  4. The origins of human parasites: Exploring the evidence for endoparasitism throughout human evolution.

    Science.gov (United States)

    Mitchell, Piers D

    2013-09-01

    It is important to determine the origins of human parasites if we are to understand the health of past populations and the effects of parasitism upon human evolution. It also helps us to understand emerging infectious diseases and the modern clinical epidemiology of parasites. This study aims to distinguish those heirloom parasites that have infected humans and their ancestors throughout their evolution in Africa from those recent souvenir species to which humans have only become exposed following contact with animals during their migration across the globe. Ten such heirloom parasites are proposed, which appear to have been spread across the globe. Six further heirlooms are noted to have limited spread due to the constraints of their life cycle. Twelve souvenir parasites of humans are described, along with their animal reservoirs. While the origins of 28 species of endoparasite have been determined, many more species require further assessment once a more systematic analysis of ancient parasites in other regions of Africa has been undertaken. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Human parasitic protozoan infection to infertility: a systematic review.

    Science.gov (United States)

    Shiadeh, Malihe Nourollahpour; Niyyati, Maryam; Fallahi, Shirzad; Rostami, Ali

    2016-02-01

    Protozoan parasitic diseases are endemic in many countries worldwide, especially in developing countries, where infertility is a major burden. It has been reported that such infections may cause infertility through impairment in male and female reproductive systems. We searched Medline, PubMed, and Scopus databases and Google scholar to identify the potentially relevant studies on protozoan parasitic infections and their implications in human and animal model infertility. Literature described that some of the protozoan parasites such as Trichomonas vaginalis may cause deformities of the genital tract, cervical neoplasia, and tubal and atypical pelvic inflammations in women and also non-gonoccocal urethritis, asthenozoospermia, and teratozoospermia in men. Toxopalasma gondii could cause endometritis, impaired folliculogenesis, ovarian and uterine atrophy, adrenal hypertrophy, vasculitis, and cessation of estrus cycling in female and also decrease in semen quality, concentration, and motility in male. Trypanosoma cruzi inhibits cell division in embryos and impairs normal implantation and development of placenta. Decrease in gestation rate, infection of hormone-producing glands, parasite invasion of the placenta, and overproduction of inflammatory cytokines in the oviducts and uterine horns are other possible mechanisms induced by Trypanosoma cruzi to infertility. Plasmodium spp. and Trypanosoma brucei spp. cause damage in pituitary gland, hormonal disorders, and decreased semen quality. Entamoeba histolytica infection leads to pelvic pain, salpingitis, tubo-ovarian abscess, and genital ulcers. Cutaneous and visceral leishmaniasis can induce genital lesion, testicular amyloidosis, inflammation of epididymis, prostatitis, and sperm abnormality in human and animals. In addition, some epidemiological studies have reported that rates of protozoan infections in infertile patients are higher than healthy controls. The current review indicates that protozoan parasitic

  6. Some diseases and parasites of captive woodcocks

    Science.gov (United States)

    Locke, L.N.; Stickel, W.H.; Geis, S.A.

    1965-01-01

    Observations were made concerning the diseases and parasites of a group of woodcocks (Philohela minor) caught in Massachusetts in the summer of 1960 and kept in captivity in Maryland, and of another group caught and kept in Louisiana in the winter of 1960-61. Bumblefoot, a granulomatous swelling of the foot caused by Micrococcus sp., is reported for woodcocks for the first time. Six of 31 woodcocks were infected with a renal coccidium of an undetermined species. Tetrameres sp. was found in 4 of 31 birds examined. Sarcocystis was found in one bird. Aerosaculitis was found in several.

  7. The butterfly effect: parasite diversity, environment, and emerging disease in aquatic wildlife.

    Science.gov (United States)

    Adlard, Robert D; Miller, Terrence L; Smit, Nico J

    2015-04-01

    Aquatic wildlife is increasingly subjected to emerging diseases often due to perturbations of the existing dynamic balance between hosts and their parasites. Accelerating changes in environmental factors, together with anthropogenic translocation of hosts and parasites, act synergistically to produce hard-to-predict disease outcomes in freshwater and marine systems. These outcomes are further complicated by the intimate links between diseases in wildlife and diseases in humans and domestic animals. Here, we explore the interactions of parasites in aquatic wildlife in terms of their biodiversity, their response to environmental change, their emerging diseases, and the contribution of humans and domestic animals to parasitic disease outcomes. This work highlights the clear need for interdisciplinary approaches to ameliorate disease impacts in aquatic wildlife systems. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Parasitic Diseases of Ruminants Brought to Two Zonal Veterinary ...

    African Journals Online (AJOL)

    A five years study (2003-2007) of parasitic diseases of ruminants brought to two Zonal Veterinary clinics located in the Southern part of Niger State, Central Nigeria was carried out to establish disease patterns in cattle, sheep and goats. The study was based on the data extracted from the monthly records of parasitic disease ...

  9. Ancient Human Parasites in Ethnic Chinese Populations.

    Science.gov (United States)

    Yeh, Hui-Yuan; Mitchell, Piers D

    2016-10-01

    Whilst archaeological evidence for many aspects of life in ancient China is well studied, there has been much less interest in ancient infectious diseases, such as intestinal parasites in past Chinese populations. Here, we bring together evidence from mummies, ancient latrines, and pelvic soil from burials, dating from the Neolithic Period to the Qing Dynasty, in order to better understand the health of the past inhabitants of China and the diseases endemic in the region. Seven species of intestinal parasite have been identified, namely roundworm, whipworm, Chinese liver fluke, oriental schistosome, pinworm, Taenia sp. tapeworm, and the intestinal fluke Fasciolopsis buski . It was found that in the past, roundworm, whipworm, and Chinese liver fluke appear to have been much more common than the other species. While roundworm and whipworm remained common into the late 20th century, Chinese liver fluke seems to have undergone a marked decline in its prevalence over time. The iconic transport route known as the Silk Road has been shown to have acted as a vector for the transmission of ancient diseases, highlighted by the discovery of Chinese liver fluke in a 2,000 year-old relay station in northwest China, 1,500 km outside its endemic range.

  10. Parasite-Derived Proteins for the Treatment of Allergies and Autoimmune Diseases

    Directory of Open Access Journals (Sweden)

    Zhenyu Wu

    2017-11-01

    Full Text Available The morbidity associated with atopic diseases and immune dysregulation disorders such as asthma, food allergies, multiple sclerosis, atopic dermatitis, type 1 diabetes mellitus, and inflammatory bowel disease has been increasing all around the world over the past few decades. Although the roles of non-biological environmental factors and genetic factors in the etiopathology have been particularly emphasized, they do not fully explain the increase; for example, genetic factors in a population change very gradually. Epidemiological investigation has revealed that the increase also parallels a decrease in infectious diseases, especially parasitic infections. Thus, the reduced prevalence of parasitic infections may be another important reason for immune dysregulation. Parasites have co-evolved with the human immune system for a long time. Some parasite-derived immune-evasion molecules have been verified to reduce the incidence and harmfulness of atopic diseases in humans by modulating the immune response. More importantly, some parasite-derived products have been shown to inhibit the progression of inflammatory diseases and consequently alleviate their symptoms. Thus, parasites, and especially their products, may have potential applications in the treatment of autoimmune diseases. In this review, the potential of parasite-derived products and their analogs for use in the treatment of atopic diseases and immune dysregulation is summarized.

  11. Parasites of wild animals as a potential source of hazard to humans.

    Science.gov (United States)

    Gałęcki, Remigiusz; Sokół, Rajmund; Koziatek, Sylwia

    2015-01-01

    The decline in wild animal habitats and the uncontrolled growth of their population make these animals come closer to human settlements. The aim of the study was to identify parasitic infections in wild animals in the selected area, and to specify the hazards they create for humans. In more than 66% of the analysed faecal samples from wild boar, hares, roe deer, deer and fallow deer various developmental forms of parasites were found. These included parasites dangerous for humans: Toxocara canis, Capillaria hepatica, Capillaria bovis, Trichuris suis, Trichuris ovis, Trichuris globulosus, Eimeria spp., and Trichostongylus spp. It is necessary to monitor parasitic diseases in wild animals as they can lead to the spread of parasites creating a hazard to humans, pets and livestock.

  12. PARASITES, DISEASES AND DEFORMITIES OF COBIA

    Directory of Open Access Journals (Sweden)

    Ewen McLean

    2008-01-01

    Full Text Available Cobia, Rachycentron canadum, is the only member of the family Rachycentridae (Order Perciformes and as a warm–water fish is to be found in tropical and subtropical waters. The species has been reported in eastern Mediterranean waters and it is likely that in this particular case, cobia are lessespian. Cobia has been farmed in Taiwan since the early 1990s and today nascent cobia aquaculture operations operate throughout South East and Eastern Asia, in Gulf of Mexico and Caribbean Sea as well as in the United States. Many other nations are presently considering adopting cobia as a new species for aquaculture. Production by aquaculture experienced a 7000–fold increase from 1995 to 2005. The increased interest in the species has evolved due in large part to its many excellent characteristics which include good growth, with production of 6 kg live weight fish being possible over a year–long production cycle. Cobia are accepting of pond, net pens and recirculation–based culture; their fillet quality is high and meat delectable; They readily take formulated feeds and respond well to alternate proteins in their diets. Like other species new to aquaculture however, enlarged farming activities have been accompanied by increased incidence of commonly–encountered and emerging diseases. As an aid to current and potential producers as well as researchers, the following provides an overview of the published literature on cobia diseases, parasites and physical deformities.

  13. [Clinical microbiology laboratory and imported parasitic diseases].

    Science.gov (United States)

    Martín-Rabadán, Pablo; Martínez-Ruiz, Rocío; Cuadros, Juan; Cañavate, Carmen

    2010-12-01

    Imported parasitosis represents an increasingly frequent diagnostic challenge for microbiology laboratories. A surge in immigration and international travel has led to a rise in the number of imported cases of parasitosis, and this trend is expected to continue in the future. The present article addresses this challenge by reviewing recommended diagnostic approaches and tests. Currently, microscopy is always recommended when analysing blood samples for parasites. If malaria is suspected, rapid antigen testing (including at least HRP2 antigen) should also be performed. The work-up for suspected leishmaniasis should include serology, culture, and in selected cases detection of antigen in urine. In suspected Chagas disease, two different serological tests should be performed. PCR for blood protozoa is highly sensitive, although it cannot be used to rule out Chagas disease, since this condition may be present without parasitemia. Accurate diagnosis of intestinal amebiasis usually requires PCR or antigen detection tests. In helminthiasis, traditional microscopy may need to be complemented with other tests, such as agar plate culture for strongyloidiasis, Og4C3 antigen detection for bancroftian filariasis, and antibody detection test for filariasis and schistosomiasis. Copyright © 2010 Elsevier España, S.L. All rights reserved.

  14. Disease dynamics in a specialized parasite of ant societies

    DEFF Research Database (Denmark)

    Andersen, Sandra Breum; Ferrari, Matthew; Evans, Harry C.

    2012-01-01

    Coevolution between ant colonies and their rare specialized parasites are intriguing, because lethal infections of workers may correspond to tolerable chronic diseases of colonies, but the parasite adaptations that allow stable coexistence with ants are virtually unknown. We explore the trade......-offs experienced by Ophiocordyceps parasites manipulating ants into dying in nearby graveyards. We used field data from Brazil and Thailand to parameterize and fit a model for the growth rate of graveyards. We show that parasite pressure is much lower than the abundance of ant cadavers suggests...

  15. Disease dynamics in a specialized parasite of ant societies.

    Directory of Open Access Journals (Sweden)

    Sandra B Andersen

    Full Text Available Coevolution between ant colonies and their rare specialized parasites are intriguing, because lethal infections of workers may correspond to tolerable chronic diseases of colonies, but the parasite adaptations that allow stable coexistence with ants are virtually unknown. We explore the trade-offs experienced by Ophiocordyceps parasites manipulating ants into dying in nearby graveyards. We used field data from Brazil and Thailand to parameterize and fit a model for the growth rate of graveyards. We show that parasite pressure is much lower than the abundance of ant cadavers suggests and that hyperparasites often castrate Ophiocordyceps. However, once fruiting bodies become sexually mature they appear robust. Such parasite life-history traits are consistent with iteroparity--a reproductive strategy rarely considered in fungi. We discuss how tropical habitats with high biodiversity of hyperparasites and high spore mortality has likely been crucial for the evolution and maintenance of iteroparity in parasites with low dispersal potential.

  16. Heritability of the human infectious reservoir of malaria parasites.

    Directory of Open Access Journals (Sweden)

    Yaye Ramatoulaye Lawaly

    Full Text Available BACKGROUND: Studies on human genetic factors associated with malaria have hitherto concentrated on their role in susceptibility to and protection from disease. In contrast, virtually no attention has been paid to the role of human genetics in eliciting the production of parasite transmission stages, the gametocytes, and thus enhancing the spread of disease. METHODS AND FINDINGS: We analysed four longitudinal family-based cohort studies from Senegal and Thailand followed for 2-8 years and evaluated the relative impact of the human genetic and non-genetic factors on gametocyte production in infections of Plasmodium falciparum or P. vivax. Prevalence and density of gametocyte carriage were evaluated in asymptomatic and symptomatic infections by examination of Giemsa-stained blood smears and/or RT-PCR (for falciparum in one site. A significant human genetic contribution was found to be associated with gametocyte prevalence in asymptomatic P. falciparum infections. By contrast, there was no heritability associated with the production of gametocytes for P. falciparum or P. vivax symptomatic infections. Sickle cell mutation, HbS, was associated with increased gametocyte prevalence but its contribution was small. CONCLUSIONS: The existence of a significant human genetic contribution to gametocyte prevalence in asymptomatic infections suggests that candidate gene and genome wide association approaches may be usefully applied to explore the underlying human genetics. Prospective epidemiological studies will provide an opportunity to generate novel and perhaps more epidemiologically pertinent gametocyte data with which similar analyses can be performed and the role of human genetics in parasite transmission ascertained.

  17. World Health Organization Estimates of the Global and Regional Disease Burden of 11 Foodborne Parasitic Diseases, 2010 : A Data Synthesis

    NARCIS (Netherlands)

    Torgerson, Paul R; Devleesschauwer, Brecht; Praet, Nicolas; Speybroeck, Niko; Willingham, Arve Lee; Kasuga, Fumiko; Rokni, Mohammad B; Zhou, Xiao-Nong; Fèvre, Eric M; Sripa, Banchob; Gargouri, Neyla; Fürst, Thomas; Budke, Christine M; Carabin, Hélène; Kirk, Martyn D; Angulo, Frederick J; Havelaar, Arie; de Silva, Nilanthi

    2015-01-01

    BACKGROUND: Foodborne diseases are globally important, resulting in considerable morbidity and mortality. Parasitic diseases often result in high burdens of disease in low and middle income countries and are frequently transmitted to humans via contaminated food. This study presents the first

  18. Pets and Parasites

    Science.gov (United States)

    ... good news is that this rarely happens. Most pet-to-people diseases can be avoided by following a few ... your doctor Can a parasite cause death in people and pets? Can human disease from a parasite be treated ...

  19. Anthropogenics: human influence on global and genetic homogenization of parasite populations.

    Science.gov (United States)

    Zarlenga, Dante S; Hoberg, Eric; Rosenthal, Benjamin; Mattiucci, Simonetta; Nascetti, Giuseppe

    2014-12-01

    The distribution, abundance, and diversity of life on Earth have been greatly shaped by human activities. This includes the geographic expansion of parasites; however, measuring the extent to which humans have influenced the dissemination and population structure of parasites has been challenging. In-depth comparisons among parasite populations extending to landscape-level processes affecting disease emergence have remained elusive. New research methods have enhanced our capacity to discern human impact, where the tools of population genetics and molecular epidemiology have begun to shed light on our historical and ongoing influence. Only since the 1990s have parasitologists coupled morphological diagnosis, long considered the basis of surveillance and biodiversity studies, with state-of-the-art tools enabling variation to be examined among, and within, parasite populations. Prior to this time, populations were characterized only by phenotypic attributes such as virulence, infectivity, host range, and geographical location. The advent of genetic/molecular methodologies (multilocus allozyme electrophoresis, polymerase chain reaction-DNA [PCR-DNA] fragments analysis, DNA sequencing, DNA microsatellites, single nucleotide polymorphisms, etc.) have transformed our abilities to reveal variation among, and within, populations at local, regional, landscape, and global scales, and thereby enhanced our understanding of the biosphere. Numerous factors can affect population structure among parasites, e.g., evolutionary and ecological history, mode of reproduction and transmission, host dispersal, and life-cycle complexity. Although such influences can vary considerably among parasite taxa, anthropogenic factors are demonstrably perturbing parasite fauna. Minimal genetic structure among many geographically distinct (isolated) populations is a hallmark of human activity, hastened by geographic introductions, environmental perturbation, and global warming. Accelerating

  20. Taeniasis and Cysticercosis as A Zoonotic Parasitic Disease

    Directory of Open Access Journals (Sweden)

    Sarwitri Endah Estuningsih

    2009-06-01

    Full Text Available Taeniasis is a parasitic disease caused by tapeworms from the genus Taenia, and infection with the larvae form of Taenia is called Cysticercosis. Some species of Taenia are zoonotic, and humans serve as the definitive host, the intermediate host or both. Humans are the definitive hosts for Taenia solium, T. saginata and T. asiatica, however, humans also act as an intermediate host for T. solium and T. asiatica. Animals, such as pigs, are the intermediate host for T. solium and T. asiatica, and cattle are the intermediate host for T. saginata. Humans can be infected by taeniasis when they eat beef or pork that contains larvae (cysticercus. While, cysticercosis is transmitted via food or water contaminated with the eggs of Taenia spp. The transmission may also occur by autoinfection due to lack of hygiene. The diagnosis of taeniasis based on finding the eggs or proglotid in the human feces. For diagnosing cysticercosis in live animals can be done by tongue palpation to find the presence of cysts or nodules. Serological test may also help for diagnosing cysticercosis in humans or animals. Adult tapeworms in the intestine can be killed by anthelmintic and prevention of taeniasis can be conducted by avoiding raw or undercooked pork (T. solium and T. asiatica and beef (T. saginata. Besides that, to prevent the infection of T. solium, T. saginata or T. asiatica, pigs or cattle should not be exposed to human feces.

  1. Diagnostics of parasitic diseases. Myths of the present

    Directory of Open Access Journals (Sweden)

    S. S. Kozlov

    2011-01-01

    Full Text Available Diagnostics of parasitic diseases in many medical laboratories is carried out with a bad quality. Principal causes are the low level of qualification of laboratorians and a small amount of laboratory methods which are used. The majority of practising doctors has bad knowledge about diseases. All this serves as base for occurrence in the market of medical services of various pseudoscientific methods of diagnostics of parasitic diseases, such as Voll-method and its analogues, including a method of bioresonant diagnostics, scanning of the crushed drop of blood, including a dark field method, diagnostics on pulse, detection of toxins of parasites in salivaric crystal amilase and others. These methods cannot be scientific to be the methods of demonstrative medicine often lead to development of parasitic phobias of patients.

  2. THE PARASITIC DISEASES OF MAN IN AFRICA *

    African Journals Online (AJOL)

    wind, and Cd) the existence of forests. ... its incidence seems to vary almost from town to town. It is possible, of ... land and in some parts of Bechuanaland, but in Southern ... In a small survey in ... new dam, and the establishment of irrigation projects spreads ... have been linked with a poor diet, the possibility of a parasitic.

  3. Contemporary models and prospects of control of parasitic diseases

    Directory of Open Access Journals (Sweden)

    Petričević Saša M.

    2007-01-01

    Full Text Available Economic, social and expert-scientific factors determine activities in connection with the development of the control of parasitic infections in the upcoming period of the 21st century. The primary research activities are directed at studies of the physiological functions of parasites and the ecological relations between the parasite and the host, and all that is undertaken with the objective of securing adequate pharmacotherapy/pharmacoprophylaxis and immunoprophilaxis. As there is a huge expansion in the synthesis of chemical compounds, there is a great number of potential substances for use in the form of a medicine. Along these lines, activities concerning the development of new antiparasitics and/or modification of existing ones are primarily based on securing a quality target spot for its action. Another possibility in the area of research is connected to the problem of resistance of parasites and intensive studies of the biochemical-physiological characteristics of parasites, as well as the development of an active epidemiological-episootiological network for monitoring resistance. In parallel with the development of medicines, the results of investigations of physiological functions of parasites and their mutual relations with their host, are intensely used for the development of immunological control, and the development of vaccines (for example, the development of vaccines for the control of coccidiosis, babesiosis, echinococcosis. The second important approach is related to studies of parasitic zoonoses, the effect of global warming on the epidemiological-episootiological characteristics of parasitic diseases and the selection of resistant animal breeds/hybrids. Animal welfare is also of importance, the perfecting of reliable, rapid and less-costly methods for diagnosing parasitic diseases and the development of in vitro methods for the examination of resistance to antiparasitics.

  4. Fascioliasis: a worldwide parasitic disease of importance in travel medicine.

    Science.gov (United States)

    Ashrafi, Keyhan; Bargues, M Dolores; O'Neill, Sandra; Mas-Coma, Santiago

    2014-01-01

    Fascioliasis is a foodborne zoonotic disease caused by the two parasite species Fasciola hepatica and Fasciola gigantica. This trematodiasis has never been claimed special relevance for travellers and migrants. However, the situation has drastically changed in the last two decades, in a way that fascioliasis should today be included in the list of diseases to be enhanced in Travel Medicine. Different kind of travellers have been involved in human infection reports: business travellers, tourists, migrants, expatriated workers, military personnel, religious missionaries, and refugees. Europe is the continent where more imported cases have been reported in many countries. More cases would have been probably reported in Europe if fascioliasis would be a reportable disease. In the Americas, most of the reports concern cases diagnosed in USA. Relative few patients have been diagnosed in studies on travellers performed in Asia. In Africa, most cases were reported in Maghreb countries. Blood eosinophilia and the ingestion of watercress or any other suggestive freshwater plant in anamnesis are extremely useful in guiding towards a fascioliasis diagnosis in a developed country, although may not be so in human endemic areas of developing countries. Several suggestive clinical presentation aspects may be useful, although the clinical polymorphism may be misleading in many cases. Non-invasive techniques are helpful for the diagnosis, although images may lead to confusion. Laparoscopic visualization should assist and facilitate procurement of an accurately guided biopsy. Endoscopic retrograde cholangiopancreatography (ERCP) is the first choice in patients in the chronic phase. ERCP and sphincterotomy are used to extract parasites from the biliary tree. Fluke egg finding continues to be the gold standard and enables for burden quantification and establishing of the drug dose. Many serological and stool antigen detection tests have been developed. Immunological techniques present

  5. [Evaluation on intervention measures of comprehensive control for parasitic diseases in demonstration plot of Xiangyun County].

    Science.gov (United States)

    Wen-Juan, Li; Shao-Rong, Chen; Yan-Hong, Li; Wen, Fang; Chun-Rong, Ke; Li-Bo, Wang

    2011-10-01

    To evaluate the effect of comprehensive intervention measures to control and prevent parasitic diseases in the demonstration plot of Xiangyun County, so as to provide the evidence for establishing appropriate measures of parasitic diseases control and prevention. The baseline data of soil-transmitted nematode infections were obtained in 2006. A series of intervention measures, including health education, deworming, drinking water improvement,latrine improvement, and environment reconstruction, were performed for three years and the effect of the comprehensive intervention measures was evaluated by the national expert group in 2009. The awareness rate of parasitic disease knowledge of residents in 2009 (86.96%) was significantly higher than that in 2006 (35.20%) (Chi2 = 122.95, P transmitted nematode infections, the infection rates of Ascaris lumbricoides in both 2006 and 2009 were the highest and the rates were 18.74% and 2.08%, respectively. In the demonstration plots for parasitic diseases control and prevention of Xiangyun County, the effect of the comprehensive intervention measures which take health education as the forerunner and give priority to control source of parasite infection is remarkable. The measures implemented can achieve the purpose to reduce the infection rates of parasites and improve human health.

  6. Retrospective Study of Epidermal Parasitic Skin Diseases amongst ...

    African Journals Online (AJOL)

    ADOWIE PERE

    ABSTRACT: A ten year retrospective study (1997-2006) was undertaken to determine the prevalence of. Epidermal Parasitic Skin Diseases (EPSD) among out-patients from the skin diseases hospital in Maiduguri, Borno state. Out of 10,000 out-patients examined during the study period, 3527(35.27%) where infected with ...

  7. [Screening of parasitic diseases in the asymptomatic immigrant population].

    Science.gov (United States)

    Goterris, Lidia; Bocanegra, Cristina; Serre-Delcor, Núria; Moure, Zaira; Treviño, Begoña; Zarzuela, Francesc; Espasa, Mateu; Sulleiro, Elena

    2016-07-01

    Parasitic diseases suppose an important health problem in people from high endemic areas, so these must be discarded properly. Usually, these infections develop asymptomatically but, in propitious situations, are likely to reactivate themselves and can cause clinical symptoms and/or complications in the receiving country. Moreover, in some cases it is possible local transmission. Early diagnosis of these parasitic diseases made by appropriate parasitological techniques and its specific treatment will benefit both, the individual and the community. These techniques must be selected according to geoepidemiological criteria, patient's origin, migration route or time spent outside the endemic area; but other factors must also be considered as its sensitivity and specificity, implementation experience and availability. Given the high prevalence of intestinal parasites on asymptomatic immigrants, it is recommended to conduct a study by coproparasitological techniques. Because of its potential severity, the screening of asymptomatic malaria with sensitive techniques such as PCR (polymerase chain reaction) is also advisable. Serological screening for Chagas disease should be performed on all Latin American immigrants, except for people from the Caribbean islands. Other important parasites, which should be excluded, are filariasis and urinary schistosomiasis, by using microscopic examination. The aim of this paper is to review the different techniques for the screening of parasitic diseases and its advices within the care protocols for asymptomatic immigrants. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.

  8. Parasitic diseases of camels in Iran (1931–2017 – a literature review

    Directory of Open Access Journals (Sweden)

    Sazmand Alireza

    2017-01-01

    Full Text Available Parasitic diseases of camels are major causes of impaired milk and meat production, decreases in performance or even death. Some camel parasites also represent a threat to human health. About 171,500 one-humped camels (Camelus dromedarius and 100–300 two-humped camels (Camelus bactrianus live in Iran. Knowledge of the biodiversity of their parasites is still limited. The present review covers all information about camel parasitic diseases in Iran published as dissertations and in both Iranian and international journals from 1931 to February 2017. Ten genera of Protozoa (Trypanosoma, Eimeria, Cryptosporidium, Toxoplasma, Neospora, Sarcocystis, Besnoitia, Theileria, Babesia and Balantidium, 48 helminth species detected in the digestive system, including three species of Trematoda, four species of Cestoda, and 41 species of Nematoda, as well as helminths from other organs – Echinococcus spp., Dictyocaulus filaria, Thelazia leesei, Dipetalonema evansi and Onchocerca fasciata – have so far been described in Iranian camels. Furthermore, 13 species of hard ticks, mange mites, the myiasis flies Cephalopina titillator and Wohlfahrtia magnifica, and immature stages of the Pentastomida Linguatula serrata have also been reported from camels of Iran. Camel parasitic diseases are a major issue in Iran in terms of economics and public health. The present review offers information for an integrated control programme against economically relevant parasites of camels.

  9. Morphological and Molecular Descriptors of the Developmental Cycle of Babesia divergens Parasites in Human Erythrocytes.

    Directory of Open Access Journals (Sweden)

    Ingrid Rossouw

    2015-05-01

    Full Text Available Human babesiosis, especially caused by the cattle derived Babesia divergens parasite, is on the increase, resulting in renewed attentiveness to this potentially life threatening emerging zoonotic disease. The molecular mechanisms underlying the pathophysiology and intra-erythrocytic development of these parasites are poorly understood. This impedes concerted efforts aimed at the discovery of novel anti-babesiacidal agents. By applying sensitive cell biological and molecular functional genomics tools, we describe the intra-erythrocytic development cycle of B. divergens parasites from immature, mono-nucleated ring forms to bi-nucleated paired piriforms and ultimately multi-nucleated tetrads that characterizes zoonotic Babesia spp. This is further correlated for the first time to nuclear content increases during intra-erythrocytic development progression, providing insight into the part of the life cycle that occurs during human infection. High-content temporal evaluation elucidated the contribution of the different stages to life cycle progression. Moreover, molecular descriptors indicate that B. divergens parasites employ physiological adaptation to in vitro cultivation. Additionally, differential expression is observed as the parasite equilibrates its developmental stages during its life cycle. Together, this information provides the first temporal evaluation of the functional transcriptome of B. divergens parasites, information that could be useful in identifying biological processes essential to parasite survival for future anti-babesiacidal discoveries.

  10. Dichotomy in the human CD4+ T-cell response to Leishmania parasites

    DEFF Research Database (Denmark)

    Kemp, M; Kurtzhals, J A; Kharazmi, A

    1994-01-01

    Leishmania parasites cause human diseases ranging from self-healing cutaneous ulcers to fatal systemic infections. In addition, many individuals become infected without developing disease. In mice the two subsets of CD4+ T cells, Th1 and Th2, have different effects on the outcome of experimental...... in humans, and that the balance between subsets of parasite-specific T cells may play an important regulatory role in determining the outcome of the infections....

  11. Dogs, cats, parasites, and humans in Brazil: opening the black box

    Science.gov (United States)

    2014-01-01

    Dogs and cats in Brazil serve as primary hosts for a considerable number of parasites, which may affect their health and wellbeing. These may include endoparasites (e.g., protozoa, cestodes, trematodes, and nematodes) and ectoparasites (i.e., fleas, lice, mites, and ticks). While some dog and cat parasites are highly host-specific (e.g., Aelurostrongylus abstrusus and Felicola subrostratus for cats, and Angiostrongylus vasorum and Trichodectes canis for dogs), others may easily switch to other hosts, including humans. In fact, several dog and cat parasites (e.g., Toxoplasma gondii, Dipylidium caninum, Ancylostoma caninum, Strongyloides stercoralis, and Toxocara canis) are important not only from a veterinary perspective but also from a medical standpoint. In addition, some of them (e.g., Lynxacarus radovskyi on cats and Rangelia vitalii in dogs) are little known to most veterinary practitioners working in Brazil. This article is a compendium on dog and cat parasites in Brazil and a call for a One Health approach towards a better management of some of these parasites, which may potentially affect humans. Practical aspects related to the diagnosis, treatment, and control of parasitic diseases of dogs and cats in Brazil are discussed. PMID:24423244

  12. Criticality of Parasitic Disease Transmission in a Diffusive Population

    International Nuclear Information System (INIS)

    He Minhua; Zhang Duanming; Yin Yanping; Chen Zhiyuan; Pan Guijun

    2008-01-01

    Through using the methods of finite-size effect and short time dynamic scaling, we study the critical behavior of parasitic disease spreading process in a diffusive population mediated by a static vector environment. Through comprehensive analysis of parasitic disease spreading we find that this model presents a dynamical phase transition from disease-free state to endemic state with a finite population density. We determine the critical population density, above which the system reaches an epidemic spreading stationary state. We also perform a scaling analysis to determine the order parameter and critical relaxation exponents. The results show that the model does not belong to the usual directed percolation universality class and is compatible with the class of directed percolation with diffusive and conserved fields

  13. Edible vaccines against veterinary parasitic diseases--current status and future prospects.

    Science.gov (United States)

    Jacob, Siju S; Cherian, Susan; Sumithra, T G; Raina, O K; Sankar, M

    2013-04-08

    Protection of domestic animals against parasitic infections remains a major challenge in most of the developing countries, especially in the surge of drug resistant strains. In this circumstance vaccination seems to be the sole practical strategy to combat parasites. Most of the presently available live or killed parasitic vaccines possess many disadvantages. Thus, expression of parasitic antigens has seen a continued interest over the past few decades. However, only a limited success was achieved using bacterial, yeast, insect and mammalian expression systems. This is witnessed by an increasing number of reports on transgenic plant expression of previously reported and new antigens. Oral delivery of plant-made vaccines is particularly attractive due to their exceptional advantages. Moreover, the regulatory burden for veterinary vaccines is less compared to human vaccines. This led to an incredible investment in the field of transgenic plant vaccines for veterinary purpose. Plant based vaccine trials have been conducted to combat various significant parasitic diseases such as fasciolosis, schistosomosis, poultry coccidiosis, porcine cycticercosis and ascariosis. Besides, passive immunization by oral delivery of antibodies expressed in transgenic plants against poultry coccidiosis is an innovative strategy. These trials may pave way to the development of promising edible veterinary vaccines in the near future. As the existing data regarding edible parasitic vaccines are scattered, an attempt has been made to assemble the available literature. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. 25 CFR 700.723 - Control of livestock disease and parasites.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 2 2010-04-01 2010-04-01 false Control of livestock disease and parasites. 700.723... RELOCATION PROCEDURES New Lands Grazing § 700.723 Control of livestock disease and parasites. Whenever livestock within the New Lands become infected with contagious or infectious disease or parasites or have...

  15. Origin of the human malaria parasite Plasmodium falciparum in gorillas.

    Science.gov (United States)

    Liu, Weimin; Li, Yingying; Learn, Gerald H; Rudicell, Rebecca S; Robertson, Joel D; Keele, Brandon F; Ndjango, Jean-Bosco N; Sanz, Crickette M; Morgan, David B; Locatelli, Sabrina; Gonder, Mary K; Kranzusch, Philip J; Walsh, Peter D; Delaporte, Eric; Mpoudi-Ngole, Eitel; Georgiev, Alexander V; Muller, Martin N; Shaw, George M; Peeters, Martine; Sharp, Paul M; Rayner, Julian C; Hahn, Beatrice H

    2010-09-23

    Plasmodium falciparum is the most prevalent and lethal of the malaria parasites infecting humans, yet the origin and evolutionary history of this important pathogen remain controversial. Here we develop a single-genome amplification strategy to identify and characterize Plasmodium spp. DNA sequences in faecal samples from wild-living apes. Among nearly 3,000 specimens collected from field sites throughout central Africa, we found Plasmodium infection in chimpanzees (Pan troglodytes) and western gorillas (Gorilla gorilla), but not in eastern gorillas (Gorilla beringei) or bonobos (Pan paniscus). Ape plasmodial infections were highly prevalent, widely distributed and almost always made up of mixed parasite species. Analysis of more than 1,100 mitochondrial, apicoplast and nuclear gene sequences from chimpanzees and gorillas revealed that 99% grouped within one of six host-specific lineages representing distinct Plasmodium species within the subgenus Laverania. One of these from western gorillas comprised parasites that were nearly identical to P. falciparum. In phylogenetic analyses of full-length mitochondrial sequences, human P. falciparum formed a monophyletic lineage within the gorilla parasite radiation. These findings indicate that P. falciparum is of gorilla origin and not of chimpanzee, bonobo or ancient human origin.

  16. Targeting NAD+ metabolism in the human malaria parasite Plasmodium falciparum.

    Directory of Open Access Journals (Sweden)

    Jessica K O'Hara

    Full Text Available Nicotinamide adenine dinucleotide (NAD+ is an essential metabolite utilized as a redox cofactor and enzyme substrate in numerous cellular processes. Elevated NAD+ levels have been observed in red blood cells infected with the malaria parasite Plasmodium falciparum, but little is known regarding how the parasite generates NAD+. Here, we employed a mass spectrometry-based metabolomic approach to confirm that P. falciparum lacks the ability to synthesize NAD+ de novo and is reliant on the uptake of exogenous niacin. We characterized several enzymes in the NAD+ pathway and demonstrate cytoplasmic localization for all except the parasite nicotinamidase, which concentrates in the nucleus. One of these enzymes, the P. falciparum nicotinate mononucleotide adenylyltransferase (PfNMNAT, is essential for NAD+ metabolism and is highly diverged from the human homolog, but genetically similar to bacterial NMNATs. Our results demonstrate the enzymatic activity of PfNMNAT in vitro and demonstrate its ability to genetically complement the closely related Escherichia coli NMNAT. Due to the similarity of PfNMNAT to the bacterial enzyme, we tested a panel of previously identified bacterial NMNAT inhibitors and synthesized and screened twenty new derivatives, which demonstrate a range of potency against live parasite culture. These results highlight the importance of the parasite NAD+ metabolic pathway and provide both novel therapeutic targets and promising lead antimalarial compounds.

  17. Diagnosis of Parasitic Diseases: Old and New Approaches

    Directory of Open Access Journals (Sweden)

    Momar Ndao

    2009-01-01

    Full Text Available Methods for the diagnosis of infectious diseases have stagnated in the last 20–30 years. Few major advances in clinical diagnostic testing have been made since the introduction of PCR, although new technologies are being investigated. Many tests that form the backbone of the “modern” microbiology laboratory are based on very old and labour-intensive technologies such as microscopy for malaria. Pressing needs include more rapid tests without sacrificing sensitivity, value-added tests, and point-of-care tests for both high- and low-resource settings. In recent years, research has been focused on alternative methods to improve the diagnosis of parasitic diseases. These include immunoassays, molecular-based approaches, and proteomics using mass spectrometry platforms technology. This review summarizes the progress in new approaches in parasite diagnosis and discusses some of the merits and disadvantages of these tests.

  18. Parasitic Disease in the U.S. Navy

    Science.gov (United States)

    1989-07-21

    Myiass, phthirus, other arthropod, hirudiniasis, other and unspecified. t Ascariasis, strongyloidiasis, trichuriasis, enterobiasis, other nematodes ...combined, laris, is harbored in the fox-vole predator-prey community in Northern latitudes of the United States (14). The duty sta- Results lion of...categories showed frequencies of para- ing those which are most frequent. Two common parasitic sitic disease which were higher than expected (Table 4). Sea

  19. Recognition of Human Erythrocyte Receptors by the Tryptophan-Rich Antigens of Monkey Malaria Parasite Plasmodium knowlesi.

    Directory of Open Access Journals (Sweden)

    Kriti Tyagi

    Full Text Available The monkey malaria parasite Plasmodium knowlesi also infect humans. There is a lack of information on the molecular mechanisms that take place between this simian parasite and its heterologous human host erythrocytes leading to this zoonotic disease. Therefore, we investigated here the binding ability of P. knowlesi tryptophan-rich antigens (PkTRAgs to the human erythrocytes and sharing of the erythrocyte receptors between them as well as with other commonly occurring human malaria parasites.Six PkTRAgs were cloned and expressed in E.coli as well as in mammalian CHO-K1 cell to determine their human erythrocyte binding activity by cell-ELISA, and in-vitro rosetting assay, respectively.Three of six PkTRAgs (PkTRAg38.3, PkTRAg40.1, and PkTRAg67.1 showed binding to human erythrocytes. Two of them (PkTRAg40.1 and PkTRAg38.3 showed cross-competition with each other as well as with the previously described P.vivax tryptophan-rich antigens (PvTRAgs for human erythrocyte receptors. However, the third protein (PkTRAg67.1 utilized the additional but different human erythrocyte receptor(s as it did not cross-compete for erythrocyte binding with either of these two PkTRAgs as well as with any of the PvTRAgs. These three PkTRAgs also inhibited the P.falciparum parasite growth in in-vitro culture, further indicating the sharing of human erythrocyte receptors by these parasite species and the biological significance of this receptor-ligand interaction between heterologous host and simian parasite.Recognition and sharing of human erythrocyte receptor(s by PkTRAgs with human parasite ligands could be part of the strategy adopted by the monkey malaria parasite to establish inside the heterologous human host.

  20. Recognition of Human Erythrocyte Receptors by the Tryptophan-Rich Antigens of Monkey Malaria Parasite Plasmodium knowlesi.

    Science.gov (United States)

    Tyagi, Kriti; Gupta, Deepali; Saini, Ekta; Choudhary, Shilpa; Jamwal, Abhishek; Alam, Mohd Shoeb; Zeeshan, Mohammad; Tyagi, Rupesh K; Sharma, Yagya D

    2015-01-01

    The monkey malaria parasite Plasmodium knowlesi also infect humans. There is a lack of information on the molecular mechanisms that take place between this simian parasite and its heterologous human host erythrocytes leading to this zoonotic disease. Therefore, we investigated here the binding ability of P. knowlesi tryptophan-rich antigens (PkTRAgs) to the human erythrocytes and sharing of the erythrocyte receptors between them as well as with other commonly occurring human malaria parasites. Six PkTRAgs were cloned and expressed in E.coli as well as in mammalian CHO-K1 cell to determine their human erythrocyte binding activity by cell-ELISA, and in-vitro rosetting assay, respectively. Three of six PkTRAgs (PkTRAg38.3, PkTRAg40.1, and PkTRAg67.1) showed binding to human erythrocytes. Two of them (PkTRAg40.1 and PkTRAg38.3) showed cross-competition with each other as well as with the previously described P.vivax tryptophan-rich antigens (PvTRAgs) for human erythrocyte receptors. However, the third protein (PkTRAg67.1) utilized the additional but different human erythrocyte receptor(s) as it did not cross-compete for erythrocyte binding with either of these two PkTRAgs as well as with any of the PvTRAgs. These three PkTRAgs also inhibited the P.falciparum parasite growth in in-vitro culture, further indicating the sharing of human erythrocyte receptors by these parasite species and the biological significance of this receptor-ligand interaction between heterologous host and simian parasite. Recognition and sharing of human erythrocyte receptor(s) by PkTRAgs with human parasite ligands could be part of the strategy adopted by the monkey malaria parasite to establish inside the heterologous human host.

  1. 25 CFR 168.15 - Control of livestock diseases and parasites.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Control of livestock diseases and parasites. 168.15... REGULATIONS FOR THE HOPI PARTITIONED LANDS AREA § 168.15 Control of livestock diseases and parasites. Whenever... parasites or have been exposed thereto, such livestock must be treated and the movement thereof restricted...

  2. Progression of the load of waterborne and intestinal parasitic diseases in the State of Amazonas.

    Science.gov (United States)

    Martins, Marilaine; Lacerda, Marcus Vinícius Guimarães; Monteiro, Wuelton Marcelo; Moura, Marco Antonio Saboia; Santos, Eyde Cristianne Saraiva; Saraceni, Valéria; Saraiva, Maria Graças Gomes

    2015-01-01

    In the State of Amazonas, Brazil, urban expansion together with precarious basic sanitation conditions and human settlement on river banks has contributed to the persistence of waterborne and intestinal parasitic diseases. Time series of the recorded cases of cholera, typhoid fever, hepatitis A and leptospirosis are described, using data from different levels of the surveillance systems. The sources for intestinal parasitosis prevalence data (non-compulsory reporting in Brazil) were Medical Literature Analysis and Retrieval System Online (MEDLINE), Literatura Latino-Americana (LILACS) and the annals of major scientific meetings. Relevant papers and abstracts in all languages were accessed by two independent reviewers. The references cited by each relevant paper were scrutinized to locate additional papers. Despite its initial dissemination across the entire State of Amazonas, cholera was controlled in 1998. The magnitude of typhoid fever has decreased; however, a pattern characterized by eventual outbreaks still remains. Leptospirosis is an increasing cause of concern in association with the annual floods. The overall prevalence of intestinal parasites is high regardless of the municipality and the characteristics of areas and populations. The incidence of hepatitis A has decreased over the past decade. A comparison of older and recent surveys shows that the prevalence of intestinal parasitic diseases has remained constant. The load of waterborne and intestinal parasitic diseases ranks high among the health problems present in the State of Amazonas. Interventions aiming at basic sanitation and vaccination for hepatitis A were formulated and implemented, but assessment of their effectiveness in the targeted populations is still needed.

  3. Counter-insurgents of the blue revolution? Parasites and diseases affecting aquaculture and science.

    Science.gov (United States)

    Blaylock, Reginald B; Bullard, Stephen A

    2014-12-01

    Aquaculture is the fastest-growing segment of food production and is expected to supply a growing portion of animal protein for consumption by humans. Because industrial aquaculture developed only recently compared to industrial agriculture, its development occurred within the context of a growing environmental awareness and acknowledgment of environmental issues associated with industrial farming. As such, parasites and diseases have become central criticisms of commercial aquaculture. This focus on parasites and diseases, however, has created a nexus of opportunities for research that has facilitated considerable scientific advances in the fields of parasitology and aquaculture. This paper reviews Myxobolus cerebralis , Lepeophtheirus salmonis , white spot syndrome virus, and assorted flatworms as select marquee aquaculture pathogens, summarizes the status of the diseases caused by each and their impacts on aquaculture, and highlights some of the significant contributions these pathogens have made to the science of parasitology and aquaculture.

  4. World Health Organization Estimates of the Global and Regional Disease Burden of 11 Foodborne Parasitic Diseases, 2010: A Data Synthesis.

    Directory of Open Access Journals (Sweden)

    Paul R Torgerson

    2015-12-01

    Full Text Available Foodborne diseases are globally important, resulting in considerable morbidity and mortality. Parasitic diseases often result in high burdens of disease in low and middle income countries and are frequently transmitted to humans via contaminated food. This study presents the first estimates of the global and regional human disease burden of 10 helminth diseases and toxoplasmosis that may be attributed to contaminated food.Data were abstracted from 16 systematic reviews or similar studies published between 2010 and 2015; from 5 disease data bases accessed in 2015; and from 79 reports, 73 of which have been published since 2000, 4 published between 1995 and 2000 and 2 published in 1986 and 1981. These included reports from national surveillance systems, journal articles, and national estimates of foodborne diseases. These data were used to estimate the number of infections, sequelae, deaths, and Disability Adjusted Life Years (DALYs, by age and region for 2010. These parasitic diseases, resulted in 48.4 million cases (95% Uncertainty intervals [UI] of 43.4-79.0 million and 59,724 (95% UI 48,017-83,616 deaths annually resulting in 8.78 million (95% UI 7.62-12.51 million DALYs. We estimated that 48% (95% UI 38%-56% of cases of these parasitic diseases were foodborne, resulting in 76% (95% UI 65%-81% of the DALYs attributable to these diseases. Overall, foodborne parasitic disease, excluding enteric protozoa, caused an estimated 23.2 million (95% UI 18.2-38.1 million cases and 45,927 (95% UI 34,763-59,933 deaths annually resulting in an estimated 6.64 million (95% UI 5.61-8.41 million DALYs. Foodborne Ascaris infection (12.3 million cases, 95% UI 8.29-22.0 million and foodborne toxoplasmosis (10.3 million cases, 95% UI 7.40-14.9 million were the most common foodborne parasitic diseases. Human cysticercosis with 2.78 million DALYs (95% UI 2.14-3.61 million, foodborne trematodosis with 2.02 million DALYs (95% UI 1.65-2.48 million and foodborne

  5. THE INCIDENCE OF PARASITIC DISEASES IN LIVESTOCK IN BALI

    Directory of Open Access Journals (Sweden)

    N. A. Suratma

    2012-09-01

    Full Text Available The population of livestock in Bali has continuously increased from year to year. However, some problems are encountered with parasitic infections in livestock. Parasitic infections may be caused by worms, protozoa or ectoparasites. In cattle, the most common infections are those caused by Oesophagostomum sp, Ostertagia sp, Haemonchus sp, Mecistocirrus sp, and Cooperia sp which is the most dominant. Neoascaris vitulorum was reported to be as high as 29.1% in calves. Fascioliasis in cattle was found highly prevalent, between 34.9 to 56.7% and was caused by Fasciola gigantica. Also Paramphistomum infection was reported to be highly prevalent (50.1%. In addition, Boophilus microplus was recorded as high as 36.9%. In goat and sheep, the incidence of Haemonchus contortus was 27.7% and 53.6% respectively. Infestation of Paramphistomum sp in goat was 9.27%. Concerning ectoparasites, Sarcoptes scabiei was reported to be the cause of death of 67% of young goats and up to 11% of older gats in Br. Penginuman, Gilimanuk Negara. Parasitic infections in pigs were caused by Cysticercus tenuicollis (11% and Ascaris suum (24.2% and 21.1% showed Metastrongylus apri and also Sarcoptes scabiei was reported to be the cause of skin disease in pigs. In poultry, parasitic infection were caused by Raillietina (96%, Heterakis gallinae (66.7%, Capillaria sp (6.6%, Ascardia galli (56.7%, Oxyspirura mansoni (50%, Acuaria spiralis (13.3% and Syngamus trachea (3.3%. Multiple infections are common.

  6. [Establishment of response system to emergency parasitic disease affairs in China].

    Science.gov (United States)

    Chun-Li, C; Le-Ping, S; Qing-Biao, H; Bian-Li, X U; Bo, Z; Jian-Bing, L; Dan-Dan, L; Shi-Zhu, L I; Oning, X; Xiao-Nong, Z

    2017-08-14

    China's prevention and control of parasitic diseases has made remarkable achievements. However, the prevalence and transmission of parasitic diseases is impacted by the complicated natural and social factors of environment, natural disasters, population movements, and so on. Therefore, there are still the risks of the outbreak of emergency parasitic diseases affairs, which may affect the control effectiveness of parasitic diseases and endanger the social stability seriously. In this article, we aim at the analysis of typical cases of emergency parasitic disease affairs and their impacts on public health security in China in recently years, and we also elaborate the disposal characteristics of emergency parasitic disease affairs, and propose the establishment of response system to emergency parasitic disease affairs in China, including the organizational structure and response flow path, and in addition, point out that, in the future, we should strengthen the system construction and measures of the response system to emergency parasitic disease affairs, so as to control the risk and harm of parasitic disease spread as much as possible and to realize the early intervention and proper disposal of emergency parasitic disease affairs.

  7. Host behaviour–parasite feedback: an essential link between animal behaviour and disease ecology

    Science.gov (United States)

    Archie, Elizabeth A.; Craft, Meggan E.; Hawley, Dana M.; Martin, Lynn B.; Moore, Janice; White, Lauren

    2016-01-01

    Animal behaviour and the ecology and evolution of parasites are inextricably linked. For this reason, animal behaviourists and disease ecologists have been interested in the intersection of their respective fields for decades. Despite this interest, most research at the behaviour–disease interface focuses either on how host behaviour affects parasites or how parasites affect behaviour, with little overlap between the two. Yet, the majority of interactions between hosts and parasites are probably reciprocal, such that host behaviour feeds back on parasites and vice versa. Explicitly considering these feedbacks is essential for understanding the complex connections between animal behaviour and parasite ecology and evolution. To illustrate this point, we discuss how host behaviour–parasite feedbacks might operate and explore the consequences of feedback for studies of animal behaviour and parasites. For example, ignoring the feedback of host social structure on parasite dynamics can limit the accuracy of predictions about parasite spread. Likewise, considering feedback in studies of parasites and animal personalities may provide unique insight about the maintenance of variation in personality types. Finally, applying the feedback concept to links between host behaviour and beneficial, rather than pathogenic, microbes may shed new light on transitions between mutualism and parasitism. More generally, accounting for host behaviour–parasite feedbacks can help identify critical gaps in our understanding of how key host behaviours and parasite traits evolve and are maintained. PMID:27053751

  8. Host behaviour-parasite feedback: an essential link between animal behaviour and disease ecology.

    Science.gov (United States)

    Ezenwa, Vanessa O; Archie, Elizabeth A; Craft, Meggan E; Hawley, Dana M; Martin, Lynn B; Moore, Janice; White, Lauren

    2016-04-13

    Animal behaviour and the ecology and evolution of parasites are inextricably linked. For this reason, animal behaviourists and disease ecologists have been interested in the intersection of their respective fields for decades. Despite this interest, most research at the behaviour-disease interface focuses either on how host behaviour affects parasites or how parasites affect behaviour, with little overlap between the two. Yet, the majority of interactions between hosts and parasites are probably reciprocal, such that host behaviour feeds back on parasites and vice versa. Explicitly considering these feedbacks is essential for understanding the complex connections between animal behaviour and parasite ecology and evolution. To illustrate this point, we discuss how host behaviour-parasite feedbacks might operate and explore the consequences of feedback for studies of animal behaviour and parasites. For example, ignoring the feedback of host social structure on parasite dynamics can limit the accuracy of predictions about parasite spread. Likewise, considering feedback in studies of parasites and animal personalities may provide unique insight about the maintenance of variation in personality types. Finally, applying the feedback concept to links between host behaviour and beneficial, rather than pathogenic, microbes may shed new light on transitions between mutualism and parasitism. More generally, accounting for host behaviour-parasite feedbacks can help identify critical gaps in our understanding of how key host behaviours and parasite traits evolve and are maintained. © 2016 The Author(s).

  9. Proteins involved in invasion of human red blood cells by malaria parasites

    Directory of Open Access Journals (Sweden)

    Ewa Jaśkiewicz

    2010-11-01

    Full Text Available Malaria is a disease caused by parasites of Plasmodium species. It is responsible for around 1-2 million deaths annually, mainly children under the age of 5. It occurs mainly in tropical and subtropical areas.Malaria is caused by five Plasmodium species:[i] P. falciparum, P. malariae, P. vivax, P. knowlesi[/i] and [i]P. ovale[/i]. Mosquitoes spread the disease by biting humans. The malaria parasite has two stages of development: the human stage and the mosquito stage. The first stage occurs in the human body and is divided into two phases: the liver phase and the blood phase.The invasion of erythrocytes by [i]Plasmodium[/i] merozoites is a multistep process of specific protein interactions between the parasite and red blood cell. The first step is the reversible merozoite attachment to the erythrocyte followed by its apical reorientation, then formation of an irreversible “tight” junction and finally entry into the red cell in a parasitophorous vacuole.The blood phase is supported by a number of proteins produced by the parasite. The merozoite surface GPI-anchored proteins (MSP-1, 2, 4, 5, 8 and 10 assist in the process of recognition of susceptible erythrocytes, apical membrane antigen (AMA-1 may be directly responsible for apical reorientation of the merozoite and apical proteins which function in tight junction formation. These ligands are members of two families: Duffy binding-like (DBL and reticulocyte binding-like (RBL proteins. In [i]Plasmodium[/i] [i]falciparum[/i] the DBL family includes: EBA-175, EBA-140 (BAEBL, EBA-181 (JESEBL, EBA-165 (PEBL and EBL-1 ligands.To date, no effective antimalarial vaccine has been developed, but there are several studies for this purpose. Therefore, it is crucial to understand the molecular basis of host cells invasion by parasites. Major efforts are focused on developing a multiantigenic and multiepitope vaccine preventing all steps of [i]Plasmodium[/i] invasion.

  10. Chlorophyllin as a possible measure against vectors of human parasites and fish parasites

    Directory of Open Access Journals (Sweden)

    Peter Rolf Richter

    2014-06-01

    Full Text Available Water soluble chlorophyll (chlorophyllin exerts pronounced photodynamic activity. Chlorophyllin is a potential remedy against mosquito larvae and aquatic stages in the life cycle of parasites as well as against ectoparasites in fish. In the recent years it was found that mosquito larvae and other pest organisms can be killed by means of photodynamic substances such as different porphyrin derivates (e.g. hematoporphyrin, meso-tri(N-methylpyridyl, meso-mono(N-tetra-decylpyridyl porphyrine, hematoporphyrin IX, or hermatoporphyrin formula (HPF. It was found that incubation of mosquito larvae in chlorophyllin solution and subsequent irradiation results in photodynamic destruction of the larvae. Incorporation of about 8 ng chlorophyllin per larvae was sufficient to induce its death. In fish mass cultivation ichthyophthiriosis is a severe parasitic protozoan disease caused by the ciliate Ichthyophthirius multifiliis. It was found that incubation of infected fishes in chlorophyllin and subsequent illumination reduced the number of trophonts significantly (more than 50 %. The fishes were not impaired. Chlorophyllin and other photodynamic substances may become a possible countermeasure against I. multifiliis and other ectoparasites in aquaculture. The effectiveness of chlorophyllin depends on light attenuation in the water body.

  11. Parasitic Nematode Interactions with Mammals and Plants

    NARCIS (Netherlands)

    Jasmer, D.P.; Goverse, A.; Smant, G.

    2003-01-01

    Parasitic nematodes that infect humans, animals, and plants cause serious diseases that are deleterious to human health and agricultural productivity. Chemical and biological control methods have reduced the impact of these parasites. However, surviving environmental stages lead to persistent

  12. Emerging Animal Parasitic Diseases: A Global Overview and Appropriate Strategies for their Monitoring and Surveillance in Nigeria.

    Science.gov (United States)

    Atehmengo, Ngongeh L; Nnagbo, Chiejina S

    2014-01-01

    Emerging animal parasitic diseases are reviewed and appropriate strategies for efficient monitoring and surveillance in Nigeria are outlined. Animal and human parasitic infections are distinguished. Emerging diseases have been described as those diseases that are being recognised for the first time or diseases that are already recorded but their frequency and/or geographic range is being increased tremendously. Emergence of new diseases may be due to a number of factors such as the spread of a new infectious agent, recognition of an infection that has been in existence but undiagnosed, or when it is realised that an established disease has an infectious origin. The terms could also be used to describe the resurgence of a known infection after its incidence had been known to have declined. Emerging infections are compounding the control of infectious diseases and huge resources are being channeled to alleviate the rising challenge. The diseases are numerous and include helminth, protozoal / rickettsial and entomological. A list of parasitic emerging diseases in Nigeria is included. Globally occurring emerging parasitic diseases are also outlined. Emerging and re-emerging infections can be brought about by many factors including climate change and global warming, changes in biodiversity, population mobility, movement of animals, globalisation of commerce/trade and food supply, social and cultural factors such as food eating habits, religious beliefs, farming practices, trade of infected healthy animals, reduction in the available land for animals, immune-suppressed host and host density and misuse or over use of some drugs leading to drug resistance.

  13. Prophylactic Antiparasitic Transgenesis for Human Parasitic Disease?

    Czech Academy of Sciences Publication Activity Database

    Lukeš, Julius; Raper, J.

    2010-01-01

    Roč. 18, č. 10 (2010), s. 1745-1747 ISSN 1525-0016 Institutional research plan: CEZ:AV0Z60220518 Keywords : TRYPANOSOME LYTIC FACTOR * GENE-THERAPY * IMMUNODEFICIENCY Subject RIV: EB - Genetic s ; Molecular Biology Impact factor: 7.149, year: 2010

  14. New mechanisms of disease and parasite-host interactions.

    Science.gov (United States)

    de Souza, Tiago Alves Jorge; de Carli, Gabriel Jose; Pereira, Tiago Campos

    2016-09-01

    An unconventional interaction between a patient and parasites was recently reported, in which parasitic cells invaded host's tissues, establishing several tumors. This finding raises various intriguing hypotheses on unpredicted forms of interplay between a patient and infecting parasites. Here we present four unusual hypothetical host-parasite scenarios with intriguing medical consequences. Relatively simple experimental designs are described in order to evaluate such hypotheses. The first one refers to the possibility of metabolic disorders in parasites intoxicating the host. The second one is on possibility of patients with inborn errors of metabolism (IEM) being more resistant to parasites (due to accumulation of toxic compounds in the bloodstream). The third one refers to a mirrored scenario: development of tumors in parasites due to ingestion of host's circulating cancer cells. The last one describes a complex relationship between parasites accumulating a metabolite and supplying it to a patient with an IEM. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. [Progress of research on genetic engineering antibody and its application in prevention and control of parasitic diseases].

    Science.gov (United States)

    Yao, Yuan; Yu, Chuan-xin

    2013-08-01

    Antibody has extensive application prospects in the biomedical field. The inherent disadvantages of traditional polyclonal antibody and monoclonal antibody limit their application values. The humanized and fragmented antibody remodeling has given a rise to a series of genetic engineered antibody variant. This paper reviews the progress of research on genetic engineering antibody and its application in prevention and control of parasitic diseases.

  16. Progression of the load of waterborne and intestinal parasitic diseases in the State of Amazonas

    Directory of Open Access Journals (Sweden)

    Marilaine Martins

    2015-06-01

    Full Text Available In the State of Amazonas, Brazil, urban expansion together with precarious basic sanitation conditions and human settlement on river banks has contributed to the persistence of waterborne and intestinal parasitic diseases. Time series of the recorded cases of cholera, typhoid fever, hepatitis A and leptospirosis are described, using data from different levels of the surveillance systems. The sources for intestinal parasitosis prevalence data (non-compulsory reporting in Brazil were Medical Literature Analysis and Retrieval System Online (MEDLINE, Literatura Latino-Americana (LILACS and the annals of major scientific meetings. Relevant papers and abstracts in all languages were accessed by two independent reviewers. The references cited by each relevant paper were scrutinized to locate additional papers. Despite its initial dissemination across the entire State of Amazonas, cholera was controlled in 1998. The magnitude of typhoid fever has decreased; however, a pattern characterized by eventual outbreaks still remains. Leptospirosis is an increasing cause of concern in association with the annual floods. The overall prevalence of intestinal parasites is high regardless of the municipality and the characteristics of areas and populations. The incidence of hepatitis A has decreased over the past decade. A comparison of older and recent surveys shows that the prevalence of intestinal parasitic diseases has remained constant. The load of waterborne and intestinal parasitic diseases ranks high among the health problems present in the State of Amazonas. Interventions aiming at basic sanitation and vaccination for hepatitis A were formulated and implemented, but assessment of their effectiveness in the targeted populations is still needed.

  17. Human Environmental Disease Network

    DEFF Research Database (Denmark)

    Taboureau, Olivier; Audouze, Karine

    2017-01-01

    During the past decades, many epidemiological, toxicological and biological studies have been performed to assess the role of environmental chemicals as potential toxicants for diverse human disorders. However, the relationships between diseases based on chemical exposure have been rarely studied...... by computational biology. We developed a human environmental disease network (EDN) to explore and suggest novel disease-disease and chemical-disease relationships. The presented scored EDN model is built upon the integration on systems biology and chemical toxicology using chemical contaminants information...... and their disease relationships from the reported TDDB database. The resulting human EDN takes into consideration the level of evidence of the toxicant-disease relationships allowing including some degrees of significance in the disease-disease associations. Such network can be used to identify uncharacterized...

  18. The Impact of Cultural Behaviours, Local Beliefs, and Practices on Emerging Parasitic Diseases in Tropical Africa

    Science.gov (United States)

    Onwuliri, Celestine O. E.; Anosike, Jude C.; Oguoma, Chibuzor; Onwuliri, Viola A.; Nwoke, Betram E. B.; Dozie, Ikechukwu, N. S.; Iwuala, Moses O. E.

    2005-01-01

    The scourge of emerging parasitic diseases (e.g., urinary schistosomiasis, ascariasis, malaria, chagas disease, leishmaniasis, trachoma, trichiuriasis, taeniasis, dracunculiasis, sleeping sickness, filariasis) causes tremendous pain, suffering, and eventually death in tropical African communities. Patterns of transmission of these emerging…

  19. Using a One Health approach to assess the impact of parasitic disease in livestock: how does it add value?

    Science.gov (United States)

    Rushton, Jonathan; Bruce, Mieghan

    2017-01-01

    Human population increases, with greater food demands, have resulted in a rapid evolution of livestock food systems, leading to changes in land and water use. The scale of global livestock systems mean that changes in animal health status, particularly in parasite levels, have impacts that go beyond farm and sector levels. To quantify the true impact of parasites in livestock, frameworks that look at both resources and services valued in markets and those that have no true market value are required. Mitigating the effects of parasitic disease in livestock will not only increase productivity, but also improve animal welfare and human health, whilst reducing the environmental burden of livestock production systems. To measure these potential benefits, a One Health approach is needed. This paper discusses the types of methods and the data collection tools needed for a more holistic perspective and provides a framework with its application to coccidiosis in poultry. To build a body of knowledge that allows the ranking of parasite diseases in a wider animal health setting, such One Health frameworks need to be applied more frequently and with rigour. The outcome will improve the allocation of resources to critical constraints on parasite management.

  20. Environmental risk and toxicology of human and veterinary waste pharmaceutical exposure to wild aquatic host-parasite relationships.

    Science.gov (United States)

    Morley, Neil J

    2009-03-01

    Pollution of the aquatic environment by human and veterinary waste pharmaceuticals is an increasing area of concern but little is known about their ecotoxicological effects on wildlife. In particular the interactions between pharmaceuticals and natural stressors of aquatic communities remains to be elucidated. A common natural stressor of freshwater and marine organisms are protozoan and metazoan parasites, which can have significant effects on host physiology and population structure, especially under the influence of many traditional kinds of toxic pollutants. However, little is known about the effects of waste pharmaceuticals to host-parasite dynamics. In order to assess the risk waste pharmaceuticals pose to aquatic wildlife it has been suggested the use of toxicological data derived from mammals during the product development of pharmaceuticals may be useful for predicting toxic effects. An additional similar source of information is the extensive clinical studies undertaken with numerous classes of drugs against parasites of human and veterinary importance. These studies may form the basis of preliminary risk assessments to aquatic populations and their interactions with parasitic diseases in pharmaceutical-exposed habitats. The present article reviews the effects of the most common classes of pharmaceutical medicines to host-parasite relationships and assesses the risk they may pose to wild aquatic organisms. In addition the effects of pharmaceutical mixtures, the importance of sewage treatment, and the risk of developing resistant strains of parasites are also assessed. Copyright © 2008 Elsevier B.V. All rights reserved.

  1. Tapeworm Diphyllobothrium dendriticum (Cestoda)-Neglected or Emerging Human Parasite?

    Czech Academy of Sciences Publication Activity Database

    Kuchta, Roman; Brabec, Jan; Kubáčková, P.; Scholz, Tomáš

    2013-01-01

    Roč. 7, č. 12 (2013), e2535 ISSN 1935-2727 R&D Projects: GA ČR GAP506/12/1632 Institutional support: RVO:60077344 Keywords : tapeworm * human disease * cox1 gene Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 4.716, year: 2011

  2. Use of radiations and radioisotopes for investigating problems connected with parasitic diseases of animals in India

    International Nuclear Information System (INIS)

    Tewari, H.C.; Singh, K.S.

