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Journal of Applied Microbiology 2004The application of the AC electrokinetic technique of electrorotation for studying eukaryotic parasite transmission stages is reviewed. Electrorotation is a noninvasive... (Review)
Review
AIMS
The application of the AC electrokinetic technique of electrorotation for studying eukaryotic parasite transmission stages is reviewed. Electrorotation is a noninvasive technique that utilizes electrically energized microelectrode structures within micro-fluidic chambers to probe the physiological structure of micro-organisms. Application of the technique to the transmission life cycle stages of three separate genera of protozoan parasites, Cryptosporidium, Giardia and Cyclospora, and one nematode genus Ascaris, each of significant public health importance, is described.
METHODS AND RESULTS
Standard electrorotation apparatus, consisting of micro-fabricated electrodes in a fluidic chip, quadrature sinusoidal signal generator, microscope and image capture system, was used to study each organism. Spectra of cellular rotation rate were recorded as a function of applied electric field frequency and compared with standardized biological tests, where appropriate, to illustrate the effectiveness and versatility of the electrorotation technique.
CONCLUSIONS
Electrorotational determination of the viability of individual G. intestinalis cysts, Cryptosporidium parvum and Cyclospora cayetanensis oocysts has been achieved. The sporulation state of Cyclospora cayetanensis oocysts was also readily determined, as was the fertilization state of A. suum ova.
SIGNIFICANCE AND IMPACT OF THE STUDY
Electrorotation is a simple, noninvasive and versatile analytical technique suited to a wide range of particle types and capable of incorporation into integrated Lab-on-a-chip devices.
Topics: Animals; Cryptosporidium; Cyclospora; Electromagnetic Fields; Giardia; Microelectrodes; Miniaturization; Parasites; Parasitology; Rotation
PubMed: 14678156
DOI: 10.1046/j.1365-2672.2003.02113.x -
PLoS Neglected Tropical Diseases Jan 2017This survey investigated the distribution of various intestinal parasites and vector-borne pathogens in stray and free-roaming cats living in four regions of Greece. A...
This survey investigated the distribution of various intestinal parasites and vector-borne pathogens in stray and free-roaming cats living in four regions of Greece. A total number of one hundred and fifty cats living in three Islands (Crete, Mykonos and Skopelos) and in Athens municipality was established as a realistic aim to be accomplished in the study areas. All cats were examined with different microscopic, serological and molecular assays aiming at evaluating the occurrence of intestinal parasites, and exposure to or presence of vector-borne infections. A total of 135 cats (90%) was positive for one or more parasites and/or pathogens transmitted by ectoparasites. Forty-four (29.3%) cats were positive for one single infection, while 91 (60.7%) for more than one pathogen. A high number of (n. 53) multiple infections caused by feline intestinal and vector-borne agents including at least one zoonotic pathogen was detected. Among them, the most frequently recorded helminths were roundworms (Toxocara cati, 24%) and Dipylidium caninum (2%), while a high number of examined animals (58.8%) had seroreaction for Bartonella spp., followed by Rickettsia spp. (43.2%) and Leishmania infantum (6.1%). DNA-based assays revealed the zoonotic arthropod-borne organisms Bartonella henselae, Bartonella clarridgeiae, Rickettsia spp., and L. infantum. These results show that free-ranging cats living in areas of Greece under examination may be exposed to a plethora of internal parasites and vector-borne pathogens, some of them potentially able to infect humans. Therefore, epidemiological vigilance and appropriate control measures are crucial for the prevention and control of these infections and to minimize the risk of infection for people.
Topics: Animals; Cat Diseases; Cats; Female; Greece; Intestinal Diseases, Parasitic; Male; Parasites
PubMed: 28141857
DOI: 10.1371/journal.pntd.0005335 -
Parasitology Feb 2015
Topics: Animals; Biological Evolution; Genome; Humans; Parasites; Parasitic Diseases
PubMed: 25656359
DOI: 10.1017/S0031182014001516 -
Parasitology Feb 2015SUMMARY From hundreds of independent transitions from a free-living existence to a parasitic mode of life, separate parasite lineages have converged over evolutionary... (Review)
Review
SUMMARY From hundreds of independent transitions from a free-living existence to a parasitic mode of life, separate parasite lineages have converged over evolutionary time to share traits and exploit their hosts in similar ways. Here, we first summarize the evidence that, at a phenotypic level, eukaryotic parasite lineages have all converged toward only six general parasitic strategies: parasitoid, parasitic castrator, directly transmitted parasite, trophically transmitted parasite, vector-transmitted parasite or micropredator. We argue that these strategies represent adaptive peaks, with the similarities among unrelated taxa within any strategy extending to all basic aspects of host exploitation and transmission among hosts and transcending phylogenetic boundaries. Then, we extend our examination of convergent patterns by looking at the evolution of parasite genomes. Despite the limited taxonomic coverage of sequenced parasite genomes currently available, we find some evidence of parallel evolution among unrelated parasite taxa with respect to genome reduction or compaction, and gene losses or gains. Matching such changes in parasite genomes with the broad phenotypic traits that define the convergence of parasites toward only six strategies of host exploitation is not possible at present. Nevertheless, as more parasite genomes become available, we may be able to detect clear trends in the evolution of parasitic genome architectures representing true convergent adaptive peaks