    1979-01-01

    The status of the present knowledge regarding the use of isotopes and radiations for studies of animal parasitic diseases in India is reviewed. The concepts in immunology of metazoan parasites with relevance to vaccination have been discussed. A brief review of radiation attenuated vaccines against certain economically important species of helminth parasites and the use of radioisotopes for pathophysiological investigations and for the study of anthelmintic activity is given. (auth.)

  3. Anthropogenics: Human influence on global and genetic homogenization of parasite populations

    Science.gov (United States)

    The distribution, abundance, and diversity of life on Earth have been greatly shaped by human activities. This is no truer than in the geographic expansion of parasites; however, measuring the extent to which humans have influenced the dissemination and population structure of parasites has been cha...

  4. Parasites and fungi as risk factors for human and animal health.

    Science.gov (United States)

    Góralska, Katarzyna; Błaszkowska, Joanna

    2015-01-01

    Recent literature data suggests that parasitic and fungal diseases, which pose a threat to both human and animal health, remain a clinical, diagnostic and therapeutic problem. Attention is increasingly paid to the role played by natural microbiota in maintaining homeostasis in humans. A particular emphasis is placed on the possibility of manipulating the human microbiota (permanent, transient, pathogenic) and macrobiota (e.g., Trichuris suis) to support the treatment of selected diseases such as Crohn's disease, obesity, diabetes and cancer. Emphasis is placed on important medical species whose infections not only impair health but can also be life threatening, such as Plasmodium falciparum, Echinococcus multilocularis and Baylisascaris procyonis, which expand into areas which have so far been uninhabited. This article also presents the epidemiology, diagnosis and treatment of opportunistic parasitoses imported from the tropics, which spread across large groups of people through human-to-human transmission (Enterobius vermicularis, Sarcoptes scabiei). It also discusses the problem of environmentally-conditioned parasitoses, particularly their etiological factors associated with food contaminated with invasive forms (Trichinella sp., Toxoplasma gondii). The analysis also concerns the presence of developmental forms of geohelminths (Toxocara sp.) and ectoparasites (ticks), which are vectors of serious human diseases (Lyme borreliosis, anaplasmosis, babesiosis), in the environment. Mycological topics contains rare cases of mycoses environmentally conditioned (CNS aspergillosis) and transmissions of these pathogens in a population of hospitalized individuals, as well as seeking new methods used to treat mycoses.

  5. Impacts of parasite infection on columnaris disease of tilapia

    Science.gov (United States)

    There is no information available on whether parasite infection will increase the susceptibility of tilapia to Flavobacterium columnare and whether parasite treatment could improve fish survival after F. columnare exposure. Two trials were conducted to evaluate 1) the susceptibility of hybrid tilapi...

  6. Genetic characterization of human-pathogenic Cyclospora cayetanensis parasites from three endemic regions at the 18S ribosomal RNA locus.

    Science.gov (United States)

    Sulaiman, Irshad M; Ortega, Ynes; Simpson, Steven; Kerdahi, Khalil

    2014-03-01

    Cyclospora cayetanensis is an apicocomplexan parasite that infects the gastrointestinal tract and causes acute diarrheal disease in humans. In recent years, this human-pathogenic parasite has led to several foodborne outbreaks in the United States and Canada, mostly associated with imported produce. Understanding the biology and epidemiology of C. cayetanensis is difficult because little is known about its origin, possible zoonotic reservoirs, and genetic relationships with other coccidian parasites. Recently, we developed a 70kDa heat shock protein (HSP70) gene based nested PCR protocol for detection of C. cayetanensis parasite and sequenced the PCR products of 16 human isolates from Nepal, Mexico, and Peru. In this study, we have characterized the regions of 18S ribosomal RNA (rRNA) gene of 17 human C. cayetanensis isolates for molecular detection, and also to ascertain the genetic diversity of this parasite. The 18S rRNA primer sets were further tested by PCR amplification followed by nucleotide sequencing of the PCR amplified products of previously characterized C. cayetanensis isolates from three endemic regions at HSP70 locus. Although no genetic polymorphism was observed at the regions of HSP70 locus characterized in our previous study, the data analysis of this study revealed a minor genetic diversity at the 18S rRNA locus among the C. cayetanensis isolates. The 18S rRNA gene-based nested PCR protocol provides a useful genetic marker for the detection of C. cayetanensis parasite and confirms it as a genetically distinct species in genus Cyclospora. The results also supported lack of geographic segregation and existence of genetically homogeneous population for the C. cayetanensis parasites both at the HSP70 as well as at the18S rRNA loci. Published by Elsevier B.V.

  7. Helminth parasites of cats from the Vientiane Province, Laos, as indicators of the occurrence of causative agents of human parasitoses

    Directory of Open Access Journals (Sweden)

    Scholz T.

    2003-12-01

    Full Text Available A total of 55 domestic cats (Felis calus f. domestico and one wild (Bengal cat (Prionailurus bengalensis from the Vientiane Province, central Laos, were examined for helminth parasites with emphasis given to potential human parasites. The following species were found (parasites infective to man marked with an asterisk: Opisthorchis viverrini*, Haplorchis pumilio*,H. laichui*,H. yokogawai*, Stellantchasmus falcatus* (Digenea; Spirometra sp.*, Dipylidium caninum*, Taenia taeniaeformis (Cestoda; Capillariidae gen. sp., Toxocara canis*, T. cati*, Ancylostoma ceylanicum*, A. tubaeforme, Gnathostoma spinigerum*, Physaloptera preputials (Nematoda; and Oncicola sp. (Acanthocephala. This study demonstrated that examination of cats may provide useful data on the occurrence of helminths which are potential causative agents of human diseases.

  8. Mitosis in the Human Malaria Parasite Plasmodium falciparum ▿

    OpenAIRE

    Gerald, Noel; Mahajan, Babita; Kumar, Sanjai

    2011-01-01

    Malaria is caused by intraerythrocytic protozoan parasites belonging to Plasmodium spp. (phylum Apicomplexa) that produce significant morbidity and mortality, mostly in developing countries. Plasmodium parasites have a complex life cycle that includes multiple stages in anopheline mosquito vectors and vertebrate hosts. During the life cycle, the parasites undergo several cycles of extreme population growth within a brief span, and this is critical for their continued transmission and a contri...

  9. The economic impact of diseases and parasitic problems in freshwater fish production

    OpenAIRE

    Okaeme, A.N.; Obiekezie, A.I.; Ogbondeminu, F.S.

    1987-01-01

    Diseases and parasitic problems could constitute significant economic losses in fish production if not controlled, thus the need to continue monitoring its prevalence. Based on field studies on feral and intensively raised fish at the Kainji Lake Research Institute Nigeria, some diseases and parasitic problems have been identified. These include; helminthiasis; fungal disease; protozoa which include Myxosoma sp., Myxobolus spp., Henneguya sp., Trichodina sp., Ichthopthrius sp. bacterial mainl...

  10. Intestinal Parasitic Infections in Human Immunodeficiency Virus-Infected and Noninfected Persons in a High Human Immunodeficiency Virus Prevalence Region of Cameroon.

    Science.gov (United States)

    Nkenfou, Céline Nguefeu; Tchameni, Sandrine Mboula; Nkenfou, Carine Nguefeu; Djataou, Patrice; Simo, Ulrich Florian; Nkoum, Alexandre Benjamin; Estrin, William

    2017-09-01

    The problem of intestinal parasitic infection in human immunodeficiency virus (HIV)-infected people requires careful consideration in the developing world where poor nutrition is associated with poor hygiene and several coinfecting diseases. Studies have addressed this issue in Cameroon, especially in the low HIV prevalence area. The current study was conducted to determine the prevalence of intestinal parasitosis in people living with HIV (PLHIV) in Adamaoua and to identify associated risk factors. Stool and blood specimens from study participants were screened for intestinal parasites and anti-HIV antibodies, respectively. Of 235 participants, 68 (28.9%) were HIV positive, 38 of them on antiretroviral treatment (ART). The overall prevalence of intestinal parasites was 32.3%. Of 68 PLHIV, 32.3% (22/68) were infected with intestinal parasites, compared with 32.3% (54/167) of the HIV-negative patients. Univariate analysis showed no difference between the prevalence of intestinal parasites among PLHIV and HIV-negative patients ( P = 0.69). ART was not associated with the prevalence of intestinal parasites. Multivariate analysis showed that the quality of water and the personal hygiene were the major risk factors associated to intestinal parasitosis. The level of education was associated with HIV serostatus: the higher the level of education, the lower the risk of being infected with HIV ( P = 0.00). PLHIV and the general population should be screened routinely for intestinal parasites and treated if infected.

  11. Species-specific escape of Plasmodium sporozoites from oocysts of avian, rodent, and human malarial parasites.

    Science.gov (United States)

    Orfano, Alessandra S; Nacif-Pimenta, Rafael; Duarte, Ana P M; Villegas, Luis M; Rodrigues, Nilton B; Pinto, Luciana C; Campos, Keillen M M; Pinilla, Yudi T; Chaves, Bárbara; Barbosa Guerra, Maria G V; Monteiro, Wuelton M; Smith, Ryan C; Molina-Cruz, Alvaro; Lacerda, Marcus V G; Secundino, Nágila F C; Jacobs-Lorena, Marcelo; Barillas-Mury, Carolina; Pimenta, Paulo F P

    2016-08-02

    Malaria is transmitted when an infected mosquito delivers Plasmodium sporozoites into a vertebrate host. There are many species of Plasmodium and, in general, the infection is host-specific. For example, Plasmodium gallinaceum is an avian parasite, while Plasmodium berghei infects mice. These two parasites have been extensively used as experimental models of malaria transmission. Plasmodium falciparum and Plasmodium vivax are the most important agents of human malaria, a life-threatening disease of global importance. To complete their life cycle, Plasmodium parasites must traverse the mosquito midgut and form an oocyst that will divide continuously. Mature oocysts release thousands of sporozoites into the mosquito haemolymph that must reach the salivary gland to infect a new vertebrate host. The current understanding of the biology of oocyst formation and sporozoite release is mostly based on experimental infections with P. berghei, and the conclusions are generalized to other Plasmodium species that infect humans without further morphological analyses. Here, it is described the microanatomy of sporozoite escape from oocysts of four Plasmodium species: the two laboratory models, P. gallinaceum and P. berghei, and the two main species that cause malaria in humans, P. vivax and P. falciparum. It was found that sporozoites have species-specific mechanisms of escape from the oocyst. The two model species of Plasmodium had a common mechanism, in which the oocyst wall breaks down before sporozoites emerge. In contrast, P. vivax and P. falciparum sporozoites show a dynamic escape mechanism from the oocyst via polarized propulsion. This study demonstrated that Plasmodium species do not share a common mechanism of sporozoite escape, as previously thought, but show complex and species-specific mechanisms. In addition, the knowledge of this phenomenon in human Plasmodium can facilitate transmission-blocking studies and not those ones only based on the murine and avian models.

  12. Emerging Animal Parasitic Diseases: A Global Overview and Appropriate Strategies for their Monitoring and Surveillance in Nigeria

    Science.gov (United States)

    Atehmengo, Ngongeh L; Nnagbo, Chiejina S

    2014-01-01

    Emerging animal parasitic diseases are reviewed and appropriate strategies for efficient monitoring and surveillance in Nigeria are outlined. Animal and human parasitic infections are distinguished. Emerging diseases have been described as those diseases that are being recognised for the first time or diseases that are already recorded but their frequency and/or geographic range is being increased tremendously. Emergence of new diseases may be due to a number of factors such as the spread of a new infectious agent, recognition of an infection that has been in existence but undiagnosed, or when it is realised that an established disease has an infectious origin. The terms could also be used to describe the resurgence of a known infection after its incidence had been known to have declined. Emerging infections are compounding the control of infectious diseases and huge resources are being channeled to alleviate the rising challenge. The diseases are numerous and include helminth, protozoal / rickettsial and entomological. A list of parasitic emerging diseases in Nigeria is included. Globally occurring emerging parasitic diseases are also outlined. Emerging and re-emerging infections can be brought about by many factors including climate change and global warming, changes in biodiversity, population mobility, movement of animals, globalisation of commerce/trade and food supply, social and cultural factors such as food eating habits, religious beliefs, farming practices, trade of infected healthy animals, reduction in the available land for animals, immune-suppressed host and host density and misuse or over use of some drugs leading to drug resistance. PMID:25328553

  13. HOW HUMAN HISTORY HAS INFLUENCED GEOGRAPHY AND GENETICS OF PARASITE POPULATIONS

    Science.gov (United States)

    Human beings have radically altered agricultural landscapes, establishing a limited repertoire of plants and animals over vast expanses. Here, I consider what impact such a history may have had on the distribution and diversity of animal parasite, hypothesizing that certain parasites may have been '...

  14. A preface on advances in diagnostics for infectious and parasitic diseases: detecting parasites of medical and veterinary importance.

    Science.gov (United States)

    Stothard, J Russell; Adams, Emily

    2014-12-01

    There are many reasons why detection of parasites of medical and veterinary importance is vital and where novel diagnostic and surveillance tools are required. From a medical perspective alone, these originate from a desire for better clinical management and rational use of medications. Diagnosis can be at the individual-level, at close to patient settings in testing a clinical suspicion or at the community-level, perhaps in front of a computer screen, in classification of endemic areas and devising appropriate control interventions. Thus diagnostics for parasitic diseases has a broad remit as parasites are not only tied with their definitive hosts but also in some cases with their vectors/intermediate hosts. Application of current diagnostic tools and decision algorithms in sustaining control programmes, or in elimination settings, can be problematic and even ill-fitting. For example in resource-limited settings, are current diagnostic tools sufficiently robust for operational use at scale or are they confounded by on-the-ground realities; are the diagnostic algorithms underlying public health interventions always understood and well-received within communities which are targeted for control? Within this Special Issue (SI) covering a variety of diseases and diagnostic settings some answers are forthcoming. An important theme, however, throughout the SI is to acknowledge that cross-talk and continuous feedback between development and application of diagnostic tests is crucial if they are to be used effectively and appropriately.

  15. Fasciolopsiasis: Endemic focus of a neglected parasitic disease in Bihar

    Directory of Open Access Journals (Sweden)

    A Achra

    2015-01-01

    Full Text Available Purpose: To describe a newly discovered, previously unreported endemic focus of fasciolopsiasis in the Phulwaria village, under tehsil Sugauli, East Champaran, Bihar. Materials and Methods: A study was conducted at village Phulwaria, following diagnosis of fasciolopsiasis in three children from the village. A total of 120 individuals, including all the children and adults who gave history of recent passage of red fleshy masses in their stool, were included in the study. The cases of fasciolopsiasis were treated with Praziquantel 25 mg/kg, three doses a day. Risk factors for the transmission of the parasite in the village were also studied. Results: Questionnaire revealed majority of the population suffering from abdominal discomfort and passage of red fleshy masses in stool. These fleshy masses were identified as Fasciolopsis buski. One hundred and eighteen individuals were presumably considered as cases of the parasitic infection. After treatment with Praziquantel, all of them passed the parasite in their stool for the next 2-3 days. On investigating, it was observed that all the conditions required for effective continuation of the life cycle of the parasite were present in this village. Conclusion: This study draws attention to a new endemic focus of fasciolopsiasis in Bihar, with a very high prevalence due to poverty, the lack of awareness about the parasite in villagers as well as ignorance among local medical practitioners. There is an urgent need for mass campaign around the region for its effective control.

  16. Gastrointestinal parasites of canids, a latent risk to human health in Tunisia.

    Science.gov (United States)

    Oudni-M'rad, Myriam; Chaâbane-Banaoues, Raja; M'rad, Selim; Trifa, Fatma; Mezhoud, Habib; Babba, Hamouda

    2017-06-05

    Although data on the parasite environmental contamination are crucial to implement strategies for control and treatment, information about zoonotic helminths is very limited in Tunisia. Contamination of areas with canid faeces harboring infective parasite elements represents a relevant health-risk impact for humans. The aim of this study was to assess the environmental contamination with eggs and oocysts of gastrointestinal parasites of dogs and wild canids in Tunisia with special attention to those that can be transmitted to humans. One thousand two hundred and seventy faecal samples from stray dogs and 104 from wild canids (red foxes and golden jackals) were collected from different geographical regions throughout Tunisia. The helminth eggs and protozoan oocysts were concentrated by sucrose flotation and identified by microscopic examination. The most frequently observed parasites in dog samples were Toxocara spp. (27.2%), E. granulosus (25.8%), and Coccidia (13.1%). For wild canid faeces, the most commonly encountered parasites were Toxocara spp. (16.3%) followed by Capillaria spp. (9.6%). The parasite contamination of dog faeces varied significantly from one region to another in function of the climate. To our knowledge, the study highlights for the first time in Tunisia a serious environmental contamination by numerous parasitic stages infective to humans. Efforts should be made to increase the awareness of the contamination risk of such parasites in the environment and implement a targeted educational program.

  17. Successful Feeding of Amblyomma coelebs (Acari: Ixodidae) Nymphs on Humans in Brazil: Skin Reactions to Parasitism.

    Science.gov (United States)

    Garcia, Marcos V; Matias, Jaqueline; Aguirre, AndrÉ De A R; Csordas, Barbara G; SzabÓ, Matias P J; Andreotti, Renato

    2015-03-01

    Identifying the tick species that successfully feed on humans would increase knowledge of the epidemiology of several tick-borne diseases. These species salivate into the host, increasing the risk of pathogen transmission. However, there is a lack of data in the literature regarding the ticks that prefer to feed on humans. Herein, we describe the successful feeding of Amblyomma coelebs Neumann nymphs on two of the authors after accidental tick bites occurred during field surveys in two preserved areas of Mato Grosso do Sul, Brazil. One of the host-parasite interactions was closely monitored, and the tick development, gross host skin alterations, and related sensations are presented. © The Author 2015. Published by Oxford University Press on behalf of Entomological Society of America.

  18. The pathogenesis of Chagas' disease: when autoimmune and parasite-specific immune responses meet

    Directory of Open Access Journals (Sweden)

    MILENA B. P. SOARES

    2001-12-01

    Full Text Available Chagas' disease is a major health problem in Latin America, where it constitutes one of the leading causes of heart failure. About one fourth of Trypanosoma cruzi-infected individuals develop chronic chagasic cardiomyopathy (CChC, the most severe form of the disease. CChC is histologically characterized by the presence of multifocal inflammatory infiltrates in the heart, composed mainly by mononuclear cells, usually adhered to myocytes and leading to myocytolysis, and frequently by interstitial fibrosis. The pathogenesis of CChC is still unclear, despite intense investigations both in human beings and in animal models of the disease. Although tissue parasitism is rare in the chronic phase of infection, an immune response targeted to persistent parasites or parasite antigens is suggested, by some authors, as the pathogenic mechanism of CChC. Other researchers affirm that the lack of correlation between tissue parasitism and intensity of inflammation suggests, along with the presence of autoreactive immune responses, that CChC results from the action of an autoimmune response. Herein we review reports from the literature and our own data, which together indicate, on one hand, the participation of parasite-specific immune responses and, on the other hand, clearly demonstrate the participation of heart-specific immune responses in the pathogenesis of CChC. Moreover, multiple factors may determine whether an individual in the indeterminate form of the disease will develop CChC. The mechanisms by which T. cruzi breaks immunological tolerance to heart antigens are also discussed.A doença de Chagas constitui um grave problema de saúde pública na América Latina, onde é uma das principais causas de problemas cardíacos. A cardiopatia chagásica crônica (CChC, forma mais grave da doença, manifesta-se em cerca de 25% dos indivíduos infectados pelo Trypanosoma cruzi, e é caracterizada, a nível histopatológico, pela presença de infiltrados

  19. Parasites of importance for human health in Nigerian dogs: high prevalence and limited knowledge of pet owners.

    Science.gov (United States)

    Ugbomoiko, Uade Samuel; Ariza, Liana; Heukelbach, Jorg

    2008-12-09

    Dogs are the most common pet animals worldwide. They may harbour a wide range of parasites with zoonotic potential, thus causing a health risk to humans. In Nigeria, epidemiological knowledge on these parasites is limited. In a community-based study, we examined 396 dogs in urban and rural areas of Ilorin (Kwara State, Central Nigeria) for ectoparasites and intestinal helminths. In addition, a questionnaire regarding knowledge and practices was applied to pet owners. Nine ectoparasite species belonging to four taxa and six intestinal helminth species were identified: fleas (Ctenocephalides canis, Pulex irritans, Tunga penetrans), mites (Demodex canis, Otodectes sp., Sarcoptes scabiei var. canis), ticks (Rhipicephalus sanguineus, Ixodes sp.), and lice (Trichodectes canis); and Toxocara canis, Ancylostoma sp., Trichuris vulpis, Dipylidium caninum, Taenidae and Strongyloides sp. Overall prevalence of ectoparasites was 60.4% and of intestinal helminths 68.4%. The occurrence of C. canis, R. sanguineus, T. canis, Ancylostoma sp. and T. vulpis was most common (prevalence 14.4% to 41.7%). Prevalence patterns in helminths were age-dependent, with T. canis showing a decreasing prevalence with age of host, and a reverse trend in other parasite species. Knowledge regarding zoonoses was very limited and the diseases not considered a major health problem. Treatment with antiparasitic drugs was more frequent in urban areas. Parasites of importance for human health were highly prevalent in Nigerian dogs. Interventions should include health education provided to dog owners and the establishment of a program focusing on zoonotic diseases.

  20. Application of nuclear techniques in study of host parasite relationship and immunological control of parasite diseases of livestock in India- an overview

    International Nuclear Information System (INIS)

    Sharma, R.L.

    1996-01-01

    The objective of this review article was to make a realistic appraisal of scientific achievements in understanding host parasite relationship and in development of safe effective diagnosis of diseases caused by parasites. The article also enlists future prospects and areas of future study. 99 refs., 4 tabs

  1. The Functioning of Strategic Management in the Control of Endemic Parasitic Diseases in Iran (Case: fascioliasis

    Directory of Open Access Journals (Sweden)

    Bahador Hajimohammadi

    2018-03-01

    Full Text Available Strategic management in the control of endemic parasitic diseases is essential according to their widespread negative consequences. Fascioliasis is one of the most common diseases of this kind in Iran. Preventing and controlling of this disease requires the formulation of a suitable strategic plan with rational goals and main strategies as same as the development, implementing and monitoring of operational programs.

  2. Humanized mouse models: Application to human diseases.

    Science.gov (United States)

    Ito, Ryoji; Takahashi, Takeshi; Ito, Mamoru

    2018-05-01

    Humanized mice are superior to rodents for preclinical evaluation of the efficacy and safety of drug candidates using human cells or tissues. During the past decade, humanized mouse technology has been greatly advanced by the establishment of novel platforms of genetically modified immunodeficient mice. Several human diseases can be recapitulated using humanized mice due to the improved engraftment and differentiation capacity of human cells or tissues. In this review, we discuss current advanced humanized mouse models that recapitulate human diseases including cancer, allergy, and graft-versus-host disease. © 2017 Wiley Periodicals, Inc.

  3. New vaccines for neglected parasitic diseases and dengue.

    Science.gov (United States)

    Beaumier, Coreen M; Gillespie, Portia M; Hotez, Peter J; Bottazzi, Maria Elena

    2013-09-01

    Neglected tropical diseases (NTDs) are a significant source of morbidity and socioeconomic burden among the world's poor. Virtually all of the 2.4 billion people who live on less than $2 per d, more than a third of the world's population, are at risk for these debilitating NTDs. Although chemotherapeutic measures exist for many of these pathogens, they are not sustainable countermeasures on their own because of rates of reinfection, risk of drug resistance, and inconsistent maintenance of drug treatment programs. Preventative and therapeutic NTD vaccines are needed as long-term solutions. Because there is no market in the for-profit sector of vaccine development for these pathogens, much of the effort to develop vaccines is driven by nonprofit entities, mostly through product development partnerships. This review describes the progress of vaccines under development for many of the NTDs, with a specific focus on those about to enter or that are currently in human clinical trials. Specifically, we report on the progress on dengue, hookworm, leishmaniasis, schistosomiasis, Chagas disease, and onchocerciasis vaccines. These products will be some of the first with specific objectives to aid the world's poorest populations. Copyright © 2013 Mosby, Inc. All rights reserved.

  4. Proteolytic activity in the adult and larval stages of the human roundworm parasite Angiostrongylus costaricensis

    Directory of Open Access Journals (Sweden)

    Karina Mastropasqua Rebello

    2012-09-01

    Full Text Available Angiostrongylus costaricensis is a nematode that causes abdominal angiostrongyliasis, a widespread human parasitism in Latin America. This study aimed to characterize the protease profiles of different developmental stages of this helminth. First-stage larvae (L1 were obtained from the faeces of infected Sigmodon hispidus rodents and third-stage larvae (L3 were collected from mollusks Biomphalaria glabrata previously infected with L1. Adult worms were recovered from rodent mesenteric arteries. Protein extraction was performed after repeated freeze-thaw cycles followed by maceration of the nematodes in 40 mM Tris base. Proteolysis of gelatin was observed by zymography and found only in the larval stages. In L3, the gelatinolytic activity was effectively inhibited by orthophenanthroline, indicating the involvement of metalloproteases. The mechanistic class of the gelatinases from L1 could not be precisely determined using traditional class-specific inhibitors. Adult worm extracts were able to hydrolyze haemoglobin in solution, although no activity was observed by zymography. This haemoglobinolytic activity was ascribed to aspartic proteases following its effective inhibition by pepstatin, which also inhibited the haemoglobinolytic activity of L1 and L3 extracts. The characterization of protease expression throughout the A. costaricensis life cycle may reveal key factors influencing the process of parasitic infection and thus foster our understanding of the disease pathogenesis.

  5. Food plant derived disease tolerance and resistance in a natural butterfly-plant-parasite interactions.

    Science.gov (United States)

    Sternberg, Eleanore D; Lefèvre, Thierry; Li, James; de Castillejo, Carlos Lopez Fernandez; Li, Hui; Hunter, Mark D; de Roode, Jacobus C

    2012-11-01

    Organisms can protect themselves against parasite-induced fitness costs through resistance or tolerance. Resistance includes mechanisms that prevent infection or limit parasite growth while tolerance alleviates the fitness costs from parasitism without limiting infection. Although tolerance and resistance affect host-parasite coevolution in fundamentally different ways, tolerance has often been ignored in animal-parasite systems. Where it has been studied, tolerance has been assumed to be a genetic mechanism, unaffected by the host environment. Here we studied the effects of host ecology on tolerance and resistance to infection by rearing monarch butterflies on 12 different species of milkweed food plants and infecting them with a naturally occurring protozoan parasite. Our results show that monarch butterflies experience different levels of tolerance to parasitism depending on the species of milkweed that they feed on, with some species providing over twofold greater tolerance than other milkweed species. Resistance was also affected by milkweed species, but there was no relationship between milkweed-conferred resistance and tolerance. Chemical analysis suggests that infected monarchs obtain highest fitness when reared on milkweeds with an intermediate concentration, diversity, and polarity of toxic secondary plant chemicals known as cardenolides. Our results demonstrate that environmental factors-such as interacting species in ecological food webs-are important drivers of disease tolerance. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

  6. Visceral leishmaniasis in eastern Sudan: parasite identification in humans and dogs; host-parasite relationships.

    Science.gov (United States)

    Dereure, Jacques; El-Safi, Sayda Hassan; Bucheton, Bruno; Boni, Mickaël; Kheir, Musa Mohamed; Davoust, Bernard; Pratlong, Francine; Feugier, Eric; Lambert, Monique; Dessein, Alain; Dedet, Jean Pierre

    2003-10-01

    In 1996, an epidemic outbreak of visceral leishmaniasis (VL) started in Barbar el Fugara, a village in Gedarif State (eastern Sudan). From 1997 to 2000, regular epidemiological studies were carried out in the human population, as well as in mammals and sand flies. In symptomatic patients, 46/69 lymph node, 6/20 post kala-azar dermal leishmaniasis (PKDL) and 1/4 cutaneous cultures in NNN medium were positive. In 69 dogs, 23/79 lymph node cultures were positive. In other mammals (47 rodents, five donkeys, one mongoose and one monkey) spleen and/or blood cultures were negative. Characterization of isolated strains (by starch gel electrophoresis and isoelectrofocusing) identified three zymodemes of Leishmania donovani, two of L. infantum and two of L. archibaldi complexes from patient samples and three zymodemes of L. donovani, three of L. infantum and two of L. archibaldi complexes from dog samples. Five of them were present in both man and dog. For the first time, a strain from a PKDL case was identified as L. infantum, and a child had the same L. infantum zymodeme in VL and in subsequent PKDL. Blood samples from dogs were studied by immunofluorescent antibody test (IFAT). The seroprevalence in dogs was 72.5%, 74.3% and 42.9% in 1998, 1999 and 2000, respectively. By using CDC miniature light traps 12 745 sand flies were collected and then identified. Phlebotomus papatasi (7%) and P. orientalis (5%) were sympatric, mainly inside homes (85% and 75%, respectively). These results, the relative stability of seroprevalence in dogs and the intradomiciliar presence of P. orientalis, known as a vector of VL in Sudan, suggest several hypotheses: (i) man is responsible for the disease in dogs, (ii) the dog is the reservoir of VL, (iii) the dog is an intermediate host between a possible sylvatic cycle and the anthroponotic cycle. More extensive studies are needed to assess the transmission cycle of VL in this area of Sudan.

  7. Genome sequencing of chimpanzee malaria parasites reveals possible pathways of adaptation to human hosts

    KAUST Repository

    Otto, Thomas D.

    2014-09-09

    Plasmodium falciparum causes most human malaria deaths, having prehistorically evolved from parasites of African Great Apes. Here we explore the genomic basis of P. falciparum adaptation to human hosts by fully sequencing the genome of the closely related chimpanzee parasite species P. reichenowi, and obtaining partial sequence data from a more distantly related chimpanzee parasite (P. gaboni). The close relationship between P. reichenowi and P. falciparum is emphasized by almost complete conservation of genomic synteny, but against this strikingly conserved background we observe major differences at loci involved in erythrocyte invasion. The organization of most virulence-associated multigene families, including the hypervariable var genes, is broadly conserved, but P. falciparum has a smaller subset of rif and stevor genes whose products are expressed on the infected erythrocyte surface. Genome-wide analysis identifies other loci under recent positive selection, but a limited number of changes at the host–parasite interface may have mediated host switching.

  8. The genome of the simian and human malaria parasite Plasmodium knowlesi

    DEFF Research Database (Denmark)

    Pain, A; Böhme, U; Berry, A E

    2008-01-01

    Plasmodium knowlesi is an intracellular malaria parasite whose natural vertebrate host is Macaca fascicularis (the 'kra' monkey); however, it is now increasingly recognized as a significant cause of human malaria, particularly in southeast Asia. Plasmodium knowlesi was the first malaria parasite...... species in which antigenic variation was demonstrated, and it has a close phylogenetic relationship to Plasmodium vivax, the second most important species of human malaria parasite (reviewed in ref. 4). Despite their relatedness, there are important phenotypic differences between them, such as host blood...... cell preference, absence of a dormant liver stage or 'hypnozoite' in P. knowlesi, and length of the asexual cycle (reviewed in ref. 4). Here we present an analysis of the P. knowlesi (H strain, Pk1(A+) clone) nuclear genome sequence. This is the first monkey malaria parasite genome to be described...

  9. Human drivers of ecological and evolutionary dynamics in emerging and disappearing infectious disease systems.

    Science.gov (United States)

    Rogalski, Mary A; Gowler, Camden D; Shaw, Clara L; Hufbauer, Ruth A; Duffy, Meghan A

    2017-01-19

    Humans have contributed to the increased frequency and severity of emerging infectious diseases, which pose a significant threat to wild and domestic species, as well as human health. This review examines major pathways by which humans influence parasitism by altering (co)evolutionary interactions between hosts and parasites on ecological timescales. There is still much to learn about these interactions, but a few well-studied cases show that humans influence disease emergence every step of the way. Human actions significantly increase dispersal of host, parasite and vector species, enabling greater frequency of infection in naive host populations and host switches. Very dense host populations resulting from urbanization and agriculture can drive the evolution of more virulent parasites and, in some cases, more resistant host populations. Human activities that reduce host genetic diversity or impose abiotic stress can impair the ability of hosts to adapt to disease threats. Further, evolutionary responses of hosts and parasites can thwart disease management and biocontrol efforts. Finally, in rare cases, humans influence evolution by eradicating an infectious disease. If we hope to fully understand the factors driving disease emergence and potentially control these epidemics we must consider the widespread influence of humans on host and parasite evolutionary trajectories.This article is part of the themed issue 'Human influences on evolution, and the ecological and societal consequences'. © 2016 The Author(s).

  10. Molecular characterisation of protist parasites in human-habituated mountain gorillas (Gorilla beringei beringei), humans and livestock, from Bwindi impenetrable National Park, Uganda.

    Science.gov (United States)

    Nolan, Matthew J; Unger, Melisa; Yeap, Yuen-Ting; Rogers, Emma; Millet, Ilary; Harman, Kimberley; Fox, Mark; Kalema-Zikusoka, Gladys; Blake, Damer P

    2017-07-18

    Over 60 % of human emerging infectious diseases are zoonotic, and there is growing evidence of the zooanthroponotic transmission of diseases from humans to livestock and wildlife species, with major implications for public health, economics, and conservation. Zooanthroponoses are of relevance to critically endangered species; amongst these is the mountain gorilla (Gorilla beringei beringei) of Uganda. Here, we assess the occurrence of Cryptosporidium, Cyclospora, Giardia, and Entamoeba infecting mountain gorillas in the Bwindi Impenetrable National Park (BINP), Uganda, using molecular methods. We also assess the occurrence of these parasites in humans and livestock species living in overlapping/adjacent geographical regions. Diagnostic PCR detected Cryptosporidium parvum in one sample from a mountain gorilla (IIdA23G2) and one from a goat (based on SSU). Cryptosporidium was not detected in humans or cattle. Cyclospora was not detected in any of the samples analysed. Giardia was identified in three human and two cattle samples, which were linked to assemblage A, B and E of G. duodenalis. Sequences defined as belonging to the genus Entamoeba were identified in all host groups. Of the 86 sequence types characterised, one, seven and two have been recorded previously to represent genotypes of Cryptosporidium, Giardia, and Entamoeba, respectively, from humans, other mammals, and water sources globally. This study provides a snapshot of the occurrence and genetic make-up of selected protists in mammals in and around BINP. The genetic analyses indicated that 54.6% of the 203 samples analysed contained parasites that matched species, genotypes, or genetic assemblages found globally. Seventy-six new sequence records were identified here for the first time. As nothing is known about the zoonotic/zooanthroponotic potential of the corresponding parasites, future work should focus on wider epidemiological investigations together with continued surveillance of all parasites in

  11. Amplicon-Based Pyrosequencing Reveals High Diversity of Protistan Parasites in Ships' Ballast Water: Implications for Biogeography and Infectious Diseases.

    Science.gov (United States)

    Pagenkopp Lohan, K M; Fleischer, R C; Carney, K J; Holzer, K K; Ruiz, G M

    2016-04-01

    Ships' ballast water (BW) commonly moves macroorganisms and microorganisms across the world's oceans and along coasts; however, the majority of these microbial transfers have gone undetected. We applied high-throughput sequencing methods to identify microbial eukaryotes, specifically emphasizing the protistan parasites, in ships' BW collected from vessels calling to the Chesapeake Bay (Virginia and Maryland, USA) from European and Eastern Canadian ports. We utilized tagged-amplicon 454 pyrosequencing with two general primer sets, amplifying either the V4 or V9 domain of the small subunit (SSU) of the ribosomal RNA (rRNA) gene complex, from total DNA extracted from water samples collected from the ballast tanks of bulk cargo vessels. We detected a diverse group of protistan taxa, with some known to contain important parasites in marine systems, including Apicomplexa (unidentified apicomplexans, unidentified gregarines, Cryptosporidium spp.), Dinophyta (Blastodinium spp., Euduboscquella sp., unidentified syndinids, Karlodinium spp., Syndinium spp.), Perkinsea (Parvilucifera sp.), Opisthokonta (Ichthyosporea sp., Pseudoperkinsidae, unidentified ichthyosporeans), and Stramenopiles (Labyrinthulomycetes). Further characterization of groups with parasitic taxa, consisting of phylogenetic analyses for four taxa (Cryptosporidium spp., Parvilucifera spp., Labyrinthulomycetes, and Ichthyosporea), revealed that sequences were obtained from both known and novel lineages. This study demonstrates that high-throughput sequencing is a viable and sensitive method for detecting parasitic protists when present and transported in the ballast water of ships. These data also underscore the potential importance of human-aided dispersal in the biogeography of these microbes and emerging diseases in the world's oceans.

  12. Global biogeography of human infectious diseases.

    Science.gov (United States)

    Murray, Kris A; Preston, Nicholas; Allen, Toph; Zambrana-Torrelio, Carlos; Hosseini, Parviez R; Daszak, Peter

    2015-10-13

    The distributions of most infectious agents causing disease in humans are poorly resolved or unknown. However, poorly known and unknown agents contribute to the global burden of disease and will underlie many future disease risks. Existing patterns of infectious disease co-occurrence could thus play a critical role in resolving or anticipating current and future disease threats. We analyzed the global occurrence patterns of 187 human infectious diseases across 225 countries and seven epidemiological classes (human-specific, zoonotic, vector-borne, non-vector-borne, bacterial, viral, and parasitic) to show that human infectious diseases exhibit distinct spatial grouping patterns at a global scale. We demonstrate, using outbreaks of Ebola virus as a test case, that this spatial structuring provides an untapped source of prior information that could be used to tighten the focus of a range of health-related research and management activities at early stages or in data-poor settings, including disease surveillance, outbreak responses, or optimizing pathogen discovery. In examining the correlates of these spatial patterns, among a range of geographic, epidemiological, environmental, and social factors, mammalian biodiversity was the strongest predictor of infectious disease co-occurrence overall and for six of the seven disease classes examined, giving rise to a striking congruence between global pathogeographic and "Wallacean" zoogeographic patterns. This clear biogeographic signal suggests that infectious disease assemblages remain fundamentally constrained in their distributions by ecological barriers to dispersal or establishment, despite the homogenizing forces of globalization. Pathogeography thus provides an overarching context in which other factors promoting infectious disease emergence and spread are set.

  13. Normocyte-binding protein required for human erythrocyte invasion by the zoonotic malaria parasitePlasmodium knowlesi

    KAUST Repository

    Moon, Robert W.; Sharaf, Hazem; Hastings, Claire H.; Ho, Yung Shwen; Nair, Mridul; Rchiad, ‍ Zineb; Knuepfer, Ellen; Ramaprasad, Abhinay; Mohring, Franziska; Amir, Amirah; Yusuf, Noor A.; Hall, Joanna; Almond, Neil; Lau, Yee Ling; Pain, Arnab; Blackman, Michael J.; Holder, Anthony A.

    2016-01-01

    The dominant cause of malaria in Malaysia is now Plasmodium knowlesi, a zoonotic parasite of cynomolgus macaque monkeys found throughout South East Asia. Comparative genomic analysis of parasites adapted to in vitro growth in either cynomolgus or human RBCs identified a genomic deletion that includes the gene encoding normocyte-binding protein Xa (NBPXa) in parasites growing in cynomolgus RBCs but not in human RBCs. Experimental deletion of the NBPXa gene in parasites adapted to growth in human RBCs (which retain the ability to grow in cynomolgus RBCs) restricted them to cynomolgus RBCs, demonstrating that this gene is selectively required for parasite multiplication and growth in human RBCs. NBPXa-null parasites could bind to human RBCs, but invasion of these cells was severely impaired. Therefore, NBPXa is identified as a key mediator of P. knowlesi human infection and may be a target for vaccine development against this emerging pathogen.

  14. Normocyte-binding protein required for human erythrocyte invasion by the zoonotic malaria parasitePlasmodium knowlesi

    KAUST Repository

    Moon, Robert W.

    2016-06-15

    The dominant cause of malaria in Malaysia is now Plasmodium knowlesi, a zoonotic parasite of cynomolgus macaque monkeys found throughout South East Asia. Comparative genomic analysis of parasites adapted to in vitro growth in either cynomolgus or human RBCs identified a genomic deletion that includes the gene encoding normocyte-binding protein Xa (NBPXa) in parasites growing in cynomolgus RBCs but not in human RBCs. Experimental deletion of the NBPXa gene in parasites adapted to growth in human RBCs (which retain the ability to grow in cynomolgus RBCs) restricted them to cynomolgus RBCs, demonstrating that this gene is selectively required for parasite multiplication and growth in human RBCs. NBPXa-null parasites could bind to human RBCs, but invasion of these cells was severely impaired. Therefore, NBPXa is identified as a key mediator of P. knowlesi human infection and may be a target for vaccine development against this emerging pathogen.

  15. Human intestinal parasites in the past: new findings and a review

    Directory of Open Access Journals (Sweden)

    Marcelo Luiz Carvalho Gonçalves

    2003-01-01

    Full Text Available Almost all known human specific parasites have been found in ancient feces. A review of the paleoparasitological helminth and intestinal protozoa findings available in the literature is presented. We also report the new paleoparasitologic findings from the examination performed in samples collected in New and Old World archaeological sites. New finds of ancylostomid, Ascaris lumbricoides, Trichuris trichiura, Enterobius vermicularis, Trichostrongylus spp., Diphyllobothrium latum, Hymenolepis nana and Acantocephalan eggs are reported. According to the findings, it is probable that A. lumbricoides was originally a human parasite. Human ancylostomids, A. lumbricoides and T. trichiura, found in the New World in pre-Columbian times, have not been introduced into the Americas by land via Beringia. These parasites could not supported the cold climate of the region. Nomadic prehistoric humans that have crossed the Bering Land Bridge from Asia to the Americas in the last glaciation, probably during generations, would have lost these parasites, which life cycles need warm temperatures in the soil to be transmitted from host to host. Alternative routes are discussed for human parasite introduction into the Americas.

  16. Linking Microbiota to Human Diseases

    DEFF Research Database (Denmark)

    Wu, Hao; Tremaroli, Valentina; Bäckhed, F

    2015-01-01

    The human gut microbiota encompasses a densely populated ecosystem that provides essential functions for host development, immune maturation, and metabolism. Alterations to the gut microbiota have been observed in numerous diseases, including human metabolic diseases such as obesity, type 2...

  17. Membrane-Wrapping Contributions to Malaria Parasite Invasion of the Human Erythrocyte

    Science.gov (United States)

    Dasgupta, Sabyasachi; Auth, Thorsten; Gov, Nir S.; Satchwell, Timothy J.; Hanssen, Eric; Zuccala, Elizabeth S.; Riglar, David T.; Toye, Ashley M.; Betz, Timo; Baum, Jake; Gompper, Gerhard

    2014-01-01

    The blood stage malaria parasite, the merozoite, has a small window of opportunity during which it must successfully target and invade a human erythrocyte. The process of invasion is nonetheless remarkably rapid. To date, mechanistic models of invasion have focused predominantly on the parasite actomyosin motor contribution to the energetics of entry. Here, we have conducted a numerical analysis using dimensions for an archetypal merozoite to predict the respective contributions of the host-parasite interactions to invasion, in particular the role of membrane wrapping. Our theoretical modeling demonstrates that erythrocyte membrane wrapping alone, as a function of merozoite adhesive and shape properties, is sufficient to entirely account for the first key step of the invasion process, that of merozoite reorientation to its apex and tight adhesive linkage between the two cells. Next, parasite-induced reorganization of the erythrocyte cytoskeleton and release of parasite-derived membrane can also account for a considerable energetic portion of actual invasion itself, through membrane wrapping. Thus, contrary to the prevailing dogma, wrapping by the erythrocyte combined with parasite-derived membrane release can markedly reduce the expected contributions of the merozoite actomyosin motor to invasion. We therefore propose that invasion is a balance between parasite and host cell contributions, evolved toward maximal efficient use of biophysical forces between the two cells. PMID:24988340

  18. in Human Liver Diseases

    Directory of Open Access Journals (Sweden)

    Minoru Fujimoto

    2010-01-01

    Full Text Available Toll-like receptor (TLR signaling pathways are strictly coordinated by several mechanisms to regulate adequate innate immune responses. Recent lines of evidence indicate that the suppressor of cytokine signaling (SOCS family proteins, originally identified as negative-feedback regulators in cytokine signaling, are involved in the regulation of TLR-mediated immune responses. SOCS1, a member of SOCS family, is strongly induced upon TLR stimulation. Cells lacking SOCS1 are hyperresponsive to TLR stimulation. Thus, SOCS1 is an important regulator for both cytokine and TLR-induced responses. As an immune organ, the liver contains various types of immune cells such as T cells, NK cells, NKT cells, and Kupffer cells and is continuously challenged with gut-derived bacterial and dietary antigens. SOCS1 may be implicated in pathophysiology of the liver. The studies using SOCS1-deficient mice revealed that endogenous SOCS1 is critical for the prevention of liver diseases such as hepatitis, cirrhosis, and cancers. Recent studies on humans suggest that SOCS1 is involved in the development of various liver disorders in humans. Thus, SOCS1 and other SOCS proteins are potential targets for the therapy of human liver diseases.

  19. Survey of diseases and parasites of honeybees (Apis mellifera L.) in Sudan

    International Nuclear Information System (INIS)

    El-Niweiri, M. A.; El-Sarrag, M. S. A.; Satti, A. A.

    2009-01-01

    A survey of the honeybee diseases and parasites including questionnaires were carried out in eight bee areas in Sudan during the season 2002/03. About 117 local colonies and 324 packages of imported colonies of Apis mellifera were inspected, in addition to 25 colonies of Apis florea. All areas were found to be free of most bacterial brood diseases and fungal diseases, except the bacterial brood disease (Serratia marcescens) which was merely detected in 2.6% of Khartoum colonies. However, non infective dysentery was the only adult disease found during this study infecting 18.2% of Kordofan colonies. On the other hand, the parasitic mite (Varroa jacobsoni) was reported as first record in Sudan, detected only in Khartoum State infecting about 75% of colonies in apiaries and 27% of wild colonies. Sudanese honeybees were found to be characterized by hygienic behaviour of colonies which resist most pests and diseases, and no chemicals were used for control.(Author)

  20. A systematic review of zoonotic enteric parasitic diseases among nomadic and pastoral people.

    Directory of Open Access Journals (Sweden)

    Amber N Barnes

    Full Text Available Zoonotic enteric parasites are ubiquitous and remain a public health threat to humans due to our close relationship with domestic animals and wildlife, inadequate water, sanitation, and hygiene practices and diet. While most communities are now sedentary, nomadic and pastoral populations still exist and experience unique exposure risks for acquiring zoonotic enteric parasites. Through this systematic review we sought to summarize published research regarding pathogens present in nomadic populations and to identify the risk factors for their infection.Using systematic review guidelines set forth by PRISMA, research articles were identified, screened and summarized based on exclusion criteria for the documented presence of zoonotic enteric parasites within nomadic or pastoral human populations. A total of 54 articles published between 1956 and 2016 were reviewed to determine the pathogens and exposure risks associated with the global transhumance lifestyle.The included articles reported more than twenty different zoonotic enteric parasite species and illustrated several risk factors for nomadic and pastoralist populations to acquire infection including; a animal contact, b food preparation and diet, and c household characteristics. The most common parasite studied was Echinococcosis spp. and contact with dogs was recognized as a leading risk factor for zoonotic enteric parasites followed by contact with livestock and/or wildlife, water, sanitation, and hygiene barriers, home slaughter of animals, environmental water exposures, household member age and sex, and consumption of unwashed produce or raw, unprocessed, or undercooked milk or meat.Nomadic and pastoral communities are at risk of infection with a variety of zoonotic enteric parasites due to their living environment, cultural and dietary traditions, and close relationship to animals. Global health efforts aimed at reducing the transmission of these animal-to-human pathogens must incorporate

  1. Pathoecology of Chiribaya parasitism

    Directory of Open Access Journals (Sweden)

    Martinson Elizabeth

    2003-01-01

    Full Text Available The excavations of Chiribaya culture sites in the Osmore drainage of southern Peru focused on the recovery of information about prehistoric disease, including parasitism. The archaeologists excavated human, dog, guinea pig, and llama mummies. These mummies were analyzed for internal and external parasites. The results of the analysis and reconstruction of prehistoric life from the excavations allows us to interpret the pathoecology of the Chiribaya culture.

  2. [Challenge and strategy of prevention and control of important parasitic diseases under the Belt and Road Initiative].

    Science.gov (United States)

    Chun-Li, Cao; Jia-Gang, Guo

    2018-04-17

    China was once a country with the heaviest burden of parasitic diseases. Under the leadership of the Communist Party and national authority, after more than 60 years' efforts of prevention and control, the remarkable results have been achieved in China. However, affected by the social and economic development and environmental changes, the prevention and control of parasitic diseases, especially imported parasitic diseases, are facing new challenges, and the parasitic diseases, such as malaria, schistosomiasis, leishmaniasis, filariasis and trypanosomiasis, appear increasingly. With the development of the Belt and Road Initiative, the transmission risks of these diseases are more increased. The purpose of this paper is to describe the experience and results of parasitic disease prevention and control in China, understand the present parasitic disease epidemic situation of the Belt and Road Initiative related countries, analyze the transmission risks of important parasitic diseases, and present some relevant suggestions, so as to provide the evidence for the health administrative department formulating the prevention and control strategies of such parasitic diseases timely and effectively.

  3. Parasites and other infectious agents in marine finfish and shellfish species posing a hazard to human health (ToR b)

    DEFF Research Database (Denmark)

    Alfjorden, A.; Podolska, M.; Karaseva, T.

    2015-01-01

    Several parasites and other infectious agents frequently reported by the WGPDMO in the annual update of disease trends (ICES WGPDMO reports 1999–2015) have the potential to be harmful to human health if ingested in unprocessed or inadequate-ly/partly processed seafood. These include, but are not ...

  4. Human parasitic meningitis caused by Angiostrongylus cantonensis infection in Taiwan.

    Science.gov (United States)

    Tsai, Hung-Chin; Chen, Yao-Shen; Yen, Chuan-Min

    2013-06-01

    The major cause of eosinophilic meningitis in Taiwan is Angiostrongylus cantonensis. Humans are infected by ingesting terrestrial and freshwater snails and slugs. In 1998 and 1999, two outbreaks of eosinophilic meningitis caused by A. cantonensis infection were reported among 17 adult male immigrant Thai laborers who had eaten raw golden apple snails (Pomacea canaliculata). Another outbreak associated with consuming a health drink consisting of raw vegetable juice was reported in 2001. These adult cases differed from reports in the 1970s and 1980s, in which most of the cases were in children. With improvements in public health and education of foreign laborers, there have since been only sporadic cases in Taiwan. Review of clinical research indicates inconsistent association of Magnetic Resonance Imaging (MRI) results with clinical features of eosinophilic meningitis. MRI features were nonspecific but there was an association between the presence of high brain MRI signal intensities and severity of peripheral and cerebrospinal fluid (CSF) eosinophilia. Inflammatory markers have been identified in the CSF of patients with eosinophilic meningitis caused by A. cantonensis infection, and vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), and the matrix metalloproteinase system may be associated with blood-brain barrier disruption. Eosinophilic meningitis caused by A. cantonensis infection is not a reportable disease in Taiwan. It is important that a public advisory and education program be developed to reduce future accidental infection.

  5. A review of sexually transmitted diseases (STDs) of parasitic origin ...

    African Journals Online (AJOL)

    fore a now recognized mode of transmission – sexual contact. This in turn has led to giardiasis being classified as a sexually transmitted disease by the Centre for Disease Control and Prevention (CDC) in the United States. This review identifies its occurrence mainly in homosexual populations of the developed world ...

  6. [SWOT analysis of laboratory certification and accreditation on detection of parasitic diseases].

    Science.gov (United States)

    Xiong, Yan-hong; Zheng, Bin

    2014-04-01

    This study analyzes the strength, weakness, opportunity and threat (SWOT) of laboratory certification and accreditation on detection of parasitic diseases by SWOT analysis comprehensively, and it puts forward some development strategies specifically, in order to provide some indicative references for the further development.

  7. Genetic recombination between human and animal parasites creates novel strains of human pathogen.

    Directory of Open Access Journals (Sweden)

    Wendy Gibson

    2015-03-01

    Full Text Available Genetic recombination between pathogens derived from humans and livestock has the potential to create novel pathogen strains, highlighted by the influenza pandemic H1N1/09, which was derived from a re-assortment of swine, avian and human influenza A viruses. Here we investigated whether genetic recombination between subspecies of the protozoan parasite, Trypanosoma brucei, from humans and animals can generate new strains of human pathogen, T. b. rhodesiense (Tbr responsible for sleeping sickness (Human African Trypanosomiasis, HAT in East Africa. The trait of human infectivity in Tbr is conferred by a single gene, SRA, which is potentially transferable to the animal pathogen Tbb by sexual reproduction. We tracked the inheritance of SRA in crosses of Tbr and Tbb set up by co-transmitting genetically-engineered fluorescent parental trypanosome lines through tsetse flies. SRA was readily transferred into new genetic backgrounds by sexual reproduction between Tbr and Tbb, thus creating new strains of the human pathogen, Tbr. There was no evidence of diminished growth or transmissibility of hybrid trypanosomes carrying SRA. Although expression of SRA is critical to survival of Tbr in the human host, we show that the gene exists as a single copy in a representative collection of Tbr strains. SRA was found on one homologue of chromosome IV in the majority of Tbr isolates examined, but some Ugandan Tbr had SRA on both homologues. The mobility of SRA by genetic recombination readily explains the observed genetic variability of Tbr in East Africa. We conclude that new strains of the human pathogen Tbr are being generated continuously by recombination with the much larger pool of animal-infective trypanosomes. Such novel recombinants present a risk for future outbreaks of HAT.

  8. Genetic recombination between human and animal parasites creates novel strains of human pathogen.

    Science.gov (United States)

    Gibson, Wendy; Peacock, Lori; Ferris, Vanessa; Fischer, Katrin; Livingstone, Jennifer; Thomas, James; Bailey, Mick

    2015-03-01

    Genetic recombination between pathogens derived from humans and livestock has the potential to create novel pathogen strains, highlighted by the influenza pandemic H1N1/09, which was derived from a re-assortment of swine, avian and human influenza A viruses. Here we investigated whether genetic recombination between subspecies of the protozoan parasite, Trypanosoma brucei, from humans and animals can generate new strains of human pathogen, T. b. rhodesiense (Tbr) responsible for sleeping sickness (Human African Trypanosomiasis, HAT) in East Africa. The trait of human infectivity in Tbr is conferred by a single gene, SRA, which is potentially transferable to the animal pathogen Tbb by sexual reproduction. We tracked the inheritance of SRA in crosses of Tbr and Tbb set up by co-transmitting genetically-engineered fluorescent parental trypanosome lines through tsetse flies. SRA was readily transferred into new genetic backgrounds by sexual reproduction between Tbr and Tbb, thus creating new strains of the human pathogen, Tbr. There was no evidence of diminished growth or transmissibility of hybrid trypanosomes carrying SRA. Although expression of SRA is critical to survival of Tbr in the human host, we show that the gene exists as a single copy in a representative collection of Tbr strains. SRA was found on one homologue of chromosome IV in the majority of Tbr isolates examined, but some Ugandan Tbr had SRA on both homologues. The mobility of SRA by genetic recombination readily explains the observed genetic variability of Tbr in East Africa. We conclude that new strains of the human pathogen Tbr are being generated continuously by recombination with the much larger pool of animal-infective trypanosomes. Such novel recombinants present a risk for future outbreaks of HAT.

  9. Parasites of importance for human health in Nigerian dogs: high prevalence and limited knowledge of pet owners

    Directory of Open Access Journals (Sweden)

    Heukelbach Jorg

    2008-12-01

    Full Text Available Abstract Background Dogs are the most common pet animals worldwide. They may harbour a wide range of parasites with zoonotic potential, thus causing a health risk to humans. In Nigeria, epidemiological knowledge on these parasites is limited. Methods In a community-based study, we examined 396 dogs in urban and rural areas of Ilorin (Kwara State, Central Nigeria for ectoparasites and intestinal helminths. In addition, a questionnaire regarding knowledge and practices was applied to pet owners. Results Nine ectoparasite species belonging to four taxa and six intestinal helminth species were identified: fleas (Ctenocephalides canis, Pulex irritans, Tunga penetrans, mites (Demodex canis, Otodectes sp., Sarcoptes scabiei var. canis, ticks (Rhipicephalus sanguineus, Ixodes sp., and lice (Trichodectes canis; and Toxocara canis, Ancylostoma sp., Trichuris vulpis, Dipylidium caninum, Taenidae and Strongyloides sp. Overall prevalence of ectoparasites was 60.4% and of intestinal helminths 68.4%. The occurrence of C. canis, R. sanguineus, T. canis, Ancylostoma sp. and T. vulpis was most common (prevalence 14.4% to 41.7%. Prevalence patterns in helminths were age-dependent, with T. canis showing a decreasing prevalence with age of host, and a reverse trend in other parasite species. Knowledge regarding zoonoses was very limited and the diseases not considered a major health problem. Treatment with antiparasitic drugs was more frequent in urban areas. Conclusion Parasites of importance for human health were highly prevalent in Nigerian dogs. Interventions should include health education provided to dog owners and the establishment of a program focusing on zoonotic diseases.

  10. Analysis of a summary network of co-infection in humans reveals that parasites interact most via shared resources

    OpenAIRE

    Griffiths, Emily C; Pedersen, Amy B; Fenton, Andy; Petchey, Owen L

    2014-01-01

    Simultaneous infection by multiple parasite species (viruses, bacteria, helminths, protozoa or fungi) is commonplace. Most reports show co-infected humans to have worse health than those with single infections. However, we have little understanding of how co-infecting parasites interact within human hosts. We used data from over 300 published studies to construct a network that offers the first broad indications of how groups of co-infecting parasites tend to interact. The network had three l...

  11. A review of sexually transmitted diseases (STDs) of parasitic origin ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-12-29

    Dec 29, 2008 ... damage, cancer, heart disease, infertility and other ab- normalities of the reproductive system, ... TRANSMISSION OF GIARDIASIS THROUGH SEX. Established and more ... through the faeco-anal-oral route and transmission.

  12. Human waterborne parasites in zebra mussels ( Dreissena polymorpha) from the Shannon River drainage area, Ireland.

    Science.gov (United States)

    Graczyk, Thaddeus K; Conn, David Bruce; Lucy, Frances; Minchin, Dan; Tamang, Leena; Moura, Lacy N S; DaSilva, Alexandre J

    2004-08-01

    Zebra mussels ( Dreissena polymorpha) from throughout the Shannon River drainage area in Ireland were tested for the anthropozoonotic waterborne parasites Cryptosporidium parvum, Giardia lamblia, Encephalitozoon intestinalis, E. hellem, and Enterocytozoon bieneusi, by the multiplexed combined direct immunofluorescent antibody and fluorescent in situ hybridization method, and PCR. Parasite transmission stages were found at 75% of sites, with the highest mean concentration of 16, nine, and eight C. parvum oocysts, G. lamblia cysts, and Encephalitozoon intestinalis spores/mussel, respectively. On average eight Enterocytozoon bieneusi spores/mussel were recovered at any selected site. Approximately 80% of all parasites were viable and thus capable of initiating human infection. The Shannon River is polluted with serious emerging human waterborne pathogens including C. parvum, against which no therapy exists. Zebra mussels can recover and concentrate environmentally derived pathogens and can be used for the sanitary assessment of water quality.

  13. Fish parasites

    DEFF Research Database (Denmark)

    This book contains 22 chapters on some of the most important parasitic diseases in wild and farmed fish. International experts give updated reviews and provide solutions to the problems......This book contains 22 chapters on some of the most important parasitic diseases in wild and farmed fish. International experts give updated reviews and provide solutions to the problems...

  14. Current progress in the development and use of artemether for chemoprophylaxis of major human schistosome parasites.

    Science.gov (United States)

    Utzinger, J; Xiao, S; Keiser, J; Chen, M; Zheng, J; Tanner, M

    2001-12-01

    Human schistosomiasis, a chronic and debilitating parasitic disease of the tropics, is ranked second after malaria in terms of public health importance. At present, there is no vaccine available, and chemotherapy is the cornerstone of schistosomiasis control. Praziquantel is the drug of choice. Oxamniquine has become difficult to obtain and metrifonate has recently been withdrawn from the market. Rapid re-infection following treatment and concern about praziquantel resistance called for the search of novel drugs for prevention and cure of schistosomiasis. Significant progress has been made with artemether, the methyl ether of dihydroartemisinin, already widely used for the treatment of malaria. The present article reviews the literature that led to the development of artemether for chemoprophylaxis in schistosomiasis, and it summarises the experiences so far obtained with its use to control schistosomiasis in different endemic settings. Topics covered include an overview of the global burden of schistosomiasis and approaches for its control; the nature and features of artemisinin and related derivatives, initially discovered as antimalarials, other bioactivities, and their recent discovery of antischistosomal properties; a historic account disclosing the antischistosomal activity of artemether; in vivo assessment of drug susceptibility of different developmental stages of schistosome parasites; artemether-induced pathology evidenced by scanning and transmission electron microscopy; the possible mechanism of action; in vivo studies with combination therapy of artemether and praziquantel; results of randomised controlled clinical trials of oral artemether for the prevention of patent infection and morbidity; and, ultimately the translation of this knowledge into public health action in different endemic settings towards a more integrated approach of schistosomiasis control.

  15. Probability of Transmission of Malaria from Mosquito to Human Is Regulated by Mosquito Parasite Density in Naïve and Vaccinated Hosts.

    Directory of Open Access Journals (Sweden)

    Thomas S Churcher

    2017-01-01

    Full Text Available Over a century since Ronald Ross discovered that malaria is caused by the bite of an infectious mosquito it is still unclear how the number of parasites injected influences disease transmission. Currently it is assumed that all mosquitoes with salivary gland sporozoites are equally infectious irrespective of the number of parasites they harbour, though this has never been rigorously tested. Here we analyse >1000 experimental infections of humans and mice and demonstrate a dose-dependency for probability of infection and the length of the host pre-patent period. Mosquitoes with a higher numbers of sporozoites in their salivary glands following blood-feeding are more likely to have caused infection (and have done so quicker than mosquitoes with fewer parasites. A similar dose response for the probability of infection was seen for humans given a pre-erythrocytic vaccine candidate targeting circumsporozoite protein (CSP, and in mice with and without transfusion of anti-CSP antibodies. These interventions prevented infection more efficiently from bites made by mosquitoes with fewer parasites. The importance of parasite number has widespread implications across malariology, ranging from our basic understanding of the parasite, how vaccines are evaluated and the way in which transmission should be measured in the field. It also provides direct evidence for why the only registered malaria vaccine RTS,S was partially effective in recent clinical trials.

  16. The prevalence and diversity of intestinal parasitic infections in humans and domestic animals in a rural Cambodian village

    DEFF Research Database (Denmark)

    Schär, Fabian; Inpankaew, Tawin; Traub, Rebecca J.

    2014-01-01

    In Cambodia, intestinal parasitic infections are prevalent in humans and particularly in children. Yet, information on potentially zoonotic parasites in animal reservoir hosts is lacking. In May 2012, faecal samples from 218 humans, 94 dogs and 76 pigs were collected from 67 households in Dong vi...

  17. Common fish diseases and parasites affecting wild and farmed ...

    African Journals Online (AJOL)

    Intensification of aquaculture production in Uganda is likely to result into disease out-breaks leading to economic losses to commercial fish farms and associated natural aquatic ecosystems. This survey assessed health profiles of selected commercial fish farms and adjacent natural aquatic ecosystemsto identify fish ...

  18. Social Parasites

    Science.gov (United States)

    Lopez, Miguel A.; Nguyen, HoangKim T.; Oberholzer, Michael; Hill, Kent L.

    2011-01-01

    Summary of recent advances Protozoan parasites cause tremendous human suffering worldwide, but strategies for therapeutic intervention are limited. Recent studies illustrate that the paradigm of microbes as social organisms can be brought to bear on questions about parasite biology, transmission and pathogenesis. This review discusses recent work demonstrating adaptation of social behaviors by parasitic protozoa that cause African sleeping sickness and malaria. The recognition of social behavior and cell-cell communication as a ubiquitous property of bacteria has transformed our view of microbiology, but protozoan parasites have not generally been considered in this context. Works discussed illustrate the potential for concepts of sociomicrobiology to provide insight into parasite biology and should stimulate new approaches for thinking about parasites and parasite-host interactions. PMID:22020108

  19. Cytometric quantification of singlet oxygen in the human malaria parasite Plasmodium falciparum

    NARCIS (Netherlands)

    Butzloff, Sabine; Groves, Matthew R; Wrenger, Carsten; Müller, Ingrid B

    The malaria parasite Plasmodium falciparum proliferates within human erythrocytes and is thereby exposed to a variety of reactive oxygen species (ROS) such as hydrogen peroxide, hydroxyl radical, superoxide anion, and highly reactive singlet oxygen ((1)O(2)). While most ROS are already well studied

  20. Survey of the parasite Toxoplasma gondii in human consumed ovine meat in Tunis City.

    Directory of Open Access Journals (Sweden)

    Sonia Boughattas

    Full Text Available Toxoplasmosis has been recognized as parasitic zoonosis with the highest human incidence. The human infection by the parasite can lead to severe clinical manifestations in congenital toxoplasmosis and immunocompromised patients. Contamination occurs mainly by foodborne ways especially consumption of raw or undercooked meat. In contrast to other foodborne infections, toxoplasmosis is a chronic infection which would make its economic and social impact much higher than even previously anticipated. Ovine meat was advanced as a major risk factor, so we investigated its parasite survey, under natural conditions. Serological MAT technique and touchdown PCR approaches were used for prevalence determination of the parasite in slaughtered sheep intended to human consumption in Tunis City. The genotyping was carried by SNPs analysis of SAG3 marker. Anti-Toxoplasma antibodies were present in 38.2% of young sheep and in 73.6% of adult sheep. Molecular detection revealed the contamination of 50% of ewes' tissue. Sequencing and SNPs analysis enabled unambiguous typing of meat isolates and revealed the presence of mixed strains as those previously identified from clinical samples in the same area. Our findings conclude that slaughtered sheep are highly infected, suggesting them as a major risk factor of Toxoplasma gondii transmission by meat consumption. Special aware should target consequently this factor when recommendations have to be established by the health care commanders.

  1. The landscape of human genes involved in the immune response to parasitic worms

    Directory of Open Access Journals (Sweden)

    Fumagalli Matteo

    2010-08-01

    Full Text Available Abstract Background More than 2 billion individuals worldwide suffer from helminth infections. The highest parasite burdens occur in children and helminth infection during pregnancy is a risk factor for preterm delivery and reduced birth weight. Therefore, helminth infections can be regarded as a strong selective pressure. Results Here we propose that candidate susceptibility genes for parasitic worm infections can be identified by searching for SNPs that display a strong correlation with the diversity of helminth species/genera transmitted in different geographic areas. By a genome-wide search we identified 3478 variants that correlate with helminth diversity. These SNPs map to 810 distinct human genes including loci involved in regulatory T cell function and in macrophage activation, as well as leukocyte integrins and co-inhibitory molecules. Analysis of functional relationships among these genes identified complex interaction networks centred around Th2 cytokines. Finally, several genes carrying candidate targets for helminth-driven selective pressure also harbour susceptibility alleles for asthma/allergy or are involved in airway hyper-responsiveness, therefore expanding the known parallelism between these conditions and parasitic infections. Conclusions Our data provide a landscape of human genes that modulate susceptibility to helminths and indicate parasitic worms as one of the major selective forces in humans.

  2. Reconstructing Colonization Dynamics of the Human Parasite Schistosoma mansoni following Anthropogenic Environmental Changes in Northwest Senegal

    Science.gov (United States)

    Van den Broeck, Frederik; Maes, Gregory E.; Larmuseau, Maarten H. D.; Rollinson, David; Sy, Ibrahima; Faye, Djibril; Volckaert, Filip A. M.; Polman, Katja; Huyse, Tine

    2015-01-01

    Background Anthropogenic environmental changes may lead to ecosystem destabilization and the unintentional colonization of new habitats by parasite populations. A remarkable example is the outbreak of intestinal schistosomiasis in Northwest Senegal following the construction of two dams in the ‘80s. While many studies have investigated the epidemiological, immunological and geographical patterns of Schistosoma mansoni infections in this region, little is known about its colonization history. Methodology/Principal Findings Parasites were collected at several time points after the disease outbreak and genotyped using a 420 bp fragment of the mitochondrial cytochrome c oxidase subunit 1 gene (cox1) and nine nuclear DNA microsatellite markers. Phylogeographic and population genetic analyses revealed the presence of (i) many genetically different haplotypes at the non-recombining mitochondrial marker and (ii) one homogenous S. mansoni genetic group at the recombining microsatellite markers. These results suggest that the S. mansoni population in Northwest Senegal was triggered by intraspecific hybridization (i.e. admixture) between parasites that were introduced from different regions. This would comply with the extensive immigration of infected seasonal agricultural workers from neighboring regions in Senegal, Mauritania and Mali. The spatial and temporal stability of the established S. mansoni population suggests a swift local adaptation of the parasite to the local intermediate snail host Biomphalaria pfeifferi at the onset of the epidemic. Conclusions/Significance Our results show that S. mansoni parasites are very successful in colonizing new areas without significant loss of genetic diversity. Maintaining high levels of diversity guarantees the adaptive potential of these parasites to cope with selective pressures such as drug treatment, which might complicate efforts to control the disease. PMID:26275049

  3. Congenital Chagas disease as an ecological model of interactions between Trypanosoma cruzi parasites, pregnant women, placenta and fetuses.

    Science.gov (United States)

    Carlier, Yves; Truyens, Carine

    2015-11-01

    The aim of this paper is to discuss the main ecological interactions between the parasite Trypanosoma cruzi and its hosts, the mother and the fetus, leading to the transmission and development of congenital Chagas disease. One or several infecting strains of T. cruzi (with specific features) interact with: (i) the immune system of a pregnant woman whom responses depend on genetic and environmental factors, (ii) the placenta harboring its own defenses, and, finally, (iii) the fetal immune system displaying responses also susceptible to be modulated by maternal and environmental factors, as well as his own genetic background which is different from her mother. The severity of congenital Chagas disease depends on the magnitude of such final responses. The paper is mainly based on human data, but integrates also complementary observations obtained in experimental infections. It also focuses on important gaps in our knowledge of this congenital infection, such as the role of parasite diversity vs host genetic factors, as well as that of the maternal and placental microbiomes and the microbiome acquisition by infant in the control of infection. Investigations on these topics are needed in order to improve the programs aiming to diagnose, manage and control congenital Chagas disease. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  4. [Antagonistic interactions between saprotrophic fungi and geohelminths. 2. Saprotrophic fungi in biocontrol of parasitic geohelminths of humans and animals].

    Science.gov (United States)

    Jaborowska-Jarmoluk, Magdalena; Mazurkiewicz-Zapałowicz, Kinga; Kołodziejczyk, Lidia

    2009-01-01

    The soils ecosystem plays an important role in the epidemiology of geohelminth diseases of humans and animals. Soil contamination with ova of the parasitic geohelminths represents a global public health-hazard issue. Biological agents have been thought to control the infective forms of parasites present in the soil. Biocontrol of geohelminths represents an alternative to pesticides (i.e., nematicides), which are not efficient in killing infective nematode forms and, additionally, result in the environment pollution and long-term disturbances in the soil ecosystem homeostasis. The degree of the inhibiting effect of soil saprotrophic fungi on geohelminth embryonic development varies and depends on the species. A number of fungi cause various morphological disorders in the embryos of developing parasitic nematodes, but also have an ovicidal effect. Although the nature of the antagonism between fungi and other living organisms has not been fully explained, it is certain that mycotoxins and fungal enzymes constitute its important components. Considering the studies carried out so far, the antagonistic effect of mold fungi against the infective stages of geohelminths can be fully recommended as a real control factor, especially as these saprotrophs represent a natural factor within the soil environment, that is of particular biochemical activity.

  5. Recent Advances in Human Protozoan Parasites of Gastrointestinal Tract

    Science.gov (United States)

    1987-02-01

    organism was found in 40% and 50%, respectively. The organism did not seem to be casually involved in the inflammatory periodontal * disease. Entamoeba...and lung, and in Ecuador, B. coli was found to be the cause of bloody-mucoid diarrhea and hepatic abscess . SUMMARY An attempt was made in this report

  6. Zoonotic gastrointestinal parasite burden of local dogs in Zaria, Northern Nigeria: Implications for human health

    Directory of Open Access Journals (Sweden)

    Christopher I. Ogbaje

    2015-10-01

    Full Text Available Background: Zoonotic gastrointestinal parasites of dogs are of the global problem particularly in the developing countries. Dogs are the most common pet animals worldwide and have been reported to be hosts of many intestinal parasites of zoonotic importance globally. In Nigeria, gastrointestinal helminthes of dogs is currently endemic in 20 of the 36 states. Aim: In general, dogs are the closest animals to humans and for that reason we decided to carry out a survey study to check the incidence of these parasites in dogs and to ascertain the level of environmental contamination in the study area. Materials and Methods: Fecal samples were collected from dog patients presented to small animal clinic of Veterinary Teaching Hospital of Faculty of Veterinary Medicine, Ahmadu Bello University Zaria, dog’s fecal droppings from the streets, and residential Quarters of the University and gastrointestinal tracts (GIT of dogs from dogs slaughtering house at Basawa Barrack, Zaria. Three methods were used in the analysis of the samples; simple flotation, sedimentation, and GIT processing methods within 48 h of collection. Results: Out of 224 samples analyzed 76(33.9% were positive of at least one of the parasites. Of the 101 samples from streets and residential quarters of ABU, Zaria, Isospora spp. 12(11.9% recorded the highest prevalence rate followed by Taenia spp. 6(5.9%, then Toxocara canis, Ancylostoma caninum, and Dipylidium caninum were 5.0%, 4.0%, and 1.0%, respectively. Isospora spp. (19.0% recorded the highest prevalence rate for the 100 samples collected from small animal clinic. Other parasites encountered were T. canis (8.0%, A. caninum (8.0% and Taenia spp. (5.0%. Parasites observed from the 23 gastrointestinal contents from “dog slaughtered houses” were T. canis (17.3%, Isospora spp.(13.1% and A. caninum (4.3. Conclusion: The study revealed that zoonotic gastrointestinal parasites of dogs are endemic in Zaria and the general public in the

  7. The Plasmodium bottleneck: malaria parasite losses in the mosquito vector

    Science.gov (United States)

    Smith, Ryan C; Vega-Rodríguez, Joel; Jacobs-Lorena, Marcelo

    2014-01-01

    Nearly one million people are killed every year by the malaria parasite Plasmodium. Although the disease-causing forms of the parasite exist only in the human blood, mosquitoes of the genus Anopheles are the obligate vector for transmission. Here, we review the parasite life cycle in the vector and highlight the human and mosquito contributions that limit malaria parasite development in the mosquito host. We address parasite killing in its mosquito host and bottlenecks in parasite numbers that might guide intervention strategies to prevent transmission. PMID:25185005

  8. The Plasmodium bottleneck: malaria parasite losses in the mosquito vector

    Directory of Open Access Journals (Sweden)

    Ryan C Smith

    2014-08-01

    Full Text Available Nearly one million people are killed every year by the malaria parasite Plasmodium. Although the disease-causing forms of the parasite exist only in the human blood, mosquitoes of the genus Anopheles are the obligate vector for transmission. Here, we review the parasite life cycle in the vector and highlight the human and mosquito contributions that limit malaria parasite development in the mosquito host. We address parasite killing in its mosquito host and bottlenecks in parasite numbers that might guide intervention strategies to prevent transmission.

  9. Current Perspectives of Telomerase Structure and Function in Eukaryotes with Emerging Views on Telomerase in Human Parasites.

    Science.gov (United States)

    Dey, Abhishek; Chakrabarti, Kausik

    2018-01-24

    Replicative capacity of a cell is strongly correlated with telomere length regulation. Aberrant lengthening or reduction in the length of telomeres can lead to health anomalies, such as cancer or premature aging. Telomerase is a master regulator for maintaining replicative potential in most eukaryotic cells. It does so by controlling telomere length at chromosome ends. Akin to cancer cells, most single-cell eukaryotic pathogens are highly proliferative and require persistent telomerase activity to maintain constant length of telomere and propagation within their host. Although telomerase is key to unlimited cellular proliferation in both cases, not much was known about the role of telomerase in human parasites (malaria, Trypanosoma , etc.) until recently. Since telomerase regulation is mediated via its own structural components, interactions with catalytic reverse transcriptase and several factors that can recruit and assemble telomerase to telomeres in a cell cycle-dependent manner, we compare and discuss here recent findings in telomerase biology in cancer, aging and parasitic diseases to give a broader perspective of telomerase function in human diseases.

  10. Epidemiology of infections with intestinal parasites and human immunodeficiency virus (HIV) among sugar-estate residents in Ethiopia

    NARCIS (Netherlands)

    Fontanet, A. L.; Sahlu, T.; Rinke de Wit, T.; Messele, T.; Masho, W.; Woldemichael, T.; Yeneneh, H.; Coutinho, R. A.

    2000-01-01

    Intestinal parasitic infections could play an important role in the progression of infection with human immunodeficiency virus (HIV), by further disturbing the immune system whilst it is already engaged in the fight against HIV. HIV and intestinal parasitic infections were investigated in 1239,

  11. Dysfunctions at human intestinal barrier by water-borne protozoan parasites: lessons from cultured human fully differentiated colon cancer cell lines.

    Science.gov (United States)

    Liévin-Le Moal, Vanessa

    2013-06-01

    Some water-borne protozoan parasites induce diseases through their membrane-associated functional structures and virulence factors that hijack the host cellular molecules and signalling pathways leading to structural and functional lesions in the intestinal barrier. In this Microreview we analyse the insights on the mechanisms of pathogenesis of Entamoeba intestinalis, Giardia and Cryptosporidium observed in the human colon carcinoma fully differentiated colon cancer cell lines, cell subpopulations and clones expressing the structural and functional characteristics of highly specialized fully differentiated epithelial cells lining the intestinal epithelium and mimicking structurally and functionally an intestinal barrier. © 2013 John Wiley & Sons Ltd.

  12. Rickettsia species in human-parasitizing ticks in Greece.

    Science.gov (United States)

    Papa, Anna; Xanthopoulou, Kyriaki; Kotriotsiou, Tzimoula; Papaioakim, Miltiadis; Sotiraki, Smaragda; Chaligiannis, Ilias; Maltezos, Efstratios

    2016-05-01

    Ticks serve as vectors and reservoirs for a variety of bacterial, viral and protozoan pathogens affecting humans and animals. Unusual increased tick aggressiveness was observed in 2008-2009 in northeastern Greece. The aim of the study was to check ticks removed from persons during 2009 for infection with Rickettsia species. A total of 159 ticks were removed from 147 persons who sought medical advice in a hospital. Tick identification was performed morphologically using taxonomic keys. DNA was extracted from each individual tick and a PCR assay targeting the rickettsial outer membrane protein A gene of Rickettsia spp. was applied. Most of the adult ticks (132/153, 86.3%) were Rhipicephalus sanguineus. Rickettsiae were detected in 23 of the 153 (15.0%) adult ticks. Five Rickettsiae species were identified: R. aeschlimannii, R. africae (n=6), R. massilae (4), R. monacensis (1), and Candidatus R. barbariae (1). To our knowledge, this is the first report of R. africae, R. monacensis, and Candidatus R. barbariae in Greece. Several Rickettsia species were identified in ticks removed from humans in Greece, including those that are prevalent in northern and southern latitudes. © The Author 2016. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Diseases and parasites of laboratory reared and wild population of banded pearl spot Etroplus suratensis (Cichlidae) in Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Rattan, P.; Parulekar, A.H.

    Banded Pearl spot Etroplus suratensis, the inhabitant of coastal backwaters and lagoons is one among the few finfish species identified for brackishwater farming. Common diseases and parasites from the wild population of Goa and from the laboratory...

  14. Infectious diseases, parasites, and biological toxins in sea ducks: Chapter 4

    Science.gov (United States)

    Hollmén, Tuula E.; Franson, J. Christian

    2015-01-01

    This chapter addresses disease agents in the broad sense, including viruses, bacteria, fungi, protozoan and helminth parasites, and biological toxins. Some of these agents are known to cause mortality in sea ducks, some are thought to be incidental findings, and the significance of others is yet poorly understood. Although the focus of the chapter is on free-living sea ducks, the study of disease in this taxonomic group has been relatively limited and examples from captive sea ducks and other wild waterfowl are used to illustrate the pathogenicity of certain diseases. Much of the early work in sea ducks consisted of anecdotal and descriptive reports of parasites, but it was soon recognized that diseases such as avian cholera, renal coccidiosis, and intestinal infections with acanthocephalans were causes of mortality in wild populations. More recently, adenoviruses, reoviruses, and the newly emergent Wellfleet Bay virus, for example, also have been linked to die-offs of sea ducks. Declining populations of animals are particularly vulnerable to the threats posed by disease and it is important that we improve our understanding of the significance of disease in sea ducks. To conclude, we offer our recommendations for future directions in this field.

  15. Viruses of parasites as actors in the parasite-host relationship: A "ménage à trois".

    Science.gov (United States)

    Gómez-Arreaza, Amaranta; Haenni, Anne-Lise; Dunia, Irene; Avilán, Luisana

    2017-02-01

    The complex parasite-host relationship involves multiple mechanisms. Moreover, parasites infected by viruses modify this relationship adding more complexity to the system that now comprises three partners. Viruses infecting parasites were described several decades ago. However, until recently little was known about the viruses involved and their impact on the resulting disease caused to the hosts. To clarify this situation, we have concentrated on parasitic diseases caused to humans and on how virus-infected parasites could alter the symptoms inflicted on the human host. It is clear that the effect caused to the human host depends on the virus and on the parasite it has infected. Consequently, the review is divided as follows: Viruses with a possible effect on the virulence of the parasite. This section reviews pertinent articles showing that infection of parasites by viruses might increase the detrimental effect of the tandem virus-parasite on the human host (hypervirulence) or decrease virulence of the parasite (hypovirulence). Parasites as vectors affecting the transmission of viruses. In some cases, the virus-infected parasite might facilitate the transfer of the virus to the human host. Parasites harboring viruses with unidentified effects on their host. In spite of recently renewed interest in parasites in connection with their viruses, there still remains a number of cases in which the effect of the virus of a given parasite on the human host remains ambiguous. The triangular relationship between the virus, the parasite and the host, and the modulation of the pathogenicity and virulence of the parasites by viruses should be taken into account in the rationale of fighting against parasites. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Prevalence of parasites in soil samples in Tehran public places ...

    African Journals Online (AJOL)

    Results of our findings provide evidence that soil may play an important role in transmission of zoonotic parasite diseases to human. In addition, control of high population of animals such as stray dogs and cats is necessary to reduce the distribution of parasites. Key words: Prevalence, parasites, flotation method, Tehran.

  17. Clinical Correlates of Diarrhea and Gut Parasites among Human Immunodeficiency Virus Seropositive Patients

    Directory of Open Access Journals (Sweden)

    Elvis Bisong

    2017-09-01

    Full Text Available Cluster differentiation 4 (CD4 count estimation, which is not readily available in most resource poor settings in Nigeria, is an important indexdetermining commencement of antiretroviral therapy (ART. It is imperative for physicians who come in contact with these patients in such settings to recognize other parameters to evaluate these patients. The clinical correlates of diarrhea and gut parasites among human immunodeficiency virus (HIV-seropositive patients attending our special treatment clinic were studied. Three hundred and forty consenting HIV-positive adult subjects were enrolled. Their stool and blood specimens were collected for a period of three months. Stool samples were analyzed for the presence of diarrhea and gut parasites. The patients were clinically evaluated by physical examination for the presence of pallor, dehydration, oral thrush, wasting lymphadenopathy, dermatitis, skin hyperpigmentation, and finger clubbing. Participants with diarrhea represented 14.1% of the population, while 21.5% harbored one or more parasites. In the subjects with diarrhea, 14.6% harbored gut parasites. The presence of diarrhea was associated with a low CD4 count. Clinically, oral thrush, wasting, and rashes were more reliable predictors of low CD4 count levels; whereas, the presence of pallor, dehydration, wasting, and rashes correlated with the presence of diarrhea. HIV patients presenting with pallor, dehydration, wasting, and rashes should be evaluated for the presence of diarrhea. The clinical variables associated with low CD4 count in this study may guide commencing antiretroviral therapy in resource poor settings.

  18. Environmental temperature affects prevalence of blood parasites of birds on an elevation gradient: implications for disease in a warming climate.

    Directory of Open Access Journals (Sweden)

    Itzel Zamora-Vilchis

    Full Text Available BACKGROUND: The rising global temperature is predicted to expand the distribution of vector-borne diseases both in latitude and altitude. Many host communities could be affected by increased prevalence of disease, heightening the risk of extinction for many already threatened species. To understand how host communities could be affected by changing parasite distributions, we need information on the distribution of parasites in relation to variables like temperature and rainfall that are predicted to be affected by climate change. METHODOLOGY/PRINCIPAL FINDINGS: We determined relations between prevalence of blood parasites, temperature, and seasonal rainfall in a bird community of the Australian Wet Tropics along an elevation gradient. We used PCR screening to investigate the prevalence and lineage diversity of four genera of blood parasites (Plasmodium, Haemoproteus, Leucocytozoon and Trypanosoma in 403 birds. The overall prevalence of the four genera of blood parasites was 32.3%, with Haemoproteus the predominant genus. A total of 48 unique lineages were detected. Independent of elevation, parasite prevalence was positively and strongly associated with annual temperature. Parasite prevalence was elevated during the dry season. CONCLUSIONS/SIGNIFICANCE: Low temperatures of the higher elevations can help to reduce both the development of avian haematozoa and the abundance of parasite vectors, and hence parasite prevalence. In contrast, high temperatures of the lowland areas provide an excellent environment for the development and transmission of haematozoa. We showed that rising temperatures are likely to lead to increased prevalence of parasites in birds, and may force shifts of bird distribution to higher elevations. We found that upland tropical areas are currently a low-disease habitat and their conservation should be given high priority in management plans under climate change.

  19. Disease severity in patients with visceral leishmaniasis is not altered by co-infection with intestinal parasites

    Science.gov (United States)

    Adem, Emebet; Hailu, Asrat; Lemma, Mulualem; Fikre, Helina; Raynes, John; Tamiru, Aschalew; Mulugeta, Zemenay; Diro, Ermias; Toulza, Frederic; Shkedy, Ziv; Ayele, Tadesse; Modolell, Manuel; Munder, Markus; Müller, Ingrid; Takele, Yegnasew

    2017-01-01

    Visceral leishmaniasis (VL) is a neglected tropical disease that affects the poorest communities and can cause substantial morbidity and mortality. Visceral leishmaniasis is characterized by the presence of Leishmania parasites in the spleen, liver and bone marrow, hepatosplenomegaly, pancytopenia, prolonged fever, systemic inflammation and low body mass index (BMI). The factors impacting on the severity of VL are poorly characterized. Here we performed a cross-sectional study to assess whether co-infection of VL patients with intestinal parasites influences disease severity, assessed with clinical and haematological data, inflammation, cytokine profiles and BMI. Data from VL patients was similar to VL patients co-infected with intestinal parasites, suggesting that co-infection of VL patients with intestinal parasites does not alter disease severity. PMID:28732017

  20. Disease severity in patients with visceral leishmaniasis is not altered by co-infection with intestinal parasites.

    Science.gov (United States)

    Tajebe, Fitsumbrhan; Getahun, Mulusew; Adem, Emebet; Hailu, Asrat; Lemma, Mulualem; Fikre, Helina; Raynes, John; Tamiru, Aschalew; Mulugeta, Zemenay; Diro, Ermias; Toulza, Frederic; Shkedy, Ziv; Ayele, Tadesse; Modolell, Manuel; Munder, Markus; Müller, Ingrid; Takele, Yegnasew; Kropf, Pascale

    2017-07-01

    Visceral leishmaniasis (VL) is a neglected tropical disease that affects the poorest communities and can cause substantial morbidity and mortality. Visceral leishmaniasis is characterized by the presence of Leishmania parasites in the spleen, liver and bone marrow, hepatosplenomegaly, pancytopenia, prolonged fever, systemic inflammation and low body mass index (BMI). The factors impacting on the severity of VL are poorly characterized. Here we performed a cross-sectional study to assess whether co-infection of VL patients with intestinal parasites influences disease severity, assessed with clinical and haematological data, inflammation, cytokine profiles and BMI. Data from VL patients was similar to VL patients co-infected with intestinal parasites, suggesting that co-infection of VL patients with intestinal parasites does not alter disease severity.

  1. Influenza as a human disease

    Indian Academy of Sciences (India)

    First page Back Continue Last page Graphics. Influenza as a human disease. Commonly perceived as a mild disease, affects every one, sometimes a couple of times in a year. Globally, seasonal influenza epidemics result in about three to five million yearly cases of severe illness and about 250,000 to 500,000 yearly ...

  2. Human communicable diseases

    International Nuclear Information System (INIS)

    2003-01-01

    The rising incidence of malaria and tuberculosis in sub-Saharan Africa is causing great hardship, not only to the individuals affected but also to the economies of the countries where they are rife. Both diseases are becoming more resistant to the drugs that are currently available for treatment and drug resistant strains are posing a global threat. The International Atomic Energy Agency (IAEA) is responding by sponsoring a programme to build technical competency in molecular and radioisotope-based techniques. (IAEA)

  3. Parasitic Zoonoses in Humans and Their Dogs from a Rural Community of Tropical Mexico

    Directory of Open Access Journals (Sweden)

    Antonio Ortega-Pacheco

    2015-01-01

    Full Text Available A cross-sectional study was made on 89 inhabitants and their dogs from a rural community of Yucatan, Mexico, to determine the serological prevalence of some zoonotic parasitic agents. Samples were taken to monitor the presence and intensity of infection with gastrointestinal parasites in dogs. In humans, the serological prevalence of T. canis, T. gondii, and T. spiralis was 29.2%, 91.0%, and 6.7%, respectively. No associations were found between positive cases and studied variables. From the total of blood samples taken from dogs, 87 (97.6% were seropositive to T. gondii; only 52 viable fecal samples were collected from dogs of which 46.2% had the presence of gastrointestinal parasites with low to moderate intensity; from those, 12% had the presence of T. canis. This study demonstrates the presence of the studied zoonotic agents in the area particularly T. gondii which suggest a common source of infection in dogs and humans and a high number of oocyts present in the environment. Preventive measures must be designed towards good prophylactic practices in domestic and backyard animals (T. canis and T. spiralis. Contaminated sources with T. gondii (food and water should be further investigated in order to design effective control measures.

  4. Transcriptionally Driven DNA Replication Program of the Human Parasite Leishmania major

    Directory of Open Access Journals (Sweden)

    Rodrigo Lombraña

    2016-08-01

    Full Text Available Faithful inheritance of eukaryotic genomes requires the orchestrated activation of multiple DNA replication origins (ORIs. Although origin firing is mechanistically conserved, how origins are specified and selected for activation varies across different model systems. Here, we provide a complete analysis of the nucleosomal landscape and replication program of the human parasite Leishmania major, building on a better evolutionary understanding of replication organization in Eukarya. We found that active transcription is a driving force for the nucleosomal organization of the L. major genome and that both the spatial and the temporal program of DNA replication can be explained as associated to RNA polymerase kinetics. This simple scenario likely provides flexibility and robustness to deal with the environmental changes that impose alterations in the genetic programs during parasitic life cycle stages. Our findings also suggest that coupling replication initiation to transcription elongation could be an ancient solution used by eukaryotic cells for origin maintenance.

  5. Lipid Bodies as Sites of Prostaglandin E2 Synthesis During Chagas Disease: Impact in the Parasite Escape Mechanism

    Directory of Open Access Journals (Sweden)

    Patrícia E. de Almeida

    2018-03-01

    Full Text Available During Chagas disease, the Trypanosoma cruzi can induce some changes in the host cells in order to escape or manipulate the host immune response. The modulation of the lipid metabolism in the host phagocytes or in the parasite itself is one feature that has been observed. The goal of this mini review is to discuss the mechanisms that regulate intracellular lipid body (LB biogenesis in the course of this parasite infection and their meaning to the pathophysiology of the disease. The interaction host–parasite induces LB (or lipid droplet formation in a Toll-like receptor 2-dependent mechanism in macrophages and is enhanced by apoptotic cell uptake. Simultaneously, there is a lipid accumulation in the parasite due to the incorporation of host fatty acids. The increase in the LB accumulation during infection is correlated with an increase in the synthesis of PGE2 within the host cells and the parasite LBs. Moreover, the treatment with fatty acid synthase inhibitor C75 or non-steroidal anti-inflammatory drugs such as NS-398 and aspirin inhibited the LB biogenesis and also induced the down modulation of the eicosanoid production and the parasite replication. These findings show that LBs are organelles up modulated during the course of infection. Furthermore, the biogenesis of the LB is involved in the lipid mediator generation by both the macrophages and the parasite triggering escape mechanisms.

  6. Viral diseases and human evolution

    Directory of Open Access Journals (Sweden)

    Leal Élcio de Souza

    2000-01-01

    Full Text Available The interaction of man with viral agents was possibly a key factor shaping human evolution, culture and civilization from its outset. Evidence of the effect of disease, since the early stages of human speciation, through pre-historical times to the present suggest that the types of viruses associated with man changed in time. As human populations progressed technologically, they grew in numbers and density. As a consequence different viruses found suitable conditions to thrive and establish long-lasting associations with man. Although not all viral agents cause disease and some may in fact be considered beneficial, the present situation of overpopulation, poverty and ecological inbalance may have devastating effets on human progress. Recently emerged diseases causing massive pandemics (eg., HIV-1 and HCV, dengue, etc. are becoming formidable challenges, which may have a direct impact on the fate of our species.

  7. The magnitude and risk factors of intestinal parasitic infection in relation to Human Immunodeficiency Virus infection and immune status, at ALERT Hospital, Addis Ababa, Ethiopia.

    Science.gov (United States)

    Taye, Biruhalem; Desta, Kassu; Ejigu, Selamawit; Dori, Geme Urge

    2014-06-01

    Human Immunodeficiency Virus (HIV) and intestinal parasitic infections are among the main health problems in developing countries like Ethiopia. Particularly, co-infections of these diseases would worsen the progression of HIV to Acquired Immunodeficiency Syndrome (AIDS). The purpose of this study was to determine the magnitude and risk factors for intestinal parasites in relation to HIV infection and immune status. The study was conducted in (1) HIV positive on antiretroviral therapy (ART) and (2) ART naïve HIV positive patients, and (3) HIV-negative individuals, at All African Leprosy and Tuberculosis (TB) Eradication and Rehabilitation Training Center (ALERT) hospital in Addis Ababa, Ethiopia. Study participants were interviewed using structured questionnaires to obtain socio-demographic characteristics and assess risk factors associated with intestinal parasitic infection. Intestinal parasites were identified from fecal samples by direct wet mount, formol ether concentration, and modified Ziehl-Neelsen staining techniques. The immune status was assessed by measuring whole blood CD4 T-cell count. The overall magnitude of intestinal parasite was 35.08%. This proportion was different among study groups with 39.2% (69/176), 38.83% (40/103) and 27.14% (38/140) in ART naïve HIV positives patients, in HIV negatives, and in HIV positive on ART patients respectively. HIV positive patients on ART had significantly lower magnitude of intestinal parasitic infection compared to HIV negative individuals. Intestinal helminths were significantly lower in HIV positive on ART and ART naïve patients than HIV negatives. Low monthly income, and being married, divorced or widowed were among the socio-demographic characteristics associated with intestinal parasitic infection. No association was observed between the magnitude of intestinal parasites and CD4 T-cell count. However, Cryptosporidium parvum, and Isospora belli were exclusively identified in individuals with CD4 T

  8. Parasites and diseases in marine copepods: Challenges for future mass-production of live feed for fish larva production

    DEFF Research Database (Denmark)

    Skovgaard, Alf

    Copepods are the natural food for many marine fish larvae, and the use of cultured copepods as life feed is, therefore, becoming increasingly important as more marine fish species are being produced in aquaculture. Large-scale cultivation of copepods may be challenged by diseases and parasites....... In nature, marine copepods are hosts for parasitic organisms of many different taxonomic groups, including e.g. dinoflagellates, ciliates, paramyxans, nematodes and even other crustaceans. In addition, several parasites of copepods have yet not been investigated in relation to their taxonomic affiliation...

  9. The prevalence and diversity of intestinal parasitic infections in humans and domestic animals in a rural Cambodian village.

    Science.gov (United States)

    Schär, Fabian; Inpankaew, Tawin; Traub, Rebecca J; Khieu, Virak; Dalsgaard, Anders; Chimnoi, Wissanuwat; Chhoun, Chamnan; Sok, Daream; Marti, Hanspeter; Muth, Sinuon; Odermatt, Peter

    2014-08-01

    In Cambodia, intestinal parasitic infections are prevalent in humans and particularly in children. Yet, information on potentially zoonotic parasites in animal reservoir hosts is lacking. In May 2012, faecal samples from 218 humans, 94 dogs and 76 pigs were collected from 67 households in Dong village, Preah Vihear province, Cambodia. Faecal samples were examined microscopically using sodium nitrate and zinc sulphate flotation methods, the Baermann method, Koga Agar plate culture, formalin-ether concentration technique and Kato Katz technique. PCR was used to confirm hookworm, Ascaris spp., Giardia spp. and Blastocystis spp. Major gastrointestinal parasitic infections found in humans included hookworms (63.3%), Entamoeba spp. (27.1%) and Strongyloides stercoralis (24.3%). In dogs, hookworm (80.8%), Spirometra spp. (21.3%) and Strongyloides spp. (14.9%) were most commonly detected and in pigs Isospora suis (75.0%), Oesophagostomum spp. (73.7%) and Entamoeba spp. (31.6%) were found. Eleven parasite species were detected in dogs (eight helminths and three protozoa), seven of which have zoonotic potential, including hookworm, Strongyloides spp., Trichuris spp., Toxocara canis, Echinostoma spp., Giardia duodenalis and Entamoeba spp. Five of the parasite species detected in pigs also have zoonotic potential, including Ascaris spp., Trichuris spp., Capillaria spp., Balantidium coli and Entamoeba spp. Further molecular epidemiological studies will aid characterisation of parasite species and genotypes and allow further insight into the potential for zoonotic cross transmission of parasites in this community. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  10. Cohesin and Human Disease

    Science.gov (United States)

    Liu, Jinglan; Krantz, Ian D.

    2016-01-01

    Cornelia de Lange syndrome (CdLS) is a dominant multisystem disorder caused by a disruption of cohesin function. The cohesin ring complex is composed of four protein subunits and more than 25 additional proteins involved in its regulation. The discovery that this complex also has a fundamental role in long-range regulation of transcription in Drosophila has shed light on the mechanism likely responsible for its role in development. In addition to the three cohesin proteins involved in CdLS, a second multisystem, recessively inherited, developmental disorder, Roberts-SC phocomelia, is caused by mutations in another regulator of the cohesin complex, ESCO2. Here we review the phenotypes of these disorders, collectively termed cohesinopathies, as well as the mechanism by which cohesin disruption likely causes these diseases. PMID:18767966

  11. Disease ecology across soil boundaries: effects of below-ground fungi on above-ground host-parasite interactions.

    Science.gov (United States)

    Tao, Leiling; Gowler, Camden D; Ahmad, Aamina; Hunter, Mark D; de Roode, Jacobus C

    2015-10-22

    Host-parasite interactions are subject to strong trait-mediated indirect effects from other species. However, it remains unexplored whether such indirect effects may occur across soil boundaries and connect spatially isolated organisms. Here, we demonstrate that, by changing plant (milkweed Asclepias sp.) traits, arbuscular mycorrhizal fungi (AMF) significantly affect interactions between a herbivore (the monarch butterfly Danaus plexippus) and its protozoan parasite (Ophryocystis elektroscirrha), which represents an interaction across four biological kingdoms. In our experiment, AMF affected parasite virulence, host resistance and host tolerance to the parasite. These effects were dependent on both the density of AMF and the identity of milkweed species: AMF indirectly increased disease in monarchs reared on some species, while alleviating disease in monarchs reared on other species. The species-specificity was driven largely by the effects of AMF on both plant primary (phosphorus) and secondary (cardenolides; toxins in milkweeds) traits. Our study demonstrates that trait-mediated indirect effects in disease ecology are extensive, such that below-ground interactions between AMF and plant roots can alter host-parasite interactions above ground. In general, soil biota may play an underappreciated role in the ecology of many terrestrial host-parasite systems. © 2015 The Author(s).

  12. Disease ecology across soil boundaries: effects of below-ground fungi on above-ground host–parasite interactions

    Science.gov (United States)

    Tao, Leiling; Gowler, Camden D.; Ahmad, Aamina; Hunter, Mark D.; de Roode, Jacobus C.

    2015-01-01

    Host–parasite interactions are subject to strong trait-mediated indirect effects from other species. However, it remains unexplored whether such indirect effects may occur across soil boundaries and connect spatially isolated organisms. Here, we demonstrate that, by changing plant (milkweed Asclepias sp.) traits, arbuscular mycorrhizal fungi (AMF) significantly affect interactions between a herbivore (the monarch butterfly Danaus plexippus) and its protozoan parasite (Ophryocystis elektroscirrha), which represents an interaction across four biological kingdoms. In our experiment, AMF affected parasite virulence, host resistance and host tolerance to the parasite. These effects were dependent on both the density of AMF and the identity of milkweed species: AMF indirectly increased disease in monarchs reared on some species, while alleviating disease in monarchs reared on other species. The species-specificity was driven largely by the effects of AMF on both plant primary (phosphorus) and secondary (cardenolides; toxins in milkweeds) traits. Our study demonstrates that trait-mediated indirect effects in disease ecology are extensive, such that below-ground interactions between AMF and plant roots can alter host–parasite interactions above ground. In general, soil biota may play an underappreciated role in the ecology of many terrestrial host–parasite systems. PMID:26468247

  13. Look what the cat dragged in: do parasites contribute to human cultural diversity?

    Science.gov (United States)

    Lafferty, Kevin D.

    2005-01-01

    If human culture emerges from the modal personality of a population, can global variation in parasitism that affects personality lead to cultural diversity among nations? The answer could help explain why people seem to vary so much from one land to another. Thomas et al. (2005) review how parasites manipulate behaviour, including human behaviour. To quote them, “The rabies virus lives in the brain, affording the virus ample opportunity to directly affect host behaviour. Rabid animals do show changes in behaviour, including increased aggression and biting.” Rabies affects a wide range of mammals and the aggressive biting associated with furious rabies appears to increase transmission. The personality transformation of infected humans can be horrifying, transforming loved ones into thrashing, baying beasts. Not coincidentally, in Europe, past periods of rabies outbreaks correspond to increases in werewolf trials. Although rabies can have a dramatic effect, the present rarity of human rabies cases and the availability of a vaccine, means that the behavioural effects of rabies are primarily an illustrative curiosity.

  14. The Clp Chaperones and Proteases of the Human Malaria Parasite Plasmodium falciparum

    Energy Technology Data Exchange (ETDEWEB)

    Bakkouri, Majida El; Pow, Andre; Mulichak, Anne; Cheung, Kevin L.Y.; Artz, Jennifer D.; Amani, Mehrnaz; Fell, Stuart; de Koning-Ward, Tania F.; Goodman, C. Dean; McFadden, Geoffrey I.; Ortega, Joaquin; Hui, Raymond; Houry, Walid A. (McMaster U.); (Melbourne); (Toronto); (Deakin); (HWMRI)

    2015-02-09

    The Clp chaperones and proteases play an important role in protein homeostasis in the cell. They are highly conserved across prokaryotes and found also in the mitochondria of eukaryotes and the chloroplasts of plants. They function mainly in the disaggregation, unfolding and degradation of native as well as misfolded proteins. Here, we provide a comprehensive analysis of the Clp chaperones and proteases in the human malaria parasite Plasmodium falciparum. The parasite contains four Clp ATPases, which we term PfClpB1, PfClpB2, PfClpC and PfClpM. One PfClpP, the proteolytic subunit, and one PfClpR, which is an inactive version of the protease, were also identified. Expression of all Clp chaperones and proteases was confirmed in blood-stage parasites. The proteins were localized to the apicoplast, a non-photosynthetic organelle that accommodates several important metabolic pathways in P. falciparum, with the exception of PfClpB2 (also known as Hsp101), which was found in the parasitophorous vacuole. Both PfClpP and PfClpR form mostly homoheptameric rings as observed by size-exclusion chromatography, analytical ultracentrifugation and electron microscopy. The X-ray structure of PfClpP showed the protein as a compacted tetradecamer similar to that observed for Streptococcus pneumoniae and Mycobacterium tuberculosis ClpPs. Our data suggest the presence of a ClpCRP complex in the apicoplast of P. falciparum.

  15. Natural infection of Plasmodium brasilianum in humans: Man and monkey share quartan malaria parasites in the Venezuelan Amazon.

    Science.gov (United States)

    Lalremruata, Albert; Magris, Magda; Vivas-Martínez, Sarai; Koehler, Maike; Esen, Meral; Kempaiah, Prakasha; Jeyaraj, Sankarganesh; Perkins, Douglas Jay; Mordmüller, Benjamin; Metzger, Wolfram G

    2015-09-01

    The quartan malaria parasite Plasmodium malariae is the widest spread and best adapted human malaria parasite. The simian Plasmodium brasilianum causes quartan fever in New World monkeys and resembles P. malariae morphologically. Since the genetics of the two parasites are nearly identical, differing only in a range of mutations expected within a species, it has long been speculated that the two are the same. However, no naturally acquired infection with parasites termed as P. brasilianum has been found in humans until now. We investigated malaria cases from remote Yanomami indigenous communities of the Venezuelan Amazon and analyzed the genes coding for the circumsporozoite protein (CSP) and the small subunit of ribosomes (18S) by species-specific PCR and capillary based-DNA sequencing. Based on 18S rRNA gene sequencing, we identified 12 patients harboring malaria parasites which were 100% identical with P. brasilianum isolated from the monkey, Alouatta seniculus. Translated amino acid sequences of the CS protein gene showed identical immunodominant repeat units between quartan malaria parasites isolated from both humans and monkeys. This study reports, for the first time, naturally acquired infections in humans with parasites termed as P. brasilianum. We conclude that quartan malaria parasites are easily exchanged between humans and monkeys in Latin America. We hypothesize a lack of host specificity in mammalian hosts and consider quartan malaria to be a true anthropozoonosis. Since the name P. brasilianum suggests a malaria species distinct from P. malariae, we propose that P. brasilianum should have a nomenclatorial revision in case further research confirms our findings. The expansive reservoir of mammalian hosts discriminates quartan malaria from other Plasmodium spp. and requires particular research efforts.

  16. Functional expression of parasite drug targets and their human orthologs in yeast.

    Directory of Open Access Journals (Sweden)

    Elizabeth Bilsland

    2011-10-01

    Full Text Available The exacting nutritional requirements and complicated life cycles of parasites mean that they are not always amenable to high-throughput drug screening using automated procedures. Therefore, we have engineered the yeast Saccharomyces cerevisiae to act as a surrogate for expressing anti-parasitic targets from a range of biomedically important pathogens, to facilitate the rapid identification of new therapeutic agents.Using pyrimethamine/dihydrofolate reductase (DHFR as a model parasite drug/drug target system, we explore the potential of engineered yeast strains (expressing DHFR enzymes from Plasmodium falciparum, P. vivax, Homo sapiens, Schistosoma mansoni, Leishmania major, Trypanosoma brucei and T. cruzi to exhibit appropriate differential sensitivity to pyrimethamine. Here, we demonstrate that yeast strains (lacking the major drug efflux pump, Pdr5p expressing yeast ((ScDFR1, human ((HsDHFR, Schistosoma ((SmDHFR, and Trypanosoma ((TbDHFR and (TcDHFR DHFRs are insensitive to pyrimethamine treatment, whereas yeast strains producing Plasmodium ((PfDHFR and (PvDHFR DHFRs are hypersensitive. Reassuringly, yeast strains expressing field-verified, drug-resistant mutants of P. falciparum DHFR ((Pfdhfr(51I,59R,108N are completely insensitive to pyrimethamine, further validating our approach to drug screening. We further show the versatility of the approach by replacing yeast essential genes with other potential drug targets, namely phosphoglycerate kinases (PGKs and N-myristoyl transferases (NMTs.We have generated a number of yeast strains that can be successfully harnessed for the rapid and selective identification of urgently needed anti-parasitic agents.

  17. [Analysis on theses of the Chinese Journal of Parasitology and Parasitic Diseases in 2009-2012].

    Science.gov (United States)

    Yi, Feng-Yun; Qu, Lin-Ping; Yan, He; Sheng, Hui-Feng

    2013-12-01

    The published articles at the Chinese Journal of Parasitology and Parasitic Diseases in 2009-2012 were statistically analyzed. Among 547 papers published in the four years, original articles occupied 45.3% (248/547). The number of authors was 2712, with an average cooperation degree of 5.0, and the co-authorship accounted for 95.4% of the papers. Authors were mainly from colleges/universities (51.9%, 284/547), institutions for disease control (34.4%, 188/547) and hospitals health centers (13.7%, 75/547). The average publishing delay was 212, 141, 191 and 207 d in 2009-2012. Statistical analysis reflected the characteristics and academic level for improving the quality of the journal, and revealed the latest development and trends.

  18. DNA typing of ancient parasite eggs from environmental samples identifies human and animal worm infections in Viking-age settlement

    DEFF Research Database (Denmark)

    Søe, Martin Jensen; Fredensborg, Brian Lund; Nejsum, Peter

    Human worm infections have, to a large extent, been eradicated in countries with high sanitary standards by preventing the fecal-oral transmission of infective eggs. It is possible to study parasite infections among past populations by retrieving and analyzing parasite eggs using paleoparasitolog......-age. Further, eggs of the Liver Fluke (Fasciola hepatica), whose primary hosts are cows and sheep, are identified indicating that grazing animals were kept in close proximity of the settlement....

  19. Evasion and Immuno-Endocrine Regulation in Parasite Infection: Two Sides of the Same Coin in Chagas Disease?

    Science.gov (United States)

    Morrot, Alexandre; Villar, Silvina R; González, Florencia B; Pérez, Ana R

    2016-01-01

    Chagas disease is a serious illness caused by the protozoan parasite Trypanosoma cruzi. Nearly 30% of chronically infected people develop cardiac, digestive, or mixed alterations, suggesting a broad range of host-parasite interactions that finally impact upon chronic disease outcome. The ability of T. cruzi to persist and cause pathology seems to depend on diverse factors like T. cruzi strains, the infective load and the route of infection, presence of virulence factors, the parasite capacity to avoid protective immune response, the strength and type of host defense mechanisms and the genetic background of the host. The host-parasite interaction is subject to a constant neuro-endocrine regulation that is thought to influence the adaptive immune system, and as the infection proceeds it can lead to a broad range of outcomes, ranging from pathogen elimination to its continued persistence in the host. In this context, T. cruzi evasion strategies and host defense mechanisms can be envisioned as two sides of the same coin, influencing parasite persistence and different outcomes observed in Chagas disease. Understanding how T. cruzi evade host's innate and adaptive immune response will provide important clues to better dissect mechanisms underlying the pathophysiology of Chagas disease.

  20. Comparison of parasite loads in serum and blood samples from patients in acute and chronic phases of Chagas disease.

    Science.gov (United States)

    Hernández, Carolina; Teherán, Aníbal; Flórez, Carolina; Ramírez, Juan David

    2018-04-17

    Molecular methods have been developed for the detection and quantification of Trypanosoma cruzi DNA in blood samples from patients with Chagas disease. However, aspects of sample processing necessary for quantitative real-time PCR (qPCR), such as the addition of guanidine hydrochloride to whole blood samples, may limit timely access to molecular diagnosis. We analysed 169 samples from serum and guanidine-EDTA blood (GEB) obtained from patients in acute and chronic phases of Chagas disease. We applied qPCR targeted to the satellite DNA region. Finally, we compared the parasite loads and cycle of threshold values of the qPCR. The results confirmed the usefulness of serum samples for the detection and quantification of parasite DNA in patients with Chagas disease, especially in the acute phase. However, the parasite loads detected in serum samples from patients in the chronic phase were lower than those detected in GEB samples. The epidemiological implications of the findings are herein discussed.

  1. A European network for food-borne parasites (Euro-FBP: meeting report on ‘Analytical methods for food-borne parasites in human and veterinary diagnostics and in food matrices’

    Directory of Open Access Journals (Sweden)

    Christian Klotz

    2017-11-01

    Full Text Available Abstract Food-borne parasites (FBPs are a neglected topic in food safety, partly due to a lack of awareness of their importance for public health, especially as symptoms tend not to develop immediately after exposure. In addition, methodological difficulties with both diagnosis in infected patients and detection in food matrices result in under-detection and therefore the potential for underestimation of their burden on our societies. This, in consequence, leads to lower prioritization for basic research, e.g. for development new and more advanced detection methods for different food matrices and diagnostic samples, and thus a vicious circle of neglect and lack of progress is propagated. The COST Action FA1408, A European Network for Foodborne Parasites (Euro-FBP aims to combat the impact of FBP on public health by facilitating the multidisciplinary cooperation and partnership between groups of researchers and between researchers and stakeholders. The COST Action TD1302, the European Network for cysticercosis/taeniosis, CYSTINET, has a specific focus on Taenia solium and T. saginata, two neglected FBPs, and aims to advance knowledge and understanding of these zoonotic disease complexes via collaborations in a multidisciplinary scientific network. This report summarizes the results of a meeting within the Euro-FBP consortium entitled ‘Analytical methods for food-borne parasites in human and veterinary diagnostics and in food matrices’ and of the joined Euro-FBP and CYSTINET meeting.

  2. Ecological host fitting of Trypanosoma cruzi TcI in Bolivia: mosaic population structure, hybridization and a role for humans in Andean parasite dispersal.

    Science.gov (United States)

    Messenger, Louisa A; Garcia, Lineth; Vanhove, Mathieu; Huaranca, Carlos; Bustamante, Marinely; Torrico, Marycruz; Torrico, Faustino; Miles, Michael A; Llewellyn, Martin S

    2015-05-01

    An improved understanding of how a parasite species exploits its genetic repertoire to colonize novel hosts and environmental niches is crucial to establish the epidemiological risk associated with emergent pathogenic genotypes. Trypanosoma cruzi, a genetically heterogeneous, multi-host zoonosis, provides an ideal system to examine the sylvatic diversification of parasitic protozoa. In Bolivia, T. cruzi I, the oldest and most widespread genetic lineage, is pervasive across a range of ecological clines. High-resolution nuclear (26 loci) and mitochondrial (10 loci) genotyping of 199 contemporaneous sylvatic TcI clones was undertaken to provide insights into the biogeographical basis of T. cruzi evolution. Three distinct sylvatic parasite transmission cycles were identified: one highland population among terrestrial rodent and triatomine species, composed of genetically homogenous strains (Ar = 2.95; PA/L = 0.61; DAS = 0.151), and two highly diverse, parasite assemblages circulating among predominantly arboreal mammals and vectors in the lowlands (Ar = 3.40 and 3.93; PA/L = 1.12 and 0.60; DAS = 0.425 and 0.311, respectively). Very limited gene flow between neighbouring terrestrial highland and arboreal lowland areas (distance ~220 km; FST = 0.42 and 0.35) but strong connectivity between ecologically similar but geographically disparate terrestrial highland ecotopes (distance >465 km; FST = 0.016-0.084) strongly supports ecological host fitting as the predominant mechanism of parasite diversification. Dissimilar heterozygosity estimates (excess in highlands, deficit in lowlands) and mitochondrial introgression among lowland strains may indicate fundamental differences in mating strategies between populations. Finally, accelerated parasite dissemination between densely populated, highland areas, compared to uninhabited lowland foci, likely reflects passive, long-range anthroponotic dispersal. The impact of humans on the risk of epizootic Chagas disease transmission in

  3. Study of the gastrointestinal parasitic fauna of captive non-human primates (Macaca fascicularis).

    Science.gov (United States)

    Zanzani, Sergio Aurelio; Gazzonis, Alessia Libera; Epis, Sara; Manfredi, Maria Teresa

    2016-01-01

    The aim of this study was to examine helminths and protozoans in cynomolgus macaques (Macaca fascicularis) imported from registered breeding facilities in China and their relation to health risks for non-human primate handlers in biomedical research centers and in breeding facilities. Fresh fecal samples were collected from a total of 443 M. fascicularis and analyzed by copromicroscopical analysis, immunoenzymatic, or molecular assays. As to helminths, whose eggs were shed in 2.03% of the samples, Trichuris and Oesophagostomum were the only two taxa found, with low prevalence and low eggs per gram (EPG) values. Protozoans were more frequently detected (87.40%), with Entamoeba coli (85.19%) and Endolimax nana (79.26%) as the most prevalent species shed. Other parasites found by fecal smear examination were uninucleated-cyst-producing Entamoebas (78.52%), Iodamoeba bütschlii (42.96%), and Chilomastix mesnili (24.44%), while cysts of Balantidium coli (22.2%) were only observed by sedimentation. No coproantigens of Giardia duodenalis, Cryptosporidium spp., and Entamoeba histolytica complex were detected. Blastocystis sp. infection was noticed in 87.63% of macaques by PCR. These cynomolgus monkeys were infected with many subtypes (ST1, ST2, ST3, ST5, and ST7), where the predominant Blastocystis sp. subtypes were ST2 (77.5%), followed by ST1 (63.5%). Data collected confirmed the presence of potentially zoonotic parasites and a high parasite diversity, suggesting the need for appropriate and sensitive techniques to adequately control them and related health risks for handlers of non-human primates in biomedical research centers and in breeding facilities.

  4. Leukocyte Lysis and Cytokine Induction by the Human Sexually Transmitted Parasite Trichomonas vaginalis.

    Directory of Open Access Journals (Sweden)

    Frances Mercer

    2016-08-01

    Full Text Available Trichomonas vaginalis (Tv is an extracellular protozoan parasite that causes the most common non-viral sexually transmitted infection: trichomoniasis. While acute symptoms in women may include vaginitis, infections are often asymptomatic, but can persist and are associated with medical complications including increased HIV susceptibility, infertility, pre-term labor, and higher incidence of cervical cancer. Heightened inflammation resulting from Tv infection could account for these complications. Effective cellular immune responses to Tv have not been characterized, and re-infection is common, suggesting a dysfunctional adaptive immune response. Using primary human leukocyte components, we have established an in vitro co-culture system to assess the interaction between Tv and the cells of the human immune system. We determined that in vitro, Tv is able to lyse T-cells and B-cells, showing a preference for B-cells. We also found that Tv lysis of lymphocytes was mediated by contact-dependent and soluble factors. Tv lysis of monocytes is far less efficient, and almost entirely contact-dependent. Interestingly, a common symbiont of Tv, Mycoplasma hominis, did not affect cytolytic activity of the parasite, but had a major impact on cytokine responses. M. hominis enabled more diverse inflammatory cytokine secretion in response to Tv and, of the cytokines tested, Tv strains cleared of M. hominis induced only IL-8 secretion from monocytes. The quality of the adaptive immune response to Tv is therefore likely influenced by Tv symbionts, commensals, and concomitant infections, and may be further complicated by direct parasite lysis of effector immune cells.

  5. Systematic analysis of FKBP inducible degradation domain tagging strategies for the human malaria parasite Plasmodium falciparum.

    Directory of Open Access Journals (Sweden)

    Mauro Ferreira de Azevedo

    Full Text Available Targeted regulation of protein levels is an important tool to gain insights into the role of proteins essential to cell function and development. In recent years, a method based on mutated forms of the human FKBP12 has been established and used to great effect in various cell types to explore protein function. The mutated FKBP protein, referred to as destabilization domain (DD tag when fused with a native protein at the N- or C-terminus targets the protein for proteosomal degradation. Regulated expression is achieved via addition of a compound, Shld-1, that stabilizes the protein and prevents degradation. A limited number of studies have used this system to provide powerful insight into protein function in the human malaria parasite Plasmodium falciparum. In order to better understand the DD inducible system in P. falciparum, we studied the effect of Shld-1 on parasite growth, demonstrating that although development is not impaired, it is delayed, requiring the appropriate controls for phenotype interpretation. We explored the quantified regulation of reporter Green Fluorescent Protein (GFP and luciferase constructs fused to three DD variants in parasite cells either via transient or stable transfection. The regulation obtained with the original FKBP derived DD domain was compared to two triple mutants DD24 and DD29, which had been described to provide better regulation for C-terminal tagging in other cell types. When cloned to the C-terminal of reporter proteins, DD24 provided the strongest regulation allowing reporter activity to be reduced to lower levels than DD and to restore the activity of stabilised proteins to higher levels than DD29. Importantly, DD24 has not previously been applied to regulate proteins in P. falciparum. The possibility of regulating an exported protein was addressed by targeting the Ring-Infected Erythrocyte Surface Antigen (RESA at its C-terminus. The tagged protein demonstrated an important modulation of its

  6. Leukocyte Lysis and Cytokine Induction by the Human Sexually Transmitted Parasite Trichomonas vaginalis

    Science.gov (United States)

    Mercer, Frances; Diala, Fitz Gerald I.; Chen, Yi-Pei; Molgora, Brenda M.; Ng, Shek Hang; Johnson, Patricia J.

    2016-01-01

    Trichomonas vaginalis (Tv) is an extracellular protozoan parasite that causes the most common non-viral sexually transmitted infection: trichomoniasis. While acute symptoms in women may include vaginitis, infections are often asymptomatic, but can persist and are associated with medical complications including increased HIV susceptibility, infertility, pre-term labor, and higher incidence of cervical cancer. Heightened inflammation resulting from Tv infection could account for these complications. Effective cellular immune responses to Tv have not been characterized, and re-infection is common, suggesting a dysfunctional adaptive immune response. Using primary human leukocyte components, we have established an in vitro co-culture system to assess the interaction between Tv and the cells of the human immune system. We determined that in vitro, Tv is able to lyse T-cells and B-cells, showing a preference for B-cells. We also found that Tv lysis of lymphocytes was mediated by contact-dependent and soluble factors. Tv lysis of monocytes is far less efficient, and almost entirely contact-dependent. Interestingly, a common symbiont of Tv, Mycoplasma hominis, did not affect cytolytic activity of the parasite, but had a major impact on cytokine responses. M. hominis enabled more diverse inflammatory cytokine secretion in response to Tv and, of the cytokines tested, Tv strains cleared of M. hominis induced only IL-8 secretion from monocytes. The quality of the adaptive immune response to Tv is therefore likely influenced by Tv symbionts, commensals, and concomitant infections, and may be further complicated by direct parasite lysis of effector immune cells. PMID:27529696

  7. A novel PCR-based system for the detection of four species of human malaria parasites and Plasmodium knowlesi.

    Directory of Open Access Journals (Sweden)

    Kanako Komaki-Yasuda

    Full Text Available A microscopy-based diagnosis is the gold standard for the detection and identification of malaria parasites in a patient's blood. However, the detection of cases involving a low number of parasites and the differentiation of species sometimes requires a skilled microscopist. Although PCR-based diagnostic methods are already known to be very powerful tools, the time required to apply such methods is still much longer in comparison to traditional microscopic observation. Thus, improvements to PCR systems are sought to facilitate the more rapid and accurate detection of human malaria parasites Plasmodium falciparum, P. vivax, P. ovale, and P. malariae, as well as P. knowlesi, which is a simian malaria parasite that is currently widely distributed in Southeast Asia. A nested PCR that targets the small subunit ribosomal RNA genes of malaria parasites was performed using a "fast PCR enzyme". In the first PCR, universal primers for all parasite species were used. In the second PCR, inner-specific primers, which targeted sequences from P. falciparum, P. vivax, P. ovale, P. malariae, and P. knowlesi, were used. The PCR reaction time was reduced with the use of the "fast PCR enzyme", with only 65 minutes required to perform the first and second PCRs. The specific primers only reacted with the sequences of their targeted parasite species and never cross-reacted with sequences from other species under the defined PCR conditions. The diagnoses of 36 clinical samples that were obtained using this new PCR system were highly consistent with the microscopic diagnoses.

  8. Sex steroids, immune system, and parasitic infections: facts and hypotheses.

    Science.gov (United States)

    Nava-Castro, Karen; Hernández-Bello, Romel; Muñiz-Hernández, Saé; Camacho-Arroyo, Ignacio; Morales-Montor, Jorge

    2012-07-01

    It has been widely reported that the incidence and the severity of natural parasitic infections are different between males and females of several species, including humans. This sexual dimorphism involves a distinct exposure of males and females to various parasite infective stages, differential effects of sex steroids on immune cells, and direct effects of these steroids on parasites, among others. Typically, for a large number of parasitic diseases, the prevalence and intensity is higher in males than females; however, in several parasitic infections, males are more resistant than females. In the present work, we review the effects of sex hormones on immunity to protozoa and helminth parasites, which are the causal agents of several diseases in humans, and discuss the most recent research related to the role of sex steroids in the complex host-parasite relationship. © 2012 New York Academy of Sciences.

  9. Cockroaches as carriers of human intestinal parasites in two localities in Ethiopia.

    Science.gov (United States)

    Kinfu, Addisu; Erko, Berhanu

    2008-11-01

    A study was undertaken to assess the role of cockroaches as potential carriers of human intestinal parasites in Addis Ababa and Ziway, Ethiopia. A total of 6480 cockroaches were trapped from the two localities from October 2006 to March 2007. All the cockroaches trapped in Addis Ababa (n=2240) and almost 50% (2100/4240) of those trapped in Ziway were identified as Blattella germanica. The rest of the cockroaches trapped in Ziway were identified as Periplaneta brunnea (24.52%), Pycnoscelus surinamensis (16.03%) and Supella longipalpa (9.90%). Microscopic examination of the external body washes of pooled cockroaches and individual gut contents revealed that cockroaches are carriers of Entamoeba coli and Entamoeba histolytica/dispar cysts as well as Enterobius vermicularis, Trichuris trichiura, Taenia spp. and Ascaris lumbricoides ova. Besides their role as a nuisance, the present study further confirms that cockroaches serve as carriers of human intestinal parasites. The possible association of cockroaches with allergic conditions such as asthma is also discussed. Hence, appropriate control measures should be taken particularly to make hotels and residential areas free of cockroaches as they represent a health risk.

  10. Neglected Parasitic Infections: Toxocariasis

    Centers for Disease Control (CDC) Podcasts

    This podcast is an overview of the Clinician Outreach and Communication Activity (COCA) Call: Neglected Parasitic Infections in the United States. Neglected Parasitic Infections are a group of diseases that afflict vulnerable populations and are often not well studied or diagnosed. A subject matter expert from CDC's Division of Parasitic Diseases and Malaria describes the epidemiology, diagnosis, and treatment of toxocariasis.

  11. When More Transmission Equals Less Disease: Reconciling the Disconnect between Disease Hotspots and Parasite Transmission

    Science.gov (United States)

    Park, Andrew W.; Magori, Krisztian; White, Brad A.; Stallknecht, David E.

    2013-01-01

    The assumed straightforward connection between transmission intensity and disease occurrence impacts surveillance and control efforts along with statistical methodology, including parameter inference and niche modeling. Many infectious disease systems have the potential for this connection to be more complicated–although demonstrating this in any given disease system has remained elusive. Hemorrhagic disease (HD) is one of the most important diseases of white-tailed deer and is caused by viruses in the Orbivirus genus. Like many infectious diseases, the probability or severity of disease increases with age (after loss of maternal antibodies) and the probability of disease is lower upon re-infection compared to first infection (based on cross-immunity between virus strains). These broad criteria generate a prediction that disease occurrence is maximized at intermediate levels of transmission intensity. Using published US field data, we first fit a statistical model to predict disease occurrence as a function of seroprevalence (a proxy for transmission intensity), demonstrating that states with intermediate seroprevalence have the highest level of case reporting. We subsequently introduce an independently parameterized mechanistic model supporting the theory that high case reporting should come from areas with intermediate levels of transmission. This is the first rigorous demonstration of this phenomenon and illustrates that variation in transmission rate (e.g. along an ecologically-controlled transmission gradient) can create cryptic refuges for infectious diseases. PMID:23579922

  12. Proteins aggregation and human diseases

    Science.gov (United States)

    Hu, Chin-Kun

    2015-04-01

    Many human diseases and the death of most supercentenarians are related to protein aggregation. Neurodegenerative diseases include Alzheimer's disease (AD), Huntington's disease (HD), Parkinson's disease (PD), frontotemporallobar degeneration, etc. Such diseases are due to progressive loss of structure or function of neurons caused by protein aggregation. For example, AD is considered to be related to aggregation of Aβ40 (peptide with 40 amino acids) and Aβ42 (peptide with 42 amino acids) and HD is considered to be related to aggregation of polyQ (polyglutamine) peptides. In this paper, we briefly review our recent discovery of key factors for protein aggregation. We used a lattice model to study the aggregation rates of proteins and found that the probability for a protein sequence to appear in the conformation of the aggregated state can be used to determine the temperature at which proteins can aggregate most quickly. We used molecular dynamics and simple models of polymer chains to study relaxation and aggregation of proteins under various conditions and found that when the bending-angle dependent and torsion-angle dependent interactions are zero or very small, then protein chains tend to aggregate at lower temperatures. All atom models were used to identify a key peptide chain for the aggregation of insulin chains and to find that two polyQ chains prefer anti-parallel conformation. It is pointed out that in many cases, protein aggregation does not result from protein mis-folding. A potential drug from Chinese medicine was found for Alzheimer's disease.

  13. Immunity to parasitic infection

    National Research Council Canada - National Science Library

    Lamb, Tracey J

    2012-01-01

    .... Often endemic in developing countries many parasitic diseases are neglected in terms of research funding and much remains to be understood about parasites and the interactions they have with the immune system...

  14. Evidence that leishmania donovani utilizes a mannose receptor on human mononuclear phagocytes to establish intracellular parasitism

    International Nuclear Information System (INIS)

    Wilson, M.E.; Pearson, R.D.

    1986-01-01

    The pathogenic protozoan Leishmania donovani must gain entrance into mononuclear phagocytes to successfully parasitize man. The parasite's extracellular promastigote stage is ingested by human peripheral blood monocytes or monocyte-derived macrophages in the absence of serum, in a manner characteristic of receptor-mediated endocytosis. Remarkable similarities have been found between the macrophage receptor(s) for promastigotes and a previously characterized eucaryotic receptor system, the mannose/fucose receptor (MFR), that mediates the binding of zymosan particles and mannose- or fucose-terminal glycoconjugates to macrophages. Ingestion of promastigotes by monocyte-derived macrophages was inhibited by several MFR ligands; that is mannan, mannose-BSA and fucose-BSA. In contrast, promastigote ingestion by monocytes was unaffected by MFR ligands. Furthermore, attachment of promastigotes to macrophages, assessed by using cytochalasin D to prevent phagocytosis, was reduced 49.8% by mannan. Reorientation of the MFR to the ventral surface of the cell was achieved by plating macrophages onto mannan-coated coverslips, reducing MFR activity on the exposed cell surface by 94% as assessed by binding of 125 I-mannose-BSA. Under these conditions, ingestion of promastigotes was inhibited by 71.4%. Internalization of the MFR by exposure of macrophages to zymosan before infection with promastigotes resulted in a 62.3% decrease in parasite ingestion. Additionally, NH 4 Cl decreased macrophage ingestion of promastigotes by 38.2%. Subinhibitory concentration of NH 4 Cl (10 mM) and of mannan (0.25 mg/ml) together inhibited parsite ingestion by 76.4%

  15. Genome sequencing of chimpanzee malaria parasites reveals possible pathways of adaptation to human hosts

    KAUST Repository

    Otto, Thomas D.; Rayner, Julian C.; Bö hme, Ulrike; Pain, Arnab; Spottiswoode, Natasha; Sanders, Mandy; Quail, Michael; Ollomo, Benjamin; Renaud, Franç ois; Thomas, Alan W.; Prugnolle, Franck; Conway, David J.; Newbold, Chris; Berriman, Matthew

    2014-01-01

    related chimpanzee parasite species P. reichenowi, and obtaining partial sequence data from a more distantly related chimpanzee parasite (P. gaboni). The close relationship between P. reichenowi and P. falciparum is emphasized by almost complete

  16. A New High-Throughput Approach to Genotype Ancient Human Gastrointestinal Parasites.

    Science.gov (United States)

    Côté, Nathalie M L; Daligault, Julien; Pruvost, Mélanie; Bennett, E Andrew; Gorgé, Olivier; Guimaraes, Silvia; Capelli, Nicolas; Le Bailly, Matthieu; Geigl, Eva-Maria; Grange, Thierry

    2016-01-01

    Human gastrointestinal parasites are good indicators for hygienic conditions and health status of past and present individuals and communities. While microscopic analysis of eggs in sediments of archeological sites often allows their taxonomic identification, this method is rarely effective at the species level, and requires both the survival of intact eggs and their proper identification. Genotyping via PCR-based approaches has the potential to achieve a precise species-level taxonomic determination. However, so far it has mostly been applied to individual eggs isolated from archeological samples. To increase the throughput and taxonomic accuracy, as well as reduce costs of genotyping methods, we adapted a PCR-based approach coupled with next-generation sequencing to perform precise taxonomic identification of parasitic helminths directly from archeological sediments. Our study of twenty-five 100 to 7,200 year-old archeological samples proved this to be a powerful, reliable and efficient approach for species determination even in the absence of preserved eggs, either as a stand-alone method or as a complement to microscopic studies.

  17. Autophagy-related Atg8 localizes to the apicoplast of the human malaria parasite Plasmodium falciparum.

    Directory of Open Access Journals (Sweden)

    Kei Kitamura

    Full Text Available Autophagy is a membrane-mediated degradation process, which is governed by sequential functions of Atg proteins. Although Atg proteins are highly conserved in eukaryotes, protozoa possess only a partial set of Atg proteins. Nonetheless, almost all protozoa have the complete factors belonging to the Atg8 conjugation system, namely, Atg3, Atg4, Atg7, and Atg8. Here, we report the biochemical properties and subcellular localization of the Atg8 protein of the human malaria parasite Plasmodium falciparum (PfAtg8. PfAtg8 is expressed during intra-erythrocytic development and associates with membranes likely as a lipid-conjugated form. Fluorescence microscopy and immunoelectron microscopy show that PfAtg8 localizes to the apicoplast, a four membrane-bound non-photosynthetic plastid. Autophagosome-like structures are not observed in the erythrocytic stages. These data suggest that, although Plasmodium parasites have lost most Atg proteins during evolution, they use the Atg8 conjugation system for the unique organelle, the apicoplast.

  18. Host Mitochondrial Association Evolved in the Human Parasite Toxoplasma gondii via Neofunctionalization of a Gene Duplicate.

    Science.gov (United States)

    Adomako-Ankomah, Yaw; English, Elizabeth D; Danielson, Jeffrey J; Pernas, Lena F; Parker, Michelle L; Boulanger, Martin J; Dubey, Jitender P; Boyle, Jon P

    2016-05-01

    In Toxoplasma gondii, an intracellular parasite of humans and other animals, host mitochondrial association (HMA) is driven by a gene family that encodes multiple mitochondrial association factor 1 (MAF1) proteins. However, the importance of MAF1 gene duplication in the evolution of HMA is not understood, nor is the impact of HMA on parasite biology. Here we used within- and between-species comparative analysis to determine that the MAF1 locus is duplicated in T. gondii and its nearest extant relative Hammondia hammondi, but not another close relative, Neospora caninum Using cross-species complementation, we determined that the MAF1 locus harbors multiple distinct paralogs that differ in their ability to mediate HMA, and that only T. gondii and H. hammondi harbor HMA(+) paralogs. Additionally, we found that exogenous expression of an HMA(+) paralog in T. gondii strains that do not normally exhibit HMA provides a competitive advantage over their wild-type counterparts during a mouse infection. These data indicate that HMA likely evolved by neofunctionalization of a duplicate MAF1 copy in the common ancestor of T. gondii and H. hammondi, and that the neofunctionalized gene duplicate is selectively advantageous. Copyright © 2016 by the Genetics Society of America.

  19. Transcriptionally Driven DNA Replication Program of the Human Parasite Leishmania major.

    Science.gov (United States)

    Lombraña, Rodrigo; Álvarez, Alba; Fernández-Justel, José Miguel; Almeida, Ricardo; Poza-Carrión, César; Gomes, Fábia; Calzada, Arturo; Requena, José María; Gómez, María

    2016-08-09

    Faithful inheritance of eukaryotic genomes requires the orchestrated activation of multiple DNA replication origins (ORIs). Although origin firing is mechanistically conserved, how origins are specified and selected for activation varies across different model systems. Here, we provide a complete analysis of the nucleosomal landscape and replication program of the human parasite Leishmania major, building on a better evolutionary understanding of replication organization in Eukarya. We found that active transcription is a driving force for the nucleosomal organization of the L. major genome and that both the spatial and the temporal program of DNA replication can be explained as associated to RNA polymerase kinetics. This simple scenario likely provides flexibility and robustness to deal with the environmental changes that impose alterations in the genetic programs during parasitic life cycle stages. Our findings also suggest that coupling replication initiation to transcription elongation could be an ancient solution used by eukaryotic cells for origin maintenance. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  20. Natural infection of Plasmodium brasilianum in humans: Man and monkey share quartan malaria parasites in the Venezuelan Amazon

    Directory of Open Access Journals (Sweden)

    Albert Lalremruata

    2015-09-01

    Interpretation: This study reports, for the first time, naturally acquired infections in humans with parasites termed as P. brasilianum. We conclude that quartan malaria parasites are easily exchanged between humans and monkeys in Latin America. We hypothesize a lack of host specificity in mammalian hosts and consider quartan malaria to be a true anthropozoonosis. Since the name P. brasilianum suggests a malaria species distinct from P. malariae, we propose that P. brasilianum should have a nomenclatorial revision in case further research confirms our findings. The expansive reservoir of mammalian hosts discriminates quartan malaria from other Plasmodium spp. and requires particular research efforts.

  1. Transfer RNA and human disease

    Directory of Open Access Journals (Sweden)

    Jamie A Abbott

    2014-06-01

    Full Text Available Pathological mutations in tRNA genes and tRNA processing enzymes are numerous and result in very complicated clinical phenotypes. Mitochondrial tRNA (mt-tRNA genes are hotspots for pathological mutations and over 200 mt-tRNA mutations have been linked to various disease states. Often these mutations prevent tRNA aminoacylation. Disrupting this primary function affects protein synthesis and the expression, folding, and function of oxidative phosphorylation enzymes. Mitochondrial tRNA mutations manifest in a wide panoply of diseases related to cellular energetics, including COX deficiency (cytochrome C oxidase, mitochondrial myopathy, MERRF (Myoclonic Epilepsy with Ragged Red Fibers, and MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes. Diseases caused by mt-tRNA mutations can also affect very specific tissue types, as in the case of neurosensory non-syndromic hearing loss and pigmentary retinopathy, diabetes mellitus, and hypertrophic cardiomyopathy. Importantly, mitochondrial heteroplasmy plays a role in disease severity and age of onset as well. Not surprisingly, mutations in enzymes that modify cytoplasmic and mitochondrial tRNAs are also linked to a diverse range of clinical phenotypes. In addition to compromised aminoacylation of the tRNAs, mutated modifying enzymes can also impact tRNA expression and abundance, tRNA modifications, tRNA folding, and even tRNA maturation (e.g., splicing. Some of these pathological mutations in tRNAs and processing enzymes are likely to affect non-canonical tRNA functions, and contribute to the diseases without significantly impacting on translation. This chapter will review recent literature on the relation of mitochondrial and cytoplasmic tRNA, and enzymes that process tRNAs, to human disease. We explore the mechanisms involved in the clinical presentation of these various diseases with an emphasis on neurological disease.

  2. Transfer RNA and human disease.

    Science.gov (United States)

    Abbott, Jamie A; Francklyn, Christopher S; Robey-Bond, Susan M

    2014-01-01

    Pathological mutations in tRNA genes and tRNA processing enzymes are numerous and result in very complicated clinical phenotypes. Mitochondrial tRNA (mt-tRNA) genes are "hotspots" for pathological mutations and over 200 mt-tRNA mutations have been linked to various disease states. Often these mutations prevent tRNA aminoacylation. Disrupting this primary function affects protein synthesis and the expression, folding, and function of oxidative phosphorylation enzymes. Mitochondrial tRNA mutations manifest in a wide panoply of diseases related to cellular energetics, including COX deficiency (cytochrome C oxidase), mitochondrial myopathy, MERRF (Myoclonic Epilepsy with Ragged Red Fibers), and MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes). Diseases caused by mt-tRNA mutations can also affect very specific tissue types, as in the case of neurosensory non-syndromic hearing loss and pigmentary retinopathy, diabetes mellitus, and hypertrophic cardiomyopathy. Importantly, mitochondrial heteroplasmy plays a role in disease severity and age of onset as well. Not surprisingly, mutations in enzymes that modify cytoplasmic and mitochondrial tRNAs are also linked to a diverse range of clinical phenotypes. In addition to compromised aminoacylation of the tRNAs, mutated modifying enzymes can also impact tRNA expression and abundance, tRNA modifications, tRNA folding, and even tRNA maturation (e.g., splicing). Some of these pathological mutations in tRNAs and processing enzymes are likely to affect non-canonical tRNA functions, and contribute to the diseases without significantly impacting on translation. This chapter will review recent literature on the relation of mitochondrial and cytoplasmic tRNA, and enzymes that process tRNAs, to human disease. We explore the mechanisms involved in the clinical presentation of these various diseases with an emphasis on neurological disease.

  3. PROGRESSION OF DISEASES CAUSED BY THE OYSTER PARASITES, PERKINSUS MARINUS AND HAPLOSPORIDIUM NELSONI, IN CRASSOSTREA VIRGINICA ON CONSTRUCTED INTERTIDAL REEFS

    Science.gov (United States)

    The progression of diseases caused by the oyster parasites, Perkinsus marinus and Haplosporidium nelsoni, were evaluated by periodic sampling (May 1994-Dec. 1995) of oysters, Crassostrea virginica, that set on an artificial reef located in the Piankatank River, Virginia, in Augus...

  4. Unique parasite aDNA in moa coprolites from New Zealand suggests mass parasite extinctions followed human-induced megafauna extinctions

    Science.gov (United States)

    Lafferty, Kevin D.; Hopkins, Skylar R.

    2018-01-01

    Having split early from Gondwana, Zealandia (now modern New Zealand) escaped discovery until the late 13th century, and therefore remains an important glimpse into a human-free world. Without humans or other land mammals, diverse and peculiar birds evolved in isolation, including several flightless moa species, the giant pouakai eagle (Harpagornis moorei), the kiwi (Apteryx mantelli), and the kakapo parrot (Strigops habroptila). This unique community has fascinated paleoecologists, who have spent almost two centuries devising new ways to glean information from ancient bird remains. In PNAS, Boast et al. (1) apply one recent technological advance, ancient DNA (aDNA) metabarcoding, to confirm previous discoveries and report new details about moa and kakapo diets, parasites, and niches. Their efforts confirm Zealandia was a lot different before humans arrived.

  5. Research priorities for Chagas disease, human African trypanosomiasis and leishmaniasis.

    Science.gov (United States)

    2012-01-01

    This report provides a review and analysis of the research landscape for three diseases - Chagas disease, human African trypanosomiasis and leishmaniasis - that disproportionately afflict poor and remote populations with limited access to health services. It represents the work of the disease reference group on Chagas Disease, Human African Trypanosomiasis and Leishmaniasis (DRG3) which was established to identify key research priorities through review of research evidence and input from stakeholders' consultations. The diseases, which are caused by related protozoan parasites, are described in terms of their epidemiology and diseases burden, clinical forms and pathogenesis, HIV coinfection, diagnosis, drugs and drug resistance, vaccines, vector control, and health-care interventions. Priority areas for research are identified based on criteria such as public health relevance, benefit and impact on poor populations and equity, and feasibility. The priorities are found in the areas of diagnostics, drugs, vector control, asymptomatic infection, economic analysis of treatment and vector control methods, and in some specific issues such as surveillance methods or transmission-blocking vaccines for particular diseases. This report will be useful to researchers, policy and decision-makers, funding bodies, implementation organizations, and civil society. This is one of ten disease and thematic reference group reports that have come out of the TDR Think Tank, all of which have contributed to the development of the Global Report for Research on Infectious Diseases of Poverty, available at: www.who.int/tdr/stewardship/global_report/en/index.html.

  6. Vitamin B6-Dependent Enzymes in the Human Malaria Parasite Plasmodium falciparum: A Druggable Target?

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    Thales Kronenberger

    2014-01-01

    Full Text Available Malaria is a deadly infectious disease which affects millions of people each year in tropical regions. There is no effective vaccine available and the treatment is based on drugs which are currently facing an emergence of drug resistance and in this sense the search for new drug targets is indispensable. It is well established that vitamin biosynthetic pathways, such as the vitamin B6 de novo synthesis present in Plasmodium, are excellent drug targets. The active form of vitamin B6, pyridoxal 5-phosphate, is, besides its antioxidative properties, a cofactor for a variety of essential enzymes present in the malaria parasite which includes the ornithine decarboxylase (ODC, synthesis of polyamines, the aspartate aminotransferase (AspAT, involved in the protein biosynthesis, and the serine hydroxymethyltransferase (SHMT, a key enzyme within the folate metabolism.

  7. Proteins aggregation and human diseases

    International Nuclear Information System (INIS)

    Hu, Chin-Kun

    2015-01-01

    Many human diseases and the death of most supercentenarians are related to protein aggregation. Neurodegenerative diseases include Alzheimer's disease (AD), Huntington's disease (HD), Parkinson's disease (PD), frontotemporallobar degeneration, etc. Such diseases are due to progressive loss of structure or function of neurons caused by protein aggregation. For example, AD is considered to be related to aggregation of Aβ40 (peptide with 40 amino acids) and Aβ42 (peptide with 42 amino acids) and HD is considered to be related to aggregation of polyQ (polyglutamine) peptides. In this paper, we briefly review our recent discovery of key factors for protein aggregation. We used a lattice model to study the aggregation rates of proteins and found that the probability for a protein sequence to appear in the conformation of the aggregated state can be used to determine the temperature at which proteins can aggregate most quickly. We used molecular dynamics and simple models of polymer chains to study relaxation and aggregation of proteins under various conditions and found that when the bending-angle dependent and torsion-angle dependent interactions are zero or very small, then protein chains tend to aggregate at lower temperatures. All atom models were used to identify a key peptide chain for the aggregation of insulin chains and to find that two polyQ chains prefer anti-parallel conformation. It is pointed out that in many cases, protein aggregation does not result from protein mis-folding. A potential drug from Chinese medicine was found for Alzheimer's disease. (paper)

  8. Parasitic diseases as the cause of death of prisoners of war during the Korean War (1950-1953).

    Science.gov (United States)

    Huh, Sun

    2014-06-01

    To determine the cause of death of prisoners of war during the Korean War (1950-1953), death certificates or medical records were analyzed. Out of 7,614 deaths, 5,013 (65.8%) were due to infectious diseases. Although dysentery and tuberculosis were the most common infectious diseases, parasitic diseases had caused 14 deaths: paragonimiasis in 5, malaria in 3, amoebiasis in 2, intestinal parasitosis in 2, ascariasis in 1, and schistosomiasis in 1. These results showed that paragonimiasis, malaria, and amoebiasis were the most fatal parasitic diseases during the early 1950s in the Korean Peninsula. Since schistosomiasis is not endemic to Korea, it is likely that the infected private soldier moved from China or Japan to Korea.

  9. Monocyte-Derived Signals Activate Human Natural Killer Cells in Response to Leishmania Parasites

    Science.gov (United States)

    Messlinger, Helena; Sebald, Heidi; Heger, Lukas; Dudziak, Diana; Bogdan, Christian; Schleicher, Ulrike

    2018-01-01

    Activated natural killer (NK) cells release interferon (IFN)-γ, which is crucial for the control of intracellular pathogens such as Leishmania. In contrast to experimental murine leishmaniasis, the human NK cell response to Leishmania is still poorly characterized. Here, we investigated the interaction of human blood NK cells with promastigotes of different Leishmania species (Leishmania major, Leishmania mexicana, Leishmania infantum, and Leishmania donovani). When peripheral blood mononuclear cells or purified NK cells and monocytes (all derived from healthy blood donors from Germany without a history of leishmaniasis) were exposed to promastigotes, NK cells showed increased surface expression of the activation marker CD69. The extent of this effect varied depending on the Leishmania species; differences between dermotropic and viscerotropic L. infantum strains were not observed. Upregulation of CD69 required direct contact between monocytes and Leishmania and was partly inhibitable by anti-interleukin (IL)-18. Unexpectedly, IL-18 was undetectable in most of the supernatants (SNs) of monocyte/parasite cocultures. Confocal fluorescence microscopy of non-permeabilized cells revealed that Leishmania-infected monocytes trans-presented IL-18 to NK cells. Native, but not heat-treated SNs of monocyte/Leishmania cocultures also induced CD69 on NK cells, indicating the involvement of a soluble heat-labile factor other than IL-18. A role for the NK cell-activating cytokines IL-1β, IL-2, IL-12, IL-15, IL-21, and IFN-α/β was excluded. The increase of CD69 was not paralleled by NK cell IFN-γ production or enhanced cytotoxicity. However, prior exposure of NK cells to Leishmania parasites synergistically increased their IFN-γ release in response to IL-12, which was dependent on endogenous IL-18. CD1c+ dendritic cells were identified as possible source of Leishmania-induced IL-12. Finally, we observed that direct contact between Leishmania and NK cells reduced the

  10. Monocyte-Derived Signals Activate Human Natural Killer Cells in Response to Leishmania Parasites

    Directory of Open Access Journals (Sweden)

    Helena Messlinger

    2018-01-01

    Full Text Available Activated natural killer (NK cells release interferon (IFN-γ, which is crucial for the control of intracellular pathogens such as Leishmania. In contrast to experimental murine leishmaniasis, the human NK cell response to Leishmania is still poorly characterized. Here, we investigated the interaction of human blood NK cells with promastigotes of different Leishmania species (Leishmania major, Leishmania mexicana, Leishmania infantum, and Leishmania donovani. When peripheral blood mononuclear cells or purified NK cells and monocytes (all derived from healthy blood donors from Germany without a history of leishmaniasis were exposed to promastigotes, NK cells showed increased surface expression of the activation marker CD69. The extent of this effect varied depending on the Leishmania species; differences between dermotropic and viscerotropic L. infantum strains were not observed. Upregulation of CD69 required direct contact between monocytes and Leishmania and was partly inhibitable by anti-interleukin (IL-18. Unexpectedly, IL-18 was undetectable in most of the supernatants (SNs of monocyte/parasite cocultures. Confocal fluorescence microscopy of non-permeabilized cells revealed that Leishmania-infected monocytes trans-presented IL-18 to NK cells. Native, but not heat-treated SNs of monocyte/Leishmania cocultures also induced CD69 on NK cells, indicating the involvement of a soluble heat-labile factor other than IL-18. A role for the NK cell-activating cytokines IL-1β, IL-2, IL-12, IL-15, IL-21, and IFN-α/β was excluded. The increase of CD69 was not paralleled by NK cell IFN-γ production or enhanced cytotoxicity. However, prior exposure of NK cells to Leishmania parasites synergistically increased their IFN-γ release in response to IL-12, which was dependent on endogenous IL-18. CD1c+ dendritic cells were identified as possible source of Leishmania-induced IL-12. Finally, we observed that direct contact between Leishmania and NK cells

  11. Structure of a two-CAP-domain protein from the human hookworm parasite Necator americanus

    Energy Technology Data Exchange (ETDEWEB)

    Asojo, Oluwatoyin A., E-mail: oasojo@unmc.edu [Pathology and Microbiology Department, 986495 Nebraska Medical Center, Omaha, NE 68198-6495 (United States)

    2011-05-01

    The first structure of a two-CAP-domain protein, Na-ASP-1, from the major human hookworm parasite N. americanus refined to a resolution limit of 2.2 Å is presented. Major proteins secreted by the infective larval stage hookworms upon host entry include Ancylostoma secreted proteins (ASPs), which are characterized by one or two CAP (cysteine-rich secretory protein/antigen 5/pathogenesis related-1) domains. The CAP domain has been reported in diverse phylogenetically unrelated proteins, but has no confirmed function. The first structure of a two-CAP-domain protein, Na-ASP-1, from the major human hookworm parasite Necator americanus was refined to a resolution limit of 2.2 Å. The structure was solved by molecular replacement (MR) using Na-ASP-2, a one-CAP-domain ASP, as the search model. The correct MR solution could only be obtained by truncating the polyalanine model of Na-ASP-2 and removing several loops. The structure reveals two CAP domains linked by an extended loop. Overall, the carboxyl-terminal CAP domain is more similar to Na-ASP-2 than to the amino-terminal CAP domain. A large central cavity extends from the amino-terminal CAP domain to the carboxyl-terminal CAP domain, encompassing the putative CAP-binding cavity. The putative CAP-binding cavity is a characteristic cavity in the carboxyl-terminal CAP domain that contains a His and Glu pair. These residues are conserved in all single-CAP-domain proteins, but are absent in the amino-terminal CAP domain. The conserved His residues are oriented such that they appear to be capable of directly coordinating a zinc ion as observed for CAP proteins from reptile venoms. This first structure of a two-CAP-domain ASP can serve as a template for homology modeling of other two-CAP-domain proteins.

  12. Structure of a two-CAP-domain protein from the human hookworm parasite Necator americanus

    International Nuclear Information System (INIS)

    Asojo, Oluwatoyin A.

    2011-01-01

    The first structure of a two-CAP-domain protein, Na-ASP-1, from the major human hookworm parasite N. americanus refined to a resolution limit of 2.2 Å is presented. Major proteins secreted by the infective larval stage hookworms upon host entry include Ancylostoma secreted proteins (ASPs), which are characterized by one or two CAP (cysteine-rich secretory protein/antigen 5/pathogenesis related-1) domains. The CAP domain has been reported in diverse phylogenetically unrelated proteins, but has no confirmed function. The first structure of a two-CAP-domain protein, Na-ASP-1, from the major human hookworm parasite Necator americanus was refined to a resolution limit of 2.2 Å. The structure was solved by molecular replacement (MR) using Na-ASP-2, a one-CAP-domain ASP, as the search model. The correct MR solution could only be obtained by truncating the polyalanine model of Na-ASP-2 and removing several loops. The structure reveals two CAP domains linked by an extended loop. Overall, the carboxyl-terminal CAP domain is more similar to Na-ASP-2 than to the amino-terminal CAP domain. A large central cavity extends from the amino-terminal CAP domain to the carboxyl-terminal CAP domain, encompassing the putative CAP-binding cavity. The putative CAP-binding cavity is a characteristic cavity in the carboxyl-terminal CAP domain that contains a His and Glu pair. These residues are conserved in all single-CAP-domain proteins, but are absent in the amino-terminal CAP domain. The conserved His residues are oriented such that they appear to be capable of directly coordinating a zinc ion as observed for CAP proteins from reptile venoms. This first structure of a two-CAP-domain ASP can serve as a template for homology modeling of other two-CAP-domain proteins

  13. Immunodiagnosis of parasitic infections using nuclear techniques

    International Nuclear Information System (INIS)

    1985-07-01

    This report documents the recommendations of the ''Advisory Group on Immunodiagnosis of Parasitic Infections Using Nuclear Techniques'' with a focus on malaria, schistosomiasis and filariasis. Radionuclide tracers are considered an important component of present and future immunological methods for the assessment of the host's humoral and cellular immunity to the parasite and the detection of parasite antigen(s) in human body fluids. The Advisory Group has concluded that there is a continuing need for the development and application of immunodiagnostic methods in parasitic diseases. This report concerns methods which are currently or potentially applicable to immunodiagnostic investigations in parasitic diseases. Reference is made, where appropriate, to recent developments in research which may lead to improvement and standardization of methods now available and the development of new methodology. Separate abstracts on various papers presented were prepared

  14. Comparison between Two Decades of Prevalence of Intestinal Parasitic Diseases and Risk Factors in a Brazilian Urban Centre

    Directory of Open Access Journals (Sweden)

    Maria Aparecida Alves de Oliveira Serra

    2015-01-01

    Full Text Available Objectives. This study’s objective was to compare the prevalence of intestinal parasites and associated risk factors in children in urban communities, in the Brazilian Northeast, between two decades. Methods. This quantitative transversal study consisted of a comparative analysis of two different samples: the first viewing the years 1992–1996 and the other through a coproepidemiological data survey undertaken in 2010-2011. Results. It was evidenced that there was a reduction of intestinal parasites and that there were improvements in the socioenvironmental conditions between the two decades evaluated. It was observed that, in the period 1992–1996, playing out in the streets was associated with a higher risk for acquiring intestinal parasites. Over the 2010-2011 period, the characteristics of more than five residents per household, houses with dirt floors, children who live in homes without piped water, and children who play out in the streets were associated with a higher risk of intestinal parasitic infection. Conclusion. The study showed a reduction of intestinal parasitic diseases to 23.8% in 2010-2011 from 81.3% in 1992–1996 and improvement of the social-sanitary conditions of the population between the decades analyzed.

  15. Mechanisms of cellular invasion by intracellular parasites.

    Science.gov (United States)

    Walker, Dawn M; Oghumu, Steve; Gupta, Gaurav; McGwire, Bradford S; Drew, Mark E; Satoskar, Abhay R

    2014-04-01

    Numerous disease-causing parasites must invade host cells in order to prosper. Collectively, such pathogens are responsible for a staggering amount of human sickness and death throughout the world. Leishmaniasis, Chagas disease, toxoplasmosis, and malaria are neglected diseases and therefore are linked to socio-economical and geographical factors, affecting well-over half the world's population. Such obligate intracellular parasites have co-evolved with humans to establish a complexity of specific molecular parasite-host cell interactions, forming the basis of the parasite's cellular tropism. They make use of such interactions to invade host cells as a means to migrate through various tissues, to evade the host immune system, and to undergo intracellular replication. These cellular migration and invasion events are absolutely essential for the completion of the lifecycles of these parasites and lead to their for disease pathogenesis. This review is an overview of the molecular mechanisms of protozoan parasite invasion of host cells and discussion of therapeutic strategies, which could be developed by targeting these invasion pathways. Specifically, we focus on four species of protozoan parasites Leishmania, Trypanosoma cruzi, Plasmodium, and Toxoplasma, which are responsible for significant morbidity and mortality.

  16. Parasites and malignancies, a review, with emphasis on digestive cancer induced by Cryptosporidium parvum (Alveolata: Apicomplexa)

    OpenAIRE

    Benamrouz S.; Conseil V.; Creusy C.; Calderon E.; Dei-Cas E.; Certad G.

    2012-01-01

    The International Agency for Research on Cancer (IARC) identifies ten infectious agents (viruses, bacteria, parasites) able to induce cancer disease in humans. Among parasites, a carcinogenic role is currently recognized to the digenetic trematodes Schistosoma haematobium, leading to bladder cancer, and to Clonorchis sinensis or Opisthorchis viverrini, which cause cholangiocarcinoma. Furthermore, several reports suspected the potential association of other parasitic infections (due to Protozo...

  17. Ecomorphology and disease: cryptic effects of parasitism on host habitat use, thermoregulation, and predator avoidance.

    Science.gov (United States)

    Goodman, Brett A; Johnson, Pieter T J

    2011-03-01

    Parasites can cause dramatic changes in the phenotypes of their hosts, sometimes leading to a higher probability of predation and parasite transmission. Because an organism's morphology directly affects its locomotion, even subtle changes in key morphological traits may affect survival and behavior. However, despite the ubiquity of parasites in natural communities, few studies have incorporated parasites into ecomorphological research. Here, we evaluated the effects of parasite-induced changes in host phenotype on the habitat use, thermal biology, and simulated predator-escape ability of Pacific chorus frogs (Pseudacris regilla) in natural environments. Frogs with parasite-induced limb malformations were more likely to use ground microhabitats relative to vertical refugia and selected less-angled perches closer to the ground in comparison with normal frogs. Although both groups had similar levels of infection, malformed frogs used warmer microhabitats, which resulted in higher body temperatures. Likely as a result of their morphological abnormalities, malformed frogs allowed a simulated predator to approach closer before escaping and escaped shorter distances relative to normal frogs. These data indicate that parasite-induced morphological changes can significantly alter host behavior and habitat use, highlighting the importance of incorporating the ubiquitous, albeit cryptic, role of parasites into ecomorphological research.

  18. Draft genome of neurotropic nematode parasite Angiostrongylus cantonensis, causative agent of human eosinophilic meningitis.

    Science.gov (United States)

    Yong, Hoi-Sen; Eamsobhana, Praphathip; Lim, Phaik-Eem; Razali, Rozaimi; Aziz, Farhanah Abdul; Rosli, Nurul Shielawati Mohamed; Poole-Johnson, Johan; Anwar, Arif

    2015-08-01

    Angiostrongylus cantonensis is a bursate nematode parasite that causes eosinophilic meningitis (or meningoencephalitis) in humans in many parts of the world. The genomic data from A. cantonensis will form a useful resource for comparative genomic and chemogenomic studies to aid the development of diagnostics and therapeutics. We have sequenced, assembled and annotated the genome of A. cantonensis. The genome size is estimated to be ∼260 Mb, with 17,280 genomic scaffolds, 91X coverage, 81.45% for complete and 93.95% for partial score based on CEGMA analysis of genome completeness. The number of predicted genes of ≥300 bp was 17,482. A total of 7737 predicted protein-coding genes of ≥50 amino acids were identified in the assembled genome. Among the proteins of known function, kinases are the most abundant followed by transferases. The draft genome contains 34 excretory-secretory proteins (ES), a minimum of 44 Nematode Astacin (NAS) metalloproteases, 12 Homeobox (HOX) genes, and 30 neurotransmitters. The assembled genome size (260 Mb) is larger than those of Pristionchus pacificus, Caenorhabditis elegans, Necator americanus, Caenorhabditis briggsae, Trichinella spiralis, Brugia malayi and Loa loa, but smaller than Haemonchus contortus and Ascaris suum. The repeat content (25%) is similar to H. contortus. The GC content (41.17%) is lower compared to P. pacificus (42.7%) and H. contortus (43.1%) but higher compared to C. briggsae (37.69%), A. suum (37.9%) and N. americanus (40.2%) while the scaffold N50 is 42,191. This draft genome will facilitate the understanding of many unresolved issues on the parasite and the disorder it causes. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Gastrointestinal helminth parasites of pet and stray dogs as a potential risk for human health in Bahir Dar town, north-western Ethiopia

    Directory of Open Access Journals (Sweden)

    Tadiwos Abere

    Full Text Available Aim: A cross-sectional study was carried out from November 2011 to April 2012 to determine the prevalence and species of gastrointestinal (GI helminth parasites in pet and stray dogs as a potential risk for human health in Bahir Dar town, northwestern Ethiopia. Materials and Methods: A total of 384 and 46 faecal samples were collected from pet and stray dogs, respectively and xamined by using standard coprologic techniques. Results: The overall prevalence of GI helminth infection in pet and stray dogs was 75.26 and 84.78%, respectively. The detected parasites with their frequencies in pet dogs were Ancylostoma caninum (78.89%, Toxocara canis (39.79%, Dipylidium caninum (29.75%, Strongyloides stercoralis (29.06%, Taeniidae (23.87% and Trichuris vulpis (7.95%. Stray dogs were found more likely to be polyparasitized and presented higher prevalence of A. caninum, T. canis, S. stercoralis, Trichuris vulpis and Taeniidae (P < 0.05 than domiciled ones. Diphyllobothrium latum was detected only in 10.25% of stray dogs. Toxocara canis and A. caninum (P < 0.05 were detected more frequently in dogs with less than 6 months of age (P <0.05 than old age dogs. The sex or breed groups didn't significantly affect the prevalence of parasites. A significant variation was recorded (P < 0.05 between different feeding systems where higher prevalence was observed in uncontrolled feeding group (82.18% compared to controlled feeding (32.08%. Conclusion: Different gastrointestinal parasites in pet and stray dogs were identified in the study area that can potentially infect humans and cause serious public-health problems. Thus, concerted efforts should therefore be made to educate dog owners to embrace modern dog disease control programs and measures have to be taken on stray dogs. [Vet World 2013; 6(7.000: 388-392

  20. A novel PCR-based system for the detection of four species of human malaria parasites and Plasmodium knowlesi

    Science.gov (United States)

    Komaki-Yasuda, Kanako; Vincent, Jeanne Perpétue; Nakatsu, Masami; Kato, Yasuyuki; Ohmagari, Norio

    2018-01-01

    A microscopy-based diagnosis is the gold standard for the detection and identification of malaria parasites in a patient’s blood. However, the detection of cases involving a low number of parasites and the differentiation of species sometimes requires a skilled microscopist. Although PCR-based diagnostic methods are already known to be very powerful tools, the time required to apply such methods is still much longer in comparison to traditional microscopic observation. Thus, improvements to PCR systems are sought to facilitate the more rapid and accurate detection of human malaria parasites Plasmodium falciparum, P. vivax, P. ovale, and P. malariae, as well as P. knowlesi, which is a simian malaria parasite that is currently widely distributed in Southeast Asia. A nested PCR that targets the small subunit ribosomal RNA genes of malaria parasites was performed using a “fast PCR enzyme”. In the first PCR, universal primers for all parasite species were used. In the second PCR, inner-specific primers, which targeted sequences from P. falciparum, P. vivax, P. ovale, P. malariae, and P. knowlesi, were used. The PCR reaction time was reduced with the use of the “fast PCR enzyme”, with only 65 minutes required to perform the first and second PCRs. The specific primers only reacted with the sequences of their targeted parasite species and never cross-reacted with sequences from other species under the defined PCR conditions. The diagnoses of 36 clinical samples that were obtained using this new PCR system were highly consistent with the microscopic diagnoses. PMID:29370297

  1. Doenças parasitárias em ruminantes no semi-árido brasileiro Parasitic diseases in ruminants in the Brazilian semiarid

    Directory of Open Access Journals (Sweden)

    Valéria Medeiros de M. Costa

    2009-07-01

    -árido o Rhipicephalus (Boophilus microplus não sobrevive durante o período de seca, mas, tristeza parasitária pode ocorrer quando no início do período chuvoso bovinos com carrapatos são introduzidos e esses se multiplicam durante o mesmo.Clinical cases and diagnostic specimens from ruminants received by the Veterinary Hospital of the University of Campina Grande in Patos, Paraíba, Brazil, from January 2000 to August 2007, were reviewed to evaluate some epidemiological aspects of parasitic diseases of ruminants in the semiarid region of Paraíba and neighboring states. The region has an annual rainfall of about 800mm, with irregular rains concentrated in a 3 to 4-month-period, and an average annual temperature of 26°C. During those years, 163 (5.31% out of 3,064 ruminants were affected by some parasitic disease. The most important parasitosis in goats and sheep was gastrointestinal helminthiasis, mainly hemonchosis; goats were more affected (6.24% of cases in this species than sheep (4.7% of cases. The higher frequency of the disease in goats may be associated with higher susceptibility or due to treatment mistakes, i.e. use of the same dose for both species, which for most anti-antihelmintics is insufficient for goats. Cattle have a low rate of gastrointestinal helminthiasis (1 out of 1,113 cases. This low frequency is probably due to the farming system in the semiarid, with low stocking rate, up to one adult bovine for every 13-16 ha, and permanence of calves (susceptible with their mothers (resistant for nearly one year before weaning. The occurrence of eimeriosis in goats and sheep was observed in 0.76% of the cases, involving only young animals. The main cattle disease was tick fever with 14 outbreaks. Outbreaks of tick fever occur, mainly at the end of the raining season in areas of the semiarid which are marginal for tick, like plateaus and mountains of the Borborema region, irrigated areas, and areas of the basins of two rivers of the region. In the drier

  2. Leveraging rural energy investment for parasitic disease control: schistosome ova inactivation and energy co-benefits of anaerobic digesters in rural China.

    Directory of Open Access Journals (Sweden)

    Justin Remais

    Full Text Available Cooking and heating remain the most energy intensive activities among the world's poor, and thus improved access to clean energies for these tasks has been highlighted as a key requirement of attaining the major objectives of the UN Millennium Development Goals. A move towards clean energy technologies such as biogas systems (which produce methane from human and animal waste has the potential to provide immediate benefits for the control of neglected tropical diseases. Here, an assessment of the parasitic disease and energy benefits of biogas systems in Sichuan Province, China, is presented, highlighting how the public health sector can leverage the proliferation of rural energy projects for infectious disease control.First, the effectiveness of biogas systems at inactivating and removing ova of the human parasite Schistosoma japonicum is experimentally evaluated. Second, the impact of biogas infrastructure on energy use and environmental quality as reported by surveyed village populations is assessed, as is the community acceptance of the technology. No viable eggs were recovered in the effluent collected weekly from biogas systems for two months following seeding with infected stool. Less than 1% of ova were recovered viable from a series of nylon bags seeded with ova, a 2-log removal attributable to biochemical inactivation. More than 90% of Ascaris lumbricoides ova (used as a proxy for S. japonicum ova counted at the influent of two biogas systems were removed in the systems when adjusted for system residence time, an approximate 1-log removal attributable to sedimentation. Combined, these inactivation/removal processes underscore the promise of biogas infrastructure for reducing parasite contamination resulting from nightsoil use. When interviewed an average of 4 years after construction, villagers attributed large changes in fuel usage to the installation of biogas systems. Household coal usage decreased by 68%, wood by 74%, and crop waste

  3. Non-biting cyclorrhaphan flies (Diptera) as carriers of intestinal human parasites in slum areas of Addis Ababa, Ethiopia.

    Science.gov (United States)

    Getachew, Sisay; Gebre-Michael, Teshome; Erko, Berhanu; Balkew, Meshesha; Medhin, Girmay

    2007-09-01

    A study was conducted to determine the role of non-biting cyclorrhaphan flies as carriers of intestinal parasites in slum areas of Addis Ababa from January 2004 to June 2004. A total of 9550 flies, comprising of at least seven species were collected from four selected sites and examined for human intestinal parasites using the formol-ether concentration method. The dominant fly species was Chrysomya rufifacies (34.9%) followed by Musca domestica (31%), Musca sorbens (20.5.%), Lucina cuprina (6.8%), Sarcophaga sp. (2.8%), Calliphora vicina (2.2%) and Wohlfahrtia sp. (1.8%). Six intestinal helminths (Ascaris lumbricoides, Trichuris trichiura, hookworms, Hymenolepis nana, Taenia spp. and Strongyloides stercoralis) and at least four protozoan parasites (Entamoeba histolytica/dispar, Entamoeba coli, Giardia lamblia and Cryptosporidium sp.) were isolated from both the external and gut contents of the flies. A. lumbricoides and T. trichiura among the helminths and E. histolytica/dispar and E. coli among the protozoans were the dominant parasites detected both on the external and in the gut contents of the flies, but occurring more in the latter. Among the flies, C. rufifacies and M. sorbens were the highest carriers of the helminth and protozoan parasites, respectively. The public health significance of these findings is highlighted.

  4. Getting to the guts of the matter: the status and potential of 'omics' research of parasitic protists of the human gastrointestinal system.

    Science.gov (United States)

    Jex, Aaron R; Koehler, Anson V; Ansell, Brendan R; Baker, Louise; Karunajeewa, Harin; Gasser, Robin B

    2013-11-01

    Parasitic protists are a major cause of diarrhoeal illnesses in humans globally. Collectively, enteric pathogens exceed all other forms of infectious disease, in terms of their estimated global prevalence and socioeconomic impact. They have a disproportionately high impact on children in impoverished communities, leading to acute (diarrhoea, vomiting, dehydration and death) and chronic disease (malabsorption, malnutrition, physical and cognitive stunting and predisposition to chronic, non-communicable disease) consequences. However, historically, investment in research and disease control measures has been disproportionately poor, leading to their current classification as neglected pathogens. A sound understanding of their biology is essential in underpinning detection, treatment and control efforts. One major tool in rapidly improving our knowledge of these parasites is the use of biological systems, including 'omic' technologies. In recent years, these tools have shown significant success when applied to enteric protists. This review summarises much of this knowledge and highlights the significant remaining knowledge gaps. A major focus of the present review was to provide a perspective on a way forward to address these gaps using advanced biotechnologies. Copyright © 2013 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  5. Intestinal parasitic infections, cysticercosis and hydatic diseases Parasitosis intestinales, cisticercosis e hidatidosis

    Directory of Open Access Journals (Sweden)

    David Botero

    1990-03-01

    Full Text Available

    This paper offers an up to date review of the intestinal parasitic infections, cysticercosis and hydatic disease found In Colombia. Their main epidemiological, clinical, preventive and therapeutic features are presented, to provide the reader with a current view of their public health Importance, prevalence and impact on morbidity and mortality.

    Se presenta una revisión actualizada sobre las parasitosis intestinales, la cisticercosis y la hidatidosis en Colombia, con una breve descripción de la prevalencia, las características epidemiológicas, los efectos sobre la salud y algunos aspectos de control y tratamiento. Con esta revisión se busca tener información resumida sobre las parasitosis que se encuentran en Colombia y su mayor o menor Importancia en salud pública. TambIén se pretende ofrecer una Idea del nivel de gravedad de estas entidades como causas de morbilidad y mortalidad en este país. 

  6. DNA typing of ancient parasite eggs from environmental samples identifies human and animal worm infections in Viking-age settlement.

    Science.gov (United States)

    Søe, Martin Jensen; Nejsum, Peter; Fredensborg, Brian Lund; Kapel, Christian Moliin Outzen

    2015-02-01

    Ancient parasite eggs were recovered from environmental samples collected at a Viking-age settlement in Viborg, Denmark, dated 1018-1030 A.D. Morphological examination identified Ascaris sp., Trichuris sp., and Fasciola sp. eggs, but size and shape did not allow species identification. By carefully selecting genetic markers, PCR amplification and sequencing of ancient DNA (aDNA) isolates resulted in identification of: the human whipworm, Trichuris trichiura , using SSUrRNA sequence homology; Ascaris sp. with 100% homology to cox1 haplotype 07; and Fasciola hepatica using ITS1 sequence homology. The identification of T. trichiura eggs indicates that human fecal material is present and, hence, that the Ascaris sp. haplotype 07 was most likely a human variant in Viking-age Denmark. The location of the F. hepatica finding suggests that sheep or cattle are the most likely hosts. Further, we sequenced the Ascaris sp. 18S rRNA gene in recent isolates from humans and pigs of global distribution and show that this is not a suited marker for species-specific identification. Finally, we discuss ancient parasitism in Denmark and the implementation of aDNA analysis methods in paleoparasitological studies. We argue that when employing species-specific identification, soil samples offer excellent opportunities for studies of human parasite infections and of human and animal interactions of the past.

  7. Cryo-EM structures of the 80S ribosomes from human parasites Trichomonas vaginalis and Toxoplasma gondii

    Institute of Scientific and Technical Information of China (English)

    Zhifei Li; Qiang Guo; Lvqin Zheng; Yongsheng Ji; Yi-Ting Xie; De-Hua Lai; Zhao-Rong Lun; Xun Suo; Ning Gao

    2017-01-01

    As an indispensable molecular machine universal in all living organisms,the ribosome has been selected by evolution to be the natural target of many antibiotics and small-molecule inhibitors.High-resolution structures of pathogen ribosomes are crucial for understanding the general and unique aspects of translation control in disease-causing microbes.With cryo-electron microscopy technique,we have determined structures of the cytosolic ribosomes from two human parasites,Trichomonas vaginalis and Toxoplasma gondii,at resolution of 3.2-3.4,(A).Although the ribosomal proteins from both pathogens are typical members of eukaryotic families,with a co-evolution pattern between certain species-specific insertions/extensions and neighboring ribosomal RNA (rRNA) expansion segments,the sizes of their rRNAs are sharply different.Very interestingly,rRNAs of T.vaginalis are in size comparable to prokaryotic counterparts,with nearly all the eukaryote-specific rRNA expansion segments missing.These structures facilitate the dissection of evolution path for ribosomal proteins and RNAs,and may aid in design of novel translation inhibitors.

  8. Mechanisms of host seeking by parasitic nematodes.

    Science.gov (United States)

    Gang, Spencer S; Hallem, Elissa A

    2016-07-01

    The phylum Nematoda comprises a diverse group of roundworms that includes parasites of vertebrates, invertebrates, and plants. Human-parasitic nematodes infect more than one billion people worldwide and cause some of the most common neglected tropical diseases, particularly in low-resource countries [1]. Parasitic nematodes of livestock and crops result in billions of dollars in losses each year [1]. Many nematode infections are treatable with low-cost anthelmintic drugs, but repeated infections are common in endemic areas and drug resistance is a growing concern with increasing therapeutic and agricultural administration [1]. Many parasitic nematodes have an environmental infective larval stage that engages in host seeking, a process whereby the infective larvae use sensory cues to search for hosts. Host seeking is a complex behavior that involves multiple sensory modalities, including olfaction, gustation, thermosensation, and humidity sensation. As the initial step of the parasite-host interaction, host seeking could be a powerful target for preventative intervention. However, host-seeking behavior remains poorly understood. Here we review what is currently known about the host-seeking behaviors of different parasitic nematodes, including insect-parasitic nematodes, mammalian-parasitic nematodes, and plant-parasitic nematodes. We also discuss the neural bases of these behaviors. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Parasites, diseases, and health status of sympatric populations of sika deer and white-tailed deer in Maryland and Virginia.

    Science.gov (United States)

    Davidson, W R; Crow, C B

    1983-10-01

    In July 1981, investigations on parasites, diseases, and herd health status were conducted on sympatric populations of sika deer (Cervus nippon) and white-tailed deer (Odocoileus virginianus) from Blackwater National Wildlife Refuge (Maryland) and Chincoteague National Wildlife Refuge (Virginia) on the Delmarva Peninsula. Five adult deer of each species were collected from each location and subjected to thorough necropsy examinations and laboratory tests. White-tailed deer at both locations harbored protozoan, helminth, and arthropod parasites typically associated with this species throughout the southeastern United States. In contrast, sika deer at both locations harbored only light burdens of ticks, chiggers, and sarcocysts. Serologic tests for antibodies to seven infectious disease agents revealed evidence of exposure to bovine virus diarrhea (BVD) virus, infectious bovine rhinotracheitis virus, and parainfluenza3 virus in white-tailed deer, but only BVD virus in sika deer. At both locations the general health status of sika deer was superior to that of white-tailed deer.

  10. Tight junctions and human diseases.

    Science.gov (United States)

    Sawada, Norimasa; Murata, Masaki; Kikuchi, Keisuke; Osanai, Makoto; Tobioka, Hirotoshi; Kojima, Takashi; Chiba, Hideki

    2003-09-01

    Tight junctions are intercellular junctions adjacent to the apical end of the lateral membrane surface. They have two functions, the barrier (or gate) function and the fence function. The barrier function of tight junctions regulates the passage of ions, water, and various macromolecules, even of cancer cells, through paracellular spaces. The barrier function is thus relevant to edema, jaundice, diarrhea, and blood-borne metastasis. On the other hand, the fence function maintains cell polarity. In other words, tight junctions work as a fence to prevent intermixing of molecules in the apical membrane with those in the lateral membrane. This function is deeply involved in cancer cell biology, in terms of loss of cell polarity. Of the proteins comprising tight junctions, integral membrane proteins occludin, claudins, and JAMs have been recently discovered. Of these molecules, claudins are exclusively responsible for the formation of tight-junction strands and are connected with the actin cytoskeleton mediated by ZO-1. Thus, both functions of tight junctions are dependent on the integrity of the actin cytoskeleton as well as ATP. Mutations in the claudin14 and the claudin16 genes result in hereditary deafness and hereditary hypomagnesemia, respectively. Some pathogenic bacteria and viruses target and affect the tight-junction function, leading to diseases. In this review, the relationship between tight junctions and human diseases is summarized.

  11. Influence of Multiple Infection and Relatedness on Virulence: Disease Dynamics in an Experimental Plant Population and Its Castrating Parasite

    Science.gov (United States)

    Buono, Lorenza; López-Villavicencio, Manuela; Shykoff, Jacqui A.; Snirc, Alodie; Giraud, Tatiana

    2014-01-01

    The level of parasite virulence, i.e., the decrease in host's fitness due to a pathogen, is expected to depend on several parameters, such as the type of the disease (e.g., castrating or host-killing) and the prevalence of multiple infections. Although these parameters have been extensively studied theoretically, few empirical data are available to validate theoretical predictions. Using the anther smut castrating disease on Silene latifolia caused by Microbotryum lychnidis-dioicae, we studied the dynamics of multiple infections and of different components of virulence (host death, non-recovery and percentage of castrated stems) during the entire lifespan of the host in an experimental population. We monitored the number of fungal genotypes within plants and their relatedness across five years, using microsatellite markers, as well as the rates of recovery and host death in the population. The mean relatedness among genotypes within plants remained at a high level throughout the entire host lifespan despite the dynamics of the disease, with recurrent new infections. Recovery was lower for plants with multiple infections compared to plants infected by a single genotype. As expected for castrating parasites, M. lychnidis-dioicae did not increase host mortality. Mortality varied across years but was generally lower for plants that had been diseased the preceding year. This is one of the few studies to have empirically verified theoretical expectations for castrating parasites, and to show particularly i) that castrated hosts live longer, suggesting that parasites can redirect resources normally used in reproduction to increase host lifespan, lengthening their transmission phase, and ii) that multiple infections increase virulence, here in terms of non-recovery and host castration. PMID:24892951

  12. Parasitic nematode interactions with mammals and plants.

    Science.gov (United States)

    Jasmer, Douglas P; Goverse, Aska; Smant, Geert

    2003-01-01

    Parasitic nematodes that infect humans, animals, and plants cause serious diseases that are deleterious to human health and agricultural productivity. Chemical and biological control methods have reduced the impact of these parasites. However, surviving environmental stages lead to persistent reinfection of host species. In addition, development of resistance to nematicides and anthelmintics by these parasites and reduced availability of some nematicides, for environmental protection, pose significant obstacles for current and future prospects of effective parasite control. Due to marked differences in host species, research on animal and plant parasitic nematodes often proceeds independently. Despite the differences between animals and plants, basic cellular properties are shared among these host organisms. Some common properties may be important for mechanisms [homologous or convergent (homoplastic)] by which nematodes successfully infect these diverse hosts or by which animal and plant hosts resist infections by these pathogens. Here we compare host/parasite interactions between plant parasitic nematodes (PPN) and animal parasitic nematodes, with an emphasis on mammalian hosts (MPN). Similarities and differences are considered in the context of progress on molecular dissection of these interactions. A comprehensive coverage is not possible in the space allotted. Instead, an illustrative approach is used to establish examples that, it is hoped, exemplify the value of the comparative approach.

  13. Associations between common intestinal parasites and bacteria in humans as revealed by qPCR

    DEFF Research Database (Denmark)

    O'Brien Andersen, L.; Karim, A. B.; Roager, Henrik Munch

    2016-01-01

    Several studies have shown associations between groups of intestinal bacterial or specific ratios between bacterial groups and various disease traits. Meanwhile, little is known about interactions and associations between eukaryotic and prokaryotic microorganisms in the human gut. In this work, we...

  14. Trickle or clumped infection process? An analysis of aggregation in the weights of the parasitic roundworm of humans, Ascaris lumbricoides.

    Science.gov (United States)

    Walker, Martin; Hall, Andrew; Basáñez, María-Gloria

    2010-10-01

    Studying the distribution of parasitic helminth body size across a population of definitive hosts can advance our understanding of parasite population biology. Body size is typically correlated with egg production. Consequently, inequalities in body size have been frequently measured to infer variation in reproductive success (VRS). Body size is also related to parasite age (time since entering the definitive host) and potentially provides valuable information on the mode of acquisition and establishment of immature (larval) parasites within the host: whether parasites tend to establish singly or in aggregates. The mode of acquisition of soil-transmitted helminths has been a theoretical consideration in the parasitological literature but has eluded data-driven investigation. In this paper, we analyse individual Ascaris lumbricoides weight data collected from a cohort of human hosts before and after re-infection following curative treatment, and explore its distribution within and among individuals in the population. Lorenz curves and Gini coefficients indicate that levels of weight inequality (a proxy for VRS) in A.lumbricoides are lower than other published estimates from animal-helminth systems. We explore levels of intra-host weight aggregation using statistical models to estimate the intraclass correlation coefficient (ICC) while adjusting for covariates using a flexible fractional polynomial transformation approach capable of handling non-linear functional relationships. The estimated ICCs indicate that weights are aggregated within hosts both at equilibrium and after re-infection, suggesting that parasites may establish within the host in clumps. The implications of a clumped infection process are discussed in terms of ascariasis transmission dynamics, control and anthelmintic resistance. Copyright © 2010 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  15. Defining the relationship between Plasmodium falciparum parasite rate and clinical disease: statistical models for disease burden estimation

    Directory of Open Access Journals (Sweden)

    Snow Robert W

    2009-08-01

    Full Text Available Abstract Background Clinical malaria has proven an elusive burden to enumerate. Many cases go undetected by routine disease recording systems. Epidemiologists have, therefore, frequently defaulted to actively measuring malaria in population cohorts through time. Measuring the clinical incidence of malaria longitudinally is labour-intensive and impossible to undertake universally. There is a need, therefore, to define a relationship between clinical incidence and the easier and more commonly measured index of infection prevalence: the "parasite rate". This relationship can help provide an informed basis to define malaria burdens in areas where health statistics are inadequate. Methods Formal literature searches were conducted for Plasmodium falciparum malaria incidence surveys undertaken prospectively through active case detection at least every 14 days. The data were abstracted, standardized and geo-referenced. Incidence surveys were time-space matched with modelled estimates of infection prevalence derived from a larger database of parasite prevalence surveys and modelling procedures developed for a global malaria endemicity map. Several potential relationships between clinical incidence and infection prevalence were then specified in a non-parametric Gaussian process model with minimal, biologically informed, prior constraints. Bayesian inference was then used to choose between the candidate models. Results The suggested relationships with credible intervals are shown for the Africa and a combined America and Central and South East Asia regions. In both regions clinical incidence increased slowly and smoothly as a function of infection prevalence. In Africa, when infection prevalence exceeded 40%, clinical incidence reached a plateau of 500 cases per thousand of the population per annum. In the combined America and Central and South East Asia regions, this plateau was reached at 250 cases per thousand of the population per annum. A temporal

  16. Functions of myosin motors tailored for parasitism

    DEFF Research Database (Denmark)

    Mueller, Christina; Graindorge, Arnault; Soldati-Favre, Dominique

    2017-01-01

    Myosin motors are one of the largest protein families in eukaryotes that exhibit divergent cellular functions. Their roles in protozoans, a diverse group of anciently diverged, single celled organisms with many prominent members known to be parasitic and to cause diseases in human and livestock......, are largely unknown. In the recent years many different approaches, among them whole genome sequencing, phylogenetic analyses and functional studies have increased our understanding on the distribution, protein architecture and function of unconventional myosin motors in protozoan parasites. In Apicomplexa......, myosins turn out to be highly specialized and to exhibit unique functions tailored to accommodate the lifestyle of these parasites....

  17. Neglected Parasitic Infections: Toxocariasis

    Centers for Disease Control (CDC) Podcasts

    2012-01-05

    This podcast is an overview of the Clinician Outreach and Communication Activity (COCA) Call: Neglected Parasitic Infections in the United States. Neglected Parasitic Infections are a group of diseases that afflict vulnerable populations and are often not well studied or diagnosed. A subject matter expert from CDC's Division of Parasitic Diseases and Malaria describes the epidemiology, diagnosis, and treatment of toxocariasis.  Created: 1/5/2012 by Center for Global Health, Division of Parasitic Diseases and Malaria (DPDM); Emergency Risk Communication Branch (ERCB)/Joint Information Center (JIC), Office of Public Health Preparedness and Response (OPHPR).   Date Released: 1/9/2012.

  18. Crystallization and preliminary X-ray analysis of Na-SAA-2 from the human hookworm parasite Necator americanus

    International Nuclear Information System (INIS)

    Asojo, Oluwatoyin A.; Goud, Gaddam N.; Zhan, Bin; Ordonez, Katherine; Sedlacek, Meghan; Homma, Kohei; Deumic, Vehid; Gupta, Richi; Brelsford, Jill; Price, Merelyn K.; Ngamelue, Michelle N.; Hotez, Peter J.

    2010-01-01

    The purification, crystallization and preliminary X-ray diffraction analysis of a surface-associated antigen from the major human hookworm N. americanus is presented. Human hookworms are among the most pathogenic soil-transmitted helminths. These parasitic nematodes have co-evolved with the host and are able to maintain a high worm burden for decades without killing the human host. However, it is possible to develop vaccines against laboratory-challenge hookworm infections using either irradiated third-state infective larvae (L3) or enzymes from the adult parasites. In an effort to control hookworm infection globally, the Human Hookworm Vaccine Initiative, a product-development partnership with the Sabin Vaccine Institute to develop new control tools including vaccines, has identified a battery of protein antigens, including surface-associated antigens (SAAs) from L3. SAA proteins are characterized by a 13 kDa conserved domain of unknown function. SAA proteins are found on the surface of infective L3 stages (and some adult stages) of different nematode parasites, suggesting that they may play important roles in these organisms. The atomic structures and function of SAA proteins remain undetermined and in an effort to remedy this situation recombinant Na-SAA-2 from the most prevalent human hookworm parasite Necator americanus has been expressed, purified and crystallized. Useful X-ray data have been collected to 2.3 Å resolution from a crystal that belonged to the monoclinic space group C2 with unit-cell parameters a = 73.88, b = 35.58, c = 42.75 Å, β = 116.1°

  19. Trickle or clumped infection process? A stochastic model for the infection process of the parasitic roundworm of humans, Ascaris lumbricoides.

    Science.gov (United States)

    Walker, Martin; Hall, Andrew; Basáñez, María-Gloria

    2010-10-01

    The importance of the mode of acquisition of infectious stages of directly-transmitted parasitic helminths has been acknowledged in population dynamics models; hosts may acquire eggs/larvae singly in a "trickle" type manner or in "clumps". Such models have shown that the mode of acquisition influences the distribution and dynamics of parasite loads, the stability of host-parasite systems and the rate of emergence of anthelmintic resistance, yet very few field studies have allowed these questions to be explored with empirical data. We have analysed individual worm weight data for the parasitic roundworm of humans, Ascaris lumbricoides, collected from a three-round chemo-expulsion study in Dhaka, Bangladesh, with the aim of discerning whether a trickle or a clumped infection process predominates. We found that hosts tend to harbour female worms of a similar weight, indicative of a clumped infection process, but acknowledged that unmeasured host heterogeneities (random effects) could not be completely excluded as a cause. Here, we complement our previous statistical analyses using a stochastic infection model to simulate sizes of individual A. lumbricoides infecting a population of humans. We use the intraclass correlation coefficient (ICC) as a quantitative measure of similarity among simulated worm sizes and explore the behaviour of this statistic under assumptions corresponding to trickle or clumped infections and unmeasured host heterogeneities. We confirm that both mechanisms are capable of generating aggregates of similar-sized worms, but that the particular pattern of ICCs described pre- and post-anthelmintic treatment in the data is more consistent with aggregation generated by clumped infections than by host heterogeneities alone. This provides support to the notion that worms may be acquired in clumps. We discuss our results in terms of the population biology of A. lumbricoides and highlight the significance of our modelling approach for the study of the

  20. Foodborne parasites from wildlife

    DEFF Research Database (Denmark)

    Kapel, Christian Moliin Outzen; Fredensborg, Brian Lund

    2015-01-01

    The majority of wild foods consumed by humans are sourced from intensively managed or semi-farmed populations. Management practices inevitably affect wildlife density and habitat characteristics, which are key elements in the transmission of parasites. We consider the risk of transmission...... of foodborne parasites to humans from wildlife maintained under natural or semi-natural conditions. A deeper understanding will be useful in counteracting foodborne parasites arising from the growing industry of novel and exotic foods....

  1. Lysine Deacetylase Inhibitors in Parasites: Past, Present, and Future Perspectives.

    Science.gov (United States)

    Hailu, Gebremedhin S; Robaa, Dina; Forgione, Mariantonietta; Sippl, Wolfgang; Rotili, Dante; Mai, Antonello

    2017-06-22

    Current therapies for human parasite infections rely on a few drugs, most of which have severe side effects, and their helpfulness is being seriously compromised by the drug resistance problem. Globally, this is pushing discovery research of antiparasitic drugs toward new agents endowed with new mechanisms of action. By using a "drug repurposing" strategy, histone deacetylase inhibitors (HDACi), which are presently clinically approved for cancer use, are now under investigation for various parasite infections. Because parasitic Zn 2+ - and NAD + -dependent HDACs play crucial roles in the modulation of parasite gene expression and many of them are pro-survival for several parasites under various conditions, they are now emerging as novel potential antiparasitic targets. This Perspective summarizes the state of knowledge of HDACi (both class I/II HDACi and sirtuin inhibitors) targeted to the main human parasitic diseases (schistosomiasis, malaria, trypanosomiasis, leishmaniasis, and toxoplasmosis) and provides visions into the main issues that challenge their development as antiparasitic agents.

  2. Human presence increases parasitic load in endangered lion-tailed macaques (Macaca silenus in its fragmented rainforest habitats in Southern India.

    Directory of Open Access Journals (Sweden)

    Shaik Hussain

    Full Text Available BACKGROUND: Understanding changes in the host-parasite relationship due to habitat fragmentation is necessary for better management and conservation of endangered species in fragmented landscapes. Pathogens and parasites can pose severe threat to species in restricted environments such as forest fragments where there is increased contact of wildlife with human and livestock populations. Environmental stress and reduced nutritional level in forest fragments can influence parasite infection and intensity on the native species. In this study, we examine the impact of habitat fragmentation on the prevalence of gastrointestinal parasites in lion-tailed macaques in a fragmented rainforest in Western Ghats. METHODS: The prevalence of different gastrointestinal parasites was estimated from 91 fecal samples collected from 9 lion-tailed macaque groups in nine forest fragments. The parasites were identified up to genus level on the basis of the morphology and coloration of the egg, larva and cyst. The covariates included forest fragment area, group size and the presence/absence of human settlements and livestock in proximity. We used a linear regression model to identify the covariates that significantly influenced the prevalence of different parasite taxa. RESULTS: Nine gastrointestinal parasite taxa were detected in lion-tailed macaque groups. The groups near human settlements had greater prevalence and number of taxa, and these variables also had significant positive correlations with group size. We found that these parameters were also greater in groups near human settlements after controlling for group size. Livestock were present in all five fragments that had human settlements in proximity. CONCLUSION: The present study suggests that high prevalence and species richness of gastrointestinal parasites in lion-tailed macaque groups are directly related to habitat fragmentation, high anthropogenic activities and high host density. The parasite load

  3. Defining the protein interaction network of human malaria parasite Plasmodium falciparum

    KAUST Repository

    Ramaprasad, Abhinay; Pain, Arnab; Ravasi, Timothy

    2012-01-01

    Malaria, caused by the protozoan parasite Plasmodium falciparum, affects around 225. million people yearly and a huge international effort is directed towards combating this grave threat to world health and economic development. Considerable

  4. SURVEY OF HOUSE RAT INTESTINAL PARASITES FROM SURABAYA DISTRICT, EAST JAVA, INDONESIA THAT CAN CAUSE OPPORTUNISTIC INFECTIONS IN HUMANS.

    Science.gov (United States)

    Prasetyo, R H

    2016-03-01

    The purpose of this study was to investigate the prevalence of house rat zoonotic intestinal parasites from Surabaya District, East Java, Indonesia that have the potential to cause opportunistic infection in humans. House rat fecal samples were collected from an area of Surabaya District with a dense rat population during May 2015. Intestinal parasites were detected microscopically using direct smear of feces stained with Lugol's iodine and modified Ziehl-Neelsen stains. The fecal samples were also cultured for Strongyloides stercoralis. Ninety-eight house rat fecal samples were examined. The potential opportunistic infection parasite densities found in those samples were Strongyloides stercoralis in 53%, Hymenolepis nana in 42%, Cryptosporidium spp in 33%, and Blastocystis spp in 6%. This is the first report of this kind in Surabaya District. Measures need to be taken to control the house rat population in the study area to reduce the risk of the public health problem. Keywords: zoonotic intestinal parasites, opportunistic infection, house rat, densely populated area, Indonesia

  5. Human behavior and opportunities for parasite transmission in communities surrounding long-tailed macaque populations in Bali, Indonesia.

    Science.gov (United States)

    Lane-DeGraaf, Kelly E; Putra, I G A Arta; Wandia, I Nengah; Rompis, Aida; Hollocher, Hope; Fuentes, Agustin

    2014-02-01

    Spatial overlap and shared resources between humans and wildlife can exacerbate parasite transmission dynamics. In Bali, Indonesia, an agricultural-religious temple system provides sanctuaries for long-tailed macaques (Macaca fascicularis), concentrating them in areas in close proximity to humans. In this study, we interviewed individuals in communities surrounding 13 macaque populations about their willingness to participate in behaviors that would put them at risk of exposure to gastrointestinal parasites to understand if age, education level, or occupation are significant determinants of exposure behaviors. These exposure risk behaviors and attitudes include fear of macaques, direct contact with macaques, owning pet macaques, hunting and eating macaques, and overlapping water uses. We find that willingness to participate in exposure risk behaviors are correlated with an individual's occupation, age, and/or education level. We also found that because the actual risk of infection varies across populations, activities such as direct macaque contact and pet ownership, could be putting individuals at real risk in certain contexts. Thus, we show that human demographics and social structure can influence willingness to participate in behaviors putting them at increased risk for exposure to parasites. © 2013 Wiley Periodicals, Inc.

  6. Prevalence and Risk Factors of Human Intestinal Parasites in Roudehen, Tehran Province, Iran.

    Science.gov (United States)

    Hemmati, Nasrin; Razmjou, Elham; Hashemi-Hafshejani, Saeideh; Motevalian, Abbas; Akhlaghi, Lameh; Meamar, Ahmad Reza

    2017-01-01

    Intestinal parasitic infections are among the most common infections and health problems worldwide. Due to the lack of epidemiologic information of such infections, the prevalence of, and the risk factors for, enteric parasites were investigated in residents of Roudehen, Tehran Province, Iran. In this cross-sectional study, 561 triple fecal samples were collected through a two-stage cluster-sampling protocol from Jun to Dec 2014. The samples were examined by formalin-ether concentration, culture, and with molecular methods. The prevalence of enteric parasites was 32.7% (95% CI 27.3-38). Blastocystis sp. was the most common intestinal protozoan (28.4%; 95% CI 23.7-33.0). The formalin-ether concentration and culture methods detected Blastocystis sp., Entamoeba coli , Giardia intestinalis , Dientamoeba fragilis , Iodamoeba butschlii , Entamoeba complex cysts or trophozoite , Chilomastix mesnilii , and Enterobius vermicularis . Single-round PCR assay for Entamoeba complex were identified Entamoeba dispar and E. moshkovskii . E. histolytica was not observed in any specimen. Multivariate analysis showed a significant association of parasites with water source and close animal contact. There was no correlation between infections and gender, age, occupation, education, or travel history. Protozoan infections were more common than helminth infections. This study revealed a high prevalence of enteric protozoan parasite infection among citizens of Rodehen. As most of the species detected are transmitted through a water-resistant cyst, public and individual education on personal hygiene should be considered to reduce transmission of intestinal parasites in the population.

  7. Human-induced eutrophication maintains high parasite prevalence in breeding threespine stickleback populations.

    Science.gov (United States)

    Budria, Alexandre; Candolin, Ulrika

    2015-04-01

    Anthropogenic activities are having profound impacts on species interactions, with further consequences for populations and communities. We investigated the influence that anthropogenic eutrophication has on the prevalence of the parasitic tapeworm Schistocephalus solidus in threespine stickleback Gasterosteus aculeatus populations. We caught stickleback from four areas along the coast of Finland, and within each area from one undisturbed and one eutrophied habitat. We found the prevalence of the parasite to be lower in the eutrophied habitats at the start of the breeding season, probably because of fewer piscivorous birds that transmit the parasite. However, while the prevalence of the parasite declined across the season in the undisturbed habitat, it did less so in eutrophied habitats. We discuss different processes that could be behind the differences, such as lower predation rate on infected fish, higher food availability and less dispersal in eutrophied habitats. We found no effect of eutrophication on the proportion of infected stickleback that entered reproductive condition. Together with earlier findings, this suggests that eutrophication increases the proportion of infected stickleback that reproduce. This could promote the evolution of less parasite resistant populations, with potential consequences for the viability of the interacting parties of the host-parasite system.

  8. SAM domain-dependent activity of PfTKL3, an essential tyrosine kinase-like kinase of the human malaria parasite Plasmodium falciparum.

    Science.gov (United States)

    Abdi, Abdirahman; Eschenlauer, Sylvain; Reininger, Luc; Doerig, Christian

    2010-10-01

    Over the last decade, several protein kinases inhibitors have reached the market for cancer chemotherapy. The kinomes of pathogens represent potentially attractive targets in infectious diseases. The functions of the majority of protein kinases of Plasmodium falciparum, the parasitic protist responsible for the most virulent form of human malaria, remain unknown. Here we present a thorough characterisation of PfTKL3 (PF13_0258), an enzyme that belongs to the tyrosine kinase-like kinase (TKL) group. We demonstrate by reverse genetics that PfTKL3 is essential for asexual parasite proliferation in human erythrocytes. PfTKL3 is expressed in both asexual and gametocytes stages, and in the latter the protein co-localises with cytoskeleton microtubules. Recombinant PfTKL3 displays in vitro autophosphorylation activity and is able to phosphorylate exogenous substrates, and both activities are dramatically dependent on the presence of an N-terminal "sterile alpha-motif" domain. This study identifies PfTKL3 as a validated drug target amenable to high-throughput screening.

  9. The Chagas disease domestic transmission cycle in Guatemala: Parasite-vector switches and lack of mitochondrial co-diversification between Triatoma dimidiata and Trypanosoma cruzi subpopulations suggest non-vectorial parasite dispersal across the Motagua valley.

    Science.gov (United States)

    Pennington, Pamela M; Messenger, Louisa Alexandra; Reina, Jeffrey; Juárez, José G; Lawrence, Gena G; Dotson, Ellen M; Llewellyn, Martin S; Cordón-Rosales, Celia

    2015-11-01

    Parasites transmitted by insects must adapt to their vectors and reservoirs. Chagas disease, an American zoonosis caused by Trypanosoma cruzi, is transmitted by several species of triatomines. In Central America, Triatoma dimidiata is a widely dispersed vector found in sylvatic and domestic habitats, with distinct populations across the endemic region of Guatemala. Our aim was to test the strength of association between vector and parasite genetic divergence in domestic environments. Microsatellite (MS) loci were used to characterize parasites isolated from T. dimidiata (n=112) collected in domestic environments. Moderate genetic differentiation was observed between parasites north and south of the Motagua Valley, an ancient biogeographic barrier (FST 0.138, p=0.009). Slightly reduced genotypic diversity and increased heterozygosity in the north (Allelic richness (Ar)=1.00-6.05, FIS -0.03) compared to the south (Ar=1.47-6.30, FIS 0.022) suggest either a selective or demographic process during parasite dispersal. Based on parasite genotypes and geographic distribution, 15 vector specimens and their parasite isolates were selected for mitochondrial co-diversification analysis. Genetic variability and phylogenetic congruence were determined with mitochondrial DNA sequences (10 parasite maxicircle gene fragments and triatomine ND4+CYT b). A Mantel test as well as phylogenetic, network and principal coordinates analyses supported at least three T. dimidiata haplogroups separated by geographic distance across the Motagua Valley. Maxicircle sequences showed low T. cruzi genetic variability (π nucleotide diversity 0.00098) with no evidence of co-diversification with the vector, having multiple host switches across the valley. Sylvatic Didelphis marsupialis captured across the Motagua Valley were found to be infected with T. cruzi strains sharing MS genotypes with parasites isolated from domiciliated triatomines. The current parasite distribution in domestic environments

  10. Laboratory Diagnosis of Parasites from the Gastrointestinal Tract.

    Science.gov (United States)

    Garcia, Lynne S; Arrowood, Michael; Kokoskin, Evelyne; Paltridge, Graeme P; Pillai, Dylan R; Procop, Gary W; Ryan, Norbert; Shimizu, Robyn Y; Visvesvara, Govinda

    2018-01-01

    This Practical Guidance for Clinical Microbiology document on the laboratory diagnosis of parasites from the gastrointestinal tract provides practical information for the recovery and identification of relevant human parasites. The document is based on a comprehensive literature review and expert consensus on relevant diagnostic methods. However, it does not include didactic information on human parasite life cycles, organism morphology, clinical disease, pathogenesis, treatment, or epidemiology and prevention. As greater emphasis is placed on neglected tropical diseases, it becomes highly probable that patients with gastrointestinal parasitic infections will become more widely recognized in areas where parasites are endemic and not endemic. Generally, these methods are nonautomated and require extensive bench experience for accurate performance and interpretation. Copyright © 2017 American Society for Microbiology.

  11. Lysophosphatidylcholine Regulates Sexual Stage Differentiation in the Human Malaria Parasite Plasmodium falciparum.

    Science.gov (United States)

    Brancucci, Nicolas M B; Gerdt, Joseph P; Wang, ChengQi; De Niz, Mariana; Philip, Nisha; Adapa, Swamy R; Zhang, Min; Hitz, Eva; Niederwieser, Igor; Boltryk, Sylwia D; Laffitte, Marie-Claude; Clark, Martha A; Grüring, Christof; Ravel, Deepali; Blancke Soares, Alexandra; Demas, Allison; Bopp, Selina; Rubio-Ruiz, Belén; Conejo-Garcia, Ana; Wirth, Dyann F; Gendaszewska-Darmach, Edyta; Duraisingh, Manoj T; Adams, John H; Voss, Till S; Waters, Andrew P; Jiang, Rays H Y; Clardy, Jon; Marti, Matthias

    2017-12-14

    Transmission represents a population bottleneck in the Plasmodium life cycle and a key intervention target of ongoing efforts to eradicate malaria. Sexual differentiation is essential for this process, as only sexual parasites, called gametocytes, are infective to the mosquito vector. Gametocyte production rates vary depending on environmental conditions, but external stimuli remain obscure. Here, we show that the host-derived lipid lysophosphatidylcholine (LysoPC) controls P. falciparum cell fate by repressing parasite sexual differentiation. We demonstrate that exogenous LysoPC drives biosynthesis of the essential membrane component phosphatidylcholine. LysoPC restriction induces a compensatory response, linking parasite metabolism to the activation of sexual-stage-specific transcription and gametocyte formation. Our results reveal that malaria parasites can sense and process host-derived physiological signals to regulate differentiation. These data close a critical knowledge gap in parasite biology and introduce a major component of the sexual differentiation pathway in Plasmodium that may provide new approaches for blocking malaria transmission. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  12. Methodology and application of flow cytometry for investigation of human malaria parasites.

    Science.gov (United States)

    Grimberg, Brian T

    2011-03-31

    Historically, examinations of the inhibition of malaria parasite growth/invasion, whether using drugs or antibodies, have relied on the use of microscopy or radioactive hypoxanthine uptake. These are considered gold standards for measuring the effectiveness of antimalarial treatments, however, these methods have well known shortcomings. With the advent of flow cytometry coupled with the use of fluorescent DNA stains allowed for increased speed, reproducibility, and qualitative estimates of the effectiveness of antibodies and drugs to limit malaria parasite growth which addresses the challenges of traditional techniques. Because materials and machines available to research facilities are so varied, different methods have been developed to investigate malaria parasites by flow cytometry. This review is intended to serve as a reference guide for advanced users and importantly, as a primer for new users, to support expanded use and improvements to malaria flow cytometry, particularly in endemic countries. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. Prevalence and Risk Factors of Human Intestinal Parasites in Roudehen, Tehran Province, Iran

    Directory of Open Access Journals (Sweden)

    Nasrin HEMMATI

    2017-09-01

    Full Text Available Background: Intestinal parasitic infections are among the most common infections and health problems worldwide. Due to the lack of epidemiologic information of such infections, the prevalence of, and the risk factors for, enteric parasites were investigated in residents of Roudehen, Tehran Province, Iran.Methods: In this cross-sectional study, 561 triple fecal samples were collected through a two-stage cluster-sampling protocol from Jun to Dec 2014. The samples were examined by formalin-ether concentration, culture, and with molecular methods.Results: The prevalence of enteric parasites was 32.7% (95% CI 27.3–38. Blastocystis sp. was the most common intestinal protozoan (28.4%; 95% CI 23.7–33.0. The formalin-ether concentration and culture methods detected Blastocystis sp., Entamoeba coli, Giardia intestinalis, Dientamoeba fragilis, Iodamoeba butschlii, Entamoeba complex cysts or trophozoite, Chilomastix mesnilii, and Enterobius vermicularis. Single-round PCR assay for Entamoeba complex were identified Entamoeba dispar and E. moshkovskii. E. histolytica was not observed in any specimen. Multivariate analysis showed a significant association of parasites with water source and close animal contact. There was no correlation between infections and gender, age, occupation, education, or travel history. Protozoan infections were more common than helminth infections.Conclusion: This study revealed a high prevalence of enteric protozoan parasite infection among citizens of Rodehen. As most of the species detected are transmitted through a water-resistant cyst, public and individual education on personal hygiene should be considered to reduce transmission of intestinal parasites in the population. 

  14. Successes against insects and parasites

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1967-10-15

    With more and more answers being found to intricate problems which have entailed years of research in many parts of the world, some successes can now be claimed in the fight to control insect threats to crops, animals and human beings. Nuclear techniques are playing an important part in world efforts, and recent reports show that they have been effective in pioneer work against crop pests as well as in finding an answer to some diseases caused by parasites

  15. Parasites in marine food webs

    Science.gov (United States)

    Lafferty, Kevin D.

    2013-01-01

    Most species interactions probably involve parasites. This review considers the extent to which marine ecologists should consider parasites to fully understand marine communities. Parasites are influential parts of food webs in estuaries, temperate reefs, and coral reefs, but their ecological importance is seldom recognized. Though difficult to observe, parasites can have substantial biomass, and they can be just as common as free-living consumers after controlling for body mass and trophic level. Parasites have direct impacts on the energetics of their hosts and some affect host behaviors, with ecosystem-level consequences. Although they cause disease, parasites are sensitive components of ecosystems. In particular, they suffer secondary extinctions due to biodiversity loss. Some parasites can also return to a system after habitat restoration. For these reasons, parasites can make good indicators of ecosystem integrity. Fishing can indirectly increase or decrease parasite populations and the effects of climate change on parasites are likely to be equally as complex.

  16. Parasites, Plants, and People.

    Science.gov (United States)

    Johnson, Marion; Moore, Tony

    2016-06-01

    Anthelminthic resistance is acknowledged worldwide and is a major problem in Aotearoa New Zealand, thus alternative parasite management strategies are imperative. One Health is an initiative linking animal, human, and environmental health. Parasites, plants, and people illustrate the possibilities of providing diverse diets for stock thereby lowering parasite burdens, improving the cultural wellbeing of a local community, and protecting the environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Distinct genetic control of parasite elimination, dissemination, and disease after Leishmania major infection

    Czech Academy of Sciences Publication Activity Database

    Kurey, Irina; Kobets, Tetyana; Havelková, Helena; Slapničková, Martina; Quan, L.; Trtková, Kateřina; Grekov, Igor; Svobodová, M.; Stassen, A. P. M.; Hutson, A.; Demant, P.; Lipoldová, Marie

    2009-01-01

    Roč. 61, č. 9 (2009), s. 619-633 ISSN 0093-7711 R&D Projects: GA ČR GA310/06/1745; GA MŠk(CZ) LC06009 Grant - others:EC(XE) 05-1000004-7761 Institutional research plan: CEZ:AV0Z50520514 Keywords : Leishmania major * Parasite elimination * QTL mapping Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.988, year: 2009

  18. Infections and parasitic diseases of the gray wolf and their potential effects on wolf populations in North America.

    Science.gov (United States)

    Brand, C.J.; Pybus, M.J.; Ballard, W.B.; Peterson, R.O.

    1995-01-01

    Numerous infections and parasitic diseases have been reported for the gray wolf, including more than 10 viral, bacterial, and mycotic disease and more than 70 species of helminths and ectoparasites. However, few studies have documented the role of diseases in population dynamics. Disease can affect wolf populations directly by causing mortality or indirectly by affecting physiological and homeostatic processes, thriftiness, reproduction, behavior, or social structure. In addition, wolves are hosts to diseases that can affect prey species, thus affecting wolf populations indirectly by reducing prey abundance or increasing vulnerability to predation. Diseases such as canine distemper and infectious canine hepatitis are enzootic in wolf populations, whereas rabies occurs in wolves primarily as a result of transmission from other species such as artic and red foxes. Contact between wolves and domestic pets and livestock may affect the composition of diseases in wolves and their effects on wolf populations. Dogs were suspected of introducing lice and canine parovirus to several wolf populations. THe potential for disease to affect wolf populations and other wild and domestic animals should be considered in wolf management plans, particularly in plans for reintroduction of wolves to area within their former range.

  19. Protein export marks the early phase of gametocytogenesis of the human malaria parasite Plasmodium falciparum.

    NARCIS (Netherlands)

    Silvestrini, F.; Lasonder, E.; Olivieri, A.; Camarda, G.; Schaijk, B.C.L. van; Sanchez, M.; Younis Younis, S.; Sauerwein, R.W.; Alano, P.

    2010-01-01

    Despite over a century of study of malaria parasites, parts of the Plasmodium falciparum life cycle remain virtually unknown. One of these is the early gametocyte stage, a round shaped cell morphologically similar to an asexual trophozoite in which major cellular transformations ensure subsequent

  20. Expression of senescent antigen on erythrocytes infected with a knobby variant of the human malaria parasite Plasmodium falciparum

    International Nuclear Information System (INIS)

    Winograd, E.; Greenan, J.R.T.; Sherman, I.W.

    1987-01-01

    Erythrocytes infected with a knobby variant of Plasmodium falciparum selectively bind IgG autoantibodies in normal human serum. Quantification of membrane-bound IgG, by use of 125 I-labeled protein A, revealed that erythrocytes infected with the knobby variant bound 30 times more protein A than did noninfected erythrocytes; infection with a knobless variant resulted in less than a 2-fold difference compared with noninfected erythrocytes. IgG binding to knobby erythrocytes appeared to be related to parasite development, since binding of 125 I-labeled protein A to cells bearing young trophozoites (less than 20 hr after parasite invasion) was similar to binding to uninfected erythrocytes. By immunoelectron microscopy, the membrane-bound IgG on erythrocytes infected with the knobby variant was found to be preferentially associated with the protuberances (knobs) of the plasma membrane. The removal of aged or senescent erythrocytes from the peripheral circulation is reported to involve the binding of specific antibodies to an antigen (senescent antigen) related to the major erythrocyte membrane protein band 3. Since affinity-purified autoantibodies against band 3 specifically bound to the plasma membrane of erythrocytes infected with the knobby variant of P. falciparum, it is clear that the malaria parasite induces expression of senescent antigen

  1. Mast Cell Coupling to the Kallikrein–Kinin System Fuels Intracardiac Parasitism and Worsens Heart Pathology in Experimental Chagas Disease

    Directory of Open Access Journals (Sweden)

    Clarissa R. Nascimento

    2017-08-01

    Full Text Available During the course of Chagas disease, infectious forms of Trypanosoma cruzi are occasionally liberated from parasitized heart cells. Studies performed with tissue culture trypomastigotes (TCTs, Dm28c strain demonstrated that these parasites evoke neutrophil/CXCR2-dependent microvascular leakage by activating innate sentinel cells via toll-like receptor 2 (TLR2. Upon plasma extravasation, proteolytically derived kinins and C5a stimulate immunoprotective Th1 responses via cross-talk between bradykinin B2 receptors (B2Rs and C5aR. Awareness that TCTs invade cardiovascular cells in vitro via interdependent activation of B2R and endothelin receptors [endothelin A receptor (ETAR/endothelin B receptor (ETBR] led us to hypothesize that T. cruzi might reciprocally benefit from the formation of infection-associated edema via activation of kallikrein–kinin system (KKS. Using intravital microscopy, here we first examined the functional interplay between mast cells (MCs and the KKS by topically exposing the hamster cheek pouch (HCP tissues to dextran sulfate (DXS, a potent “contact” activator of the KKS. Surprisingly, although DXS was inert for at least 30 min, a subtle MC-driven leakage resulted in factor XII (FXII-dependent activation of the KKS, which then amplified inflammation via generation of bradykinin (BK. Guided by this mechanistic insight, we next exposed TCTs to “leaky” HCP—forged by low dose histamine application—and found that the proinflammatory phenotype of TCTs was boosted by BK generated via the MC/KKS pathway. Measurements of footpad edema in MC-deficient mice linked TCT-evoked inflammation to MC degranulation (upstream and FXII-mediated generation of BK (downstream. We then inoculated TCTs intracardiacally in mice and found a striking decrease of parasite DNA (quantitative polymerase chain reaction; 3 d.p.i. in the heart of MC-deficient mutant mice. Moreover, the intracardiac parasite load was significantly reduced in WT

  2. Animal models for human genetic diseases

    African Journals Online (AJOL)

    Sharif Sons

    The study of human genetic diseases can be greatly aided by animal models because of their similarity .... and gene targeting in embryonic stem cells) has been a powerful tool in .... endonucleases that are designed to make a doublestrand.

  3. Roentgenosemiotics and diagnosis of human diseases

    International Nuclear Information System (INIS)

    Mikhajlov, A.N.

    1989-01-01

    Modern concepts concerning roentgenologic semiotics, diagnosis of almost all the human diseases as well as the features of roentgenologic examintion of organs and systems are described. Roentgenologic symptoms and syndroms are systematized and standardized by anatomy branches. 48 refs

  4. Reorganization of Extracellular Matrix in Placentas from Women with Asymptomatic Chagas Disease: Mechanism of Parasite Invasion or Local Placental Defense?

    Directory of Open Access Journals (Sweden)

    Juan Duaso

    2012-01-01

    Full Text Available Chagas disease, produced by the protozoan Trypanosoma cruzi (T. cruzi, is one of the most frequent endemic diseases in Latin America. In spite the fact that in the past few years T. cruzi congenital transmission has become of epidemiological importance, studies about this mechanism of infection are scarce. In order to explore some morphological aspects of this infection in the placenta, we analyzed placentas from T. cruzi-infected mothers by immunohistochemical and histochemical methods. Infection in mothers, newborns, and placentas was confirmed by PCR and by immunofluorescence in the placenta. T. cruzi-infected placentas present destruction of the syncytiotrophoblast and villous stroma, selective disorganization of the basal lamina, and disorganization of collagen I in villous stroma. Our results suggest that the parasite induces reorganization of this tissue component and in this way may regulate both inflammatory and immune responses in the host. Changes in the ECM of placental tissues, together with the immunological status of mother and fetus, and parasite load may determine the probability of congenital transmission of T. cruzi.

  5. Protein Misfolding and Human Disease

    DEFF Research Database (Denmark)

    Gregersen, Niels; Bross, Peter Gerd; Vang, Søren

    2006-01-01

    phenylketonuria, Parkinson's disease, α-1-antitrypsin deficiency, familial neurohypophyseal diabetes insipidus, and short-chain acyl-CoA dehydrogenase deficiency. Despite the differences, an emerging paradigm suggests that the cellular effects of protein misfolding provide a common framework that may contribute...

  6. Annotating the human genome with Disease Ontology

    Science.gov (United States)

    Osborne, John D; Flatow, Jared; Holko, Michelle; Lin, Simon M; Kibbe, Warren A; Zhu, Lihua (Julie); Danila, Maria I; Feng, Gang; Chisholm, Rex L

    2009-01-01

    Background The human genome has been extensively annotated with Gene Ontology for biological functions, but minimally computationally annotated for diseases. Results We used the Unified Medical Language System (UMLS) MetaMap Transfer tool (MMTx) to discover gene-disease relationships from the GeneRIF database. We utilized a comprehensive subset of UMLS, which is disease-focused and structured as a directed acyclic graph (the Disease Ontology), to filter and interpret results from MMTx. The results were validated against the Homayouni gene collection using recall and precision measurements. We compared our results with the widely used Online Mendelian Inheritance in Man (OMIM) annotations. Conclusion The validation data set suggests a 91% recall rate and 97% precision rate of disease annotation using GeneRIF, in contrast with a 22% recall and 98% precision using OMIM. Our thesaurus-based approach allows for comparisons to be made between disease containing databases and allows for increased accuracy in disease identification through synonym matching. The much higher recall rate of our approach demonstrates that annotating human genome with Disease Ontology and GeneRIF for diseases dramatically increases the coverage of the disease annotation of human genome. PMID:19594883

  7. DNA typing of ancient parasite eggs from environmental samples identifies human and animal worm infections in viking-age settlement

    DEFF Research Database (Denmark)

    Søe, Martin Jensen; Nejsum, Peter; Fredensborg, Brian Lund

    2015-01-01

    Ancient parasite eggs were recovered from environmental samples collected at a Viking-age settlement in Viborg, Denmark, dated 1018-1030 A.D. Morphological examination identified Ascaris sp., Trichuris sp., and Fasciola sp. eggs, but size and shape did not allow species identification. By carefully...... selecting genetic markers, PCR amplification and sequencing of ancient DNA (aDNA) isolates resulted in identification of: the human whipworm, Trichuris trichiura, using SSUrRNA sequence homology; Ascaris sp. with 100% homology to cox1 haplotype 07; and Fasciola hepatica using ITS1 sequence homology...

  8. A global comparison of the human and T. brucei degradomes gives insights about possible parasite drug targets.

    Directory of Open Access Journals (Sweden)

    Susan T Mashiyama

    Full Text Available We performed a genome-level computational study of sequence and structure similarity, the latter using crystal structures and models, of the proteases of Homo sapiens and the human parasite Trypanosoma brucei. Using sequence and structure similarity networks to summarize the results, we constructed global views that show visually the relative abundance and variety of proteases in the degradome landscapes of these two species, and provide insights into evolutionary relationships between proteases. The results also indicate how broadly these sequence sets are covered by three-dimensional structures. These views facilitate cross-species comparisons and offer clues for drug design from knowledge about the sequences and structures of potential drug targets and their homologs. Two protease groups ("M32" and "C51" that are very different in sequence from human proteases are examined in structural detail, illustrating the application of this global approach in mining new pathogen genomes for potential drug targets. Based on our analyses, a human ACE2 inhibitor was selected for experimental testing on one of these parasite proteases, TbM32, and was shown to inhibit it. These sequence and structure data, along with interactive versions of the protein similarity networks generated in this study, are available at http://babbittlab.ucsf.edu/resources.html.

  9. A global comparison of the human and T. brucei degradomes gives insights about possible parasite drug targets.

    Science.gov (United States)

    Mashiyama, Susan T; Koupparis, Kyriacos; Caffrey, Conor R; McKerrow, James H; Babbitt, Patricia C

    2012-01-01

    We performed a genome-level computational study of sequence and structure similarity, the latter using crystal structures and models, of the proteases of Homo sapiens and the human parasite Trypanosoma brucei. Using sequence and structure similarity networks to summarize the results, we constructed global views that show visually the relative abundance and variety of proteases in the degradome landscapes of these two species, and provide insights into evolutionary relationships between proteases. The results also indicate how broadly these sequence sets are covered by three-dimensional structures. These views facilitate cross-species comparisons and offer clues for drug design from knowledge about the sequences and structures of potential drug targets and their homologs. Two protease groups ("M32" and "C51") that are very different in sequence from human proteases are examined in structural detail, illustrating the application of this global approach in mining new pathogen genomes for potential drug targets. Based on our analyses, a human ACE2 inhibitor was selected for experimental testing on one of these parasite proteases, TbM32, and was shown to inhibit it. These sequence and structure data, along with interactive versions of the protein similarity networks generated in this study, are available at http://babbittlab.ucsf.edu/resources.html.

  10. Physiochemical basis of human degenerative disease.

    Science.gov (United States)

    Zeliger, Harold I; Lipinski, Boguslaw

    2015-03-01

    The onset of human degenerative diseases in humans, including type 2 diabetes, cardiovascular disease, neurological disorders, neurodevelopmental disease and neurodegenerative disease has been shown to be related to exposures to persistent organic pollutants, including polychlorinated biphenyls, chlorinated pesticides, polybrominated diphenyl ethers and others, as well as to polynuclear aromatic hydrocarbons, phthalates, bisphenol-A and other aromatic lipophilic species. The onset of these diseases has also been related to exposures to transition metal ions. A physiochemical mechanism for the onset of degenerative environmental disease dependent upon exposure to a combination of lipophilic aromatic hydrocarbons and transition metal ions is proposed here. The findings reported here also, for the first time, explain why aromatic hydrocarbons exhibit greater toxicity than aliphatic hydrocarbons of equal carbon numbers.

  11. Physiochemical basis of human degenerative disease

    Directory of Open Access Journals (Sweden)

    Zeliger Harold I.

    2015-03-01

    Full Text Available The onset of human degenerative diseases in humans, including type 2 diabetes, cardiovascular disease, neurological disorders, neurodevelopmental disease and neurodegenerative disease has been shown to be related to exposures to persistent organic pollutants, including polychlorinated biphenyls, chlorinated pesticides, polybrominated diphenyl ethers and others, as well as to polynuclear aromatic hydrocarbons, phthalates, bisphenol-A and other aromatic lipophilic species. The onset of these diseases has also been related to exposures to transition metal ions. A physiochemical mechanism for the onset of degenerative environmental disease dependent upon exposure to a combination of lipophilic aromatic hydrocarbons and transition metal ions is proposed here. The findings reported here also, for the first time, explain why aromatic hydrocarbons exhibit greater toxicity than aliphatic hydrocarbons of equal carbon numbers.

  12. Human diseases associated with defective DNA repair

    International Nuclear Information System (INIS)

    Friedberg, E.C.; Ehmann, U.K.; Williams, J.I.

    1979-01-01

    The observations on xeroderma pigmentosum (XP) cells in culture were the first indications of defective DNA repair in association with human disease. Since then, a wealth of information on DNA repair in XP, and to a lesser extent in other diseases, has accumulated in the literature. Rather than clarifying the understanding of DNA repair mechanisms in normal cells and of defective DNA repair in human disease, the literature suggests an extraordinary complexity of both of the phenomena. In this review a number of discrete human diseases are considered separately. An attempt was made to systematically describe the pertinent clinical features and cellular and biochemical defects in these diseases, with an emphasis on defects in DNA metabolism, particularly DNA repair. Wherever possible observations have been correlated and unifying hypotheses presented concerning the nature of the basic defect(s) in these diseases. Discussions of the following diseases are presented: XP, ataxia telangiectasia; Fanconi's anemia; Hutchinson-Gilford progeria syndrome; Bloom's syndrome, Cockayne's syndrome; Down's syndrome; retinoblastoma; chronic lymphocytic leukemia; and other miscellaneous human diseases with possble DNA repair defects

  13. Molecular Pathology of Human Prion Diseases

    Directory of Open Access Journals (Sweden)

    2009-03-01

    Full Text Available Prion diseases are fatal neurodegenerative conditions in humans and animals. In this review, we summarize the molecular background of phenotypic variability, relation of prion protein (PrP to other proteins associated with neurodegenerative diseases, and pathogenesis of neuronal vulnerability. PrP exists in different forms that may be present in both diseased and non-diseased brain, however, abundant disease-associated PrP together with tissue pathology characterizes prion diseases and associates with transmissibility. Prion diseases have different etiological background with distinct pathogenesis and phenotype. Mutations of the prion protein gene are associated with genetic forms. The codon 129 polymorphism in combination with the Western blot pattern of PrP after proteinase K digestion serves as a basis for molecular subtyping of sporadic Creutzfeldt-Jakob disease. Tissue damage may result from several parallel, interacting or subsequent pathways that involve cellular systems associated with synapses, protein processing, oxidative stress, autophagy, and apoptosis.

  14. Crystallization and preliminary crystallographic studies of a cysteine protease inhibitor from the human nematode parasite Ascaris lumbricoides

    International Nuclear Information System (INIS)

    Liu, Sanling; Dong, Jianmei; Mei, Guoqiang; Liu, Guiyun; Xu, Wei; Su, Zhong; Liu, Jinsong

    2011-01-01

    A recombinant cysteine protease inhibitor from the human nematode parasite A. lumbricoides has been overexpressed in E. coli, purified and crystallized. Diffraction data were collected to 2.1 Å resolution. The cysteine protease inhibitor from Ascaris lumbricoides, a roundworm that lives in the human intestine, may be involved in the suppression of human immune responses. Here, the molecular cloning, protein expression and purification, preliminary crystallization and crystallographic characterization of the cysteine protease inhibitor from A. lumbricoides are reported. The rod-shaped crystal belonged to space group C2, with unit-cell parameters a = 99.40, b = 37.52, c = 62.92 Å, β = 118.26°. The crystal diffracted to 2.1 Å resolution and contained two molecules in the asymmetric unit

  15. Melatonin and human mitochondrial diseases

    Directory of Open Access Journals (Sweden)

    Reza Sharafati-Chaleshtori

    2017-01-01

    Full Text Available Mitochondrial dysfunction is one of the main causative factors in a wide variety of complications such as neurodegenerative disorders, ischemia/reperfusion, aging process, and septic shock. Decrease in respiratory complex activity, increase in free radical production, increase in mitochondrial synthase activity, increase in nitric oxide production, and impair in electron transport system and/or mitochondrial permeability are considered as the main factors responsible for mitochondrial dysfunction. Melatonin, the pineal gland hormone, is selectively taken up by mitochondria and acts as a powerful antioxidant, regulating the mitochondrial bioenergetic function. Melatonin increases the permeability of membranes and is the stimulator of antioxidant enzymes including superoxide dismutase, glutathione peroxidase, glutathione reductase, and catalase. It also acts as an inhibitor of lipoxygenase. Melatonin can cause resistance to oxidation damage by fixing the microsomal membranes. Melatonin has been shown to retard aging and inhibit neurodegenerative disorders, ischemia/reperfusion, septic shock, diabetes, cancer, and other complications related to oxidative stress. The purpose of the current study, other than introducing melatonin, was to present the recent findings on clinical effects in diseases related to mitochondrial dysfunction including diabetes, cancer, gastrointestinal diseases, and diseases related to brain function.

  16. Plebotomine Vectors of Human Disease.

    Science.gov (United States)

    1984-12-30

    incriminated as vectors of Leishmania mexicana among rodents and/or humans from Mexico to the Amazon Basin. Specimens referable to L. olmeca olmeca...in the format similar to that given for the species group baityi included in this report. Additional phlebotomines from Tanzania, Brazil, Peru and...species group baityi included in this report. Additional phlebotomines from Tanzania, Brazil, Peru and Venezuela were slide-mounted and added to the

  17. Genomic uracil and human disease

    DEFF Research Database (Denmark)

    Hagen, Lars; Pena Diaz, Javier; Kavli, Bodil

    2006-01-01

    Uracil is present in small amounts in DNA due to spontaneous deamination of cytosine and incorporation of dUMP during replication. While deamination generates mutagenic U:G mismatches, incorporated dUMP results in U:A pairs that are not directly mutagenic, but may be cytotoxic. In most cells, mut...... retroviral infections. Ung(-/-) mice have a similar phenotype and develop B-cell lymphomas late in life. However, there is no evidence indicating that UNG deficiency causes lymphomas in humans....

  18. Helminth allergens, parasite-specific IgE and its protective role in human immunity

    Directory of Open Access Journals (Sweden)

    Colin Matthew Fitzsimmons

    2014-02-01

    Full Text Available The Th2 immune response, culminating in eosinophilia and IgE production, is not only characteristic of allergy but also of infection by parasitic worms (helminths. Anti-parasite IgE has been associated with immunity against a range of helminth infections and many believe that IgE and its receptors evolved to help counter metazoan parasites. Allergens (IgE-antigens are present in only a small minority of protein families and known IgE targets in helminths belong to these same families (e.g. EF-hand proteins, tropomyosin, and PR-1 proteins.During some helminth infection, especially with the well adapted hookworm, the Th2 response is moderated by parasite-expressed molecules. This has been associated with reduced allergy in helminth endemic areas and worm infection or products have been proposed as treatments for allergic conditions. However some infections (especially Ascaris are associated with increased allergy and this has been linked to cross-reactivity between worm proteins (e.g., tropomyosins and highly similar molecules in dust mites and insects. The overlap between allergy and helminth infection is best illustrated in Anisakis simplex, a nematode that when consumed in under-cooked fish can be both an infective helminth and a food allergen. Nearly 20 molecular allergens have been isolated from this species, including tropomyosin (Ani s3 and the EF-hand protein, Ani s troponin.In this review, we highlight aspects of the biology and biochemistry of helminths that may have influenced the evolution of the IgE response. We compare dominant IgE antigens in worms with clinically important environmental allergens and suggest that arrays of such molecules will provide important information on anti-worm immunity as well as allergy.

  19. Does Magnetic Field Affect Malaria Parasite Replication in Human Red Blood Cells?

    Science.gov (United States)

    Chanturiya, Alexandr N.; Glushakova, Svetlana; Yin, Dan; Zimmerberg, Joshua

    2004-01-01

    Digestion of red blood cell (RBC) hemoglobin by the malaria parasite results in the formation of paramagnetic hemazoin crystals inside the parasite body. A number of reports suggest that magnetic field interaction with hamazoin crystals significantly reduces the number of infected cells in culture, and thus magnetic field can be used to combat malaria. We studies the effects of magnetic filed on the Plasmodium falciparum asexual life cycle inside RBCs under various experimental conditions. No effect was found during prolonged exposure of infected RBCs to constant magnetic fields up to 6000 Gauss. Infected RBCs were also exposed, under temperature-controlled conditions, to oscillating magnetic fields with frequencies in the range of 500-20000 kHz, and field strength 30-600 Gauss. This exposure often changed the proportion of different parasite stages in treated culture compared to controls. However, no significant effect on parasitemia was observed in treated cultures. This result indicates that the magnetic field effect on Plasmodium falciparum is negligible, or that hypothetical negative and positive effects on different stages within one 48-hour compensate each other.

  20. Human parasites in the Roman World: health consequences of conquering an empire.

    Science.gov (United States)

    Mitchell, Piers D

    2017-01-01

    The archaeological evidence for parasites in the Roman era is presented in order to demonstrate the species present at that time, and highlight the health consequences for people living under Roman rule. Despite their large multi-seat public latrines with washing facilities, sewer systems, sanitation legislation, fountains and piped drinking water from aqueducts, we see the widespread presence of whipworm (Trichuris trichiura), roundworm (Ascaris lumbricoides) and Entamoeba histolytica that causes dysentery. This would suggest that the public sanitation measures were insufficient to protect the population from parasites spread by fecal contamination. Ectoparasites such as fleas, head lice, body lice, pubic lice and bed bugs were also present, and delousing combs have been found. The evidence fails to demonstrate that the Roman culture of regular bathing in the public baths reduced the prevalence of these parasites. Fish tapeworm was noted to be widely present, and was more common than in Bronze and Iron Age Europe. It is possible that the Roman enthusiasm for fermented, uncooked fish sauce (garum) may have facilitated the spread of this helminth. Roman medical practitioners such as Galen were aware of intestinal worms, explaining their existence and planning treatment using the humoural theory of the period.

  1. Sexually Transmitted Diseases (STDs)

    Science.gov (United States)

    ... caused by bacteria, viruses, or parasites. Examples include gonorrhea, genital herpes, human papillomavirus infection, HIV/AIDS, chlamydia, ... genomic sequencing of pathogens responsible for trichomoniasis, chlamydia, gonorrhea, and human genital ulcer disease (chancroid). The sequencing ...

  2. Supplementation with Abscisic Acid Reduces Malaria Disease Severity and Parasite Transmission

    Science.gov (United States)

    Glennon, Elizabeth K. K.; Adams, L. Garry; Hicks, Derrick R.; Dehesh, Katayoon; Luckhart, Shirley

    2016-01-01

    Nearly half of the world's population is at risk for malaria. Increasing drug resistance has intensified the need for novel therapeutics, including treatments with intrinsic transmission-blocking properties. In this study, we demonstrate that the isoprenoid abscisic acid (ABA) modulates signaling in the mammalian host to reduce parasitemia and the formation of transmissible gametocytes and in the mosquito host to reduce parasite infection. Oral ABA supplementation in a mouse model of malaria was well tolerated and led to reduced pathology and enhanced gene expression in the liver and spleen consistent with infection recovery. Oral ABA supplementation also increased mouse plasma ABA to levels that can signal in the mosquito midgut upon blood ingestion. Accordingly, we showed that supplementation of a Plasmodium falciparum-infected blood meal with ABA increased expression of mosquito nitric oxide synthase and reduced infection prevalence in a nitric oxide-dependent manner. Identification of the mechanisms whereby ABA reduces parasite growth in mammals and mosquitoes could shed light on the balance of immunity and metabolism across eukaryotes and provide a strong foundation for clinical translation. PMID:27001761

  3. Genome-wide diversity and differentiation in New World populations of the human malaria parasite Plasmodium vivax.

    Directory of Open Access Journals (Sweden)

    Thais C de Oliveira

    2017-07-01

    Full Text Available The Americas were the last continent colonized by humans carrying malaria parasites. Plasmodium falciparum from the New World shows very little genetic diversity and greater linkage disequilibrium, compared with its African counterparts, and is clearly subdivided into local, highly divergent populations. However, limited available data have revealed extensive genetic diversity in American populations of another major human malaria parasite, P. vivax.We used an improved sample preparation strategy and next-generation sequencing to characterize 9 high-quality P. vivax genome sequences from northwestern Brazil. These new data were compared with publicly available sequences from recently sampled clinical P. vivax isolates from Brazil (BRA, total n = 11 sequences, Peru (PER, n = 23, Colombia (COL, n = 31, and Mexico (MEX, n = 19.We found that New World populations of P. vivax are as diverse (nucleotide diversity π between 5.2 × 10-4 and 6.2 × 10-4 as P. vivax populations from Southeast Asia, where malaria transmission is substantially more intense. They display several non-synonymous nucleotide substitutions (some of them previously undescribed in genes known or suspected to be involved in antimalarial drug resistance, such as dhfr, dhps, mdr1, mrp1, and mrp-2, but not in the chloroquine resistance transporter ortholog (crt-o gene. Moreover, P. vivax in the Americas is much less geographically substructured than local P. falciparum populations, with relatively little between-population genome-wide differentiation (pairwise FST values ranging between 0.025 and 0.092. Finally, P. vivax populations show a rapid decline in linkage disequilibrium with increasing distance between pairs of polymorphic sites, consistent with very frequent outcrossing. We hypothesize that the high diversity of present-day P. vivax lineages in the Americas originated from successive migratory waves and subsequent admixture between parasite lineages from geographically

  4. Genome-wide diversity and differentiation in New World populations of the human malaria parasite Plasmodium vivax.

    Science.gov (United States)

    de Oliveira, Thais C; Rodrigues, Priscila T; Menezes, Maria José; Gonçalves-Lopes, Raquel M; Bastos, Melissa S; Lima, Nathália F; Barbosa, Susana; Gerber, Alexandra L; Loss de Morais, Guilherme; Berná, Luisa; Phelan, Jody; Robello, Carlos; de Vasconcelos, Ana Tereza R; Alves, João Marcelo P; Ferreira, Marcelo U

    2017-07-01

    The Americas were the last continent colonized by humans carrying malaria parasites. Plasmodium falciparum from the New World shows very little genetic diversity and greater linkage disequilibrium, compared with its African counterparts, and is clearly subdivided into local, highly divergent populations. However, limited available data have revealed extensive genetic diversity in American populations of another major human malaria parasite, P. vivax. We used an improved sample preparation strategy and next-generation sequencing to characterize 9 high-quality P. vivax genome sequences from northwestern Brazil. These new data were compared with publicly available sequences from recently sampled clinical P. vivax isolates from Brazil (BRA, total n = 11 sequences), Peru (PER, n = 23), Colombia (COL, n = 31), and Mexico (MEX, n = 19). We found that New World populations of P. vivax are as diverse (nucleotide diversity π between 5.2 × 10-4 and 6.2 × 10-4) as P. vivax populations from Southeast Asia, where malaria transmission is substantially more intense. They display several non-synonymous nucleotide substitutions (some of them previously undescribed) in genes known or suspected to be involved in antimalarial drug resistance, such as dhfr, dhps, mdr1, mrp1, and mrp-2, but not in the chloroquine resistance transporter ortholog (crt-o) gene. Moreover, P. vivax in the Americas is much less geographically substructured than local P. falciparum populations, with relatively little between-population genome-wide differentiation (pairwise FST values ranging between 0.025 and 0.092). Finally, P. vivax populations show a rapid decline in linkage disequilibrium with increasing distance between pairs of polymorphic sites, consistent with very frequent outcrossing. We hypothesize that the high diversity of present-day P. vivax lineages in the Americas originated from successive migratory waves and subsequent admixture between parasite lineages from geographically diverse sites

  5. Genome-wide diversity and differentiation in New World populations of the human malaria parasite Plasmodium vivax

    Science.gov (United States)

    de Oliveira, Thais C.; Rodrigues, Priscila T.; Menezes, Maria José; Gonçalves-Lopes, Raquel M.; Bastos, Melissa S.; Lima, Nathália F.; Barbosa, Susana; Gerber, Alexandra L.; Loss de Morais, Guilherme; Berná, Luisa; Phelan, Jody; Robello, Carlos; de Vasconcelos, Ana Tereza R.

    2017-01-01

    Background The Americas were the last continent colonized by humans carrying malaria parasites. Plasmodium falciparum from the New World shows very little genetic diversity and greater linkage disequilibrium, compared with its African counterparts, and is clearly subdivided into local, highly divergent populations. However, limited available data have revealed extensive genetic diversity in American populations of another major human malaria parasite, P. vivax. Methods We used an improved sample preparation strategy and next-generation sequencing to characterize 9 high-quality P. vivax genome sequences from northwestern Brazil. These new data were compared with publicly available sequences from recently sampled clinical P. vivax isolates from Brazil (BRA, total n = 11 sequences), Peru (PER, n = 23), Colombia (COL, n = 31), and Mexico (MEX, n = 19). Principal findings/Conclusions We found that New World populations of P. vivax are as diverse (nucleotide diversity π between 5.2 × 10−4 and 6.2 × 10−4) as P. vivax populations from Southeast Asia, where malaria transmission is substantially more intense. They display several non-synonymous nucleotide substitutions (some of them previously undescribed) in genes known or suspected to be involved in antimalarial drug resistance, such as dhfr, dhps, mdr1, mrp1, and mrp-2, but not in the chloroquine resistance transporter ortholog (crt-o) gene. Moreover, P. vivax in the Americas is much less geographically substructured than local P. falciparum populations, with relatively little between-population genome-wide differentiation (pairwise FST values ranging between 0.025 and 0.092). Finally, P. vivax populations show a rapid decline in linkage disequilibrium with increasing distance between pairs of polymorphic sites, consistent with very frequent outcrossing. We hypothesize that the high diversity of present-day P. vivax lineages in the Americas originated from successive migratory waves and subsequent admixture between

  6. Survey on the Ability of Wolbachia to Control Human Viral, Protozoan, and Filarial Disease Pathogens

    Directory of Open Access Journals (Sweden)

    Garedaghi Yagoob

    2014-04-01

    Full Text Available Objective: Most human filarial nematode parasites and arthropods are hosts for a bacterial endosymbiont, Wolbachia. In filariasis, Wolbachia are required for normal development, fertility, and survival. However, in arthropods, Wolbachia are largely parasitic and can influence development and reproduction, but are generally not required for host survival. Materials and Methods: Due to their obligate nature in filarial parasites, Wolbachia have been a target for drug discovery initiatives using several approaches including diversity and focused library screening and genomic sequence analysis. Results: In vitro and in vivo anti-Wolbachia antibiotic treatments have been shown to have adulticidal activity, a long sought goal of filarial parasite drug discovery. In mosquitoes, it has been shown that the presence of Wolbachia can inhibit the transmission of certain viruses, such as dengue, chikungunya, yellow fever, West Nile, as well as the infectivity of the malaria-causing protozoan, Plasmodium and filarial nematodes. Conclusion: Wolbachia can cause a form of conditional sterility that can be used to suppress populations of mosquitoes and additional medically important insects. Thus, Wolbachia, a pandemic endosymbiont, offers great potential for elimination of a wide-variety of devastating human diseases.

  7. Genetic diversity of Schistosoma haematobium parasite IS NOT associated with severity of disease in an endemic area in Sudan.

    Science.gov (United States)

    Gasmelseed, Nagla; Karamino, Nhashal E; Abdelwahed, Mohammed O; Hamdoun, Anas O; Elmadani, Ahmed E

    2014-08-27

    Over 650 million people globally are at risk of schistosomiasis infection, while more than 200 million people are infected of which the higher disease rates occur in children. Eighty three students between 6-20 years (mean 12.45 ± 3.2) from Quran School for boys in Radwan village, Gezira state were recruited to investigate for the relationship between the genetic diversity of Schistosoma haematobium strains and the severity of the disease. Schistosoma haematobium infection was detected by filtration of urine. Ultrasonography was done on each study subject, while PCR technique was used for genotyping via random amplified polymorphic DNA (RAPD) with A01, A02, A12, Y20 and A13 primers. A01 primer gave three different genotypes (A01-1, A01-2 and A01-3). About 54.2% (45/83) were S. haematobium egg positive by urine filtration. On assessment of the upper and lower urinary tract by ultrasound technique, 61.4% (51/83) were positiveand73.3% (60/83) samples were PCR positive. No significant difference was found when comparing the three different genotypes with severity of the disease. This study concludes that no association was found between the different genotypes of S.haemtobium and the severity of the disease. Examination of more samples from different areas to identify any possible differences between the parasites genes and disease severity was recommended.

  8. A novel progesterone receptor membrane component (PGRMC) in the human and swine parasite Taenia solium: implications to the host-parasite relationship.

    Science.gov (United States)

    Aguilar-Díaz, Hugo; Nava-Castro, Karen E; Escobedo, Galileo; Domínguez-Ramírez, Lenin; García-Varela, Martín; Del Río-Araiza, Víctor H; Palacios-Arreola, Margarita I; Morales-Montor, Jorge

    2018-03-09

    We have previously reported that progesterone (P 4 ) has a direct in vitro effect on the scolex evagination and growth of Taenia solium cysticerci. Here, we explored the hypothesis that the P 4 direct effect on T. solium might be mediated by a novel steroid-binding parasite protein. By way of using immunofluorescent confocal microscopy, flow cytometry analysis, double-dimension electrophoresis analysis, and sequencing the corresponding protein spot, we detected a novel PGRMC in T. solium. Molecular modeling studies accompanied by computer docking using the sequenced protein, together with phylogenetic analysis and sequence alignment clearly demonstrated that T. solium PGRMC is from parasite origin. Our results show that P 4 in vitro increases parasite evagination and scolex size. Using immunofluorescent confocal microscopy, we detected that parasite cells showed expression of a P 4 -binding like protein exclusively located at the cysticercus subtegumental tissue. Presence of the P 4 -binding protein in cyst cells was also confirmed by flow cytometry. Double-dimension electrophoresis analysis, followed by sequencing the corresponding protein spot, revealed a protein that was previously reported in the T. solium genome belonging to a membrane-associated progesterone receptor component (PGRMC). Molecular modeling studies accompanied by computer docking using the sequenced protein showed that PGRMC is potentially able to bind steroid hormones such as progesterone, estradiol, testosterone and dihydrodrotestosterone with different affinities. Phylogenetic analysis and sequence alignment clearly demonstrated that T. solium PGRMC is related to a steroid-binding protein of Echinoccocus granulosus, both of them being nested within a cluster including similar proteins present in platyhelminths such as Schistocephalus solidus and Schistosoma haematobium. Progesterone may directly act upon T. solium cysticerci probably by binding to PGRMC. This research has implications in the

  9. Nuclear techniques in the study and control of parasitic diseases of livestock

    International Nuclear Information System (INIS)

    1988-01-01

    This publication presents the results of a five-year Co-ordinated Research Programme conducted under the auspices of the Joint FAO/IAEA Division of Isotope and Radiation Applications of Atomic Energy for Food and Agricultural Development. The aims of this programme were to encourage studies on the development of new vaccines or on a more extensive application of the available vaccines, and to stimulate examination of the immunology, pathogenesis and genetics of host-parasite relationships of veterinary importance in developing countries. The individual papers are essentially a synthesis of the work presented by the participants of the programme at a final Research Co-ordination Meeting held in Vienna from 11 to 14 May 1987 as well as work presented at previous meetings in Nairobi and Rabat. Refs, figs and tabs

  10. Asexual populations of the human malaria parasite, Plasmodium falciparum, use a two-step genomic strategy to acquire accurate, beneficial DNA amplifications.

    Directory of Open Access Journals (Sweden)

    Jennifer L Guler

    Full Text Available Malaria drug resistance contributes to up to a million annual deaths. Judicious deployment of new antimalarials and vaccines could benefit from an understanding of early molecular events that promote the evolution of parasites. Continuous in vitro challenge of Plasmodium falciparum parasites with a novel dihydroorotate dehydrogenase (DHODH inhibitor reproducibly selected for resistant parasites. Genome-wide analysis of independently-derived resistant clones revealed a two-step strategy to evolutionary success. Some haploid blood-stage parasites first survive antimalarial pressure through fortuitous DNA duplications that always included the DHODH gene. Independently-selected parasites had different sized amplification units but they were always flanked by distant A/T tracks. Higher level amplification and resistance was attained using a second, more efficient and more accurate, mechanism for head-to-tail expansion of the founder unit. This second homology-based process could faithfully tune DNA copy numbers in either direction, always retaining the unique DNA amplification sequence from the original A/T-mediated duplication for that parasite line. Pseudo-polyploidy at relevant genomic loci sets the stage for gaining additional mutations at the locus of interest. Overall, we reveal a population-based genomic strategy for mutagenesis that operates in human stages of P. falciparum to efficiently yield resistance-causing genetic changes at the correct locus in a successful parasite. Importantly, these founding events arise with precision; no other new amplifications are seen in the resistant haploid blood stage parasite. This minimizes the need for meiotic genetic cleansing that can only occur in sexual stage development of the parasite in mosquitoes.

  11. Nuclear techniques in plant pathology 1. Plant disease control and physiology of parasitism

    International Nuclear Information System (INIS)

    Menten, J.O.M.; Ando, A.; Tulmann Neto, A.

    1986-01-01

    Nuclear techniques are advantageously used in several areas of plant pathology. Among them are: induction of mutation for disease resistance, studies with pesticides, disease control through pathogen inactivation, induction of variability and stimulation in pathogens and natural enemies, studies of microorganism physiology and diseased plant physiology, effect of gamma radiation on pesticides, technology of pesticides application, etc. (Author) [pt

  12. Cell Death of Gamma Interferon-Stimulated Human Fibroblasts upon Toxoplasma gondii Infection Induces Early Parasite Egress and Limits Parasite Replication

    NARCIS (Netherlands)

    Niedelman, Wendy; Sprokholt, Joris K.; Clough, Barbara; Frickel, Eva-Maria; Saeij, Jeroen P. J.

    2013-01-01

    The intracellular protozoan parasite Toxoplasma gondii is a major food-borne illness and opportunistic infection for the immunosuppressed. Resistance to Toxoplasma is dependent on gamma interferon (IFN-γ) activation of both hematopoietic and nonhematopoietic cells. Although IFN-γ-induced innate

  13. Cell death of gamma interferon-stimulated human fibroblasts upon toxoplasma gondii infection induces early parasite egress and limits parasite replication

    NARCIS (Netherlands)

    Niedelman, W.; Sprokholt, J.K.; Clough, B.; Frickel, E.; Saeij, J.P.J.

    2013-01-01

    The intracellular protozoan parasite Toxoplasma gondii is a major food-borne illness and opportunistic infection for the immunosuppressed. Resistance to Toxoplasma is dependent on gamma interferon (IFN-¿) activation of both hematopoietic and nonhematopoietic cells. Although IFN-¿-induced innate

  14. Parasites: Water

    Science.gov (United States)

    ... Consultations, and General Public. Contact Us Parasites Home Water Language: English Español (Spanish) Recommend on Facebook Tweet Share Compartir Parasites can live in natural water sources. When outdoors, treat your water before drinking ...

  15. The Plasmodium PHIST and RESA-Like Protein Families of Human and Rodent Malaria Parasites

    Science.gov (United States)

    Moreira, Cristina K.; Naissant, Bernina; Coppi, Alida; Bennett, Brandy L.; Aime, Elena; Franke-Fayard, Blandine; Janse, Chris J.; Coppens, Isabelle; Sinnis, Photini; Templeton, Thomas J.

    2016-01-01

    The phist gene family has members identified across the Plasmodium genus, defined by the presence of a domain of roughly 150 amino acids having conserved aromatic residues and an all alpha-helical structure. The family is highly amplified in P. falciparum, with 65 predicted genes in the genome of the 3D7 isolate. In contrast, in the rodent malaria parasite P. berghei 3 genes are identified, one of which is an apparent pseudogene. Transcripts of the P. berghei phist genes are predominant in schizonts, whereas in P. falciparum transcript profiles span different asexual blood stages and gametocytes. We pursued targeted disruption of P. berghei phist genes in order to characterize a simplistic model for the expanded phist gene repertoire in P. falciparum. Unsuccessful attempts to disrupt P. berghei PBANKA_114540 suggest that this phist gene is essential, while knockout of phist PBANKA_122900 shows an apparent normal progression and non-essential function throughout the life cycle. Epitope-tagging of P. falciparum and P. berghei phist genes confirmed protein export to the erythrocyte cytoplasm and localization with a punctate pattern. Three P. berghei PEXEL/HT-positive exported proteins exhibit at least partial co-localization, in support of a common vesicular compartment in the cytoplasm of erythrocytes infected with rodent malaria parasites. PMID:27022937

  16. Automation Diagnosis of Skin Disease in Humans using Dempster-Shafer Method

    Science.gov (United States)

    Khairina, Dyna Marisa; Hatta, Heliza Rahmania; Rustam; Maharani, Septya

    2018-02-01

    Skin disease is an infectious disease that is common in people of all ages. Disorders of the skin often occur because there are factors, among others, are climate, environment, shelter, unhealthy living habits, allergies and others. Skin diseases in Indonesia are mostly caused by bacterial, fungal, parasitic, and allergies. The objective of the research is to diagnose skin diseases in humans by using the method of making decision tree then performing the search by forward chaining and calculating the probability value of Dempster-Shafer method. The results of research in the form of an automated system that can resemble an expert in diagnosing skin disease accurately and can help in overcoming the problem of skin diseases.

  17. [Diseases transmitted through water for human consumption].

    Science.gov (United States)

    Franco, E; Dentamaro, M

    2003-01-01

    The water for human consumption maintains a biological risk and can transmit diseases. The classical waterborne and the presently frequent diseases caused by protozoi Giardia and Cryptosporidium are considered and Arcobacter butzleri, a new waterborne pathogen, is described. Many measures have been adopted by institutions to ensure the quality of the drinking water. Managers and public health operators is working in order to verify the efficiency of more suitable indicators for its monitoring.

  18. Modeling human disease using organotypic cultures

    DEFF Research Database (Denmark)

    Schweiger, Pawel J; Jensen, Kim B

    2016-01-01

    animal models and in vitro cell culture systems. However, it has been exceedingly difficult to model disease at the tissue level. Since recently, the gap between cell line studies and in vivo modeling has been narrowing thanks to progress in biomaterials and stem cell research. Development of reliable 3D...... culture systems has enabled a rapid expansion of sophisticated in vitro models. Here we focus on some of the latest advances and future perspectives in 3D organoids for human disease modeling....

  19. Mouse Chromosome Engineering for Modeling Human Disease

    OpenAIRE

    van der Weyden, Louise; Bradley, Allan

    2006-01-01

    Chromosomal rearrangements occur frequently in humans and can be disease-associated or phenotypically neutral. Recent technological advances have led to the discovery of copy-number changes previously undetected by cytogenetic techniques. To understand the genetic consequences of such genomic changes, these mutations need to be modeled in experimentally tractable systems. The mouse is an excellent organism for this analysis because of its biological and genetic similarity to humans, and the e...

  20. Molecular basis of Trypanosoma cruzi and Leishmania interaction with their host(s): exploitation of immune and defense mechanisms by the parasite leading to persistence and chronicity, features reminiscent of immune system evasion strategies in cancer diseases.

    Science.gov (United States)

    Ouaissi, Ali; Ouaissi, Mehdi

    2005-01-01

    A number of features occurring during host-parasite interactions in Chagas disease caused by the protozoan parasite, Trypanosoma cruzi, and Leishmaniasis, caused by a group of kinetoplastid protozoan parasites are reminiscent of those observed in cancer diseases. In fact,although the cancer is not a single disease, and that T.cruzi and Leishmania are sophisticated eukaryotic parasites presenting a high level of genotypic variability the growth of the parasites in their host and that of cancer cells share at least one common feature, that is their mutual capacity for rapid cell division. Surprisingly, the parasitic diseases and cancers share some immune evasion strategies. Consideration of these immunological alterations must be added to the evaluation of the pathogenic processes. The molecular and functional characterization of virulence factors and the study of their effect on the arms of the immune system have greatly improved understanding of the regulation of immune effectors functions. The purpose of this review is to analyze some of the current data related to the regulatory components or processes originating from the parasite that control or interfere with host cell physiology. Attempts are also made to delineate some similarities between the immune evasion strategies that parasites and tumors employ. The elucidation of the mode of action of parasite virulence factors toward the host cell allow not only provide us with a more comprehensive view of the host-parasite relationships but may also represent a step forward in efforts aimed to identify new target molecules for therapeutic intervention.

  1. Crystallization and preliminary crystallographic analysis of orotidine 5′-monophosphate decarboxylase from the human malaria parasite Plasmodium falciparum

    International Nuclear Information System (INIS)

    Krungkrai, Sudaratana R.; Tokuoka, Keiji; Kusakari, Yukiko; Inoue, Tsuyoshi; Adachi, Hiroaki; Matsumura, Hiroyoshi; Takano, Kazufumi; Murakami, Satoshi; Mori, Yusuke; Kai, Yasushi; Krungkrai, Jerapan; Horii, Toshihiro

    2006-01-01

    Orotidine 5′-monophosphate decarboxylase of human malaria parasite P. falciparum was crystallized by the seeding method in a hanging drop using PEG 3000 as a precipitant. A complete set of diffraction data from a native crystal was collected to 2.7 Å resolution at 100 K using synchrotron radiation. Orotidine 5′-monophosphate (OMP) decarboxylase (OMPDC; EC 4.1.1.23) catalyzes the final step in the de novo synthesis of uridine 5′-monophosphate (UMP) and defects in the enzyme are lethal in the malaria parasite Plasmodium falciparum. Active recombinant P. falciparum OMPDC (PfOMPDC) was crystallized by the seeding method in a hanging drop using PEG 3000 as a precipitant. A complete set of diffraction data from a native crystal was collected to 2.7 Å resolution at 100 K using synchrotron radiation at the Swiss Light Source. The crystal exhibits trigonal symmetry (space group R3), with hexagonal unit-cell parameters a = b = 201.81, c = 44.03 Å. With a dimer in the asymmetric unit, the solvent content is 46% (V M = 2.3 Å 3 Da −1 )

  2. The neurotropic parasite Toxoplasma gondii increases dopamine metabolism.

    Directory of Open Access Journals (Sweden)

    Emese Prandovszky

    Full Text Available The highly prevalent parasite Toxoplasma gondii manipulates its host's behavior. In infected rodents, the behavioral changes increase the likelihood that the parasite will be transmitted back to its definitive cat host, an essential step in completion of the parasite's life cycle. The mechanism(s responsible for behavioral changes in the host is unknown but two lines of published evidence suggest that the parasite alters neurotransmitter signal transduction: the disruption of the parasite-induced behavioral changes with medications used to treat psychiatric disease (specifically dopamine antagonists and identification of a tyrosine hydroxylase encoded in the parasite genome. In this study, infection of mammalian dopaminergic cells with T. gondii enhanced the levels of K+-induced release of dopamine several-fold, with a direct correlation between the number of infected cells and the quantity of dopamine released. Immunostaining brain sections of infected mice with dopamine antibody showed intense staining of encysted parasites. Based on these analyses, T. gondii orchestrates a significant increase in dopamine metabolism in neural cells. Tyrosine hydroxylase, the rate-limiting enzyme for dopamine synthesis, was also found in intracellular tissue cysts in brain tissue with antibodies specific for the parasite-encoded tyrosine hydroxylase. These observations provide a mechanism for parasite-induced behavioral changes. The observed effects on dopamine metabolism could also be relevant in interpreting reports of psychobehavioral changes in toxoplasmosis-infected humans.

  3. Host-seeking behaviors of mosquitoes experimentally infected with sympatric field isolates of the human malaria parasite Plasmodium falciparum: no evidence for host manipulation

    Directory of Open Access Journals (Sweden)

    Amélie eVantaux

    2015-08-01

    Full Text Available Previous studies have shown that Plasmodium parasites can manipulate mosquito feeding behaviours such as motivation and avidity to feed on vertebrate hosts, in ways that increase the probability of parasite transmission. These studies, however, have been mainly carried out on non-natural and/or laboratory based model systems and hence may not reflect what occurs in the field. We now need to move closer to the natural setting, if we are to fully capture the ecological and evolutionary consequences of these parasite-induced behavioral changes. As part of this effort, we conducted a series of experiments to investigate the long and short-range behavioural responses to human stimuli in the mosquito Anopheles coluzzii during different stages of infection with sympatric field isolates of the human malaria parasite Plasmodium falciparum in Burkina Faso. First, we used a dual-port olfactometer designed to take advantage of the whole body odor to gauge mosquito long-range host-seeking behaviors. Second, we used a locomotor activity monitor system to assess mosquito short-range behaviors. Compared to control uninfected mosquitoes, P. falciparum infection had no significant effect neither on long-range nor on short-range behaviors both at the immature and mature stages. This study, using a natural mosquito-malaria parasite association, indicates that manipulation of vector behavior may not be a general phenomenon. We speculate that the observed contrasting phenotypes with model systems might result from coevolution of the human parasite and its natural vector. Future experiments, using other sympatric malaria mosquito populations or species are required to test this hypothesis. In conclusion, our results highlight the importance of following up discoveries in laboratory model systems with studies on natural parasite–mosquito interactions to accurately predict the epidemiological, ecological and evolutionary consequences of parasite manipulation of vector

  4. Immunotherapy of Human Papilloma Virus Induced Disease

    Science.gov (United States)

    van der Burg, Sjoerd H

    2012-01-01

    Immunotherapy is the generic name for treatment modalities aiming to reinforce the immune system against diseases in which the immune system plays a role. The design of an optimal immunotherapeutic treatment against chronic viruses and associated diseases requires a detailed understanding of the interactions between the target virus and its host, in order to define the specific strategies that may have the best chance to deliver success at each stage of disease. Recently, a first series of successes was reported for the immunotherapy of Human Papilloma Virus (HPV)-induced premalignant diseases but there is definitely room for improvement. Here I discuss a number of topics that in my opinion require more study as the answers to these questions allows us to better understand the underlying mechanisms of disease and as such to tailor treatment. PMID:23341861

  5. Can Neglected Tropical Diseases Compromise Human Wellbeing in Sex-, Age-, and Trait-Specific Ways?

    Directory of Open Access Journals (Sweden)

    David C Geary

    2016-04-01

    Full Text Available Traits that facilitate competition for reproductive resources or that influence mate choice have evolved to signal resilience to infectious disease and other stressors. As a result, the dynamics of competition and choice can, in theory, be used to generate predictions about sex-, age-, and trait-specific vulnerabilities for any sexually reproducing species, including humans. These dynamics and associated vulnerabilities are reviewed for nonhuman species, focusing on traits that are compromised by exposure to parasites. Using the same approach, sex-, age-, and trait-specific vulnerabilities to parasitic disease are illustrated for children's and adolescent's physical growth and fitness. Suggestions are then provided for widening the assessment of human vulnerabilities to include age-appropriate measures of behavioral (e.g., children's play and cognitive (e.g., language fluency traits. These are traits that are likely to be compromised by infection in age- and sex-specific ways. Inclusion of these types of measures in studies of neglected tropic diseases has the potential to provide a more nuanced understanding of how these diseases undermine human wellbeing and may provide a useful means to study the efficacy of associated treatments.

  6. Human infectious diseases and risk of preeclampsia: an updated review of the literature.

    Science.gov (United States)

    Nourollahpour Shiadeh, Malihe; Behboodi Moghadam, Zahra; Adam, Ishag; Saber, Vafa; Bagheri, Maryam; Rostami, Ali

    2017-10-01

    Preeclampsia (PE) is one of the major causes of maternal and perinatal morbidity and mortality, especially in low- and middle-income countries. In recent years, a growing body of literatures suggests that infections by bacteria, viruses, and parasites and their related inflammations play an important role in the pathogenesis of PE. We searched PubMed, Google scholar, and Cochrane databases using the following search words: "infection and preeclampsia," "bacterial infection and preeclampsia," "viral infection and preeclampsia" and "parasitic infection and preeclampsia." The literature review revealed that many bacteria including Helicobacter pylori, Chlamydia pneumonia, and those are involved in periodontal disease or urinary tract infections (UTIs) and some viral agents such as Cytomegalovirus, herpes simplex virus type-2, human immunodeficiency virus, and some parasites especially Plasmodium spp. and Toxoplasma gondii can be effective in development of PE. Inflammation responses against infections has major role in the inducement of PE. The shift of immunological cytokine profile of Th2 toward Th1 and high levels of pro-inflammatory cytokines (TNF-ɑ, IL-12, IFN-γ, etc.), increase of oxidative stress, increase of anti-angiogenic proteins, increase of vascular endothelial growth factor receptor 1 (sVEGFR1), and complement C5a are the main potential mechanisms related to infections and enhanced development of PE. Thus, early diagnosis and treatment of bacterial, viral, and parasitic infections could be an effective strategy to reduce the incidence of PE.

  7. Diversity and prevalence of gastrointestinal parasites in seven non-human primates of the Taï National Park, Côte d’Ivoire

    Directory of Open Access Journals (Sweden)

    Kouassi Roland Yao Wa

    2015-01-01

    Full Text Available Parasites and infectious diseases are well-known threats to primate populations. The main objective of this study was to provide baseline data on fecal parasites in the cercopithecid monkeys inhabiting Côte d’Ivoire’s Taï National Park. Seven of eight cercopithecid species present in the park were sampled: Cercopithecus diana, Cercopithecus campbelli, Cercopithecus petaurista, Procolobus badius, Procolobus verus, Colobus polykomos, and Cercocebus atys. We collected 3142 monkey stool samples between November 2009 and December 2010. Stool samples were processed by direct wet mount examination, formalin-ethyl acetate concentration, and MIF (merthiolate, iodine, formalin concentration methods. Slides were examined under microscope and parasite identification was based on the morphology of cysts, eggs, and adult worms. A total of 23 species of parasites was recovered including 9 protozoa (Entamoeba coli, Entamoeba histolytica/dispar, Entamoeba hartmanni, Endolimax nana, Iodamoeba butschlii, Chilomastix mesnili, Giardia sp., Balantidium coli, and Blastocystis sp., 13 nematodes (Oesophagostomum sp., Ancylostoma sp., Anatrichosoma sp., Capillariidae Gen. sp. 1, Capillariidae Gen. sp. 2, Chitwoodspirura sp., Subulura sp., spirurids [cf Protospirura muricola], Ternidens sp., Strongyloides sp., Trichostrongylus sp., and Trichuris sp., and 1 trematode (Dicrocoelium sp.. Diversity indices and parasite richness were high for all monkey taxa, but C. diana, C. petaurista, C. atys, and C. campbelli exhibited a greater diversity of parasite species and a more equitable distribution. The parasitological data reported are the first available for these cercopithecid species within Taï National Park.

  8. Diversity and prevalence of gastrointestinal parasites in seven non-human primates of the Taï National Park, Côte d'Ivoire.

    Science.gov (United States)

    Kouassi, Roland Yao Wa; McGraw, Scott William; Yao, Patrick Kouassi; Abou-Bacar, Ahmed; Brunet, Julie; Pesson, Bernard; Bonfoh, Bassirou; N'goran, Eliezer Kouakou; Candolfi, Ermanno

    2015-01-01

    Parasites and infectious diseases are well-known threats to primate populations. The main objective of this study was to provide baseline data on fecal parasites in the cercopithecid monkeys inhabiting Côte d'Ivoire's Taï National Park. Seven of eight cercopithecid species present in the park were sampled: Cercopithecus diana, Cercopithecus campbelli, Cercopithecus petaurista, Procolobus badius, Procolobus verus, Colobus polykomos, and Cercocebus atys. We collected 3142 monkey stool samples between November 2009 and December 2010. Stool samples were processed by direct wet mount examination, formalin-ethyl acetate concentration, and MIF (merthiolate, iodine, formalin) concentration methods. Slides were examined under microscope and parasite identification was based on the morphology of cysts, eggs, and adult worms. A total of 23 species of parasites was recovered including 9 protozoa (Entamoeba coli, Entamoeba histolytica/dispar, Entamoeba hartmanni, Endolimax nana, Iodamoeba butschlii, Chilomastix mesnili, Giardia sp., Balantidium coli, and Blastocystis sp.), 13 nematodes (Oesophagostomum sp., Ancylostoma sp., Anatrichosoma sp., Capillariidae Gen. sp. 1, Capillariidae Gen. sp. 2, Chitwoodspirura sp., Subulura sp., spirurids [cf Protospirura muricola], Ternidens sp., Strongyloides sp., Trichostrongylus sp., and Trichuris sp.), and 1 trematode (Dicrocoelium sp.). Diversity indices and parasite richness were high for all monkey taxa, but C. diana, C. petaurista, C. atys, and C. campbelli exhibited a greater diversity of parasite species and a more equitable distribution. The parasitological data reported are the first available for these cercopithecid species within Taï National Park. © R.W.Y. Kouassi et al., published by EDP Sciences, 2015.

  9. Defining the protein interaction network of human malaria parasite Plasmodium falciparum

    KAUST Repository

    Ramaprasad, Abhinay

    2012-02-01

    Malaria, caused by the protozoan parasite Plasmodium falciparum, affects around 225. million people yearly and a huge international effort is directed towards combating this grave threat to world health and economic development. Considerable advances have been made in malaria research triggered by the sequencing of its genome in 2002, followed by several high-throughput studies defining the malaria transcriptome and proteome. A protein-protein interaction (PPI) network seeks to trace the dynamic interactions between proteins, thereby elucidating their local and global functional relationships. Experimentally derived PPI network from high-throughput methods such as yeast two hybrid (Y2H) screens are inherently noisy, but combining these independent datasets by computational methods tends to give a greater accuracy and coverage. This review aims to discuss the computational approaches used till date to construct a malaria protein interaction network and to catalog the functional predictions and biological inferences made from analysis of the PPI network. © 2011 Elsevier Inc.

  10. Northeast India Helminth Parasite Information Database (NEIHPID: Knowledge Base for Helminth Parasites.

    Directory of Open Access Journals (Sweden)

    Devendra Kumar Biswal

    Full Text Available Most metazoan parasites that invade vertebrate hosts belong to three phyla: Platyhelminthes, Nematoda and Acanthocephala. Many of the parasitic members of these phyla are collectively known as helminths and are causative agents of many debilitating, deforming and lethal diseases of humans and animals. The North-East India Helminth Parasite Information Database (NEIHPID project aimed to document and characterise the spectrum of helminth parasites in the north-eastern region of India, providing host, geographical distribution, diagnostic characters and image data. The morphology-based taxonomic data are supplemented with information on DNA sequences of nuclear, ribosomal and mitochondrial gene marker regions that aid in parasite identification. In addition, the database contains raw next generation sequencing (NGS data for 3 foodborne trematode parasites, with more to follow. The database will also provide study material for students interested in parasite biology. Users can search the database at various taxonomic levels (phylum, class, order, superfamily, family, genus, and species, or by host, habitat and geographical location. Specimen collection locations are noted as co-ordinates in a MySQL database and can be viewed on Google maps, using Google Maps JavaScript API v3. The NEIHPID database has been made freely available at http://nepiac.nehu.ac.in/index.php.

  11. Northeast India Helminth Parasite Information Database (NEIHPID): Knowledge Base for Helminth Parasites.

    Science.gov (United States)

    Biswal, Devendra Kumar; Debnath, Manish; Kharumnuid, Graciously; Thongnibah, Welfrank; Tandon, Veena

    2016-01-01

    Most metazoan parasites that invade vertebrate hosts belong to three phyla: Platyhelminthes, Nematoda and Acanthocephala. Many of the parasitic members of these phyla are collectively known as helminths and are causative agents of many debilitating, deforming and lethal diseases of humans and animals. The North-East India Helminth Parasite Information Database (NEIHPID) project aimed to document and characterise the spectrum of helminth parasites in the north-eastern region of India, providing host, geographical distribution, diagnostic characters and image data. The morphology-based taxonomic data are supplemented with information on DNA sequences of nuclear, ribosomal and mitochondrial gene marker regions that aid in parasite identification. In addition, the database contains raw next generation sequencing (NGS) data for 3 foodborne trematode parasites, with more to follow. The database will also provide study material for students interested in parasite biology. Users can search the database at various taxonomic levels (phylum, class, order, superfamily, family, genus, and species), or by host, habitat and geographical location. Specimen collection locations are noted as co-ordinates in a MySQL database and can be viewed on Google maps, using Google Maps JavaScript API v3. The NEIHPID database has been made freely available at http://nepiac.nehu.ac.in/index.php.

  12. Northeast India Helminth Parasite Information Database (NEIHPID): Knowledge Base for Helminth Parasites

    Science.gov (United States)

    Debnath, Manish; Kharumnuid, Graciously; Thongnibah, Welfrank; Tandon, Veena

    2016-01-01

    Most metazoan parasites that invade vertebrate hosts belong to three phyla: Platyhelminthes, Nematoda and Acanthocephala. Many of the parasitic members of these phyla are collectively known as helminths and are causative agents of many debilitating, deforming and lethal diseases of humans and animals. The North-East India Helminth Parasite Information Database (NEIHPID) project aimed to document and characterise the spectrum of helminth parasites in the north-eastern region of India, providing host, geographical distribution, diagnostic characters and image data. The morphology-based taxonomic data are supplemented with information on DNA sequences of nuclear, ribosomal and mitochondrial gene marker regions that aid in parasite identification. In addition, the database contains raw next generation sequencing (NGS) data for 3 foodborne trematode parasites, with more to follow. The database will also provide study material for students interested in parasite biology. Users can search the database at various taxonomic levels (phylum, class, order, superfamily, family, genus, and species), or by host, habitat and geographical location. Specimen collection locations are noted as co-ordinates in a MySQL database and can be viewed on Google maps, using Google Maps JavaScript API v3. The NEIHPID database has been made freely available at http://nepiac.nehu.ac.in/index.php PMID:27285615

  13. Reduced penetrance in human inherited disease

    African Journals Online (AJOL)

    Rabah M. Shawky

    2014-01-31

    Jan 31, 2014 ... tant role in cellular senescence, tumorigenesis and in several diseases including type ... between epigenetic DNA modifications and human life span has also been shown .... penetrance mutation that is age dependent especially when compared with the ..... on healthy aging and longevity. Immunity Aging ...

  14. Primatology. Human diseases threaten great apes.

    Science.gov (United States)

    Ferber, D

    2000-08-25

    Researchers are uncovering disturbing evidence that scientists and tourists are infecting wild primates with human pathogens. In response, ape specialists, including the American Society of Primatologists, are now calling for stricter health standards for researchers and tourists. They are also urging researchers to learn how to diagnose disease in their study animals.

  15. Parasites and immunotherapy: with or against?

    Science.gov (United States)

    Yousofi Darani, Hossein; Yousefi, Morteza; Safari, Marzieh; Jafari, Rasool

    2016-06-01

    Immunotherapy is a sort of therapy in which antibody or antigen administrates to the patient in order to treat or reduce the severity of complications of disease. This kind of treatment practiced in a wide variety of diseases including infectious diseases, autoimmune disorders, cancers and allergy. Successful and unsuccessful immunotherapeutic strategies have been practiced in variety of parasitic infections. On the other hand parasites or parasite antigens have also been considered for immunotherapy against other diseases such as cancer, asthma and multiple sclerosis. In this paper immunotherapy against common parasitic infections, and also immunotherapy of cancer, asthma and multiple sclerosis with parasites or parasite antigens have been reviewed.

  16. Sexual reproduction and genetic exchange in parasitic protists.

    Science.gov (United States)

    Weedall, Gareth D; Hall, Neil

    2015-02-01

    A key part of the life cycle of an organism is reproduction. For a number of important protist parasites that cause human and animal disease, their sexuality has been a topic of debate for many years. Traditionally, protists were considered to be primitive relatives of the 'higher' eukaryotes, which may have diverged prior to the evolution of sex and to reproduce by binary fission. More recent views of eukaryotic evolution suggest that sex, and meiosis, evolved early, possibly in the common ancestor of all eukaryotes. However, detecting sex in these parasites is not straightforward. Recent advances, particularly in genome sequencing technology, have allowed new insights into parasite reproduction. Here, we review the evidence on reproduction in parasitic protists. We discuss protist reproduction in the light of parasitic life cycles and routes of transmission among hosts.

  17. Emerging arboviral human diseases in Southern Europe.

    Science.gov (United States)

    Papa, Anna

    2017-08-01

    Southern Europe is characterized by unique landscape and climate which attract tourists, but also arthropod vectors, some of them carrying pathogens. Among several arboviral diseases that emerged in the region during the last decade, West Nile fever accounted for high number of human cases and fatalities, while Crimean-Congo hemorrhagic fever expanded its geographic distribution, and is considered as a real threat for Europe. Viruses evolve rapidly and acquire mutations making themselves stronger and naive populations more vulnerable. In an effort to tackle efficiently the emerging arboviral diseases, preparedness and strategic surveillance are needed for the early detection of the pathogen and containment and mitigation of probable outbreaks. In this review, the main human arboviral diseases that emerged in Southern Europe are described. © 2017 Wiley Periodicals, Inc.

  18. LIBP-Pred: web server for lipid binding proteins using structural network parameters; PDB mining of human cancer biomarkers and drug targets in parasites and bacteria.

    Science.gov (United States)

    González-Díaz, Humberto; Munteanu, Cristian R; Postelnicu, Lucian; Prado-Prado, Francisco; Gestal, Marcos; Pazos, Alejandro

    2012-03-01

    Lipid-Binding Proteins (LIBPs) or Fatty Acid-Binding Proteins (FABPs) play an important role in many diseases such as different types of cancer, kidney injury, atherosclerosis, diabetes, intestinal ischemia and parasitic infections. Thus, the computational methods that can predict LIBPs based on 3D structure parameters became a goal of major importance for drug-target discovery, vaccine design and biomarker selection. In addition, the Protein Data Bank (PDB) contains 3000+ protein 3D structures with unknown function. This list, as well as new experimental outcomes in proteomics research, is a very interesting source to discover relevant proteins, including LIBPs. However, to the best of our knowledge, there are no general models to predict new LIBPs based on 3D structures. We developed new Quantitative Structure-Activity Relationship (QSAR) models based on 3D electrostatic parameters of 1801 different proteins, including 801 LIBPs. We calculated these electrostatic parameters with the MARCH-INSIDE software and they correspond to the entire protein or to specific protein regions named core, inner, middle, and surface. We used these parameters as inputs to develop a simple Linear Discriminant Analysis (LDA) classifier to discriminate 3D structure of LIBPs from other proteins. We implemented this predictor in the web server named LIBP-Pred, freely available at , along with other important web servers of the Bio-AIMS portal. The users can carry out an automatic retrieval of protein structures from PDB or upload their custom protein structural models from their disk created with LOMETS server. We demonstrated the PDB mining option performing a predictive study of 2000+ proteins with unknown function. Interesting results regarding the discovery of new Cancer Biomarkers in humans or drug targets in parasites have been discussed here in this sense.

  19. The activities of current antimalarial drugs on the life cycle stages of Plasmodium: a comparative study with human and rodent parasites.

    Science.gov (United States)

    Delves, Michael; Plouffe, David; Scheurer, Christian; Meister, Stephan; Wittlin, Sergio; Winzeler, Elizabeth A; Sinden, Robert E; Leroy, Didier

    2012-02-01

    Malaria remains a disease of devastating global impact, killing more than 800,000 people every year-the vast majority being children under the age of 5. While effective therapies are available, if malaria is to be eradicated a broader range of small molecule therapeutics that are able to target the liver and the transmissible sexual stages are required. These new medicines are needed both to meet the challenge of malaria eradication and to circumvent resistance. Little is known about the wider stage-specific activities of current antimalarials that were primarily designed to alleviate symptoms of malaria in the blood stage. To overcome this critical gap, we developed assays to measure activity of antimalarials against all life stages of malaria parasites, using a diverse set of human and nonhuman parasite species, including male gamete production (exflagellation) in Plasmodium falciparum, ookinete development in P. berghei, oocyst development in P. berghei and P. falciparum, and the liver stage of P. yoelii. We then compared 50 current and experimental antimalarials in these assays. We show that endoperoxides such as OZ439, a stable synthetic molecule currently in clinical phase IIa trials, are strong inhibitors of gametocyte maturation/gamete formation and impact sporogony; lumefantrine impairs development in the vector; and NPC-1161B, a new 8-aminoquinoline, inhibits sporogony. These data enable objective comparisons of the strengths and weaknesses of each chemical class at targeting each stage of the lifecycle. Noting that the activities of many compounds lie within achievable blood concentrations, these results offer an invaluable guide to decisions regarding which drugs to combine in the next-generation of antimalarial drugs. This study might reveal the potential of life-cycle-wide analyses of drugs for other pathogens with complex life cycles.

  20. The Activities of Current Antimalarial Drugs on the Life Cycle Stages of Plasmodium: A Comparative Study with Human and Rodent Parasites

    Science.gov (United States)

    Delves, Michael; Plouffe, David; Scheurer, Christian; Meister, Stephan; Wittlin, Sergio; Winzeler, Elizabeth A.; Sinden, Robert E.; Leroy, Didier

    2012-01-01

    Background Malaria remains a disease of devastating global impact, killing more than 800,000 people every year—the vast majority being children under the age of 5. While effective therapies are available, if malaria is to be eradicated a broader range of small molecule therapeutics that are able to target the liver and the transmissible sexual stages are required. These new medicines are needed both to meet the challenge of malaria eradication and to circumvent resistance. Methods and Findings Little is known about the wider stage-specific activities of current antimalarials that were primarily designed to alleviate symptoms of malaria in the blood stage. To overcome this critical gap, we developed assays to measure activity of antimalarials against all life stages of malaria parasites, using a diverse set of human and nonhuman parasite species, including male gamete production (exflagellation) in Plasmodium falciparum, ookinete development in P. berghei, oocyst development in P. berghei and P. falciparum, and the liver stage of P. yoelii. We then compared 50 current and experimental antimalarials in these assays. We show that endoperoxides such as OZ439, a stable synthetic molecule currently in clinical phase IIa trials, are strong inhibitors of gametocyte maturation/gamete formation and impact sporogony; lumefantrine impairs development in the vector; and NPC-1161B, a new 8-aminoquinoline, inhibits sporogony. Conclusions These data enable objective comparisons of the strengths and weaknesses of each chemical class at targeting each stage of the lifecycle. Noting that the activities of many compounds lie within achievable blood concentrations, these results offer an invaluable guide to decisions regarding which drugs to combine in the next-generation of antimalarial drugs. This study might reveal the potential of life-cycle–wide analyses of drugs for other pathogens with complex life cycles. Please see later in the article for the Editors' Summary PMID

  1. One Health: parasites and beyond.

    Science.gov (United States)

    Blake, Damer P; Betson, Martha

    2017-01-01

    The field of parasitism is broad, encompassing relationships between organisms where one benefits at the expense of another. Traditionally the discipline focuses on eukaryotes, with the study of bacteria and viruses complementary but distinct. Nonetheless, parasites vary in size and complexity from single celled protozoa, to enormous plants like those in the genus Rafflesia. Lifecycles range from obligate intracellular to extensive exoparasitism. Examples of parasites include high-profile medical and zoonotic pathogens such as Plasmodium, veterinary pathogens of wild and captive animals and many of the agents which cause neglected tropical diseases, stretching to parasites which infect plants and other parasites (e.g. Kikuchi et al. 2011; Hotez et al. 2014; Blake et al. 2015; Hemingway, 2015; Meekums et al. 2015; Sandlund et al. 2015). The breadth of parasitology has been matched by the variety of ways in which parasites are studied, drawing upon biological, chemical, molecular, epidemiological and other expertise. Despite such breadth bridging between disciplines has commonly been problematic, regardless of extensive encouragement from government agencies, peer audiences and funding bodies promoting multidisciplinary research. Now, progress in understanding and collaboration can benefit from establishment of the One Health concept (Zinsstag et al. 2012; Stark et al. 2015). One Health draws upon biological, environmental, medical, veterinary and social science disciplines in order to improve human, animal and environmental health, although it remains tantalizingly difficult to engage many relevant parties. For infectious diseases traditional divides have been exacerbated as the importance of wildlife reservoirs, climate change, food production systems and socio-economic diversity have been recognized but often not addressed in a multidisciplinary manner. In response the 2015 Autumn Symposium organized by the British Society for Parasitology (BSP; https

  2. Risk factors for gastrointestinal parasite infections of dogs living around protected areas of the Atlantic Forest: implications for human and wildlife health.

    Science.gov (United States)

    Curi, N H A; Paschoal, A M O; Massara, R L; Santos, H A; Guimarães, M P; Passamani, M; Chiarello, A G

    2017-01-01

    Despite the ubiquity of domestic dogs, their role as zoonotic reservoirs and the large number of studies concerning parasites in urban dogs, rural areas in Brazil, especially those at the wildlife-domestic animal-human interface, have received little attention from scientists and public health managers. This paper reports a cross-sectional epidemiological survey of gastrointestinal parasites of rural dogs living in farms around Atlantic Forest fragments. Through standard parasitological methods (flotation and sedimentation), 13 parasite taxa (11 helminths and two protozoans) were found in feces samples from dogs. The most prevalent were the nematode Ancylostoma (47%) followed by Toxocara (18%) and Trichuris (8%). Other less prevalent (dogs younger than one year were more likely to be infected with Toxocara, and purebred dogs with Trichuris. The number of cats in the households was positively associated with Trichuris infection, while male dogs and low body scores were associated with mixed infections. The lack of associations with dog free-ranging behavior and access to forest or villages indicates that infections are mostly acquired around the households. The results highlight the risk of zoonotic and wildlife parasite infections from dogs and the need for monitoring and controlling parasites of domestic animals in human-wildlife interface areas.

  3. How do humans affect wildlife nematodes?

    Science.gov (United States)

    Weinstein, Sara B.; Lafferty, Kevin D.

    2015-01-01

    Human actions can affect wildlife and their nematode parasites. Species introductions and human-facilitated range expansions can create new host–parasite interactions. Novel hosts can introduce parasites and have the potential to both amplify and dilute nematode transmission. Furthermore, humans can alter existing nematode dynamics by changing host densities and the abiotic conditions that affect larval parasite survival. Human impacts on wildlife might impair parasites by reducing the abundance of their hosts; however, domestic animal production and complex life cycles can maintain transmission even when wildlife becomes rare. Although wildlife nematodes have many possible responses to human actions, understanding host and parasite natural history, and the mechanisms behind the changing disease dynamics might improve disease control in the few cases where nematode parasitism impacts wildlife.

  4. The Ecology of Parasite-Host Interactions at Montezuma Well National Monument, Arizona - Appreciating the Importance of Parasites

    Science.gov (United States)

    O'Brien, Chris; van Riper, Charles

    2009-01-01

    Although parasites play important ecological roles through the direct interactions they have with their hosts, historically that fact has been underappreciated. Today, scientists have a growing appreciation of the scope of such impacts. Parasites have been reported to dominate food webs, alter predator-prey relationships, act as ecosystem engineers, and alter community structure. In spite of this growing awareness in the scientific community, parasites are still often neglected in the consideration of the management and conservation of resources and ecosystems. Given that at least half of the organisms on earth are probably parasitic, it should be evident that the ecological functions of parasites warrant greater attention. In this report, we explore different aspects of parasite-host relationships found at a desert spring pond within Montezuma Well National Monument, Arizona. In three separate but related chapters, we explore interactions between a novel amphipod host and two parasites. First, we identify how host behavior responds to this association and how this association affects interactions with both invertebrate non-host predators and a vertebrate host predator. Second, we look at the human dimension, investigating how human recreation can indirectly affect patterns of disease by altering patterns of vertebrate host space use. Finally - because parasites and diseases are of increasing importance in the management of wildlife species, especially those that are imperiled or of management concern - the third chapter argues that research would benefit from increased attention to the statistical analysis of wildlife disease studies. This report also explores issues of statistical parasitology, providing information that may better inform those designing research projects and analyzing data from studies of wildlife disease. In investigating the nature of parasite-host interactions, the role that relationships play in ecological communities, and how human

  5. Role of parasites in cancer.

    Science.gov (United States)

    Mandong, B M; Ngbea, J A; Raymond, Vhriterhire

    2013-01-01

    In areas of parasitic endemicity, the occurrence of cancer that is not frequent may be linked with parasitic infection. Epidemiological correlates between some parasitic infections and cancer is strong, suggesting a strong aetiological association. The common parasites associated with human cancers are schistosomiasis, malaria, liver flukes (Clonorchis sinenses, Opistorchis viverrini). To review the pathology, literature and methods of diagnosis. Literature review from peer reviewed Journals cited in PubMed and local journals. Parasites may serve as promoters of cancer in endemic areas of infection.

  6. Human endogenous retroviruses in neurologic disease.

    Science.gov (United States)

    Christensen, Tove

    2016-01-01

    Endogenous retroviruses are pathogenic - in other species than the human. Disease associations for Human Endogenous RetroViruses (HERVs) are emerging, but so far an unequivocal pathogenetic cause-effect relationship has not been established. A role for HERVs has been proposed in neurological and neuropsychiatric diseases as diverse as multiple sclerosis (MS) and schizophrenia (SCZ). Particularly for MS, many aspects of the activation and involvement of specific HERV families (HERV-H/F and HERV-W/MSRV) have been reported, both for cells in the circulation and in the central nervous system. Notably envelope genes and their gene products (Envs) appear strongly associated with the disease. For SCZ, for ALS, and for HIV-associated dementia (HAD), indications are accumulating for involvement of the HERV-K family, and also HERV-H/F and/or HERV-W. Activation is reasonably a prerequisite for causality as most HERV sequences remain quiescent in non-pathological conditions, so the importance of regulatory pathways and epigenetics involved in regulating HERV activation, derepression, and also involvement of retroviral restriction factors, is emerging. HERV-directed antiretrovirals have potential as novel therapeutic paradigms in neurologic disease, particularly in MS. The possible protective or ameliorative effects of antiretroviral therapy in MS are substantiated by reports that treatment of HIV infection may be associated with a significantly decreased risk of MS. Further studies of HERVs, their role in neurologic diseases, and their potential as therapeutic targets are essential. © 2016 APMIS. Published by John Wiley & Sons Ltd.

  7. Glycomic Analysis of Life Stages of the Human Parasite Schistosoma mansoni Reveals Developmental Expression Profiles of Functional and Antigenic Glycan Motifs

    NARCIS (Netherlands)

    Smit, C.H.; van Diepen, A.; Nguyen, D.L.; Wuhrer, M.; Hoffmann, K.F.; Deelder, A.M.; Hokke, C.H.

    2015-01-01

    Glycans present on glycoproteins and glycolipids of the major human parasite Schistosoma mansoni induce innate as well as adaptive immune responses in the host. To be able to study the molecular characteristics of schistosome infections it is therefore required to determine the expression profiles

  8. Trypanosoma cruzi in the chicken model: Chagas-like heart disease in the absence of parasitism

    Czech Academy of Sciences Publication Activity Database

    Teixeira, A.R.L.; Gomes, C.; Nitz, N.; Sousa, A.O.; Alvez, R.M.; Guimaro, M.C.; Cordeiro, C.; Bernal, F.M.; Rosa, A.C.; Hejnar, Jiří; Leonardecz, E.; Hecht, M.M.

    2011-01-01

    Roč. 5, č. 3 (2011), e1000 ISSN 1935-2735 Institutional research plan: CEZ:AV0Z50520514 Keywords : Chagas disease * Trypanosoma cruzi * kDNA minicircles * inbred chicken Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.716, year: 2011

  9. Molecular biology of human muscle disease

    Energy Technology Data Exchange (ETDEWEB)

    Dunne, P.W.; Epstein, H.F. (Baylor Coll. of Medicine, Houston, TX (United States))

    1991-01-01

    The molecular revolution that is transforming the entire biomedical field has had far-reaching impact in its application to inherited human muscle disease. The gene for Duchenne muscular dystrophy was one of the first cloned without knowledge of the defective protein product. This success was based upon the availability of key chromosomal aberrations that provided molecular landmarks for the disease locus. Subsequent discoveries regarding the mode of expression for this gene, the structure and localization of its protein product dystrophin, and molecular diagnosis of affected and carrier individuals constitute a paradigm for investigation of human genetics. Finding the gene for myotonic muscular dystrophy is requiring the brute force approach of cloning several million bases of DNA, identifying expressed sequences, and characterizing candidate genes. The gene that causes hypertrophic cardiomyopathy has been found serendipitously to be one of the genetic markers on chromosome 14, the {beta} myosin heavy chain.

  10. The nuclear envelopathies and human diseases

    Directory of Open Access Journals (Sweden)

    Jeang Kuan-Teh

    2009-10-01

    Full Text Available Abstract The nuclear envelope (NE consists of two membrane layers that segregate the nuclear from the cytoplasmic contents. Recent progress in our understanding of nuclear-lamina associated diseases has revealed intriguing connections between the envelope components and nuclear processes. Here, we review the functions of the nuclear envelope in chromosome organization, gene expression, DNA repair and cell cycle progression, and correlate deficiencies in envelope function with human pathologies.

  11. Humanized Mouse Model of Ebola Virus Disease Mimics the Immune Responses in Human Disease.

    Science.gov (United States)

    Bird, Brian H; Spengler, Jessica R; Chakrabarti, Ayan K; Khristova, Marina L; Sealy, Tara K; Coleman-McCray, JoAnn D; Martin, Brock E; Dodd, Kimberly A; Goldsmith, Cynthia S; Sanders, Jeanine; Zaki, Sherif R; Nichol, Stuart T; Spiropoulou, Christina F

    2016-03-01

    Animal models recapitulating human Ebola virus disease (EVD) are critical for insights into virus pathogenesis. Ebola virus (EBOV) isolates derived directly from human specimens do not, without adaptation, cause disease in immunocompetent adult rodents. Here, we describe EVD in mice engrafted with human immune cells (hu-BLT). hu-BLT mice developed EVD following wild-type EBOV infection. Infection with high-dose EBOV resulted in rapid, lethal EVD with high viral loads, alterations in key human antiviral immune cytokines and chemokines, and severe histopathologic findings similar to those shown in the limited human postmortem data available. A dose- and donor-dependent clinical course was observed in hu-BLT mice infected with lower doses of either Mayinga (1976) or Makona (2014) isolates derived from human EBOV cases. Engraftment of the human cellular immune system appeared to be essential for the observed virulence, as nonengrafted mice did not support productive EBOV replication or develop lethal disease. hu-BLT mice offer a unique model for investigating the human immune response in EVD and an alternative animal model for EVD pathogenesis studies and therapeutic screening. Published by Oxford University Press for the Infectious Diseases Society of America 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  12. Impact of water supply, domiciliary water reservoirs and sewage on faeco-orally transmitted parasitic diseases in children residing in poor areas in Juiz de Fora, Brazil.

    Science.gov (United States)

    Teixeira, J C; Heller, L

    2006-08-01

    The objectives of this study were to characterize faeco-orally transmitted parasitic diseases and to identify the factors associated with these diseases, with emphasis on environmental factors, in children ranging from 1 up to 5 years old residing in substandard settlement areas. A population-based cross-sectional epidemiological design was used in a non-random selection of 29 out of the 78 substandard settlement areas in the municipality of Juiz de Fora, Brazil. A sample of 753 children were assessed from the target population consisting of all children of the appropriate age range residing in the selected areas. Data were collected by means of domiciliary interviews with their mothers or with the person responsible for them. The Hoffmann-Pons-Janer method was used in the parasitological examination of faeces. Binary logistic regression models were used to identify the factors associated with the diseases. A total of 319 sample children presented faeco-orally transmitted parasitic diseases. The factors associated with these parasitic diseases included the children's age, family income, number of dwellers in the domicile, consumption of water from shallow wells, consumption of water from natural sources, absence of covered domiciliary water reservoirs, and the presence of sewage flowing in the street.

  13. The role of chemerin in human disease

    Directory of Open Access Journals (Sweden)

    Magdalena Stojek

    2017-02-01

    Full Text Available Adipose tissue is not merely a storage depot of triacylglycerols but also a major endocrine organ. Its cells, including adipocytes, synthesize and secrete a range of biologically active molecules termed adipokines. Adipokines that display the properties of cytokines are often called adipocytokines. In recent years there has been increasing interest in a new adipokine called chemerin. Chemerin is a protein synthesized mostly by the adipose tissue and the liver as inactive pre-pro-chemerin. After the intracellular hydrolytic cutting off of the 20-amino-acid N-terminal polypeptide, it is secreted into the bloodstream as inactive pro-chemerin. Biologically active chemerin is then derived from pro-chemerin after cleavage of the C-terminal fragment by serum proteases involved in inflammation, coagulation and fibrinolysis. Proteolytic cleavage leads to formation of several chemerin-derived peptides, both biologically active (often with opposing functions and inactive.Within the last decade, there has been a growing number of publications regarding the role of chemerin in human disease. It seems to be implicated in the inflammatory response, metabolic syndrome, cardiovascular disease and alimentary tract disorders. The article presents the most recent information on the role of chemerin in human disease, and specifically alimentary tract disorders. The available evidence suggests that chemerin is an important link between adipose tissue mass, metabolic processes, the immune system and inflammation, and therefore plays a major role in human pathophysiology.

  14. Quantitative disease resistance: to better understand parasite-mediated selection on major histocompatibility complex.

    Science.gov (United States)

    Westerdahl, Helena; Asghar, Muhammad; Hasselquist, Dennis; Bensch, Staffan

    2012-02-07

    We outline a descriptive framework of how candidate alleles of the immune system associate with infectious diseases in natural populations of animals. Three kinds of alleles can be separated when both prevalence of infection and infection intensity are measured--qualitative disease resistance, quantitative disease resistance and susceptibility alleles. Our descriptive framework demonstrates why alleles for quantitative resistance and susceptibility cannot be separated based on prevalence data alone, but are distinguishable on infection intensity. We then present a case study to evaluate a previous finding of a positive association between prevalence of a severe avian malaria infection (GRW2, Plasmodium ashfordi) and a major histocompatibility complex (MHC) class I allele (B4b) in great reed warblers Acrocephalus arundinaceus. Using the same dataset, we find that individuals with allele B4b have lower GRW2 infection intensities than individuals without this allele. Therefore, allele B4b provides quantitative resistance rather than increasing susceptibility to infection. This implies that birds carrying B4b can mount an immune response that suppresses the acute-phase GRW2 infection, while birds without this allele cannot and may die. We argue that it is important to determine whether MHC alleles related to infections are advantageous (quantitative and qualitative resistance) or disadvantageous (susceptibility) to obtain a more complete picture of pathogen-mediated balancing selection.

  15. Lineage Analysis of Circulating Trypanosoma cruzi Parasites and Their Association with Clinical Forms of Chagas Disease in Bolivia

    Science.gov (United States)

    del Puerto, Ramona; Nishizawa, Juan Eiki; Kikuchi, Mihoko; Iihoshi, Naomi; Roca, Yelin; Avilas, Cinthia; Gianella, Alberto; Lora, Javier; Gutierrez Velarde, Freddy Udalrico; Renjel, Luis Alberto; Miura, Sachio; Higo, Hiroo; Komiya, Norihiro; Maemura, Koji; Hirayama, Kenji

    2010-01-01

    Background The causative agent of Chagas disease, Trypanosoma cruzi, is divided into 6 Discrete Typing Units (DTU): Tc I, IIa, IIb, IIc, IId and IIe. In order to assess the relative pathogenicities of different DTUs, blood samples from three different clinical groups of chronic Chagas disease patients (indeterminate, cardiac, megacolon) from Bolivia were analyzed for their circulating parasites lineages using minicircle kinetoplast DNA polymorphism. Methods and Findings Between 2000 and 2007, patients sent to the Centro Nacional de Enfermedades Tropicales for diagnosis of Chagas from clinics and hospitals in Santa Cruz, Bolivia, were assessed by serology, cardiology and gastro-intestinal examinations. Additionally, patients who underwent colonectomies due to Chagasic magacolon at the Hospital Universitario Japonés were also included. A total of 306 chronic Chagas patients were defined by their clinical types (81 with cardiopathy, 150 without cardiopathy, 100 with megacolon, 144 without megacolon, 164 with cardiopathy or megacolon, 73 indeterminate and 17 cases with both cardiopathy and megacolon). DNA was extracted from 10 ml of peripheral venous blood for PCR analysis. The kinetoplast minicircle DNA (kDNA) was amplified from 196 out of 306 samples (64.1%), of which 104 (53.3%) were Tc IId, 4 (2.0%) Tc I, 7 (3.6%) Tc IIb, 1 (0.5%) Tc IIe, 26 (13.3%) Tc I/IId, 1 (0.5%) Tc I/IIb/IId, 2 (1.0%) Tc IIb/d and 51 (25.9%) were unidentified. Of the 133 Tc IId samples, three different kDNA hypervariable region patterns were detected; Mn (49.6%), TPK like (48.9%) and Bug-like (1.5%). There was no significant association between Tc types and clinical manifestations of disease. Conclusions None of the identified lineages or sublineages was significantly associated with any particular clinical manifestations in the chronic Chagas patients in Bolivia. PMID:20502516

  16. Susceptibility Testing of Medically Important Parasites.

    Science.gov (United States)

    Genetu Bayih, Abebe; Debnath, Anjan; Mitre, Edward; Huston, Christopher D; Laleu, Benoît; Leroy, Didier; Blasco, Benjamin; Campo, Brice; Wells, Timothy N C; Willis, Paul A; Sjö, Peter; Van Voorhis, Wesley C; Pillai, Dylan R

    2017-07-01

    In the last 2 decades, renewed attention to neglected tropical diseases (NTDs) has spurred the development of antiparasitic agents, especially in light of emerging drug resistance. The need for new drugs has required in vitro screening methods using parasite culture. Furthermore, clinical laboratories sought to correlate in vitro susceptibility methods with treatment outcomes, most notably with malaria. Parasites with their various life cycles present greater complexity than bacteria, for which standardized susceptibility methods exist. This review catalogs the state-of-the-art methodologies used to evaluate the effects of drugs on key human parasites from the point of view of drug discovery as well as the need for laboratory methods that correlate with clinical outcomes. Copyright © 2017 American Society for Microbiology.

  17. Intestinal parasitic infections among children under five years of age presenting with diarrhoeal diseases to two public health facilities in Hawassa, South Ethiopia.

    Science.gov (United States)

    Mulatu, Getamesay; Zeynudin, Ahmed; Zemene, Endalew; Debalke, Serkadis; Beyene, Getenet

    2015-11-04

    Diarrhoea is the leading cause of morbidity and mortality in children under 5 years of age in developing countries, including Ethiopia. It is caused by a wide range of pathogens, including parasites, bacteria and viruses. The aim of this study was to determine the prevalence of infection with intestinal parasites (IPs) (and types) among children under 5 years of age with diarrhoeal diseases. A cross-sectional study was conducted at Adare Hospital and Millennium Health Centre, both located in Hawassa, South Ethiopia, from June 6 to October 28, 2011. Children under 5 years of age with diarrhoea who visited these health facilities during the study period were included in the study. Data relating to demography and risk factors associated with intestinal parasitic infections (IPIs) were gathered using a structured questionnaire. Single, fresh stool specimens were examined for IPs using the direct wet mount examination, followed by Ziehl-Neelsen staining of formol-ether concentrated samples, as per standard procedures. Data were analysed using SPSS Statistics 20 software. A total of 158 children (51.3 % male and 48.7 % female) participated in the study. Overall, the prevalence of IPs was 26.6 % (42/158). Two species of IPs were detected in six children (3.8 %). Entamoeba histolytica/dispar/moshkovskii was the predominant parasite identified (11.4 %), followed by Giardia duodenalis (7.0 %). The multivariable analysis revealed that the age group ≥24 months was significantly associated (AOR = 0.221, 95 %CI: 0.085-0.576) with prevalence of IPIs. This study found that intestinal parasites are common among children with diarrheal diseases. The most frequently detected species was E. histolytica/dispar/moshkovskii. Health information about how to prevent diarrheal diseases in general and IPIs in particular should be provided to parents of young children.

  18. A suspected parasite spill-back of two novel Myxidium spp. (Myxosporea causing disease in Australian endemic frogs found in the invasive Cane toad.

    Directory of Open Access Journals (Sweden)

    Ashlie Hartigan

    Full Text Available Infectious diseases are contributing to the decline of endangered amphibians. We identified myxosporean parasites, Myxidium spp. (Myxosporea: Myxozoa, in the brain and liver of declining native frogs, the Green and Golden Bell frog (Litoria aurea and the Southern Bell frog (Litoria raniformis. We unequivocally identified two Myxidium spp. (both generalist affecting Australian native frogs and the invasive Cane toad (Bufo marinus, syn. Rhinella marina and demonstrated their association with disease. Our study tested the identity of Myxidium spp. within native frogs and the invasive Cane toad (brought to Australia in 1935, via Hawaii to resolve the question whether the Cane toad introduced them to Australia. We showed that the Australian brain and liver Myxidium spp. differed 9%, 7%, 34% and 37% at the small subunit rDNA, large subunit rDNA, internal transcribed spacers 1 and 2, but were distinct from Myxidium cf. immersum from Cane toads in Brazil. Plotting minimum within-group distance against maximum intra-group distance confirmed their independent evolutionary trajectory. Transmission electron microscopy revealed that the brain stages localize inside axons. Myxospores were morphologically indistinguishable, therefore genetic characterisation was necessary to recognise these cryptic species. It is unlikely that the Cane toad brought the myxosporean parasites to Australia, because the parasites were not found in 261 Hawaiian Cane toads. Instead, these data support the enemy-release hypothesis predicting that not all parasites are translocated with their hosts and suggest that the Cane toad may have played an important spill-back role in their emergence and facilitated their dissemination. This work emphasizes the importance of accurate species identification of pathogens relevant to wildlife management and disease control. In our case it is paving the road for the spill-back role of the Cane toad and the parasite emergence.

  19. PREVALENCE OF INTESTINAL PARASITES AMONG FOOD HANDLERS IN WESTERN IRAN

    Directory of Open Access Journals (Sweden)

    Farnaz Kheirandish

    2014-04-01

    Full Text Available Parasitic infection is one of the problems that affect human health, especially in developing countries. In this study, all of the fast food shops, restaurants, and roast meat outlets of Khorramabad (Western Iran and all the staff employed by them, some 210 people, were selected through a census and their stools were examined for the presence of parasites. The parasitological tests of direct wet-mount, Lugol's iodine staining, formaldehyde-ether sedimentation and Trichrome staining techniques were performed on the samples. The data was analyzed with a chi-square test and logistic regression was selected as the analytical model. The results showed 19 (9% stool specimens were positive for different intestinal parasites. These intestinal parasites included Giardia lamblia2.9%, Entamoeba coli 4.3%, Blastocystis sp. 1.4%, and Hymenolepis nana 0.5%. There was a significant difference between the presence of a valid health card, awareness of transmission of intestinal parasites, participation in training courses in environmental health with intestinal parasites (p 0.05. To control parasitic infection in food handlers, several strategies are recommended such as stool examinations every three months, public education, application of health regulations, controlling the validity of health cards and training on parasitic infection transmission. In this regard, the findings of the present study can be used as a basis to develop preventive programs targeting food handlers because the spread of disease via them is a common problem worldwide.

  20. Prevalence of intestinal parasites among food handlers in Western Iran.

    Science.gov (United States)

    Kheirandish, Farnaz; Tarahi, Mohammad Javad; Ezatpour, Behrouz

    2014-01-01

    Parasitic infection is one of the problems that affect human health, especially in developing countries. In this study, all of the fast food shops, restaurants, and roast meat outlets of Khorramabad (Western Iran) and all the staff employed by them, some 210 people, were selected through a census and their stools were examined for the presence of parasites. The parasitological tests of direct wet-mount, Lugol's iodine staining, formaldehyde-ether sedimentation and Trichrome staining techniques were performed on the samples. The data was analyzed with a chi-square test and logistic regression was selected as the analytical model. The results showed 19 (9%) stool specimens were positive for different intestinal parasites. These intestinal parasites included Giardia lamblia 2.9%, Entamoeba coli 4.3%, Blastocystis sp. 1.4%, and Hymenolepis nana 0.5%. There was a significant difference between the presence of a valid health card, awareness of transmission of intestinal parasites, participation in training courses in environmental health with intestinal parasites (p 0.05). To control parasitic infection in food handlers, several strategies are recommended such as stool examinations every three months, public education, application of health regulations, controlling the validity of health cards and training on parasitic infection transmission. In this regard, the findings of the present study can be used as a basis to develop preventive programs targeting food handlers because the spread of disease via them is a common problem worldwide.

  1. Risk factors for gastrointestinal parasite infections of dogs living around protected areas of the Atlantic Forest: implications for human and wildlife health

    Directory of Open Access Journals (Sweden)

    N. H. A. Curi

    Full Text Available Abstract Despite the ubiquity of domestic dogs, their role as zoonotic reservoirs and the large number of studies concerning parasites in urban dogs, rural areas in Brazil, especially those at the wildlife-domestic animal-human interface, have received little attention from scientists and public health managers. This paper reports a cross-sectional epidemiological survey of gastrointestinal parasites of rural dogs living in farms around Atlantic Forest fragments. Through standard parasitological methods (flotation and sedimentation, 13 parasite taxa (11 helminths and two protozoans were found in feces samples from dogs. The most prevalent were the nematode Ancylostoma (47% followed by Toxocara (18% and Trichuris (8%. Other less prevalent (<2% parasites found were Capillaria, Ascaridia, Spirocerca, Taeniidae, Acantocephala, Ascaris, Dipylidium caninum, Toxascaris, and the protozoans Cystoisospora and Eimeria. Mixed infections were found in 36% of samples, mostly by Ancylostoma and Toxocara. Previous deworming had no association with infections, meaning that this preventive measure is being incorrectly performed by owners. Regarding risk factors, dogs younger than one year were more likely to be infected with Toxocara, and purebred dogs with Trichuris. The number of cats in the households was positively associated with Trichuris infection, while male dogs and low body scores were associated with mixed infections. The lack of associations with dog free-ranging behavior and access to forest or villages indicates that infections are mostly acquired around the households. The results highlight the risk of zoonotic and wildlife parasite infections from dogs and the need for monitoring and controlling parasites of domestic animals in human-wildlife interface areas.

  2. [An analysis on funded theses in the Chinese Journal of Parasitology and Parasitic Diseases in 2009-2012].

    Science.gov (United States)

    Yi, Feng-yun; Zhang, Zheng-yan; Sheng, Hui-feng

    2014-12-01

    The published articles of the Chinese Journal of Parasitology and Parasitic Diseases in 2009-2012 (including original articles, experimental researches, field researches and clinical researches) were statistically analyzed. Together 258 research papers were published in the 4 years, and funded papers occupied 82.2% (212/258). The number of papers funded by 1, 2, 3, 4, and 5 foundations projects was 116, 58, 29, 7 and 2, respectively. 61.8% (131/212) of the foundations projects were at the national level; 28.3% (60/212) were at provincial and ministerial level. The papers supported by academy and international agencies accounted for 7.1% (15/212), 2.8% (6/212), respectively. The funded thesis mainly referred to schistosomiasis (35, 16.5%), cystic echinococcosis (29, 13.7%), malaria (24, 11.3%), toxoplasmosis (22, 10.4%), and cysticercosis (9, 4.2%). Five fields covered in these papers were as follows: epidemiology (29, 13.7%), immunology and diagnosis (53, 25%), molecular biology (75, 35.4%), etiology (28,13.2%), and pharmacology (24, 11.3%). The ratio of founded paper was 0.70, 0.67, 0.74, and 0.65 during 2009-2012, respectively. The high ratio of founded paper indicated that this journal is with domestic and abroad importance in the field of parasitology.

  3. Insect Peptides - Perspectives in Human Diseases Treatment.

    Science.gov (United States)

    Chowanski, Szymon; Adamski, Zbigniew; Lubawy, Jan; Marciniak, Pawel; Pacholska-Bogalska, Joanna; Slocinska, Malgorzata; Spochacz, Marta; Szymczak, Monika; Urbanski, Arkadiusz; Walkowiak-Nowicka, Karolina; Rosinski, Grzegorz

    2017-01-01

    Insects are the largest and the most widely distributed group of animals in the world. Their diversity is a source of incredible variety of different mechanisms of life processes regulation. There are many agents that regulate immunology, reproduction, growth and development or metabolism. Hence, it seems that insects may be a source of numerous substances useful in human diseases treatment. Especially important in the regulation of insect physiology are peptides, like neuropeptides, peptide hormones or antimicrobial peptides. There are two main aspects where they can be helpful, 1) Peptides isolated from insects may become potential drugs in therapy of different diseases, 2) A lot of insect peptide hormones show structural or functional homology to mammalian peptide hormones and the comparative studies may give a new look on human disorders. In our review we focused on three group of insect derived peptides: 1) immune-active peptides, 2) peptide hormones and 3) peptides present in venoms. In our review we try to show the considerable potential of insect peptides in searching for new solutions for mammalian diseases treatment. We summarise the knowledge about properties of insect peptides against different virulent agents, anti-inflammatory or anti-nociceptive properties as well as compare insect and mammalian/vertebrate peptide endocrine system to indicate usefulness of knowledge about insect peptide hormones in drug design. The field of possible using of insect delivered peptide to therapy of various human diseases is still not sufficiently explored. Undoubtedly, more attention should be paid to insects due to searching new drugs. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  4. Human Genome Sequencing in Health and Disease

    Science.gov (United States)

    Gonzaga-Jauregui, Claudia; Lupski, James R.; Gibbs, Richard A.

    2013-01-01

    Following the “finished,” euchromatic, haploid human reference genome sequence, the rapid development of novel, faster, and cheaper sequencing technologies is making possible the era of personalized human genomics. Personal diploid human genome sequences have been generated, and each has contributed to our better understanding of variation in the human genome. We have consequently begun to appreciate the vastness of individual genetic variation from single nucleotide to structural variants. Translation of genome-scale variation into medically useful information is, however, in its infancy. This review summarizes the initial steps undertaken in clinical implementation of personal genome information, and describes the application of whole-genome and exome sequencing to identify the cause of genetic diseases and to suggest adjuvant therapies. Better analysis tools and a deeper understanding of the biology of our genome are necessary in order to decipher, interpret, and optimize clinical utility of what the variation in the human genome can teach us. Personal genome sequencing may eventually become an instrument of common medical practice, providing information that assists in the formulation of a differential diagnosis. We outline herein some of the remaining challenges. PMID:22248320

  5. Parasites, ecosystems and sustainability: an ecological and complex systems perspective.

    Science.gov (United States)

    Horwitz, Pierre; Wilcox, Bruce A

    2005-06-01

    Host-parasite relationships can be conceptualised either narrowly, where the parasite is metabolically dependent on the host, or more broadly, as suggested by an ecological-evolutionary and complex systems perspective. In this view Host-parasite relationships are part of a larger set of ecological and co-evolutionary interdependencies and a complex adaptive system. These interdependencies affect not just the hosts, vectors, parasites, the immediate agents, but also those indirectly or consequentially affected by the relationship. Host-parasite relationships also can be viewed as systems embedded within larger systems represented by ecological communities and ecosystems. So defined, it can be argued that Host-parasite relationships may often benefit their hosts and contribute significantly to the structuring of ecological communities. The broader, complex adaptive system view also contributes to understanding the phenomenon of disease emergence, the ecological and evolutionary mechanisms involved, and the role of parasitology in research and management of ecosystems in light of the apparently growing problem of emerging infectious diseases in wildlife and humans. An expanded set of principles for integrated parasite management is suggested by this perspective.

  6. The human malaria parasite Pfs47 gene mediates evasion of the mosquito immune system

    NARCIS (Netherlands)

    Molina-Cruz, A.; Garver, L.S.; Alabaster, A.; Bangiolo, L.; Haile, A.; Winikor, J.; Ortega, C.; Schaijk, B.C.L. van; Sauerwein, R.W.; Taylor-Salmon, E.; Barillas-Mury, C.

    2013-01-01

    Plasmodium falciparum transmission by Anopheles gambiae mosquitoes is remarkably efficient, resulting in a very high prevalence of human malaria infection in sub-Saharan Africa. A combination of genetic mapping, linkage group selection, and functional genomics was used to identify Pfs47 as a P.

  7. Host-parasite interactions and ecology of the malaria parasite-a bioinformatics approach.

    Science.gov (United States)

    Izak, Dariusz; Klim, Joanna; Kaczanowski, Szymon

    2018-04-25

    Malaria remains one of the highest mortality infectious diseases. Malaria is caused by parasites from the genus Plasmodium. Most deaths are caused by infections involving Plasmodium falciparum, which has a complex life cycle. Malaria parasites are extremely well adapted for interactions with their host and their host's immune system and are able to suppress the human immune system, erase immunological memory and rapidly alter exposed antigens. Owing to this rapid evolution, parasites develop drug resistance and express novel forms of antigenic proteins that are not recognized by the host immune system. There is an emerging need for novel interventions, including novel drugs and vaccines. Designing novel therapies requires knowledge about host-parasite interactions, which is still limited. However, significant progress has recently been achieved in this field through the application of bioinformatics analysis of parasite genome sequences. In this review, we describe the main achievements in 'malarial' bioinformatics and provide examples of successful applications of protein sequence analysis. These examples include the prediction of protein functions based on homology and the prediction of protein surface localization via domain and motif analysis. Additionally, we describe PlasmoDB, a database that stores accumulated experimental data. This tool allows data mining of the stored information and will play an important role in the development of malaria science. Finally, we illustrate the application of bioinformatics in the development of population genetics research on malaria parasites, an approach referred to as reverse ecology.

  8. Detection of human filarial parasite Brugia malayi in dogs by histochemical staining and molecular techniques.

    Science.gov (United States)

    Ambily, V R; Pillai, Usha Narayana; Arun, R; Pramod, S; Jayakumar, K M

    2011-09-27

    Human filariasis caused by Brugia malayi is still a public health problem in many countries of Asia including India, Indonesia, Malaysia and Thailand. The World Health Organization (WHO) has targeted to eliminate filariasis by the year 2020 by Mass annual single dose Diethylcarbamazine Administration (MDA). Results of the MDA programme after the first phase was less satisfactory than expected. Malayan filariasis caused by B. malayi is endemic in the south of Thailand where domestic cat serves as the major reservoir host. There is no report about the occurrence of B. malayi in dogs. The present work was carried out to find out the incidence of microfilariasis in dogs and also to detect the presence of human filarial infection in dogs, if any. One hundred dogs above 6 months of age presented to the veterinary college Hospital, Mannuthy, Kerala, with clinical signs suggestive of microfilariasis - fever, anorexia, conjunctivitis, limb and scrotal oedema - were screened for microfilariae by wet film examination. Positive cases were subjected to Giemsa staining, histochemical staining and molecular techniques. Results of the study showed that 80% of dogs had microfilariasis; out of which 20% had sheathed microfilaria. Giemsa and histochemical staining character, PCR and sequencing confirmed it as B. malayi. High prevalence of B. malayi in dogs in this study emphasized the possible role of dogs in transmission of human filariasis. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Effect of Clinoptilolite and Sepiolite Nanoclays on Human and Parasitic Highly Phagocytic Cells

    Directory of Open Access Journals (Sweden)

    Yanis Toledano-Magaña

    2015-01-01

    Full Text Available Nanoclays have potential applications in biomedicine raising the need to evaluate their toxicity in in vitro models as a first approach to its biocompatibility. In this study, in vitro toxicity of clinoptilolite and sepiolite nanoclays (NC was analyzed in highly phagocytic cultures of amoebas and human and mice macrophages. While amebic viability was significantly affected only by sepiolite NC at concentrations higher than 0.1 mg/mL, the effect on macrophage cultures was dependent on the origin of the cells. Macrophages derived from human peripheral blood monocytes were less affected in viability (25% decrease at 48 h, followed by the RAW 264.7 cell line (40%, and finally, macrophages derived from mice bone marrow monocytes (98%. Moreover, the cell line and mice macrophages die mainly by necrosis, whereas human macrophages exhibit increased apoptosis. Cytokine expression analysis in media of sepiolite NC treated cultures showed a proinflammatory profile (INFγ, IL-1α, IL-8, and IL-6, in contrast with clinoptilolite NC that induced lees cytokines with concomitant production of IL-10. The results show that sepiolite NC is more toxic to amoebas and macrophages than clinoptilolite NC, mostly in a time and dose-dependent manner. However, the effect of sepiolite NC was comparable with talc powder suggesting that both NC have low cytotoxicity in vitro.

  10. Finding aroma clues in the human breath to diagnose diseases

    Science.gov (United States)

    A. Dan Wilson

    2016-01-01

    History of human odor analysis in disease diagnosis The use of the sense of smell as an indicator of human disease probably originated with Hippocrates (circa 400 BC). Early medical practitioners recognized that the presence of human diseases changed the odors released from the body and breath. Physicians once relied heavily on their sense of smell to provide useful...

  11. Mitochondrial Fusion Proteins and Human Diseases

    Directory of Open Access Journals (Sweden)

    Michela Ranieri

    2013-01-01

    Full Text Available Mitochondria are highly dynamic, complex organelles that continuously alter their shape, ranging between two opposite processes, fission and fusion, in response to several stimuli and the metabolic demands of the cell. Alterations in mitochondrial dynamics due to mutations in proteins involved in the fusion-fission machinery represent an important pathogenic mechanism of human diseases. The most relevant proteins involved in the mitochondrial fusion process are three GTPase dynamin-like proteins: mitofusin 1 (MFN1 and 2 (MFN2, located in the outer mitochondrial membrane, and optic atrophy protein 1 (OPA1, in the inner membrane. An expanding number of degenerative disorders are associated with mutations in the genes encoding MFN2 and OPA1, including Charcot-Marie-Tooth disease type 2A and autosomal dominant optic atrophy. While these disorders can still be considered rare, defective mitochondrial dynamics seem to play a significant role in the molecular and cellular pathogenesis of more common neurodegenerative diseases, for example, Alzheimer’s and Parkinson’s diseases. This review provides an overview of the basic molecular mechanisms involved in mitochondrial fusion and focuses on the alteration in mitochondrial DNA amount resulting from impairment of mitochondrial dynamics. We also review the literature describing the main disorders associated with the disruption of mitochondrial fusion.

  12. Human prion diseases in the United States.

    Directory of Open Access Journals (Sweden)

    Robert C Holman

    Full Text Available BACKGROUND: Prion diseases are a family of rare, progressive, neurodegenerative disorders that affect humans and animals. The most common form of human prion disease, Creutzfeldt-Jakob disease (CJD, occurs worldwide. Variant CJD (vCJD, a recently emerged human prion disease, is a zoonotic foodborne disorder that occurs almost exclusively in countries with outbreaks of bovine spongiform encephalopathy. This study describes the occurrence and epidemiology of CJD and vCJD in the United States. METHODOLOGY/PRINCIPAL FINDINGS: Analysis of CJD and vCJD deaths using death certificates of US residents for 1979-2006, and those identified through other surveillance mechanisms during 1996-2008. Since CJD is invariably fatal and illness duration is usually less than one year, the CJD incidence is estimated as the death rate. During 1979 through 2006, an estimated 6,917 deaths with CJD as a cause of death were reported in the United States, an annual average of approximately 247 deaths (range 172-304 deaths. The average annual age-adjusted incidence for CJD was 0.97 per 1,000,000 persons. Most (61.8% of the CJD deaths occurred among persons >or=65 years of age for an average annual incidence of 4.8 per 1,000,000 persons in this population. Most deaths were among whites (94.6%; the age-adjusted incidence for whites was 2.7 times higher than that for blacks (1.04 and 0.40, respectively. Three patients who died since 2004 were reported with vCJD; epidemiologic evidence indicated that their infection was acquired outside of the United States. CONCLUSION/SIGNIFICANCE: Surveillance continues to show an annual CJD incidence rate of about 1 case per 1,000,000 persons and marked differences in CJD rates by age and race in the United States. Ongoing surveillance remains important for monitoring the stability of the CJD incidence rates, and detecting occurrences of vCJD and possibly other novel prion diseases in the United States.

  13. Identification of human intestinal parasites affecting an asymptomatic peri-urban Argentinian population using multi-parallel quantitative real-time polymerase chain reaction.

    Science.gov (United States)

    Cimino, Rubén O; Jeun, Rebecca; Juarez, Marisa; Cajal, Pamela S; Vargas, Paola; Echazú, Adriana; Bryan, Patricia E; Nasser, Julio; Krolewiecki, Alejandro; Mejia, Rojelio

    2015-07-17

    In resource-limited countries, stool microscopy is the diagnostic test of choice for intestinal parasites (soil-transmitted helminths and/or intestinal protozoa). However, sensitivity and specificity is low. Improved diagnosis of intestinal parasites is especially important for accurate measurements of prevalence and intensity of infections in endemic areas. The study was carried out in Orán, Argentina. A total of 99 stool samples from a local surveillance campaign were analyzed by concentration microscopy and McMaster egg counting technique compared to the analysis by multi-parallel quantitative real-time polymerase chain reaction (qPCR). This study compared the performance of qPCR assay and stool microscopy for 8 common intestinal parasites that infect humans including the helminths Ascaris lumbricoides, Ancylostoma duodenale, Necator americanus, Strongyloides stercoralis, Trichuris trichiura, and the protozoa Giardia lamblia, Cryptosporidium parvum/hominis, and Entamoeba histolytica, and investigated the prevalence of polyparasitism in an endemic area. qPCR showed higher detection rates for all parasites as compared to stool microscopy except T. trichiura. Species-specific primers and probes were able to distinguish between A. duodenale (19.1%) and N. americanus (36.4%) infections. There were 48.6% of subjects co-infected with both hookworms, and a significant increase in hookworm DNA for A. duodenale versus N. americanus (119.6 fg/μL: 0.63 fg/μL, P parasites in an endemic area that has improved diagnostic accuracy compared to stool microscopy. This first time use of multi-parallel qPCR in Argentina has demonstrated the high prevalence of intestinal parasites in a peri-urban area. These results will contribute to more accurate epidemiological survey, refined treatment strategies on a public scale, and better health outcomes in endemic settings.

  14. Circulating CD14brightCD16+ 'intermediate' monocytes exhibit enhanced parasite pattern recognition in human helminth infection.

    Directory of Open Access Journals (Sweden)

    Joseph D Turner

    2014-04-01

    Full Text Available Circulating monocyte sub-sets have recently emerged as mediators of divergent immune functions during infectious disease but their role in helminth infection has not been investigated. In this study we evaluated whether 'classical' (CD14brightCD16-, 'intermediate' (CD14brightCD16+, and 'non-classical' (CD14dimCD16+ monocyte sub-sets from peripheral blood mononuclear cells varied in both abundance and ability to bind antigenic material amongst individuals living in a region of Northern Senegal which is co-endemic for Schistosoma mansoni and S. haematobium. Monocyte recognition of excretory/secretory (E/S products released by skin-invasive cercariae, or eggs, of S. mansoni was assessed by flow cytometry and compared between S. mansoni mono-infected, S. mansoni and S. haematobium co-infected, and uninfected participants. Each of the three monocyte sub-sets in the different infection groups bound schistosome E/S material. However, 'intermediate' CD14brightCD16+ monocytes had a significantly enhanced ability to bind cercarial and egg E/S. Moreover, this elevation of ligand binding was particularly evident in co-infected participants. This is the first demonstration of modulated parasite pattern recognition in CD14brightCD16+ intermediate monocytes during helminth infection, which may have functional consequences for the ability of infected individuals to respond immunologically to infection.

  15. Sporozoite Route of Infection Influences In Vitro var Gene Transcription of Plasmodium falciparum Parasites From Controlled Human Infections.

    Science.gov (United States)

    Dimonte, Sandra; Bruske, Ellen I; Hass, Johanna; Supan, Christian; Salazar, Carmen L; Held, Jana; Tschan, Serena; Esen, Meral; Flötenmeyer, Matthias; Koch, Iris; Berger, Jürgen; Bachmann, Anna; Sim, Betty K L; Hoffman, Stephen L; Kremsner, Peter G; Mordmüller, Benjamin; Frank, Matthias

    2016-09-15

    Antigenic variation in Plasmodium falciparum is mediated by the multicopy var gene family. Each parasite possesses about 60 var genes, and switching between active var loci results in antigenic variation. In the current study, the effect of mosquito and host passage on in vitro var gene transcription was investigated. Thirty malaria-naive individuals were inoculated by intradermal or intravenous injection with cryopreserved, isogenic NF54 P. falciparum sporozoites (PfSPZ) generated from 1 premosquito culture. Microscopic parasitemia developed in 22 individuals, and 21 in vitro cultures were established. The var gene transcript levels were determined in early and late postpatient cultures and in the premosquito culture. At the early time point, all cultures preferentially transcribed 8 subtelomeric var genes. Intradermal infections had higher var gene transcript levels than intravenous infections and a significantly longer intrahost replication time (P = .03). At the late time point, 9 subtelomeric and 8 central var genes were transcribed at the same levels in almost all cultures. Premosquito and late postpatient cultures transcribed the same subtelomeric and central var genes, except for var2csa  The duration of intrahost replication influences in vitro var gene transcript patterns. Differences between premosquito and postpatient cultures decrease with prolonged in vitro growth. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  16. Encapsulation of metalloporphyrins improves their capacity to block the viability of the human malaria parasite Plasmodium falciparum.

    Science.gov (United States)

    Alves, Eduardo; Iglesias, Bernardo A; Deda, Daiana K; Budu, Alexandre; Matias, Tiago A; Bueno, Vânia B; Maluf, Fernando V; Guido, Rafael V C; Oliva, Glaucius; Catalani, Luiz H; Araki, Koiti; Garcia, Celia R S

    2015-02-01

    Several synthetic metallated protoporphyrins (M-PPIX) were tested for their ability to block the cell cycle of the lethal human malaria parasite Plasmodium falciparum. After encapsulating the porphyrin derivatives in micro- and nanocapsules of marine atelocollagen, their effects on cultures of red blood cells infected (RBC) with P. falciparum were verified. RBCs infected with synchronized P. falciparum incubated for 48 h showed a toxic effect over a micromolar range. Strikingly, the IC50 of encapsulated metalloporphyrins reached nanomolar concentrations, where Zn-PPIX showed the best antimalarial effect, with an IC50=330 nM. This value is an 80-fold increase in the antimalarial activity compared to the antimalarial effect of non-encapsulated Zn-PPIX. These findings reveal that the incubation of P. falciparum infected-RBCs with 20 μM Zn-PPIX reduced the size of hemozoin crystal by 34%, whereas a 28% reduction was noticed with chloroquine, confirming the importance of heme detoxification pathway in drug therapy. In this study, synthetic metalloporphyrins were tested as therapeutics that target Plasmodium falciparum. The IC50 of encapsulated metalloporphyrins was found to be in the nanomolar concentration range, with encapsulated Zn-PPIX showing an 80-fold increase in its antimalarial activity compared to the non-encapsulated form. Copyright © 2015. Published by Elsevier Inc.

  17. Homology modeling of parasite histone deacetylases to guide the structure-based design of selective inhibitors.

    Science.gov (United States)

    Melesina, Jelena; Robaa, Dina; Pierce, Raymond J; Romier, Christophe; Sippl, Wolfgang

    2015-11-01

    Histone deacetylases (HDACs) are promising epigenetic targets for the treatment of various diseases, including cancer and neurodegenerative disorders. There is evidence that they can also be addressed to treat parasitic infections. Recently, the first X-ray structure of a parasite HDAC was published, Schistosoma mansoni HDAC8, giving structural insights into its inhibition. However, most of the targets from parasites of interest still lack this structural information. Therefore, we prepared homology models of relevant parasitic HDACs and compared them to human and S. mansoni HDACs. The information about known S. mansoni HDAC8 inhibitors and compounds that affect the growth of Trypanosoma, Leishmania and Plasmodium species was used to validate the models by docking and molecular dynamics studies. Our results provide analysis of structural features of parasitic HDACs and should be helpful for selecting promising candidates for biological testing and for structure-based optimisation of parasite-specific inhibitors. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Prevalence of Parasitic Contamination

    Science.gov (United States)

    Ismail, Yazan

    2016-01-01

    One of the main ways in transmitting parasites to humans is through consuming contaminated raw vegetables. The aim of this study was to evaluate the prevalence of parasitological contamination (helminthes eggs, Giardia and Entamoeba histolytica cysts) of salad vegetables sold at supermarkets and street vendors in Amman and Baqa’a – Jordan. A total of 133 samples of salad vegetables were collected and examined for the prevalence of parasites. It was found that 29% of the samples were contaminated with different parasites. Of the 30 lettuce, 33 tomato, 42 parsley and 28 cucumber samples examined the prevalence of Ascaris spp. eggs was 43%, 15%, 21% and 4%; Toxocara spp. eggs was 30%, 0%, 0% and 4%; Giardia spp. cysts was 23%, 6%, 0% and 0%; Taenia/Echinococcus eggs was 20%, 0%, 5% and 0%; Fasciola hepatica eggs was 13%, 3%, 2% and 0%; and E. histolytica cysts was 10%, 6%, 0% and 0%, respectively. There was no significant difference in the prevalence of parasite in salad vegetables either between supermarkets and street vendors, or between Amman and Baqa’a, Ascaris spp. was found to be the highest prevalent parasite in salad vegetables from supermarkets and street vendors and from Amman and Baqa’a. Our results pointed out that, the parasitic contamination of salad vegetables found in our study might be caused by irrigating crops with faecal contaminated water. We concluded that salad vegetables sold in Amman and Baqa’a may cause a health risk to consumers.

  19. A subset of group A-like var genes encodes the malaria parasite ligands for binding to human brain endothelial cells

    DEFF Research Database (Denmark)

    Claessens, Antoine; Adams, Yvonne; Ghumra, Ashfaq

    2012-01-01

    Cerebral malaria is the most deadly manifestation of infection with Plasmodium falciparum. The pathology of cerebral malaria is characterized by the accumulation of infected erythrocytes (IEs) in the microvasculature of the brain caused by parasite adhesins on the surface of IEs binding to human...... receptors on microvascular endothelial cells. The parasite and host molecules involved in this interaction are unknown. We selected three P. falciparum strains (HB3, 3D7, and IT/FCR3) for binding to a human brain endothelial cell line (HBEC-5i). The whole transcriptome of isogenic pairs of selected.......029) but not by antibodies from controls with uncomplicated malaria (Mann-Whitney test, P = 0.58). This work describes a binding phenotype for virulence-associated group A P. falciparum erythrocyte membrane protein 1 variants and identifies targets for interventions to treat or prevent cerebral malaria....

  20. Characterizing Ancylostoma caninum transcriptome and exploring nematode parasitic adaptation

    Directory of Open Access Journals (Sweden)

    Hawdon John

    2010-05-01

    Full Text Available Abstract Background Hookworm infection is one of the most important neglected diseases in developing countries, with approximately 1 billion people infected worldwide. To better understand hookworm biology and nematode parasitism, the present study generated a near complete transcriptome of the canine hookworm Ancylostoma caninum to a very high coverage using high throughput technology, and compared it to those of the free-living nematode Caenorhabditis elegans and the parasite Brugia malayi. Results The generated transcripts from four developmental stages, infective L3, serum stimulated L3, adult male and adult female, covered 93% of the A. caninum transcriptome. The broad diversity among nematode transcriptomes was confirmed, and an impact of parasitic adaptation on transcriptome diversity was inferred. Intra-population analysis showed that A. caninum has higher coding sequence diversity than humans. Examining the developmental expression profiles of A. caninum revealed major transitions in gene expression from larval stages to adult. Adult males expressed the highest number of selectively expressed genes, but adult female expressed the highest number of selective parasitism-related genes. Genes related to parasitism adaptation and A. caninum specific genes exhibited more expression selectivity while those conserved in nematodes tend to be consistently expressed. Parasitism related genes were expressed more selectively in adult male and female worms. The comprehensive analysis of digital expression profiles along with transcriptome comparisons enabled identification of a set of parasitism genes encoding secretory proteins in animal parasitic nematode. Conclusions This study validated the usage of deep sequencing for gene expression profiling. Parasitic adaptation of the canine hookworm is related to its diversity and developmental dynamics. This comprehensive comparative genomic and expression study substantially improves our understanding of

  1. Parasitic contamination of fruits and vegetables in Benin city, Edo ...

    African Journals Online (AJOL)

    Aim: The consumption of fresh fruits and vegetables helps in protecting the human body from diseases and also has a positive impact on body-weight regulation and related conditions, including diabetes and hypertension. This study was conducted to determine the parasitic contamination of fruits and vegetables in Benin ...

  2. [Analysis on Research Projects Supported by the National Natural Science Foundation of China at the National Institute of Parasitic Diseases during 2003-2013].

    Science.gov (United States)

    Zhou, Xiao-jun; Zheng, Bin; Yi, Feng-yun; Xiong, Yan-hong; Zhang, Min-qi

    2015-04-01

    The data of the National Natural Science Foundation (NSFC) projests obtained by the National Institute of Parasitic Diseases (NIPD), Chinese Center for Disease Control and Prevention (China CDC) during 2003-2013 were collected from internet-based science information system of NSFC, and NSFC search tool of Dingxiang Garden (http://nsfc.biomart.cn/). The number of funded projects, their subject classification and approved amount were analyzed, and compared with the other institutes of China CDC. Furthermore, the rationalization proposals were given in order to enhance the level of foundation management in the future.

  3. Issues of the presence of parasitic protozoa in surface waters

    Science.gov (United States)

    Hawrylik, Eliza

    2018-02-01

    Parasitic protozoa are very numerous organisms in the environment that play an important role in the spread of water-borne diseases. Water-borne epidemics caused by parasitic protozoa are noted throughout the world. Within these organisms, intestinal protozoa of the genera Cryptosporidium and Giardia are ones of the most serious health hazards for humans. This paper focuses on the problem of the presence of parasitic protozoa in surface waters. Characteristics of the most frequently recognized pathogens responsible for water-borne outbreaks were described, as well as sources of contamination and surface waters contamination due to protozoa of the genus Cryptosporidium and Giardia were presented. The methods of destroying the cysts and oocysts of parasitic protozoa used nowadays in the world were also presented in a review.

  4. Repetitive elements in parasitic protozoa

    Directory of Open Access Journals (Sweden)

    Clayton Christine

    2010-05-01

    Full Text Available Abstract A recent paper published in BMC Genomics suggests that retrotransposition may be active in the human gut parasite Entamoeba histolytica. This adds to our knowledge of the various types of repetitive elements in parasitic protists and the potential influence of such elements on pathogenicity. See research article http://www.biomedcentral.com/1471-2164/11/321

  5. Optimising Controlled Human Malaria Infection Studies Using Cryopreserved P. falciparum Parasites Administered by Needle and Syringe.

    Directory of Open Access Journals (Sweden)

    Susanne H Sheehy

    Full Text Available Controlled human malaria infection (CHMI studies have become a routine tool to evaluate efficacy of candidate anti-malarial drugs and vaccines. To date, CHMI trials have mostly been conducted using the bite of infected mosquitoes, restricting the number of trial sites that can perform CHMI studies. Aseptic, cryopreserved P. falciparum sporozoites (PfSPZ Challenge provide a potentially more accurate, reproducible and practical alternative, allowing a known number of sporozoites to be administered simply by injection.We sought to assess the infectivity of PfSPZ Challenge administered in different dosing regimens to malaria-naive healthy adults (n = 18. Six participants received 2,500 sporozoites intradermally (ID, six received 2,500 sporozoites intramuscularly (IM and six received 25,000 sporozoites IM.Five out of six participants receiving 2,500 sporozoites ID, 3/6 participants receiving 2,500 sporozoites IM and 6/6 participants receiving 25,000 sporozoites IM were successfully infected. The median time to diagnosis was 13.2, 17.8 and 12.7 days for 2,500 sporozoites ID, 2,500 sporozoites IM and 25,000 sporozoites IM respectively (Kaplan Meier method; p = 0.024 log rank test.2,500 sporozoites ID and 25,000 sporozoites IM have similar infectivities. Given the dose response in infectivity seen with IM administration, further work should evaluate increasing doses of PfSPZ Challenge IM to identify a dosing regimen that reliably infects 100% of participants.ClinicalTrials.gov NCT01465048.

  6. Multiple Zoonotic Parasites Identified in Dog Feces Collected in Ponte de Lima, Portugal — A Potential Threat to Human Health

    Science.gov (United States)

    Letra Mateus, Teresa; Castro, António; Niza Ribeiro, João; Vieira-Pinto, Madalena

    2014-01-01

    Dogs play many roles and their presence within people’s houses has increased. In rural settings dog faeces are not removed from the streets, representing an environmental pollution factor. Our aim was to evaluate the occurrence of environmental contamination with zoonotic intestinal parasites of three groups of dogs in Ponte de Lima, Portugal, with a particular emphasis on Echinococcus granulosus. We collected 592 dog faecal samples from the environment, farm and hunting dogs. Qualitative flotation coprological analysis was performed and the frequency in the positive samples ranged between 57.44% and 81.19% in different groups. We isolated up to four different parasites in one sample and detected seven intestinal parasitic species, genera or families overall. Ancylostomatidae was the most prevalent parasite, followed by Trichuris spp., Toxocara spp., Isospora spp., Dipylidium caninum, Taeniidae and Toxascaris leonina. Taeniidae eggs were analyzed with the PCR technique and revealed not to be from Echinococcus. The parasite prevalence and the diversity of zoonotic parasites found were high, which calls for a greater awareness of the problem among the population, especially hunters. Promoting research at the local level is important to plan control strategies. Health education should be developed with regard to farmers and hunters, and a closer collaboration between researchers, practitioners and public health authorities is needed. PMID:25257358

  7. Multiple Zoonotic Parasites Identified in Dog Feces Collected in Ponte de Lima, Portugal—A Potential Threat to Human Health

    Directory of Open Access Journals (Sweden)

    Teresa Letra Mateus

    2014-09-01

    Full Text Available Dogs play many roles and their presence within people’s houses has increased. In rural settings dog faeces are not removed from the streets, representing an environmental pollution factor. Our aim was to evaluate the occurrence of environmental contamination with zoonotic intestinal parasites of three groups of dogs in Ponte de Lima, Portugal, with a particular emphasis on Echinococcus granulosus. We collected 592 dog faecal samples from the environment, farm and hunting dogs. Qualitative flotation coprological analysis was performed and the frequency in the positive samples ranged between 57.44% and 81.19% in different groups. We isolated up to four different parasites in one sample and detected seven intestinal parasitic species, genera or families overall. Ancylostomatidae was the most prevalent parasite, followed by Trichuris spp., Toxocara spp., Isospora spp., Dipylidium caninum, Taeniidae and Toxascaris leonina. Taeniidae eggs were analyzed with the PCR technique and revealed not to be from Echinococcus. The parasite prevalence and the diversity of zoonotic parasites found were high, which calls for a greater awareness of the problem among the population, especially hunters. Promoting research at the local level is important to plan control strategies. Health education should be developed with regard to farmers and hunters, and a closer collaboration between researchers, practitioners and public health authorities is needed.

  8. A review of wildlife tourism and meta-analysis of parasitism in Africa's national parks and game reserves.

    Science.gov (United States)

    Odeniran, Paul Olalekan; Ademola, Isaiah Oluwafemi; Jegede, Henry Olanrewaju

    2018-06-14

    The recent increase of parasitic diseases associated with wildlife tourism can be traced to human contact with wildlife and intense modification of wildlife habitat. The continental estimates of parasitic diseases among visited wildlife-tourists and mammalian wildlife present in conservation areas are lacking; therefore, a general review was necessary to provide insights into Africa's parasitic disease burden and transmission between humans and wildlife. A two-step analysis was conducted with searches in Ovid MEDLINE, EMBASE, PubMed, Web of Science and Global Health. All diseases reported without prevalence were grouped and analysed as categorical data while meta-analysis of prevalence rates of parasitic diseases in wildlife from national parks and reserves in Africa was conducted. Only 4.7% of the tourist centres reported routine wildlife diagnosis for parasitic diseases. Disease intensity shows that cryptosporidiosis and seven other parasitic diseases were observed in both human and wildlife; however, no significant difference in intensity between human and wildlife hosts was observed. Schistosomiasis intensity reports showed a significant increase (P tourism. Pre- and post-travel clinical examinations are important for tourists while routine examination, treatment and rational surveillance are important for these animals to improve wildlife tourism.

  9. PARASITIC CONTAMINATION OF WELLS DRINKING WATER IN MAZANDARAN PROVINCE

    Directory of Open Access Journals (Sweden)

    Z. Yousefi ، H. Ziaei hezarjaribi ، A. A. Enayati ، R. A. Mohammadpoor

    2009-10-01

    Full Text Available There is a direct relation between the prevalence of some parasitic diseases and the presence of those etiologic agents in water. The purpose of this research was to determine the contamination rate of wells drinking water to parasites in Mazandaran province in the north of Iran. 989 water samples were randomly taken based on the population of towns and number of health centers from 12 cities of Mazandaran province and transferred to the laboratory in sterile containers. Water samples were then filtered and analyzed according to the World Health Organization guidelines. Direct method and Gram staining procedure were used to identify the parasites. If cryptosporidium was seen, floatation (sheather’s sugar and modified Ziehl-Neelsen staining method were performed. Parasites count was undertaken using McMaster counting slide (0.3 mL. 197 out of 989 water samples were contaminated with different parasites. From 197 contaminated samples, 20 different types of parasites were separated of which 53 (26.9% were pathogenic, 100 (50.8% non pathogenic, and 44 non-infective stages of parasites. Distance between wells and sources of contamination, type of water distribution systems, city and chlorination status had significantly statistical relationship with contamination prevalence (p<0.001. According to the results and considering the direct correlation between safe water and human health, proper implementation of providing hygienic drinking water should be enforced.

  10. Leishmania development in sand flies: parasite-vector interactions overview.

    Science.gov (United States)

    Dostálová, Anna; Volf, Petr

    2012-12-03

    Leishmaniases are vector-borne parasitic diseases with 0.9 - 1.4 million new human cases each year worldwide. In the vectorial part of the life-cycle, Leishmania development is confined to the digestive tract. During the first few days after blood feeding, natural barriers to Leishmania development include secreted proteolytic enzymes, the peritrophic matrix surrounding the ingested blood meal and sand fly immune reactions. As the blood digestion proceeds, parasites need to bind to the midgut epithelium to avoid being excreted with the blood remnant. This binding is strictly stage-dependent as it is a property of nectomonad and leptomonad forms only. While the attachment in specific vectors (P. papatasi, P. duboscqi and P. sergenti) involves lipophosphoglycan (LPG), this Leishmania molecule is not required for parasite attachment in other sand fly species experimentally permissive for various Leishmania. During late-stage infections, large numbers of parasites accumulate in the anterior midgut and produce filamentous proteophosphoglycan creating a gel-like plug physically obstructing the gut. The parasites attached to the stomodeal valve cause damage to the chitin lining and epithelial cells of the valve, interfering with its function and facilitating reflux of parasites from the midgut. Transformation to metacyclic stages highly infective for the vertebrate host is the other prerequisite for effective transmission. Here, we review the current state of knowledge of molecular interactions occurring in all these distinct phases of parasite colonization of the sand fly gut, highlighting recent discoveries in the field.

  11. Fishing drives declines in fish parasite diversity and has variable effects on parasite abundance.

    Science.gov (United States)

    Wood, Chelsea L; Sandin, Stuart A; Zgliczynski, Brian; Guerra, Ana Sofía; Micheli, Fiorenza

    2014-07-01

    Despite the ubiquity and ecological importance of parasites, relatively few studies have assessed their response to anthropogenic environmental change. Heuristic models have predicted both increases and decreases in parasite abundance in response to human disturbance, with empirical support for both. However, most studies focus on one or a few selected parasite species. Here, we assess the abundance of parasites of seven species of coral reef fishes collected from three fished and three unfished islands of the Line Islands archipelago in the central equatorial Pacific. Because we chose fish hosts that spanned different trophic levels, taxonomic groups, and body sizes, we were able to compare parasite responses across a broad cross section of the total parasite community in the presence and absence of fishing, a major human impact on marine ecosystems. We found that overall parasite species richness was substantially depressed on fished islands, but that the response of parasite abundance varied among parasite taxa: directly transmitted parasites were significantly more abundant on fished than on unfished islands, while the reverse was true for trophically transmitted parasites. This probably arises because trophically transmitted parasites require multiple host species, some of which are the top predators most sensitive to fishing impacts. The increase in directly transmitted parasites appeared to be due to fishing-driven compensatory increases in the abundance of their hosts. Together, these results provide support for the predictions of both heuristic models, and indicate that the direction of fishing's impact on parasite abundance is mediated by parasite traits, notably parasite transmission strategies.

  12. Parasites and malignancies, a review, with emphasis on digestive cancer induced by Cryptosporidium parvum (Alveolata: Apicomplexa).

    Science.gov (United States)

    Benamrouz, S; Conseil, V; Creusy, C; Calderon, E; Dei-Cas, E; Certad, G

    2012-05-01

    The International Agency for Research on Cancer (IARC) identifies ten infectious agents (viruses, bacteria, parasites) able to induce cancer disease in humans. Among parasites, a carcinogenic role is currently recognized to the digenetic trematodes Schistosoma haematobium, leading to bladder cancer, and to Clonorchis sinensis or Opisthorchis viverrini, which cause cholangiocarcinoma. Furthermore, several reports suspected the potential association of other parasitic infections (due to Protozoan or Metazoan parasites) with the development of neoplastic changes in the host tissues. The present work shortly reviewed available data on the involvement of parasites in neoplastic processes in humans or animals, and especially focused on the carcinogenic power of Cryptosporidium parvum infection. On the whole, infection seems to play a crucial role in the etiology of cancer.

  13. Parasites and malignancies, a review, with emphasis on digestive cancer induced by Cryptosporidium parvum (Alveolata: Apicomplexa

    Directory of Open Access Journals (Sweden)

    Benamrouz S.

    2012-05-01

    Full Text Available The International Agency for Research on Cancer (IARC identifies ten infectious agents (viruses, bacteria, parasites able to induce cancer disease in humans. Among parasites, a carcinogenic role is currently recognized to the digenetic trematodes Schistosoma haematobium, leading to bladder cancer, and to Clonorchis sinensis or Opisthorchis viverrini, which cause cholangiocarcinoma. Furthermore, several reports suspected the potential association of other parasitic infections (due to Protozoan or Metazoan parasites with the development of neoplastic changes in the host tissues. The present work shortly reviewed available data on the involvement of parasites in neoplastic processes in humans or animals, and especially focused on the carcinogenic power of Cryptosporidium parvum infection. On the whole, infection seems to play a crucial role in the etiology of cancer.

  14. Similarities and differences between helminth parasites and cancer cell lines in shaping human monocytes: Insights into parallel mechanisms of immune evasion.

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    Prakash Babu Narasimhan

    2018-04-01

    Full Text Available A number of features at the host-parasite interface are reminiscent of those that are also observed at the host-tumor interface. Both cancer cells and parasites establish a tissue microenvironment that allows for immune evasion and may reflect functional alterations of various innate cells. Here, we investigated how the phenotype and function of human monocytes is altered by exposure to cancer cell lines and if these functional and phenotypic alterations parallel those induced by exposure to helminth parasites. Thus, human monocytes were exposed to three different cancer cell lines (breast, ovarian, or glioblastoma or to live microfilariae (mf of Brugia malayi-a causative agent of lymphatic filariasis. After 2 days of co-culture, monocytes exposed to cancer cell lines showed markedly upregulated expression of M1-associated (TNF-α, IL-1β, M2-associated (CCL13, CD206, Mreg-associated (IL-10, TGF-β, and angiogenesis associated (MMP9, VEGF genes. Similar to cancer cell lines, but less dramatically, mf altered the mRNA expression of IL-1β, CCL13, TGM2 and MMP9. When surface expression of the inhibitory ligands PDL1 and PDL2 was assessed, monocytes exposed to both cancer cell lines and to live mf significantly upregulated PDL1 and PDL2 expression. In contrast to exposure to mf, exposure to cancer cell lines increased the phagocytic ability of monocytes and reduced their ability to induce T cell proliferation and to expand Granzyme A+ CD8+ T cells. Our data suggest that despite the fact that helminth parasites and cancer cell lines are extraordinarily disparate, they share the ability to alter the phenotype of human monocytes.

  15. Similarities and differences between helminth parasites and cancer cell lines in shaping human monocytes: Insights into parallel mechanisms of immune evasion.

    Science.gov (United States)

    Narasimhan, Prakash Babu; Akabas, Leor; Tariq, Sameha; Huda, Naureen; Bennuru, Sasisekhar; Sabzevari, Helen; Hofmeister, Robert; Nutman, Thomas B; Tolouei Semnani, Roshanak

    2018-04-01

    A number of features at the host-parasite interface are reminiscent of those that are also observed at the host-tumor interface. Both cancer cells and parasites establish a tissue microenvironment that allows for immune evasion and may reflect functional alterations of various innate cells. Here, we investigated how the phenotype and function of human monocytes is altered by exposure to cancer cell lines and if these functional and phenotypic alterations parallel those induced by exposure to helminth parasites. Thus, human monocytes were exposed to three different cancer cell lines (breast, ovarian, or glioblastoma) or to live microfilariae (mf) of Brugia malayi-a causative agent of lymphatic filariasis. After 2 days of co-culture, monocytes exposed to cancer cell lines showed markedly upregulated expression of M1-associated (TNF-α, IL-1β), M2-associated (CCL13, CD206), Mreg-associated (IL-10, TGF-β), and angiogenesis associated (MMP9, VEGF) genes. Similar to cancer cell lines, but less dramatically, mf altered the mRNA expression of IL-1β, CCL13, TGM2 and MMP9. When surface expression of the inhibitory ligands PDL1 and PDL2 was assessed, monocytes exposed to both cancer cell lines and to live mf significantly upregulated PDL1 and PDL2 expression. In contrast to exposure to mf, exposure to cancer cell lines increased the phagocytic ability of monocytes and reduced their ability to induce T cell proliferation and to expand Granzyme A+ CD8+ T cells. Our data suggest that despite the fact that helminth parasites and cancer cell lines are extraordinarily disparate, they share the ability to alter the phenotype of human monocytes.

  16. Role of Carbamylated Biomolecules in Human Diseases.

    Science.gov (United States)

    Badar, Asim; Arif, Zarina; Alam, Khursheed

    2018-04-01

    Carbamylation (or carbamoylation) is a non-enzymatic modification of biomolecules mediated by cyanate, a dissociation product of urea. Proteins are more sensitive to carbamylation. Two major sites of carbamylation reaction are: N α -amino moiety of a protein N-terminus and the N ɛ -amino moiety of proteins' lysine residues. In kidney diseases, urea accumulates and the burden of carbamylation increases. This may lead to alteration in the structure and function of many important proteins relevant in maintenance of homeostasis. Carbamylated proteins namely, carbamylated-haemoglobin and carbamylated-low density lipoprotein (LDL) have been implicated in hypoxia and atherosclerosis, respectively. Furthermore, carbamylation of insulin, oxytocin, and erythropoietin have caused changes in the action of these hormones vis-à-vis the metabolic pathways they control. In this short review, authors have compiled the data on role of carbamylated proteins, enzymes, hormones, LDL, and so on, in human diseases. © 2018 IUBMB Life, 70(4):267-275, 2018. © 2018 International Union of Biochemistry and Molecular Biology.

  17. The most important parasites in Serbia involving the foodborne route of transmission

    Science.gov (United States)

    Petrović, J. M.; Prodanov-Radulović, J. Z.; Vasilev, S. D.

    2017-09-01

    Food can be an important route for transmission of parasites to humans. Compared to other foodborne pathogens in Serbia, foodborne (or potentially foodborne) parasites do not get the attention they undoubtedly deserve. The aim of this article is to give an overview of the most important parasitic pathogens that can be transmitted by food, and that cause disease in humans: Echinococcus, Trichinella, Taenia solium and Toxoplasma gondii. For each of these pathogens, the severity of human diseases they cause, incidence, mortality and case fatality rate among humans in Serbia as well as their prevalence in animal species in Serbia are described. Some of the described foodborne parasites can induce severe disease symptoms in humans associated with high case fatality rates, while others can cause massive outbreaks. All of the aforementioned parasites occur throughout Serbia and cause both severe public health problems and substantial economic losses in livestock production. In conclusion, the control measures of foodborne parasites certainly need to include education of farmers and improvement of veterinary sanitary measures in animal farming and animal waste control.

  18. Medicinal Plants: A Source of Anti-Parasitic Secondary Metabolites

    Directory of Open Access Journals (Sweden)

    Michael Wink

    2012-10-01

    Full Text Available This review summarizes human infections caused by endoparasites, including protozoa, nematodes, trematodes, and cestodes, which affect more than 30% of the human population, and medicinal plants of potential use in their treatment. Because vaccinations do not work in most instances and the parasites have sometimes become resistant to the available synthetic therapeutics, it is important to search for alternative sources of anti-parasitic drugs. Plants produce a high diversity of secondary metabolites with interesting biological activities, such as cytotoxic, anti-parasitic and anti-microbial properties. These drugs often interfere with central targets in parasites, such as DNA (intercalation, alkylation, membrane integrity, microtubules and neuronal signal transduction. Plant extracts and isolated secondary metabolites which can inhibit protozoan parasites, such as Plasmodium, Trypanosoma, Leishmania, Trichomonas and intestinal worms are discussed. The identified plants and compounds offer a chance to develop new drugs against parasitic diseases. Most of them need to be tested in more detail, especially in animal models and if successful, in clinical trials.

  19. Helminth Parasites and the Modulation of Joint Inflammation

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    Chelsea E. Matisz

    2011-01-01

    Full Text Available There is an urgent need to develop better therapeutics for autoimmune and autoinflammatory diseases, of which musculoskeletal disorders such as rheumatoid arthritis are particularly prevalent and debilitating. Helminth parasites are accomplished masters at modifying their hosts' immune activity, and so attention has focused on rodent-helminth model systems to uncover the workings of the mammalian immune response to metazoan parasites, with the hope of revealing molecules and/or mechanisms that can be translated into better treatments for human autoimmune and idiopathic disorders. Substantial proof-of-principal data supporting the concept that infection with helminth parasites can reduce the severity of concomitant disease has been amassed from models of mucosal inflammation. Indeed, infection with helminth parasites has been tried as a therapy in inflammatory bowel disease, and there are case reports relating to other conditions (e.g., autism; however, the impact of infection with parasitic helminths on musculoskeletal diseases has not been extensively studied. Here, we present the view that such a strategy should be applied to the amelioration of joint inflammation and review the literature that supports this contention.

  20. Linking environmental nutrient enrichment and disease emergence in humans and wildlife

    Science.gov (United States)

    Johnson, Pieter T. J.; Townsend, Alan R.; Cleveland, Cory C.; Glibert, Patricia M.; Howarth, Robert W.; McKenzie, Valerie J.; Rejmankova, Eliska; Ward, Mary H.

    2009-01-01

    Worldwide increases in the numbers of human and wildlife diseases present ecologists with the challenge of understanding how large-scale environmental changes affect host-parasite interactions. One of the most profound changes to Earth’s ecosystems is the alteration of global nutrient cycles, including those of phosphorus (P) and especially nitrogen (N). Alongside the obvious direct benefits of nutrient application for food production, growing evidence suggests that anthropogenic inputs of N and P can indirectly affect the abundance of infectious and noninfectious pathogens, sometimes leading to epidemic conditions. However, the mechanisms underpinning observed correlations, and how such patterns vary with disease type, have long remained conjectural. Here, we discuss recent experimental advances in this area to critically evaluate the relationship between environmental nutrient enrichment and disease. Given the inter-related nature of human and wildlife disease emergence, we include a broad range of human and wildlife examples from terrestrial, marine and freshwater ecosystems. We examine the consequences of nutrient pollution on directly transmitted, vector-borne, complex life cycle, and noninfectious pathogens, including West Nile virus, malaria, harmful algal blooms, coral reef diseases and amphibian malformations. Our synthetic examination suggests that the effects of environmental nutrient enrichment on disease are complex and multifaceted, varying with the type of pathogen, host species and condition, attributes of the ecosystem and the degree of enrichment; some pathogens increase in abundance whereas others decline or disappear. Nevertheless, available evidence indicates that ecological changes associated with nutrient enrichment often exacerbate infection and disease caused by generalist parasites with direct or simple life cycles. Observed mechanisms include changes in host/vector density, host distribution, infection resistance, pathogen virulence or

  1. Melatonin-Induced Temporal Up-Regulation of Gene Expression Related to Ubiquitin/Proteasome System (UPS in the Human Malaria Parasite Plasmodium falciparum

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    Fernanda C. Koyama

    2014-12-01

    Full Text Available There is an increasing understanding that melatonin and the ubiquitin/ proteasome system (UPS interact to regulate multiple cellular functions. Post-translational modifications such as ubiquitination are important modulators of signaling processes, cell cycle and many other cellular functions. Previously, we reported a melatonin-induced upregulation of gene expression related to ubiquitin/proteasome system (UPS in Plasmodium falciparum, the human malaria parasite, and that P. falciparum protein kinase 7 influences this process. This implies a role of melatonin, an indolamine, in modulating intraerythrocytic development of the parasite. In this report we demonstrate by qPCR analysis, that melatonin induces gene upregulation in nine out of fourteen genes of the UPS, consisting of the same set of genes previously reported, between 4 to 5 h after melatonin treatment. We demonstrate that melatonin causes a temporally controlled gene expression of UPS members.

  2. The impact of Fusarium mycotoxins on human and animal host susceptibility to infectious diseases.

    Science.gov (United States)

    Antonissen, Gunther; Martel, An; Pasmans, Frank; Ducatelle, Richard; Verbrugghe, Elin; Vandenbroucke, Virginie; Li, Shaoji; Haesebrouck, Freddy; Van Immerseel, Filip; Croubels, Siska

    2014-01-28

    Contamination of food and feed with mycotoxins is a worldwide problem. At present, acute mycotoxicosis caused by high doses is rare in humans and animals. Ingestion of low to moderate amounts of Fusarium mycotoxins is common and generally does not result in obvious intoxication. However, these low amounts may impair intestinal health, immune function and/or pathogen fitness, resulting in altered host pathogen interactions and thus a different outcome of infection. This review summarizes the current state of knowledge about the impact of Fusarium mycotoxin exposure on human and animal host susceptibility to infectious diseases. On the one hand, exposure to deoxynivalenol and other Fusarium mycotoxins generally exacerbates infections with parasites, bacteria and viruses across a wide range of animal host species. Well-known examples include coccidiosis in poultry, salmonellosis in pigs and mice, colibacillosis in pigs, necrotic enteritis in poultry, enteric septicemia of catfish, swine respiratory disease, aspergillosis in poultry and rabbits, reovirus infection in mice and Porcine Reproductive and Respiratory Syndrome Virus infection in pigs. However, on the other hand, T-2 toxin has been shown to markedly decrease the colonization capacity of Salmonella in the pig intestine. Although the impact of the exposure of humans to Fusarium toxins on infectious diseases is less well known, extrapolation from animal models suggests possible exacerbation of, for instance, colibacillosis and salmonellosis in humans, as well.

  3. Internal parasites of reptiles.

    Science.gov (United States)

    Raś-Noryńska, Małgorzata; Sokół, Rajmund

    2015-01-01

    Nowadays a growing number of exotic reptiles are kept as pets. The aim of this study was to determine the species of parasites found in reptile patients of veterinary practices in Poland. Fecal samples obtained from 76 lizards, 15 turtles and 10 snakes were examined by flotation method and direct smear stained with Lugol's iodine. In 63 samples (62.4%) the presence of parasite eggs and oocysts was revealed. Oocysts of Isospora spp. (from 33% to 100% of the samples, depending on the reptilian species) and Oxyurids eggs (10% to 75%) were predominant. In addition, isolated Eimeria spp. oocysts and Giardia intestinalis cysts were found, as well as Strongylus spp. and Hymenolepis spp. eggs. Pet reptiles are often infected with parasites, some of which are potentially dangerous to humans. A routine parasitological examination should be done in such animals.

  4. High-throughput genotyping assay for the large-scale genetic characterization of Cryptosporidium parasites from human and bovine samples.

    Science.gov (United States)

    Abal-Fabeiro, J L; Maside, X; Llovo, J; Bello, X; Torres, M; Treviño, M; Moldes, L; Muñoz, A; Carracedo, A; Bartolomé, C

    2014-04-01

    The epidemiological study of human cryptosporidiosis requires the characterization of species and subtypes involved in human disease in large sample collections. Molecular genotyping is costly and time-consuming, making the implementation of low-cost, highly efficient technologies increasingly necessary. Here, we designed a protocol based on MALDI-TOF mass spectrometry for the high-throughput genotyping of a panel of 55 single nucleotide variants (SNVs) selected as markers for the identification of common gp60 subtypes of four Cryptosporidium species that infect humans. The method was applied to a panel of 608 human and 63 bovine isolates and the results were compared with control samples typed by Sanger sequencing. The method allowed the identification of species in 610 specimens (90·9%) and gp60 subtype in 605 (90·2%). It displayed excellent performance, with sensitivity and specificity values of 87·3 and 98·0%, respectively. Up to nine genotypes from four different Cryptosporidium species (C. hominis, C. parvum, C. meleagridis and C. felis) were detected in humans; the most common ones were C. hominis subtype Ib, and C. parvum IIa (61·3 and 28·3%, respectively). 96·5% of the bovine samples were typed as IIa. The method performs as well as the widely used Sanger sequencing and is more cost-effective and less time consuming.

  5. Prevalence of gastrointestinal parasites in captive non-human primates of twenty-four zoological gardens in China.

    Science.gov (United States)

    Li, Mei; Zhao, Bo; Li, Bo; Wang, Qiang; Niu, Lili; Deng, Jiabo; Gu, Xiaobin; Peng, Xuerong; Wang, Tao; Yang, Guangyou

    2015-06-01

    Captive primates are susceptible to gastrointestinal (GIT) parasitic infections, which are often zoonotic and can contribute to morbidity and mortality. Fecal samples were examined by the means of direct smear, fecal flotation, fecal sedimentation, and fecal cultures. Of 26.51% (317/1196) of the captive primates were diagnosed gastrointestinal parasitic infections. Trichuris spp. were the most predominant in the primates, while Entamoeba spp. were the most prevalent in Old World monkeys (P primates and the safety of animal keepers and visitors. © 2015 The Authors. Journal of Medical Primatology Published by John Wiley & Sons Ltd.

  6. Interleukin-27 Early Impacts Leishmania infantum Infection in Mice and Correlates with Active Visceral Disease in Humans

    Directory of Open Access Journals (Sweden)

    Begoña Pérez-Cabezas

    2016-11-01

    Full Text Available The complexity of Leishmania-host interactions, one of the main leishmaniasis issues, is yet to be fully understood. We detected elevated IL-27 plasma levels in European patients with active visceral disease caused by Leishmania infantum, which returned to basal levels after successful treatment, suggesting this cytokine as a probable infection mediator. We further addressed this hypothesis recurring to two classical susceptible visceral leishmaniasis mouse models. BALB/c, but not C57BL/6 mice, showed increased IL-27 systemic levels after infection, which was associated with an upregulation of IL-27p28 expression by dendritic cells and higher parasite burdens. Neutralization of IL-27 in acutely infected BALB/c led to decreased parasite burdens and a transient increase in IFN-γ+ splenic T cells, while administration of IL-27 to C57BL/6 promoted a local anti-inflammatory cytokine response at the site of infection and increased parasite loads. Overall we show that, as in humans, BALB/c IL-27 systemic levels are infection-dependently upregulated and may favor parasite installation by controlling inflammation.

  7. Analogs of human genetic skin disease in domesticated animals

    Directory of Open Access Journals (Sweden)

    Justin Finch, MD

    2017-09-01

    The genetic skin diseases we will review are pigmentary mosaicism, piebaldism, albinism, Griscelli syndrome, ectodermal dysplasias, Waardenburg syndrome, and mucinosis in both humans and domesticated animals.

  8. "Koko et les lunettes magiques": An educational entertainment tool to prevent parasitic worms and diarrheal diseases in Côte d'Ivoire.

    Directory of Open Access Journals (Sweden)

    Clémence Essé

    2017-09-01

    Full Text Available Integrated control programs, emphasizing preventive chemotherapy along with health education, can reduce the incidence of soil-transmitted helminthiasis and schistosomiasis. The aim of this study was to develop an educational animated cartoon to improve school children's awareness regarding soil-transmitted helminthiasis, diarrheal diseases, and related hygiene practices in Côte d'Ivoire. The key messages included in the cartoon were identified through prior formative research to specifically address local knowledge gaps.In a first step, preliminary research was conducted to assess the knowledge, attitudes, practices, and beliefs of school-aged children regarding parasitic worm infections and hygiene, to identify key health messages to be included in an animated cartoon. Second, an animated cartoon was produced, which included the drafting of the script and story board, and the production of the cartoon's initial version. Finally, the animated cartoon was pilot tested in eight selected schools and further fine-tuned.According to the questionnaire results, children believed that the consumption of sweet food, eating without washing their hands, sitting on the floor, and eating spoiled food were the main causes of parasitic worm infections. Abdominal pain, diarrhea, lack of appetite, failure to grow, and general fatigue were mentioned as symptoms of parasitic worm infections. Most of the children knew that they should go to the hospital for treatment if they experienced symptoms of parasitic worm diseases. The animated cartoon titled "Koko et les lunettes magiques" was produced by Afrika Toon, in collaboration with a scientific team composed of epidemiologists, civil engineers, and social scientists, and the local school children and teachers. Pilot testing of the animated cartoon revealed that, in the short term, children grasped and kept key messages. Most of the children who were shown the cartoon reported to like it. Acceptance of the

  9. "Koko et les lunettes magiques": An educational entertainment tool to prevent parasitic worms and diarrheal diseases in Côte d'Ivoire.

    Science.gov (United States)

    Essé, Clémence; Koffi, Véronique A; Kouamé, Abel; Dongo, Kouassi; Yapi, Richard B; Moro, Honorine M; Kouakou, Christiane A; Palmeirim, Marta S; Bonfoh, Bassirou; N'Goran, Eliézer K; Utzinger, Jürg; Raso, Giovanna

    2017-09-01

    Integrated control programs, emphasizing preventive chemotherapy along with health education, can reduce the incidence of soil-transmitted helminthiasis and schistosomiasis. The aim of this study was to develop an educational animated cartoon to improve school children's awareness regarding soil-transmitted helminthiasis, diarrheal diseases, and related hygiene practices in Côte d'Ivoire. The key messages included in the cartoon were identified through prior formative research to specifically address local knowledge gaps. In a first step, preliminary research was conducted to assess the knowledge, attitudes, practices, and beliefs of school-aged children regarding parasitic worm infections and hygiene, to identify key health messages to be included in an animated cartoon. Second, an animated cartoon was produced, which included the drafting of the script and story board, and the production of the cartoon's initial version. Finally, the animated cartoon was pilot tested in eight selected schools and further fine-tuned. According to the questionnaire results, children believed that the consumption of sweet food, eating without washing their hands, sitting on the floor, and eating spoiled food were the main causes of parasitic worm infections. Abdominal pain, diarrhea, lack of appetite, failure to grow, and general fatigue were mentioned as symptoms of parasitic worm infections. Most of the children knew that they should go to the hospital for treatment if they experienced symptoms of parasitic worm diseases. The animated cartoon titled "Koko et les lunettes magiques" was produced by Afrika Toon, in collaboration with a scientific team composed of epidemiologists, civil engineers, and social scientists, and the local school children and teachers. Pilot testing of the animated cartoon revealed that, in the short term, children grasped and kept key messages. Most of the children who were shown the cartoon reported to like it. Acceptance of the animated cartoon was high

  10. “Koko et les lunettes magiques”: An educational entertainment tool to prevent parasitic worms and diarrheal diseases in Côte d’Ivoire

    Science.gov (United States)

    Kouamé, Abel; Dongo, Kouassi; Yapi, Richard B.; Moro, Honorine M.; Kouakou, Christiane A.; Palmeirim, Marta S.; Bonfoh, Bassirou; N’Goran, Eliézer K.; Utzinger, Jürg

    2017-01-01

    Background Integrated control programs, emphasizing preventive chemotherapy along with health education, can reduce the incidence of soil-transmitted helminthiasis and schistosomiasis. The aim of this study was to develop an educational animated cartoon to improve school children’s awareness regarding soil-transmitted helminthiasis, diarrheal diseases, and related hygiene practices in Côte d’Ivoire. The key messages included in the cartoon were identified through prior formative research to specifically address local knowledge gaps. Methodology In a first step, preliminary research was conducted to assess the knowledge, attitudes, practices, and beliefs of school-aged children regarding parasitic worm infections and hygiene, to identify key health messages to be included in an animated cartoon. Second, an animated cartoon was produced, which included the drafting of the script and story board, and the production of the cartoon’s initial version. Finally, the animated cartoon was pilot tested in eight selected schools and further fine-tuned. Principal findings According to the questionnaire results, children believed that the consumption of sweet food, eating without washing their hands, sitting on the floor, and eating spoiled food were the main causes of parasitic worm infections. Abdominal pain, diarrhea, lack of appetite, failure to grow, and general fatigue were mentioned as symptoms of parasitic worm infections. Most of the children knew that they should go to the hospital for treatment if they experienced symptoms of parasitic worm diseases. The animated cartoon titled “Koko et les lunettes magiques” was produced by Afrika Toon, in collaboration with a scientific team composed of epidemiologists, civil engineers, and social scientists, and the local school children and teachers. Pilot testing of the animated cartoon revealed that, in the short term, children grasped and kept key messages. Most of the children who were shown the cartoon reported to

  11. Parasitic Apologies

    Science.gov (United States)

    Galatolo, Renata; Ursi, Biagio; Bongelli, Ramona

    2016-01-01

    The action of apologizing can be accomplished as the main business of the interaction or incidentally while participants are doing something else. We refer to these apologies as "parasitic apologies," because they are produced "en passant" (Schegloff, 2007), and focus our analysis on this type of apology occurring at the…

  12. Crystallization and preliminary X-ray analysis of Na-ASP-1, a multi-domain pathogenesis-related-1 protein from the human hookworm parasite Necator americanus

    International Nuclear Information System (INIS)

    Asojo, Oluwatoyin A.; Loukas, Alex; Inan, Mehmet; Barent, Rick; Huang, Jicai; Plantz, Brad; Swanson, Amber; Gouthro, Mark; Meagher, Michael M.; Hotez, Peter J.

    2005-01-01

    In order to clarify the structural basis of the pathogenesis-related-1 domain, Na-ASP-1, the first multi-domain ASP from the human hookworm parasite N. americanus, has been crystallized. 2.2 Å resolution data have been collected from a crystal belonging to the monoclinic space group P2 1 . Human hookworm infection is a major cause of anemia and malnutrition in the developing world. In an effort to control hookworm infection, the Human Hookworm Vaccine Initiative has identified candidate vaccine antigens from the infective larval stage (L3) of the parasite, including a family of pathogenesis-related-1 (PR-1) proteins known as the ancylostoma-secreted proteins (ASPs). The functions of the ASPs are unknown. In addition, it is unclear why some ASPs have one while others have multiple PR-1 domains. There are no known structures of a multi-domain ASP and in an effort to remedy this situation, recombinant Na-ASP-1 has been expressed, purified and crystallized. Na-ASP-1 is a 406-amino-acid multi-domain ASP from the prevalent human hookworm parasite Necator americanus. Useful X-ray data to 2.2 Å have been collected from a crystal that belongs to the monoclinic space group P2 1 with unit-cell parameters a = 67.7, b = 74.27, c = 84.60 Å, β = 112.12°. An initial molecular-replacement solution has been obtained with one monomer in the asymmetric unit

  13. Crystallization and preliminary X-ray analysis of Na-ASP-1, a multi-domain pathogenesis-related-1 protein from the human hookworm parasite Necator americanus

    Energy Technology Data Exchange (ETDEWEB)

    Asojo, Oluwatoyin A., E-mail: oasojo@unmc.edu [Eppley Institute for Research in Cancer and Allied Diseases, 987696 Nebraska Medical Center, Omaha, NE 68198-7696 (United States); Loukas, Alex [Department of Microbiology and Tropical Medicine, The George Washington University Medical Center, Washington DC 20037 (United States); Division of Infectious Diseases and Immunology, Queensland Institute of Medical Research, Brisbane, QLD 4006 (Australia); Inan, Mehmet; Barent, Rick; Huang, Jicai; Plantz, Brad; Swanson, Amber; Gouthro, Mark; Meagher, Michael M. [Department of Chemical Engineering, The University of Nebraska-Lincoln, Lincoln, NE 68588-0643 (United States); Hotez, Peter J. [Department of Microbiology and Tropical Medicine, The George Washington University Medical Center, Washington DC 20037 (United States); Eppley Institute for Research in Cancer and Allied Diseases, 987696 Nebraska Medical Center, Omaha, NE 68198-7696 (United States)

    2005-04-01

    In order to clarify the structural basis of the pathogenesis-related-1 domain, Na-ASP-1, the first multi-domain ASP from the human hookworm parasite N. americanus, has been crystallized. 2.2 Å resolution data have been collected from a crystal belonging to the monoclinic space group P2{sub 1}. Human hookworm infection is a major cause of anemia and malnutrition in the developing world. In an effort to control hookworm infection, the Human Hookworm Vaccine Initiative has identified candidate vaccine antigens from the infective larval stage (L3) of the parasite, including a family of pathogenesis-related-1 (PR-1) proteins known as the ancylostoma-secreted proteins (ASPs). The functions of the ASPs are unknown. In addition, it is unclear why some ASPs have one while others have multiple PR-1 domains. There are no known structures of a multi-domain ASP and in an effort to remedy this situation, recombinant Na-ASP-1 has been expressed, purified and crystallized. Na-ASP-1 is a 406-amino-acid multi-domain ASP from the prevalent human hookworm parasite Necator americanus. Useful X-ray data to 2.2 Å have been collected from a crystal that belongs to the monoclinic space group P2{sub 1} with unit-cell parameters a = 67.7, b = 74.27, c = 84.60 Å, β = 112.12°. An initial molecular-replacement solution has been obtained with one monomer in the asymmetric unit.

  14. Introduced cryptic species of parasites exhibit different invasion pathways.

    Science.gov (United States)

    Miura, Osamu; Torchin, Mark E; Kuris, Armand M; Hechinger, Ryan F; Chiba, Satoshi

    2006-12-26

    Sometimes infectious agents invade and become established in new geographic regions. Others may be introduced yet never become established because of the absence of suitable hosts in the new region. This phenomenon may be particularly true for the many parasites with complex life cycles, where various life stages require different host species. Homogenization of the world's biota through human-mediated invasions may reunite hosts and parasites, resulting in disease outbreaks in novel regions. Here we use molecular genetics to differentiate invasion pathways for two digenean trematode parasites and their exotic host, the Asian mud snail, Batillaria attramentaria. All of the snail haplotypes found in introduced populations in North America were identical to haplotypes common in the areas of Japan that provided oysters for cultivation in North America, supporting the hypothesis that the snails were introduced from Japan with seed oysters. Two cryptic trematode species were introduced to North American populations in high frequencies. We found a marked reduction of genetic variation in one of these species, suggesting it experienced a bottleneck or founder event comparable to that of the host snail. In contrast, no genetic variation was lost in the other parasite species. We hypothesize that this parasite was and is dispersed naturally by migratory shorebirds and was able to establish only after the host snail, B. attramentaria, was introduced to North America. Evaluation of the nature of invasion pathways and postinvasion consequences will aid mitigation of spreading diseases of humans, livestock, and wildlife in an increasingly globalized world.

  15. Lundep, a sand fly salivary endonuclease increases Leishmania parasite survival in neutrophils and inhibits XIIa contact activation in human plasma.

    Directory of Open Access Journals (Sweden)

    Andrezza C Chagas

    2014-02-01

    Full Text Available Neutrophils are the host's first line of defense against infections, and their extracellular traps (NET were recently shown to kill Leishmania parasites. Here we report a NET-destroying molecule (Lundep from the salivary glands of Lutzomyia longipalpis. Previous analysis of the sialotranscriptome of Lu. longipalpis showed the potential presence of an endonuclease. Indeed, not only was the cloned cDNA (Lundep shown to encode a highly active ss- and dsDNAse, but also the same activity was demonstrated to be secreted by salivary glands of female Lu. longipalpis. Lundep hydrolyzes both ss- and dsDNA with little sequence specificity with a calculated DNase activity of 300000 Kunitz units per mg of protein. Disruption of PMA (phorbol 12 myristate 13 acetate- or parasite-induced NETs by treatment with recombinant Lundep or salivary gland homogenates increases parasite survival in neutrophils. Furthermore, co-injection of recombinant Lundep with metacyclic promastigotes significantly exacerbates Leishmania infection in mice when compared with PBS alone or inactive (mutagenized Lundep. We hypothesize that Lundep helps the parasite to establish an infection by allowing it to escape from the leishmanicidal activity of NETs early after inoculation. Lundep may also assist blood meal intake by lowering the local viscosity caused by the release of host DNA and as an anticoagulant by inhibiting the intrinsic pathway of coagulation.

  16. Robust inducible Cre recombinase activity in the human malaria parasite Plasmodium falciparum enables efficient gene deletion within a single asexual erythrocytic growth cycle.

    Science.gov (United States)

    Collins, Christine R; Das, Sujaan; Wong, Eleanor H; Andenmatten, Nicole; Stallmach, Robert; Hackett, Fiona; Herman, Jean-Paul; Müller, Sylke; Meissner, Markus; Blackman, Michael J

    2013-05-01

    Asexual blood stages of the malaria parasite, which cause all the pathology associated with malaria, can readily be genetically modified by homologous recombination, enabling the functional study of parasite genes that are not essential in this part of the life cycle. However, no widely applicable method for conditional mutagenesis of essential asexual blood-stage malarial genes is available, hindering their functional analysis. We report the application of the DiCre conditional recombinase system to Plasmodium falciparum, the causative agent of the most dangerous form of malaria. We show that DiCre can be used to obtain rapid, highly regulated site-specific recombination in P. falciparum, capable of excising loxP-flanked sequences from a genomic locus with close to 100% efficiency within the time-span of a single erythrocytic growth cycle. DiCre-mediated deletion of the SERA5 3' UTR failed to reduce expression of the gene due to the existence of alternative cryptic polyadenylation sites within the modified locus. However, we successfully used the system to recycle the most widely used drug resistance marker for P. falciparum, human dihydrofolate reductase, in the process producing constitutively DiCre-expressing P. falciparum clones that have broad utility for the functional analysis of essential asexual blood-stage parasite genes. © 2013 John Wiley & Sons Ltd.

  17. Genome and transcriptome studies of the protozoan parasites Trypanosoma cruzi and Giardia intestinalis

    OpenAIRE

    Franzén, Oscar

    2012-01-01

    Trypanosoma cruzi and Giardia intestinalis are two human pathogens and protozoan parasites responsible for the diseases Chagas disease and giardiasis, respectively. Both diseases cause su ering and illness in several million individuals. The former disease occurs primarily in South America and Central America, and the latter disease occurs worldwide. Current therapeutics are toxic and lack e cacy, and potential vaccines are far from the market. Increased knowledge about the bio...

  18. Characterization and Function of the Inflammatory Response to Infection by a Gastrointestinal Nematode Parasite: New Insights into Protective Th2 Responses

    Science.gov (United States)

    2006-01-01

    gastrointestinal nematode parasites;T. trichuris, T. muris , T suis. WT wild type. 1 Dissertation Introduction Background and Significance...and hosts2. Infectious parasites are responsible for a wide range of human diseases, including Leishmanisis, Malaria, Schistosomaisis, Giardia ...the gut to define more clearly protective mechanisms against gastrointestinal nematodes. Using a mouse whipworm model of Trichuris 81 muris

  19. Global issues in allergy and immunology: Parasitic infections and allergy.

    Science.gov (United States)

    Cruz, Alvaro A; Cooper, Philip J; Figueiredo, Camila A; Alcantara-Neves, Neuza M; Rodrigues, Laura C; Barreto, Mauricio L

    2017-11-01

    Allergic diseases are on the increase globally in parallel with a decrease in parasitic infection. The inverse association between parasitic infections and allergy at an ecological level suggests a causal association. Studies in human subjects have generated a large knowledge base on the complexity of the interrelationship between parasitic infection and allergy. There is evidence for causal links, but the data from animal models are the most compelling: despite the strong type 2 immune responses they induce, helminth infections can suppress allergy through regulatory pathways. Conversely, many helminths can cause allergic-type inflammation, including symptoms of "classical" allergic disease. From an evolutionary perspective, subjects with an effective immune response against helminths can be more susceptible to allergy. This narrative review aims to inform readers of the most relevant up-to-date evidence on the relationship between parasites and allergy. Experiments in animal models have demonstrated the potential benefits of helminth infection or administration of helminth-derived molecules on chronic inflammatory diseases, but thus far, clinical trials in human subjects have not demonstrated unequivocal clinical benefits. Nevertheless, there is sufficiently strong evidence to support continued investigation of the potential benefits of helminth-derived therapies for the prevention or treatment of allergic and other inflammatory diseases. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  20. Palaeopathology and genes: investigating the genetics of infectious diseases in excavated human skeletal remains and mummies from past populations.

    Science.gov (United States)

    Anastasiou, Evilena; Mitchell, Piers D

    2013-10-01

    The aim of this paper is to review the use of genetics in palaeomicrobiology, and to highlight the importance of understanding past diseases. Palaeomicrobiology is the study of disease pathogens in skeletal and mummified remains from archaeological contexts. It has revolutionarised our understanding of health in the past by enabling a deeper knowledge of the origins and evolution of many diseases that have shaped us as a species. Bacterial diseases explored include tuberculosis, leprosy, bubonic plague, typhoid, syphilis, endemic and epidemic typhus, trench fever, and Helicobacter pylori. Viral diseases discussed include influenza, hepatitis B, human papilloma virus (HPV), human T-cell lymphotrophic virus (HTLV-1) and human immunodeficiency virus (HIV). Parasitic diseases investigated include malaria, leishmaniasis, Chagas' disease, roundworm, whipworm, pinworm, Chinese liver fluke, fleas and lice. Through a better understanding of disease origins and their evolution, we can place into context how many infectious diseases are changing over time, and so help us estimate how they may change in the future. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Pentastomiasis and other parasitic zoonoses from reptiles and amphibians.

    Science.gov (United States)

    Pantchev, Nikola; Tappe, Dennis

    2011-01-01

    Reptiles are growing in popularity as pets.The colonization of reptiles and amphibians by parasites and the resulting disease conditions are the most common problems seen in captive animals.This review focuses on pentastomiasis and sparganosis, important parasitic zoonoses of reptiles and amphibians, respectively, and free living-amoebae. Humans are suitable accidental hosts for some pentastomid species (particularly Armillifer and Porocephalus). In geographical areas with special ethnics, such as in West and Central Africa, and East Asia, 8-45% of the human population can be affected. Usually the larvae are coincidentally found during abdominal surgeries. However, fatalities have been described. Extreme caution is necessary when handling infected reptiles. Ocular or cerebral sparganosis is not uncommonly found in humans in East Asia. This disease is caused by spargana, tapeworm larvae (plerocercoids) of Spirometra sp. The infection occurs when uncooked meat from reptiles or amphibians is applied to wounds or eyes and the parasites migrate directly to human tissue, or by consumption of contaminated food or water. As a consequence of the reptile's predatory behaviour, the full spectrum of endo- and ectoparasites from potential prey animals can be found as transiting parasites in the intestinal tract, e. g. Hymenolepis nana, Cryptosporidium (C.) muris, C parvum or Capillaria hepatica. Occasionally, free-living amoebae are also found in reptile faeces (Acanthamoeba, Naegleria, Hartmanella, Vahlkampfia or Echinamoeba sp.).

  2. Contribution of draft cattle to rural livelihoods in a district of southeastern Uganda endemic for bovine parasitic diseases: an economic evaluation.

    Science.gov (United States)

    Okello, Walter O; Muhanguzi, Dennis; MacLeod, Ewan T; Welburn, Susan C; Waiswa, Charles; Shaw, Alexandra P

    2015-11-05

    A study was conducted in Tororo District in eastern Uganda to assess the socio-economic contribution of draft cattle to rural livelihoods. The aim of the study was to empirically quantify the economic value of draft cattle thus contributing to understanding the impact of endemic parasitic diseases of cattle on livestock productivity and subsequently household income, labor and food security. A total of 205 draft cattle keeping households (n = 205) were randomly selected and structured household questionnaires were administered, focusing on work oxen use, productivity, inputs and outputs. The data obtained was analyzed using standard statistical methods and used to calculate the gross margin from the draft cattle enterprise. Secondary data were obtained from focus group discussions and key informant interviews and these were analyzed using Bayesian methods. The study showed that, apart from being labor saving, the use of animal traction is highly profitable with the gross margin per year from the use of draft cattle amounting to 245 United States dollars per work oxen owning household. The cash obtained from hiring out draft animals was equivalent to nearly a quarter of the average local household's monetary receipts. It also revealed that endemic bovine parasitic diseases such as trypanosomiasis and tick-borne diseases reduced draft cattle output by 20.9 % and potential household income from the use of draft oxen by 32.2 %. The presence of endemic cattle diseases in rural Uganda is adversely affecting the productivity of draft cattle, which in turn affects household income, labor and ultimately food security. This study highlights the contribution of draft cattle to rural livelihoods, thus increasing the expected impact of cost-effective control strategies of endemic production limiting livestock diseases in Uganda.

  3. Occurrence of Intestinal Parasitic Contamination in Select Consumed Local Raw Vegetables and Fruits in Kuantan, Pahang

    Science.gov (United States)

    Yusof, Afzan Mat; Mohammad, Mardhiah; Abdullahi, Muna Abshir; Mohamed, Zeehaida; Zakaria, Robaiza; Wahab, Ridhwan Abdul

    2017-01-01

    Intestinal parasitic infections are one of the most common causes of human diseases that result in serious health and economic issues in many developing and developed countries. Raw vegetables and fruits play an important role in transmitting parasites to humans. Hence, the aim of this study was to investigate the parasitological contamination of select commonly consumed local leafy vegetables and fruits in Kuantan, Malaysia. One kilogram of locally consumed raw vegetables and fruits were collected randomly from the Kuantan wet market (Pasar Tani) during the monsoon season (November 2014–January 2015) and the dry season (February 2015–April 2015). A standard wet mount procedure and modified Ziehl-Neelsen staining were used for the detection of parasites. In the present study, the examination of vegetables revealed five different parasite species. The vegetable samples collected from Kuantan’s wet market were positive for both helminthes and protozoa. However, the fruits samples were negative for parasitic contamination. Pegaga was the most contaminated leafy vegetable in this study, and Strongyloides was the parasite found most frequently. Furthermore, there was a high diversity in the type of parasites observed during the dry season compared to the monsoon season. Therefore, further action should be taken to reduce the occurrence of parasitic contamination in vegetables by implementing the principles of good agricultural practice and improving water treatment efficacy. PMID:28228914

  4. Parasitic helminths: a pharmacopeia of anti-inflammatory molecules.

    Science.gov (United States)

    Johnston, M J G; MacDonald, J A; McKay, D M

    2009-02-01

    Infection with parasitic helminths takes a heavy toll on the health and well-being of humans and their domestic livestock, concomitantly resulting in major economic losses. Analyses have consistently revealed bioactive molecules in extracts of helminths or in their excretory/secretory products that modulate the immune response of the host. It is our view that parasitic helminths are an untapped source of immunomodulatory substances that, in pure form, could become new drugs (or models for drug design) to treat disease. Here, we illustrate the range of immunomodulatory molecules in selected parasitic trematodes, cestodes and nematodes, their impact on the immune cells in the host and how the host may recognize these molecules. There are many examples of the partial characterization of helminth-derived immunomodulatory molecules, but these have not yet translated into new drugs, reflecting the difficulty of isolating and fully characterizing proteins, glycoproteins and lipid-based molecules from small amounts of parasite material. However, this should not deter the investigator, since analytical techniques are now being used to accrue considerable structural information on parasite-derived molecules, even when only minute quantities of tissue are available. With the introduction of methodologies to purify and structurally-characterize molecules from small amounts of tissue and the application of high throughput immunological assays, one would predict that an assessment of parasitic helminths will yield a variety of novel drug candidates in the coming years.

  5. Global Mammal Parasite Database version 2.0.

    Science.gov (United States)

    Stephens, Patrick R; Pappalardo, Paula; Huang, Shan; Byers, James E; Farrell, Maxwell J; Gehman, Alyssa; Ghai, Ria R; Haas, Sarah E; Han, Barbara; Park, Andrew W; Schmidt, John P; Altizer, Sonia; Ezenwa, Vanessa O; Nunn, Charles L

    2017-05-01

    Illuminating the ecological and evolutionary dynamics of parasites is one of the most pressing issues facing modern science, and is critical for basic science, the global economy, and human health. Extremely important to this effort are data on the disease-causing organisms of wild animal hosts (including viruses, bacteria, protozoa, helminths, arthropods, and fungi). Here we present an updated version of the Global Mammal Parasite Database, a database of the parasites of wild ungulates (artiodactyls and perissodactyls), carnivores, and primates, and make it available for download as complete flat files. The updated database has more than 24,000 entries in the main data file alone, representing data from over 2700 literature sources. We include data on sampling method and sample sizes when reported, as well as both "reported" and "corrected" (i.e., standardized) binomials for each host and parasite species. Also included are current higher taxonomies and data on transmission modes used by the majority of species of parasites in the database. In the associated metadata we describe the methods used to identify sources and extract data from the primary literature, how entries were checked for errors, methods used to georeference entries, and how host and parasite taxonomies were standardized across the database. We also provide definitions of the data fields in each of the four files that users can download. © 2017 by the Ecological Society of America.

  6. Pathogens and politics: further evidence that parasite prevalence predicts authoritarianism.

    Science.gov (United States)

    Murray, Damian R; Schaller, Mark; Suedfeld, Peter

    2013-01-01

    According to a "parasite stress" hypothesis, authoritarian governments are more likely to emerge in regions characterized by a high prevalence of disease-causing pathogens. Recent cross-national evidence is consistent with this hypothesis, but there are inferential limitations associated with that evidence. We report two studies that address some of these limitations, and provide further tests of the hypothesis. Study 1 revealed that parasite prevalence strongly predicted cross-national differences on measures assessing individuals' authoritarian personalities, and this effect statistically mediated the relationship between parasite prevalence and authoritarian governance. The mediation result is inconsistent with an alternative explanation for previous findings. To address further limitations associated with cross-national comparisons, Study 2 tested the parasite stress hypothesis on a sample of traditional small-scale societies (the Standard Cross-Cultural Sample). Results revealed that parasite prevalence predicted measures of authoritarian governance, and did so even when statistically controlling for other threats to human welfare. (One additional threat-famine-also uniquely predicted authoritarianism.) Together, these results further substantiate the parasite stress hypothesis of authoritarianism, and suggest that societal differences in authoritarian governance result, in part, from cultural differences in individuals' authoritarian personalities.

  7. Entomologic index for human risk of Lyme disease.

    Science.gov (United States)

    Mather, T N; Nicholson, M C; Donnelly, E F; Matyas, B T

    1996-12-01

    An entomologic index based on density estimates of Lyme disease spirochete-infected nymphal deer ticks (lxodes scapularis) was developed to assess human risk of Lyme disease. The authors used a standardized protocol to determine tick density and infection in numerous forested sites in six Rhode Island towns. An entomologic risk index calculated for each town was compared with the number of human Lyme disease cases reported to the Rhode Island State Health Department for the same year. A strong positive relation between entomologic risk index and the Lyme disease case rate for each town suggested that the entomologic index was predictive of Lyme disease risk.

  8. Subversion of Immunity by Leishmania amazonensis Parasites: Possible Role of Phosphatidylserine as a Main Regulator

    Directory of Open Access Journals (Sweden)

    Joao Luiz Mendes Wanderley

    2012-01-01

    Full Text Available Leishmania amazonensis parasites cause progressive disease in most inbred mouse strains and are associated with the development of diffuse cutaneous leishmaniasis in humans. The poor activation of an effective cellular response is correlated with the ability of these parasites to infect mononuclear phagocytic cells without triggering their activation or actively suppressing innate responses of these cells. Here we discuss the possible role of phosphatidylserine exposure by these parasites as a main regulator of the mechanism underlying subversion of the immune system at different steps during the infection.

  9. Nutrition, epigenetic mechanisms, and human disease

    National Research Council Canada - National Science Library

    Maulik, Nilanjana; Maulik, Gautam

    2011-01-01

    .... The text discusses the basics of nutrigenomics and epigenetic regulation, types of nutrition influencing genetic imprinting, and the role of nutrition in modulating an individual's predisposition to disease...

  10. Parasitic infections of the external eye.

    Science.gov (United States)

    Pahuja, Shivani; Puranik, Charuta; Jelliti, Bechir; Khairallah, Moncef; Sangwan, Virender S

    2013-08-01

    To review the published literature on parasitic infections of external eye. Published articles and case reports on parasitic infections of external eye were reviewed and relevant information was collected. Parasitic infections of the eye are rare. However, being more commonly seen in developing nations, they require active measures for screening, diagnosis, and therapy. Parasites of importance causing external ocular disease are protozoan parasites, such as Leishmania; metazoans, such as nematodes (roundworms), cestodes (tapeworms), and trematodes (flatworms); or ectoparasites, such as Phthirus pubis and Demodex.

  11. Fauna of Zoontic Parasites of Stray Dogs in Yasouj Suburbs in 2008

    Directory of Open Access Journals (Sweden)

    A Moshfe

    2011-04-01

    Full Text Available Introduction & Objective: Dogs are among the closest animals to human residents and can by useful for human. A few of zoontic diseases are prevalent in Iran. Dogs are the reservoirs of many of these zoonosis and a major role in transmission of infection. The aim of this study was to determine the zoonotic parasitic fauna of stray dogs in Yasuj Materials & Methods: In this descriptive study which was conducted at Yasuj suburbs in 2008, 25 dogs’ corpses were necropsied and their tissues were studied for parasitic infections. Collected parasites were placed in special containers and stained for genus and species diagnosis based on their morphological features. The collected data were analyzed with the SPSS software, using descriptive analysis. Results: Of the 25 studied corpses, 23 dogs were infected with at least one parasite. Helminthic infections of dogs were consisted of: Taenia hydatigena, Mesocestoides sp., Echinococcus granulosus, Dipylidium caninum, Macracanthorhynchus hirudinaceus and Spirocerca lupi. Conclusion: Four of six detected helminthes in in dogs in this study are zoonotic parasites which are important in human diseases. Among them larval stage of Echinococcus granulosus which causes hydatid cyst disease in human is very important. Control programs should be implemented in this region to prevent these zoonotic diseases.

  12. Multinational corporations and infectious disease: Embracing human rights management techniques.

    Science.gov (United States)

    Salcito, Kendyl; Singer, Burton H; Weiss, Mitchell G; Winkler, Mirko S; Krieger, Gary R; Wielga, Mark; Utzinger, Jürg

    2014-01-01

    Global health institutions have called for governments, international organisations and health practitioners to employ a human rights-based approach to infectious diseases. The motivation for a human rights approach is clear: poverty and inequality create conditions for infectious diseases to thrive, and the diseases, in turn, interact with social-ecological systems to promulgate poverty, inequity and indignity. Governments and intergovernmental organisations should be concerned with the control and elimination of these diseases, as widespread infections delay economic growth and contribute to higher healthcare costs and slower processes for realising universal human rights. These social determinants and economic outcomes associated with infectious diseases should interest multinational companies, partly because they have bearing on corporate productivity and, increasingly, because new global norms impose on companies a responsibility to respect human rights, including the right to health. We reviewed historical and recent developments at the interface of infectious diseases, human rights and multinational corporations. Our investigation was supplemented with field-level insights at corporate capital projects that were developed in areas of high endemicity of infectious diseases, which embraced rights-based disease control strategies. Experience and literature provide a longstanding business case and an emerging social responsibility case for corporations to apply a human rights approach to health programmes at global operations. Indeed, in an increasingly globalised and interconnected world, multinational corporations have an interest, and an important role to play, in advancing rights-based control strategies for infectious diseases. There are new opportunities for governments and international health agencies to enlist corporate business actors in disease control and elimination strategies. Guidance offered by the United Nations in 2011 that is widely embraced

  13. Social and environmental health determinants and their relationship with parasitic diseases in asymptomatic children from a shantytown in Buenos Aires, Argentina

    Science.gov (United States)

    Garbossa, Graciela; Pía Buyayisqui, María; Geffner, Laura; López Arias, Ludmila; de la Fournière, Sofía; Haedo, Ana S; Marconi, Adela E; Frid, Juan C; Nesse, Alcira B; Bordoni, Noemí

    2013-01-01

    Health inequities are a common problem for all countries and are the result of not only adverse social conditions but also poor public policies. Today chronic diseases represent the most relevant threats and are a current challenge. Parasitic infections, a leading cause of child morbidity affecting low-income populations, can be transmitted because of an unhealthy environment. Notwithstanding, scarce data have been published on the epidemiological profile of intestinal parasitoses in asymptomatic children living in shantytowns. Vulnerable populations settled in slums are growing in Argentina, particularly in Buenos Aires city. Consequently, this work intended to screen healthy carriers of enteric parasites and determine the epidemiologic profile in asymptomatic children residing in one of those communities, to explore risk factors associated with the transmission of parasites, and to initiate a basic health education campaign to promote healthy behavior in the community. Fecal samples (n = 138) were analyzed by conventional parasitological methods and a survey gathered data on symptoms, family composition, and environmental and hygiene-related variables. High prevalence of feco-orally-transmitted parasitoses (83.3%) and polyparasitism were remarkable findings. The main environmental health determinants were those related to excreta disposal and water provision. Health promotion actions were performed through the diffusion of a set of posters with iconic images and brief messages for health education. Results suggest the need for an environmental sanitation policy to complement health promotion actions. It is essential to spread the results of investigations that address inequities and social determinants of health in order to integrate data with local political processes and alert on acceptable actions for developing appropriate interventions. PMID:23683369

  14. The genus Malassezia and human disease

    Directory of Open Access Journals (Sweden)

    Inamadar A

    2003-07-01

    Full Text Available Sabouraud's Pityrosporum is now recognized as Malassezia. With taxonomic revision of the genus, newer species have been included. The role of this member of the normal human skin flora in different cutaneous and systemic disorders is becoming clearer. The immunological responses it induces in the human body are conflicting and their relevance to clinical features is yet to be explored.

  15. Using Human Induced Pluripotent Stem Cells to Model Skeletal Diseases.

    Science.gov (United States)

    Barruet, Emilie; Hsiao, Edward C

    2016-01-01

    Musculoskeletal disorders affecting the bones and joints are major health problems among children and adults. Major challenges such as the genetic origins or poor diagnostics of severe skeletal disease hinder our understanding of human skeletal diseases. The recent advent of human induced pluripotent stem cells (human iPS cells) provides an unparalleled opportunity to create human-specific models of human skeletal diseases. iPS cells have the ability to self-renew, allowing us to obtain large amounts of starting material, and have the potential to differentiate into any cell types in the body. In addition, they can carry one or more mutations responsible for the disease of interest or be genetically corrected to create isogenic controls. Our work has focused on modeling rare musculoskeletal disorders including fibrodysplasia ossificans progressive (FOP), a congenital disease of increased heterotopic ossification. In this review, we will discuss our experiences and protocols differentiating human iPS cells toward the osteogenic lineage and their application to model skeletal diseases. A number of critical challenges and exciting new approaches are also discussed, which will allow the skeletal biology field to harness the potential of human iPS cells as a critical model system for understanding diseases of abnormal skeletal formation and bone regeneration.

  16. Modeling human gastrointestinal inflammatory diseases using microphysiological culture systems.

    Science.gov (United States)

    Hartman, Kira G; Bortner, James D; Falk, Gary W; Ginsberg, Gregory G; Jhala, Nirag; Yu, Jian; Martín, Martín G; Rustgi, Anil K; Lynch, John P

    2014-09-01

    Gastrointestinal illnesses are a significant health burden for the US population, with 40 million office visits each year for gastrointestinal complaints and nearly 250,000 deaths. Acute and chronic inflammations are a common element of many gastrointestinal diseases. Inflammatory processes may be initiated by a chemical injury (acid reflux in the esophagus), an infectious agent (Helicobacter pylori infection in the stomach), autoimmune processes (graft versus host disease after bone marrow transplantation), or idiopathic (as in the case of inflammatory bowel diseases). Inflammation in these settings can contribute to acute complaints (pain, bleeding, obstruction, and diarrhea) as well as chronic sequelae including strictures and cancer. Research into the pathophysiology of these conditions has been limited by the availability of primary human tissues or appropriate animal models that attempt to physiologically model the human disease. With the many recent advances in tissue engineering and primary human cell culture systems, it is conceivable that these approaches can be adapted to develop novel human ex vivo systems that incorporate many human cell types to recapitulate in vivo growth and differentiation in inflammatory microphysiological environments. Such an advance in technology would improve our understanding of human disease progression and enhance our ability to test for disease prevention strategies and novel therapeutics. We will review current models for the inflammatory and immunological aspects of Barrett's esophagus, acute graft versus host disease, and inflammatory bowel disease and explore recent advances in culture methodologies that make these novel microphysiological research systems possible. © 2014 by the Society for Experimental Biology and Medicine.

  17. Chronic Inflammatory Periodontal Disease in Patients with Human Immunodeficiency Virus.

    OpenAIRE

    Vania López Rodríguez; Emilio Carpio Muñoz; Vicente Fardales Macías; Iralys Benítez Guzmán

    2009-01-01

    Background: The Chronic Inflammatory Periodontal Disease is related with multiple risk factors. Those patients with human immunodeficiency virus have higher risk of presenting this disease and it is usually more serious in these cases. Objective: To describe the prevalence of Chronic Inflammatory Periodontal Disease in patients with HIV. Methods: Descriptive, observational, cross-sectional study including patients with HIV in Sancti Spiritus province. The occurrence of the disease was determi...

  18. Extracellular RNAs: development as biomarkers of human disease

    Directory of Open Access Journals (Sweden)

    Joseph F. Quinn

    2015-08-01

    Full Text Available Ten ongoing studies designed to test the possibility that extracellular RNAs may serve as biomarkers in human disease are described. These studies, funded by the NIH Common Fund Extracellular RNA Communication Program, examine diverse extracellular body fluids, including plasma, serum, urine and cerebrospinal fluid. The disorders studied include hepatic and gastric cancer, cardiovascular disease, chronic kidney disease, neurodegenerative disease, brain tumours, intracranial haemorrhage, multiple sclerosis and placental disorders. Progress to date and the plans for future studies are outlined.

  19. Disease emergence and resurgence—the wildlife-human connection

    Science.gov (United States)

    Friend, Milton; Hurley, James W.; Nol, Pauline; Wesenberg, Katherine

    2006-01-01

    In 2000, the Global Outbreak Alert and Response Network (GOARN) was organized as a global disease watchdog group to coordinate disease outbreak information and health crisis response. The World Health Organization (WHO) is the headquarters for this network. Understandably, the primary focus for WHO is human health. However, diseases such as the H5N1 avian influenza epizootic in Asian bird populations demonstrate the need for integrating knowledge about disease emergence in animals and in humans.Aside from human disease concerns, H5N1 avian influenza has major economic consequences for the poultry industry worldwide. Many other emerging diseases, such as severe acute respiratory syndrome (SARS), monkeypox, Ebola fever, and West Nile fever, also have an important wildlife component. Despite these wildlife associations, the true integration of the wildlife component in approaches towards disease emergence remains elusive. This separation between wildlife and other species’ interests is counterproductive because the emergence of zoonotic viruses and other pathogens maintained by wildlife reservoir hosts is poorly understood.This book is about the wildlife component of emerging diseases. It is intended to enhance the reader’s awareness of the role of wildlife in disease emergence. By doing so, perhaps a more holistic approach to disease prevention and control will emerge for the benefit of human, domestic animal, and free-ranging wildlife populations alike. The perspectives offered are influenced by more than four decades of my experiences as a wildlife disease practitioner. Although wildlife are victims to many of the same disease agents affecting humans and domestic animals, many aspects of disease in free-ranging wildlife require different approaches than those commonly applied to address disease in humans or domestic animals. Nevertheless, the broader community of disease investigators and health care professionals has largely pursued a separatist approach for

  20. Targeting channels and transporters in protozoan parasite infections

    Science.gov (United States)

    Meier, Anna; Erler, Holger; Beitz, Eric

    2018-03-01

    Infectious diseases caused by pathogenic protozoa are among the most significant causes of death in humans. Therapeutic options are scarce and massively challenged by the emergence of resistant parasite strains. Many of the current anti-parasite drugs target soluble enzymes, generate unspecific oxidative stress, or act by an unresolved mechanism within the parasite. In recent years, collections of drug-like compounds derived from large-scale phenotypic screenings, such as the malaria or pathogen box, have been made available to researchers free of charge boosting the identification of novel promising targets. Remarkably, several of the compound hits have been found to inhibit membrane proteins at the periphery of the parasites, i.e. channels and transporters for ions and metabolites. In this review, we will focus on the progress made on targeting channels and transporters at different levels and the potential for use against infections with apicomplexan parasites mainly Plasmodium spp. (malaria) and Toxoplasma gondii (toxoplasmosis), with kinetoplastids Trypanosoma brucei (sleeping sickness), Trypanosoma cruzi (Chagas disease) and Leishmania ssp. (leishmaniasis), and the amoeba Entamoeba histolytica (amoebiasis).

  1. One stimulus-Two responses: Host and parasite life-history variation in response to environmental stress.

    Science.gov (United States)

    Gleichsner, Alyssa M; Cleveland, Jessica A; Minchella, Dennis J

    2016-11-01

    Climate change stressors will place different selective pressures on both parasites and their hosts, forcing individuals to modify their life-history strategies and altering the distribution and prevalence of disease. Few studies have investigated whether parasites are able to respond to host stress and respond by varying their reproductive schedules. Additionally, multiple environmental stressors can limit the ability of a host to respond adaptively to parasite infection. This study compared both host and parasite life-history parameters in unstressed and drought-stressed environments using the human parasite, Schistosoma mansoni, in its freshwater snail intermediate host. Snail hosts infected with the parasite demonstrated a significant reproductive burst during the prepatent period (fecundity compensation), but that response was absent in a drought-stressed environment. This is the first report of the elimination of host fecundity compensation to parasitism when exposed to additional environmental stress. More surprisingly, we found that infections in drought-stressed snails had significantly higher parasite reproductive outputs than infections in unstressed snails. The finding suggests that climate change may alter the infection dynamics of this human parasite. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  2. Isolation of Intestinal Parasites of Public Health Importance from Cockroaches (Blattella germanica) in Jimma Town, Southwestern Ethiopia.

    Science.gov (United States)

    Hamu, Haji; Debalke, Serkadis; Zemene, Endalew; Birlie, Belay; Mekonnen, Zeleke; Yewhalaw, Delenasaw

    2014-01-01

    Cockroaches are claimed to be mechanical transmitters of disease causing microorganisms such as intestinal parasites, bacteria, fungi, and viruses. This study assessed the potential of the German cockroach Blattella germanica in the mechanical transmission of intestinal parasites of public health importance. A total of 2010 cockroaches were collected from 404 households in Jimma Town, southwestern Ethiopia. All the collected cockroaches were identified to species as B. germanica. The contents of their gut and external body parts were examined for the presence of intestinal parasites. Overall, 152 (75.6%) of the 210 batches were found to harbor at least one species of human intestinal parasite. Ascaris lumbricoides, Trichuris trichiura, Taenia spp, Strongyloides-like parasite, Entamoeba histolytica/dispar/moshkovski, Giardia duodenalis and Balantidium coli were detected from gut contents. Moreover, parasites were also isolated from the external surface in 22 (10.95%) of the batches. There was significant difference in parasite carriage rate of the cockroaches among the study sites (P = 0.013). In conclusion, B. germanica was found to harbor intestinal parasites of public health importance. Hence, awareness on the potential role of cockroaches in the mechanical transmission of human intestinal parasites needs to be created. Moreover, further identification of the Strongyloides-like worm is required using molecular diagnostics.

  3. Isolation of Intestinal Parasites of Public Health Importance from Cockroaches (Blattella germanica in Jimma Town, Southwestern Ethiopia

    Directory of Open Access Journals (Sweden)

    Haji Hamu

    2014-01-01

    Full Text Available Cockroaches are claimed to be mechanical transmitters of disease causing microorganisms such as intestinal parasites, bacteria, fungi, and viruses. This study assessed the potential of the German cockroach Blattella germanica in the mechanical transmission of intestinal parasites of public health importance. A total of 2010 cockroaches were collected from 404 households in Jimma Town, southwestern Ethiopia. All the collected cockroaches were identified to species as B. germanica. The contents of their gut and external body parts were examined for the presence of intestinal parasites. Overall, 152 (75.6% of the 210 batches were found to harbor at least one species of human intestinal parasite. Ascaris lumbricoides, Trichuris trichiura, Taenia spp, Strongyloides-like parasite, Entamoeba histolytica/dispar/moshkovski, Giardia duodenalis and Balantidium coli were detected from gut contents. Moreover, parasites were also isolated from the external surface in 22 (10.95% of the batches. There was significant difference in parasite carriage rate of the cockroaches among the study sites (P=0.013. In conclusion, B. germanica was found to harbor intestinal parasites of public health importance. Hence, awareness on the potential role of cockroaches in the mechanical transmission of human intestinal parasites needs to be created. Moreover, further identification of the Strongyloides-like worm is required using molecular diagnostics.

  4. [Tick-borne diseases].

    Science.gov (United States)

    Tissot Dupont, H; Raoult, D

    1993-05-01

    Due to their worldwide distribution, from hottest to coldest climates, and due to their behaviour, ticks are capable of transmitting numerous human and animal bacterial viral or parasitous diseases. Depending on the disease, they play the role of biological vector or intermediate host. In France, six tick borne diseases are of epidemiologic importance. Q fever (not often tick-borne), Mediterranean Spotted Fever, Lyme disease, Turalemia (human and animal), Babesiosis and Tick-borne Viral Encephalitis.

  5. Disease Human - MDC_CardiovascularMortality2006

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Polygon feature class based on Zip Code boundaries showing the rate of deaths due to major cardiovascular diseases per 1000 residents of Miami-Dade County in 2006.

  6. Disease Human - MDC_CLRDMortality2006

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Polygon feature class based on Zip Code boundaries showing the rate of deaths per 100,000 residents due to Chronic Lower Respiratory Disease (CLRD) in Miami-Dade...

  7. Expressão das citoceratinas em dermatoses infecto- parasitárias associadas à hiperplasia epidérmica Expression of the cytokeratins in infectious and parasitic skin diseases associated with epidermal hyperplasia

    Directory of Open Access Journals (Sweden)

    Maria Christina Marques Nogueira-Castañon

    2004-12-01

    Full Text Available FUNDAMENTOS: As citoceratinas(C são as proteínas estruturais mais importantes das células epiteliais e exibem a maior heterogeneidade dentre todas as proteínas dos filamentos intermediários. Seu estudo através de imunomarcação possibilita a análise estrutural do citoesqueleto em vários afecções neoplásicas e inflamatórias. OBJETIVOS: Verificar o padrão imuno-histoquímico da expressão das citoceratinas na epiderme de doenças infecto-parasitárias associadas à hiperplasia escamosa. MÉTODOS: Cortes histológicos obtidos de tecidos pré-fixados e incluidos em parafina à partir de lesões de cromomicose, paracoccidioidomicose, leishmaniose e condiloma acuminado foram marcados com os anticorpos DEK10, LL025, LL002 e AE1 pela técnica de imunoperoxidase (avidina-biotina. RESULTADOS: A análise de áreas com intensidade variável de hiperplasia epidérmica presentes nos fragmentos mostrou exclusivamente e/ou predominantemente nas quatro doenças: ausência de expressão da C10 nas áreas de hiperplasia intensa e retardo da expressão nas áreas de hiperplasia moderada e/ou ausente; padrão suprabasal de marcação para a C16 independentemente do grau de hiperplasia como também, liberação de epítopos suprabasais para os marcadores LL002 (C14 e AE1 (C10,14,16,19. CONCLUSÕES: As modificações indicam que, independentemente da natureza do agente etiológico e do grau de hiperplasia presente, ocorrem alterações na diferenciação e proliferação do ceratinócito.BACKGROUND: Cytokeratins (K are the major structural proteins of epithelial cells and they display the greatest heterogeneity of all intermediate filament proteins. The study of many isolated cytokeratins by immunomarcation enables the structural verification of the cytoskeleton in many neoplastic and inflammatory diseases. OBJECTIVE: To verify the immunohistochemical pattern of cytokeratin expression in infectious and parasitic diseases associated with squamous

  8. Galactolipids from Bauhinia racemosa as a new class of antifilarial agents against human lymphatic filarial parasite, Brugia malayi.

    Science.gov (United States)

    Sashidhara, Koneni V; Singh, Suriya P; Misra, Sweta; Gupta, Jyoti; Misra-Bhattacharya, Shailja

    2012-04-01

    Bioassay guided fractionation of ethanolic extract of the leaves of Bauhinia racemosa led to the isolation of galactolipid and catechin class of the compounds (1-7) from the most active n-butanol fraction (F4). Among the active galactolipids, 1 emerged as the lead molecule which was active on both forms of lymphatic filarial parasite, Brugia malayi. It was found to be better than the standard drug ivermectin and diethylcarbamazine (DEC) in terms of dose and efficacy. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  9. Parasites in Forensic Science: a historic perspective

    Science.gov (United States)

    Cardoso, Rita; Alves, Helena; Richter, Joachim; Botelho, Monica C

    Parasites show a great potential to Forensic Science. Forensic Science is the application of any science and methodology to the legal system. The forensic scientist collects and analyses the physical evidence and produce a report of the results to the court. A parasite is an organism that lives at the expense of another and they exist in any ecosystem. Parasites are the cause of many important diseases. The forensic scientists can use the parasites to identify a crime scene, to determine the murder weapon or simply identify an individual. The applications for parasites in the Forensic Science can be many and more studies should be made in Forensic Parasitology. The most important parasites in Forensic Science are helminths specifically schistosomes. Through history there are many cases where schistosomes were described in autopsies and it was related to the cause of death. Here we review the applications of parasites in Forensic Science and its importance to the forensic scientist.

  10. Emerging role of mitophagy in human diseases and physiology.

    Science.gov (United States)

    Um, Jee-Hyun; Yun, Jeanho

    2017-06-01

    Mitophagy is a process of selective removal of damaged or unnecessary mitochondria using autophagic machinery. Mitophagy plays an essential role in maintaining mitochondrial quality control and homeostasis. Mitochondrial dysfunctions and defective mitophagy in neurodegenerative diseases, cancer, and metabolic diseases indicate a close link between human disease and mitophagy. Furthermore, recent studies showing the involvement of mitophagy in differentiation and development, suggest that mitophagy may play a more active role in controlling cellular functions. A better understanding of mitophagy will provide insights about human disease and offer novel chance for treatment. This review mainly focuses on the recent implications for mitophagy in human diseases and normal physiology. [BMB Reports 2017; 50(6): 299-307].

  11. In vitro ovicidal and cestocidal effects of toxins from Bacillus thuringiensis on the canine and human parasite Dipylidium caninum.

    Science.gov (United States)

    Peña, Guadalupe; Aguilar Jiménez, Fortino Agustín; Hallal-Calleros, Claudia; Morales-Montor, Jorge; Hernández-Velázquez, Víctor Manuel; Flores-Pérez, Fernando Iván

    2013-01-01

    Bacillus thuringiensis is a gram-positive soil-dwelling bacterium that is commonly used as a biological pesticide. This bacterium may also be used for biological control of helminth parasites in domestic animals. In this study, we evaluated the possible ovicidal and cestocidal effects of a total protein extract of B. thuringiensis native strains on the zoonotic cestode parasite of dogs, Dipylidium caninum (D. caninum). Dose and time response curves were determined by coincubating B. thuringiensis proteins at concentration ranging from 100 to 1000 μ g/mL along with 4000 egg capsules of D. caninum. Egg viability was evaluated using the trypan blue exclusion test. The lethal concentration of toxins on eggs was 600 μ g/ml, and the best incubation time to produce this effect was 3 h. In the adult stage, the motility and the thickness of the tegument were used as indicators of damage. The motility was inhibited by 100% after 8 hours of culture compared to the control group, while the thickness of the cestode was reduced by 34%. Conclusively, proteins of the strain GP526 of B. thuringiensis directly act upon D. caninum showing ovicidal and cestocidal effects. Thus, B. thuringiensis is proposed as a potential biological control agent against this zoonosis.

  12. In Vitro Ovicidal and Cestocidal Effects of Toxins from Bacillus thuringiensis on the Canine and Human Parasite Dipylidium caninum

    Directory of Open Access Journals (Sweden)

    Guadalupe Peña

    2013-01-01

    Full Text Available Bacillus thuringiensis is a gram-positive soil-dwelling bacterium that is commonly used as a biological pesticide. This bacterium may also be used for biological control of helminth parasites in domestic animals. In this study, we evaluated the possible ovicidal and cestocidal effects of a total protein extract of B. thuringiensis native strains on the zoonotic cestode parasite of dogs, Dipylidium caninum (D. caninum. Dose and time response curves were determined by coincubating B. thuringiensis proteins at concentration ranging from 100 to 1000 μg/mL along with 4000 egg capsules of D. caninum. Egg viability was evaluated using the trypan blue exclusion test. The lethal concentration of toxins on eggs was 600 μg/ml, and the best incubation time to produce this effect was 3 h. In the adult stage, the motility and the thickness of the tegument were used as indicators of damage. The motility was inhibited by 100% after 8 hours of culture compared to the control group, while the thickness of the cestode was reduced by 34%. Conclusively, proteins of the strain GP526 of B. thuringiensis directly act upon D. caninum showing ovicidal and cestocidal effects. Thus, B. thuringiensis is proposed as a potential biological control agent against this zoonosis.

  13. Human glia can both induce and rescue aspects of disease phenotype in Huntington disease

    DEFF Research Database (Denmark)

    Benraiss, Abdellatif; Wang, Su; Herrlinger, Stephanie

    2016-01-01

    The causal contribution of glial pathology to Huntington disease (HD) has not been heavily explored. To define the contribution of glia to HD, we established human HD glial chimeras by neonatally engrafting immunodeficient mice with mutant huntingtin (mHTT)-expressing human glial progenitor cells...... chimeras are hyperexcitable. Conversely, normal glia can ameliorate disease phenotype in transgenic HD mice, as striatal transplantation of normal glia rescues aspects of electrophysiological and behavioural phenotype, restores interstitial potassium homeostasis, slows disease progression and extends...

  14. Vitamins in the prevention of human diseases

    National Research Council Canada - National Science Library

    Herrmann, Wolfgang, Prof; Obeid, Rima

    2011-01-01

    ... in ancient Egypt. One-sided nutrition, smoking, alcohol, genetic factors, and even geographical origin interfere with our dietary intake of the vitamins. Insufficient vitamin intake can impact our health and contribute significantly to the development of diseases. This book offers expert reviews and judgements on the role of vitamins in health and ...

  15. Exposure to Human Immunodeficiency Disease. What Precautions ...

    African Journals Online (AJOL)

    Background: The Human Immunodeficiency Virus (HIV) epidemic is more pronounced in sub-Saharan Africa. The ever-increasing prevalence of HIV infection and the continued improvement in clinical management has increased the likelihood of these patients being managed by healthcare workers. The aim of the review ...

  16. Host-Parasite Relationship in Cystic Echinococcosis: An Evolving Story

    Science.gov (United States)

    Siracusano, Alessandra; Delunardo, Federica; Teggi, Antonella; Ortona, Elena

    2012-01-01

    The larval stage of Echinococcus granulosus causes cystic echinococcosis, a neglected infectious disease that constitutes a major public health problem in developing countries. Despite being under constant barrage by the immune system, E. granulosus modulates antiparasite immune responses and persists in the human hosts with detectable humoral and cellular responses against the parasite. In vitro and in vivo immunological approaches, together with molecular biology and immunoproteomic technologies, provided us exciting insights into the mechanisms involved in the initiation of E. granulosus infection and the consequent induction and regulation of the immune response. Although the last decade has clarified many aspects of host-parasite relationship in human cystic echinococcosis, establishing the full mechanisms that cause the disease requires more studies. Here, we review some of the recent developments and discuss new avenues in this evolving story of E. granulosus infection in man. PMID:22110535

  17. Host-Parasite Relationship in Cystic Echinococcosis: An Evolving Story

    Directory of Open Access Journals (Sweden)

    Alessandra Siracusano

    2012-01-01

    Full Text Available The larval stage of Echinococcus granulosus causes cystic echinococcosis, a neglected infectious disease that constitutes a major public health problem in developing countries. Despite being under constant barrage by the immune system, E. granulosus modulates antiparasite immune responses and persists in the human hosts with detectable humoral and cellular responses against the parasite. In vitro and in vivo immunological approaches, together with molecular biology and immunoproteomic technologies, provided us exciting insights into the mechanisms involved in the initiation of E. granulosus infection and the consequent induction and regulation of the immune response. Although the last decade has clarified many aspects of host-parasite relationship in human cystic echinococcosis, establishing the full mechanisms that cause the disease requires more studies. Here, we review some of the recent developments and discuss new avenues in this evolving story of E. granulosus infection in man.

  18. Skin Diseases: Cross-section of human skin

    Science.gov (United States)

    Skip Navigation Bar Home Current Issue Past Issues Skin Diseases Cross-section of human skin Past Issues / Fall 2008 Table of Contents For ... Logical Images, Inc. I n the areas of skin health and skin diseases, the NIH's National Institute ...

  19. Glutathione dysregulation and the etiology and progression of human diseases.

    NARCIS (Netherlands)

    Ballatori, N.; Krance, S.M.; Notenboom, S.; Shi, S.; Tieu, K.; Hammond, C.L.

    2009-01-01

    Glutathione (GSH) plays an important role in a multitude of cellular processes, including cell differentiation, proliferation, and apoptosis, and as a result, disturbances in GSH homeostasis are implicated in the etiology and/or progression of a number of human diseases, including cancer, diseases

  20. Mosquitoes as vectors of human disease in South Africa | Jupp ...

    African Journals Online (AJOL)

    While malaria is the most important mosquito-borne disease in South Africa, there are also several mosquito-borne viruses that also cause human disease. The most significant are chikungunya, West Nile, Sindbis and Rift Valley fever viruses. In this review these are compared with malaria, mainly in regard to their ecology ...

  1. A murine model of human myeloma bone disease

    NARCIS (Netherlands)

    Garrett, I.R.; Dallas, S.; Radl, J.; Mundy, G.R.

    1997-01-01

    Myeloma causes a devastating and unique form of osteolytic bone disease. Although osteoclast activation is responsible for bone destruction, the precise mechanisms by which myeloma cells increase osteoclast activity have not been defined. An animal model of human myeloma bone disease mould help in

  2. Animal models of human respiratory syncytial virus disease

    NARCIS (Netherlands)

    Bem, Reinout A.; Domachowske, Joseph B.; Rosenberg, Helene F.

    2011-01-01

    Infection with the human pneumovirus pathogen, respiratory syncytial virus (hRSV), causes a wide spectrum of respiratory disease, notably among infants and the elderly. Laboratory animal studies permit detailed experimental modeling of hRSV disease and are therefore indispensable in the search for

  3. The DNA-damage response in human biology and disease

    DEFF Research Database (Denmark)

    Jackson, Stephen P; Bartek, Jiri

    2009-01-01

    , signal its presence and mediate its repair. Such responses, which have an impact on a wide range of cellular events, are biologically significant because they prevent diverse human diseases. Our improving understanding of DNA-damage responses is providing new avenues for disease management....

  4. Genetic characterization of the partial mitochondrial cytochrome oxidase c subunit I (cox 1) gene of the zoonotic parasitic nematode, Ancylostoma ceylanicum from humans, dogs and cats.

    Science.gov (United States)

    Ngui, Romano; Mahdy, Mohammed A K; Chua, Kek Heng; Traub, Rebecca; Lim, Yvonne A L

    2013-10-01

    Ancylostoma ceylanicum is the only zoonotic hookworm species that is able to produce patent infections in humans with the majority of cases reported in South East Asia. Over the past few years, there have been an increasing number of studies investigating the prevalence of this parasitic zoonosis using molecular diagnostic tools and a single genetic locus as marker for species identification. As there can be limitations in using a single genetic locus for epidemiological studies and genetic discrimination, the complementary use of a more variable locus will provide additional evidence to support the zoonotic exchange of hookworm species between humans and animals. In the present study, the cytochrome c oxidase subunit 1 (cox 1) sequence of A. ceylanicum from positive human and animal fecal samples were determined and compared with published reference sequences. Phylogenetic analysis demonstrated that isolates of A. ceylanicum were divided into two clusters, one consisting 3 human isolates and the other comprising 19 isolates of human and animal origin from different geographical locations within Malaysia. The two groups of A. ceylanicum could be distinguished from one another through five fixed nucleotide differences at locations 891, 966, 1008, 1077 and 1083. The detection of genetically distinct groups and considerable level of genetic variation within the cox 1 sequence of A. ceylanicum might suggest potential haplotype-linked differences in zoonotic, epidemiological and pathobiological characteristics, a hypothesis that still needs further investigation. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Positions of human dwellings affect few tropical diseases near ...

    African Journals Online (AJOL)

    user

    Some factors that possibly affect tropical disease distribution was investigated in about 500 randomize human dwellings. The studied factors include wild animals, domestic animals, wild plants, cultivated plants, nature of soil, nature of water, positions of human dwellings, nature of building material and position of animal ...

  6. Animal models for human genetic diseases | Sharif | African Journal ...

    African Journals Online (AJOL)

    The study of human genetic diseases can be greatly aided by animal models because of their similarity to humans in terms of genetics. In addition to understand diverse aspects of basic biology, model organisms are extensively used in applied research in agriculture, industry, and also in medicine, where they are used to ...

  7. Multifractal Detrended Fluctuation Analysis of Human gait Diseases

    Directory of Open Access Journals (Sweden)

    Srimonti eDutta

    2013-10-01

    Full Text Available IIn this paper multifractal detrended fluctuation analysis is used to study the human gait time series for normal and diseased sets. It is observed that long range correlation is primarily responsible for the origin of multifractality. The study reveals that the degree of multifractality is more for normal set compared to diseased set. However the method fails to distinguish between the two diseased sets.

  8. DEGAS: de novo discovery of dysregulated pathways in human diseases.

    Directory of Open Access Journals (Sweden)

    Igor Ulitsky

    Full Text Available BACKGROUND: Molecular studies of the human disease transcriptome typically involve a search for genes whose expression is significantly dysregulated in sick individuals compared to healthy controls. Recent studies have found that only a small number of the genes in human disease-related pathways show consistent dysregulation in sick individuals. However, those studies found that some pathway genes are affected in most sick individuals, but genes can differ among individuals. While a pathway is usually defined as a set of genes known to share a specific function, pathway boundaries are frequently difficult to assign, and methods that rely on such definition cannot discover novel pathways. Protein interaction networks can potentially be used to overcome these problems. METHODOLOGY/PRINCIPAL FINDINGS: We present DEGAS (DysrEgulated Gene set Analysis via Subnetworks, a method for identifying connected gene subnetworks significantly enriched for genes that are dysregulated in specimens of a disease. We applied DEGAS to seven human diseases and obtained statistically significant results that appear to home in on compact pathways enriched with hallmarks of the diseases. In Parkinson's disease, we provide novel evidence for involvement of mRNA splicing, cell proliferation, and the 14-3-3 complex in the disease progression. DEGAS is available as part of the MATISSE software package (http://acgt.cs.tau.ac.il/matisse. CONCLUSIONS/SIGNIFICANCE: The subnetworks identified by DEGAS can provide a signature of the disease potentially useful for diagnosis, pinpoint possible pathways affected by the disease, and suggest targets for drug intervention.

  9. Are adequate methods available to detect protist parasites on fresh produce?

    Science.gov (United States)

    Human parasitic protists such as Cryptosporidium, Giardia and microsporidia contaminate a variety of fresh produce worldwide. Existing detection methods lack sensitivity and specificity for most foodborne parasites. Furthermore, detection has been problematic because these parasites adhere tenacious...

  10. A proposition on the genetic history of visceral Leishmaniasis:glimpses from the side of parasite

    International Nuclear Information System (INIS)

    Ibrahim, Muntasir E.

    1999-01-01

    The recorded history of diseases affecting man, contains hardly any reliable information on their state beyond few centuries ago. This is particularly true for diseases having symptoms common to others as is typically the case of visceral Leishmaniasis. Our increased understanding of the biology and epidemiology of VL during the last hundred years or so, nevertheless, raise more questions than answers. For example: what is the possible role played by such disease in shaping the population structure and range of expaion of their human host. Could resistance of certain populations to disease be explained by the distribution of less virulent parasite strains e.g. (Leishmania infantum) or by ancient episodes of strong selection? data obtained from molecular analysis of parasites isolated from patients in Sudan, indicates that the current outbreak is probably a recent event caused by stocks of closely related parasites. More recently, mitochondrial hapoltypes analysis gave further support to the homogeneity of these parasite populations. Cladistic analysis of Leishmania donovani strains from different continents make a clear distinction between two clades; one containing parasites of the infantum group in different continents and the other includes members of the donovani group in Africa and Asia. Furthermore, we did not encounter-a-presence-of Leishmania infantum specific sequence within paraite population sampled in the areas, covered by the outbreaks. The parasites from Sudan presented with the most ancestral haplotypes. The disease in Sudan may have passed through short periods of protraction and expansion, which may have resulted in stability of the parasite genetic population structure, but rather a fragile host-parasite relationship. Studying host sequence may reveal equally interesting situations and shed more light on these-aspects.(Author)

  11. Genome content analysis yields new insights into the relationship between the human malaria parasite Plasmodium falciparum and its anopheline vectors.

    Science.gov (United States)

    Oppenheim, Sara J; Rosenfeld, Jeffrey A; DeSalle, Rob

    2017-02-27

    The persistent and growing gap between the availability of sequenced genomes and the ability to assign functions to sequenced genes led us to explore ways to maximize the information content of automated annotation for studies of anopheline mosquitos. Specifically, we use genome content analysis of a large number of previously sequenced anopheline mosquitos to follow the loss and gain of protein families over the evolutionary history of this group. The importance of this endeavor lies in the potential for comparative genomic studies between Anopheles and closely related non-vector species to reveal ancestral genome content dynamics involved in vector competence. In addition, comparisons within Anopheles could identify genome content changes responsible for variation in the vectorial capacity of this family of important parasite vectors. The competence and capacity of P. falciparum vectors do not appear to be phylogenetically constrained within the Anophelinae. Instead, using ancestral reconstruction methods, we suggest that a previously unexamined component of vector biology, anopheline nucleotide metabolism, may contribute to the unique status of anophelines as P. falciparum vectors. While the fitness effects of nucleotide co-option by P. falciparum parasites on their anopheline hosts are not yet known, our results suggest that anopheline genome content may be responding to selection pressure from P. falciparum. Whether this response is defensive, in an attempt to redress improper nucleotide balance resulting from P. falciparum infection, or perhaps symbiotic, resulting from an as-yet-unknown mutualism between anophelines and P. falciparum, is an open question that deserves further study. Clearly, there is a wealth of functional information to be gained from detailed manual genome annotation, yet the rapid increase in the number of available sequences means that most researchers will not have the time or resources to manually annotate all the sequence data they

  12. Deep-sequencing to resolve complex diversity of apicomplexan parasites in platypuses and echidnas: Proof of principle for wildlife disease investigation.

    Science.gov (United States)

    Šlapeta, Jan; Saverimuttu, Stefan; Vogelnest, Larry; Sangster, Cheryl; Hulst, Frances; Rose, Karrie; Thompson, Paul; Whittington, Richard

    2017-11-01

    The short-beaked echidna (Tachyglossus aculeatus) and the platypus (Ornithorhynchus anatinus) are iconic egg-laying monotremes (Mammalia: Monotremata) from Australasia. The aim of this study was to demonstrate the utility of diversity profiles in disease investigations of monotremes. Using small subunit (18S) rDNA amplicon deep-sequencing we demonstrated the presence of apicomplexan parasites and confirmed by direct and cloned amplicon gene sequencing Theileria ornithorhynchi, Theileria tachyglossi, Eimeria echidnae and Cryptosporidium fayeri. Using a combination of samples from healthy and diseased animals, we show a close evolutionary relationship between species of coccidia (Eimeria) and piroplasms (Theileria) from the echidna and platypus. The presence of E. echidnae was demonstrated in faeces and tissues affected by disseminated coccidiosis. Moreover, the presence of E. echidnae DNA in the blood of echidnas was associated with atoxoplasma-like stages in white blood cells, suggesting Hepatozoon tachyglossi blood stages are disseminated E. echidnae stages. These next-generation DNA sequencing technologies are suited to material and organisms that have not been previously characterised and for which the material is scarce. The deep sequencing approach supports traditional diagnostic methods, including microscopy, clinical pathology and histopathology, to better define the status quo. This approach is particularly suitable for wildlife disease investigation. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. [Bartonellosis. II. Other Bartonella responsible for human diseases].

    Science.gov (United States)

    Piémont, Y; Heller, R

    1999-01-01

    In addition to Bartonella henselae, five other Bartonella species were involved in human pathology. As for B. henselae, ectoparasites seem to be responsible for the transmission of most or all these bacterial species. B. bacilliformis is responsible for Carrion's disease that occurs in some valleys of Colombia, Ecuador and Peru. This disease is transmitted by biting of infected sandflies. The bacterial reservoir is constituted by humans only. That disease occurs either as an acute form with severe infectious hemolytic anemia (or Oroya fever), or as benign cutaneous tumors, also called verruga peruana. Healthy blood carriers of the bacterium exist. Trench fever was described during the First World War. This non-lethal disease is constituted of recurrent febrile attacks associated particularly with osseous pains. The causative agent of the disease is B. quintana, transmitted by the body louse. Humans seem to be the reservoir of that bacterium. In some patients, B. quintana can be responsible for endocarditis, bacillary angiomatosis and chronic or recurrent bacteremia. Other human infections due to Bartonella sp. have been described: B. vinsonii, isolated from blood of small rodents, and B. elizabethae, the reservoir of which is currently unknown, can be responsible for endocardites. B. clarridgeiae (isolated from blood of 5% of pet cats and 17% of stray cats) may be responsible for human cat scratch disease. All these bartonelloses are diagnosed by non-standard blood culture or by in vitro DNA amplification or by serological testing. Their treatment requires tetracyclines or chloramphenicol or macrolides.

  14. Impacts of Gut Bacteria on Human Health and Diseases

    Science.gov (United States)

    Zhang, Yu-Jie; Li, Sha; Gan, Ren-You; Zhou, Tong; Xu, Dong-Ping; Li, Hua-Bin

    2015-01-01

    Gut bacteria are an important component of the microbiota ecosystem in the human gut, which is colonized by 1014 microbes, ten times more than the human cells. Gut bacteria play an important role in human health, such as supplying essential nutrients, synthesizing vitamin K, aiding in the digestion of cellulose, and promoting angiogenesis and enteric nerve function. However, they can also be potentially harmful due to the change of their composition when the gut ecosystem undergoes abnormal changes in the light of the use of antibiotics, illness, stress, aging, bad dietary habits, and lifestyle. Dysbiosis of the gut bacteria communities can cause many chronic diseases, such as inflammatory bowel disease, obesity, cancer, and autism. This review summarizes and discusses the roles and potential mechanisms of gut bacteria in human health and diseases. PMID:25849657

  15. The fish parasite Ichthyophthirius multifiliis

    DEFF Research Database (Denmark)

    Jørgensen, Louise von Gersdorff

    2017-01-01

    Ichthyophthirius multifiliis, the causative agent of white spot disease (ichthyophthiriasis) is a major burden for fish farmers and aquarists globally. The parasite infects the skin and the gills of freshwater fish, which may acquire a protective adaptive immune response against this disease...... and recognition of carcinogenic and environmentally damaging effects the most efficient compounds are prohibited. A continuous search for novel substances, which are highly effective against the parasites and harmless for the fish is ongoing. These compounds should be environmentally friendly and cost...

  16. Wildlife disease prevalence in human-modified landscapes.

    Science.gov (United States)

    Brearley, Grant; Rhodes, Jonathan; Bradley, Adrian; Baxter, Greg; Seabrook, Leonie; Lunney, Daniel; Liu, Yan; McAlpine, Clive

    2013-05-01

    Human-induced landscape change associated with habitat loss and fragmentation places wildlife populations at risk. One issue in these landscapes is a change in the prevalence of disease which may result in increased mortality and reduced fecundity. Our understanding of the influence of habitat loss and fragmentation on the prevalence of wildlife diseases is still in its infancy. What is evident is that changes in disease prevalence as a result of human-induced landscape modification are highly variable. The importance of infectious diseases for the conservation of wildlife will increase as the amount and quality of suitable habitat decreases due to human land-use pressures. We review the experimental and observational literature of the influence of human-induced landscape change on wildlife disease prevalence, and discuss disease transmission types and host responses as mechanisms that are likely to determine the extent of change in disease prevalence. It is likely that transmission dynamics will be the key process in determining a pathogen's impact on a host population, while the host response may ultimately determine the extent of disease prevalence. Finally, we conceptualize mechanisms and identify future research directions to increase our understanding of the relationship between human-modified landscapes and wildlife disease prevalence. This review highlights that there are rarely consistent relationships between wildlife diseases and human-modified landscapes. In addition, variation is evident between transmission types and landscape types, with the greatest positive influence on disease prevalence being in urban landscapes and directly transmitted disease systems. While we have a limited understanding of the potential influence of habitat loss and fragmentation on wildlife disease, there are a number of important areas to address in future research, particularly to account for the variability in increased and decreased disease prevalence. Previous studies

  17. Intestinal parasites and genotyping of Giardia duodenalis in children: first report of genotype B in isolates from human clinical samples in Mexico

    Directory of Open Access Journals (Sweden)

    Julio César Torres-Romero

    2014-06-01

    Full Text Available Giardia duodenalis is one of the most prevalent enteroparasites in children. This parasite produces several clinical manifestations. The aim of this study was to determine the prevalence of genotypes of G. duodenalis causing infection in a region of southeastern Mexico. G. duodenalis cysts were isolated (33/429 from stool samples of children and molecular genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP analysis, targeting the triosephosphate isomerase ( tpi and glutamate dehydrogenase ( gdh genes. The tpi gene was amplified in all of the cyst samples, either for assemblage A (27 samples or assemblage B (6 samples. RFLP analysis classified the 27 tpi -A amplicons in assemblage A, subgenotype I. Samples classified as assemblage B were further analysed using PCR-RFLP of the gdh gene and identified as assemblage B, subgenotype III. To our knowledge, this is the first report of assemblage B of G. duodenalis in human clinical samples from Mexico.

  18. Host-parasite interaction: selective Pv-fam-a family proteins of Plasmodium vivax bind to a restricted number of human erythrocyte receptors.

    Science.gov (United States)

    Zeeshan, Mohammad; Tyagi, Rupesh Kumar; Tyagi, Kriti; Alam, Mohd Shoeb; Sharma, Yagya Dutta

    2015-04-01

    Plasmodium vivax synthesizes the largest number of 36 tryptophan-rich proteins belonging to the Pv-fam-a family. These parasite proteins need to be characterized for their biological function because tryptophan-rich proteins from other Plasmodium species have been proposed as vaccine candidates. Recombinant P. vivax tryptophan-rich antigens (PvTRAgs) were used to determine their erythrocyte-binding activity by a cell-based enzyme-linked immunosorbent assay, flow cytometry, and a rosetting assay. Only 4 (PvTRAg26.3, PvTRAg34, PvTRAg36, and PvTRAg36.6) of 21 PvTRAgs bind to host erythrocytes. The cross-competition data indicated that PvTRAg36 and PvTRAg34 share their erythrocyte receptors with previously described proteins PvTRAg38 and PvTRAg33.5, respectively. On the other hand, PvTRAg26.3 and PvTRAg36.6 cross-compete with each other and not with any other PvTRAg, indicating that these 2 proteins bind to the same but yet another set of erythrocyte receptor(s). Together, 10 of 36 PvTRAgs possess erythrocyte-binding activity in which each protein recognizes >1 erythrocyte receptor. Further, each erythrocyte receptor is shared by >1 PvTRAg. This redundancy may be useful for the parasite to invade red blood cells and cause disease pathogenesis, and it can be exploited to develop therapeutics against P. vivax malaria. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  19. Parasites and cancers: parasite antigens as possible targets for cancer immunotherapy.

    Science.gov (United States)

    Darani, Hossein Yousofi; Yousefi, Morteza

    2012-12-01

    An adverse relationship between some parasite infections and cancer in the human population has been reported by different research groups. Anticancer activity of some parasites such as Trypanosoma cruzi, Toxoplasma gondii, Toxocara canis, Acantamoeba castellani and Plasmodium yoelii has been shown in experimental animals. Moreover, it has been shown that cancer-associated mucin-type O-glycan compositions are made by parasites, therefore cancers and parasites have common antigens. In this report anticancer activities of some parasites have been reviewed and the possible mechanisms of these actions have also been discussed.

  20. A research agenda for helminth diseases of humans: health research and capacity building in disease-endemic countries for helminthiases control.

    Directory of Open Access Journals (Sweden)

    Mike Y Osei-Atweneboana

    Full Text Available Capacity building in health research generally, and helminthiasis research particularly, is pivotal to the implementation of the research and development agenda for the control and elimination of human helminthiases that has been proposed thematically in the preceding reviews of this collection. Since helminth infections affect human populations particularly in marginalised and low-income regions of the world, they belong to the group of poverty-related infectious diseases, and their alleviation through research, policy, and practice is a sine qua non condition for the achievement of the United Nations Millennium Development Goals. Current efforts supporting research capacity building specifically for the control of helminthiases have been devised and funded, almost in their entirety, by international donor agencies, major funding bodies, and academic institutions from the developed world, contributing to the creation of (not always equitable North-South "partnerships". There is an urgent need to shift this paradigm in disease-endemic countries (DECs by refocusing political will, and harnessing unshakeable commitment by the countries' governments, towards health research and capacity building policies to ensure long-term investment in combating and sustaining the control and eventual elimination of infectious diseases of poverty. The Disease Reference Group on Helminth Infections (DRG4, established in 2009 by the Special Programme for Research and Training in Tropical Diseases (TDR, was given the mandate to review helminthiases research and identify research priorities and gaps. This paper discusses the challenges confronting capacity building for parasitic disease research in DECs, describes current capacity building strategies with particular reference to neglected tropical diseases and human helminthiases, and outlines recommendations to redress the balance of alliances and partnerships for health research between the developed countries of

  1. An ethical and prudential argument for prioritizing the reduction of parasite-stress in the allocation of health care resources.

    Science.gov (United States)

    Powell, Russell; Clarke, Steve; Savulescu, Julian

    2012-04-01

    The link between parasite-stress and complex psychological dispositions implies that the social, political, and economic benefits likely to flow from public health interventions that reduce rates of non-zoonotic infectious disease are far greater than have traditionally been thought. We sketch a prudential and ethical argument for increasing public health resources globally and redistributing these to focus on the alleviation of parasite-stress in human populations.

  2. FISH CONSUMPTION, METHYLMERCURY, AND HUMAN HEART DISEASE.

    Energy Technology Data Exchange (ETDEWEB)

    LIPFERT, F.W.; SULLIVAN, T.M.

    2005-09-21

    Environmental mercury continues to be of concern to public health advocates, both in the U.S. and abroad, and new research continues to be published. A recent analysis of potential health benefits of reduced mercury emissions has opened a new area of public health concern: adverse effects on the cardiovascular system, which could account for the bulk of the potential economic benefits. The authors were careful to include caveats about the uncertainties of such impacts, but they cited only a fraction of the applicable health effects literature. That literature includes studies of the potentially harmful ingredient (methylmercury, MeHg) in fish, as well as of a beneficial ingredient, omega-3 fatty acids or ''fish oils''. The U.S. Food and Drug Administration (FDA) recently certified that some of these fat compounds that are primarily found in fish ''may be beneficial in reducing coronary heart disease''. This paper briefly summarizes and categorizes the extensive literature on both adverse and beneficial links between fish consumption and cardiovascular health, which are typically based on studies of selected groups of individuals (cohorts). Such studies tend to comprise the ''gold standard'' of epidemiology, but cohorts tend to exhibit a great deal of variability, in part because of the limited numbers of individuals involved and in part because of interactions with other dietary and lifestyle considerations. Note that eating fish will involve exposure to both the beneficial effects of fatty acids and the potentially harmful effects of contaminants like Hg or PCBs, all of which depend on the type of fish but tend to be correlated within a population. As a group, the cohort studies show that eating fish tends to reduce mortality, especially due to heart disease, for consumption rates up to about twice weekly, above which the benefits tend to level off. A Finnish cohort study showed increased mortality risks

  3. Human genomic disease variants: a neutral evolutionary explanation.

    Science.gov (United States)

    Dudley, Joel T; Kim, Yuseob; Liu, Li; Markov, Glenn J; Gerold, Kristyn; Chen, Rong; Butte, Atul J; Kumar, Sudhir

    2012-08-01

    Many perspectives on the role of evolution in human health include nonempirical assumptions concerning the adaptive evolutionary origins of human diseases. Evolutionary analyses of the increasing wealth of clinical and population genomic data have begun to challenge these presumptions. In order to systematically evaluate such claims, the time has come to build a common framework for an empirical and intellectual unification of evolution and modern medicine. We review the emerging evidence and provide a supporting conceptual framework that establishes the classical neutral theory of molecular evolution (NTME) as the basis for evaluating disease- associated genomic variations in health and medicine. For over a decade, the NTME has already explained the origins and distribution of variants implicated in diseases and has illuminated the power of evolutionary thinking in genomic medicine. We suggest that a majority of disease variants in modern populations will have neutral evolutionary origins (previously neutral), with a relatively smaller fraction exhibiting adaptive evolutionary origins (previously adaptive). This pattern is expected to hold true for common as well as rare disease variants. Ultimately, a neutral evolutionary perspective will provide medicine with an informative and actionable framework that enables objective clinical assessment beyond convenient tendencies to invoke past adaptive events in human history as a root cause of human disease.

  4. How Many Parasites Species a Frog Might Have? Determinants of Parasite Diversity in South American Anurans.

    Directory of Open Access Journals (Sweden)

    Karla Magalhães Campião

    Full Text Available There is an increasing interest in unveiling the dynamics of parasite infection. Understanding the interaction patterns, and determinants of host-parasite association contributes to filling knowledge gaps in both community and disease ecology. Despite being targeted as a relevant group for conservation efforts, determinants of the association of amphibians and their parasites in broad scales are poorly understood. Here we describe parasite biodiversity in South American amphibians, testing the influence of host body size and geographic range in helminth parasites species richness (PSR. We also test whether parasite diversity is related to hosts' phylogenetic diversity. Results showed that nematodes are the most common anuran parasites. Host-parasite network has a nested pattern, with specialist helminth taxa generally associated with hosts that harbour the richest parasite faunas. Host size is positively correlated with helminth fauna richness, but we found no support for the association of host geographic range and PSR. These results remained consistent after correcting for uneven study effort and hosts' phylogenic correlation. However, we found no association between host and parasite diversity, indicating that more diversified anuran clades not necessarily support higher parasite diversity. Overall, considering both the structure and the determinants of PRS in anurans, we conclude that specialist parasites are more likely to be associated with large anurans, which are the ones harbouring higher PSR, and that the lack of association of PSR with hosts' clade diversification suggests it is strongly influenced by ecological and contemporary constrains.

  5. Drosophila tools and assays for the study of human diseases

    Directory of Open Access Journals (Sweden)

    Berrak Ugur

    2016-03-01

    Full Text Available Many of the internal organ systems of Drosophila melanogaster are functionally analogous to those in vertebrates, including humans. Although humans and flies differ greatly in terms of their gross morphological and cellular features, many of the molecular mechanisms that govern development and drive cellular and physiological processes are conserved between both organisms. The morphological differences are deceiving and have led researchers to undervalue the study of invertebrate organs in unraveling pathogenic mechanisms of diseases. In this review and accompanying poster, we highlight the physiological and molecular parallels between fly and human organs that validate the use of Drosophila to study the molecular pathogenesis underlying human diseases. We discuss assays that have been developed in flies to study the function of specific genes in the central nervous system, heart, liver and kidney, and provide examples of the use of these assays to address questions related to human diseases. These assays provide us with simple yet powerful tools to study the pathogenic mechanisms associated with human disease-causing genes.

  6. Echinococcosis and other parasitic infections in domestic dogs from urban areas of an argentinean Patagonian city

    OpenAIRE

    Flores, Verónica; Viozzi, Gustavo; Garibotti, Gilda; Zacharias, Daniela; Debiaggi, María Florencia; Kabaradjian, Surpik

    2017-01-01

    In urban populations of South America, dogs with free access to public areas represent a public health concern. The primary consequence of roaming dogs on human health is the transmission of infectious and parasitic diseases mainly through feces contamination. The main diseases likely to be transmitted are hydatidosis or echinococcosis, larva migrans, and giardiasis. In Argentina, hydatidosis ranks among the most prevalent zoonosis. Although it is considered a rural disease, the circulation o...

  7. Polycystins, calcium signaling, and human diseases

    International Nuclear Information System (INIS)

    Delmas, Patrick; Padilla, Francoise; Osorio, Nancy; Coste, Bertrand; Raoux, Matthieu; Crest, Marcel

    2004-01-01

    Autosomal dominant polycystic kidney disease (ADPKD) is a major, inherited nephropathy affecting over 1:1000 of the worldwide population. It is a systemic condition with frequent hepatic and cardiovascular manifestations in addition to the progressive development of fluid-filled cysts from the tubules and collecting ducts of affected kidneys. The pathogenesis of cyst formation is currently thought to involve increased proliferation of epithelial cells, mild dedifferentiation, and fluid accumulation. In the past decade, study of ADPKD led to the discovery of a unique family of highly complex proteins, the polycystins. Loss-of-function mutations in either of two polycystin proteins, polycystin-1 or polycystin-2, give rise to ADPKD. These proteins are thought to function together as part of a multiprotein complex that may initiate Ca 2+ signals, directing attention to the regulation of intracellular Ca 2+ as a possible misstep that participates in cyst formation. Here we review what is known about the Ca 2+ signaling functions of polycystin proteins and focus on findings that have significantly advanced our physiological insight. Special attention is paid to the recently discovered role of these proteins in the mechanotransduction of the renal primary cilium and the model it suggests

  8. Rare human diseases: 9p deletion syndrome

    Directory of Open Access Journals (Sweden)

    Galagan V.O.

    2014-09-01

    Full Text Available Objective of the study was to review the anamnesis, pheno - and genotype in patients with rare chromosome disorders such as 9p deletion syndrome. Genetic methods of investigation (clinical and genealogical, cytogenetic, FISH- method, paraclinical and instrumental methods of examination were used. Karyotyping was performed by the G-method of differential staining of chromosomes. Only three cases of pathology were diagnosed in the Medical Genetics Center over the last 10 years. By anamnesis data nobody in the probands’ families had bad habits, was exposed to occupational hazards, took part in the elimination of the Chernobyl accident or lived in contaminated areas. Clinical signs of diseases have not been identified in probands’ parents. All probands had trigonocephaly, bilateral epicanthal folds, ocular hypertelorism, downslanting palpebral fissures, long philtrum, flat face and nasal bridge, low set ears with malformed auricles. Two patients of three ones had exophthalmos, contracture of the second and third fingers, abnormal external genitalia. In all three cases there was monosomy of chromosome 9 of critical segment p 24. Normal karyotypes were seen in all parents, so there were three cases of new mutations of 9p deletion syndrome. Retardation of physical, psycho-spech, mental development in proband with or without congenital anomalies requires medical genetic counseling in a specialized institution. Cases of reproductive loss in anamnesis require cytogenetic investigation of fetal membranes and amniotic fluid.

  9. Parasite diversity of disease-bearing rodents of Southeast Asia: habitat determinants and effects on sexual size dimorphism and life-traits

    Directory of Open Access Journals (Sweden)

    Serge eMorand

    2015-10-01

    Full Text Available We investigated a causal chain of relationships between habitat specialization and parasite species richness in rodent communities in Southeast Asia, and the consequences for variation in immune investment (using spleen size, the degree of sexual competition (using testes and sexual size dimorphism (SSD. We used data gathered on rodents, their habitat specialization and their parasites (macro- and micro-parasites in Southeast Asian landscapes. The results supported the hypotheses that parasite diversity drives the evolution of host life-traits and sexual selection. Firstly host habitat specialization explained the variation in parasite species richness. Secondly high parasite species richness was linked to host immune investment, using the relative spleen size of rodents. Thirdly according to the potential costs associated with immune investment, the relative spleen size was found to be negatively correlated with the relative size of testes among rodents. Fourthly, a positive relationship between male-biased SSD and parasite species richness was observed supporting the role of parasitism in sexual selection. Finally, the variation in SSD was positively associated with the degree of habitat specialization. Highest values of female-biased SSD were associated with habitat specialization, whereas highest values of male-biased SSD concerned synanthropic or generalist rodent species. These results, also correlative, will help to facilitate selection of the species that should be thoroughly investigated at the population level to better understand the selective effects of parasites on rodent life-history and behavior.

  10. Infectious prion diseases in humans: cannibalism, iatrogenicity and zoonoses.

    Science.gov (United States)

    Haïk, Stéphane; Brandel, Jean-Philippe

    2014-08-01

    In contrast with other neurodegenerative disorders associated to protein misfolding, human prion diseases include infectious forms (also called transmitted forms) such as kuru, iatrogenic Creutzfeldt-Jakob disease and variant Creutzfeldt-Jakob disease. The transmissible agent is thought to be solely composed of the abnormal isoform (PrP(Sc)) of the host-encoded prion protein that accumulated in the central nervous system of affected individuals. Compared to its normal counterpart, PrP(Sc) is β-sheet enriched and aggregated and its propagation is based on an autocatalytic conversion process. Increasing evidence supports the view that conformational variations of PrP(Sc) encoded the biological properties of the various prion strains that have been isolated by transmission studies in experimental models. Infectious forms of human prion diseases played a pivotal role in the emergence of the prion concept and in the characterization of the very unconventional properties of prions. They provide a unique model to understand how prion strains are selected and propagate in humans. Here, we review and discuss how genetic factors interplay with strain properties and route of transmission to influence disease susceptibility, incubation period and phenotypic expression in the light of the kuru epidemics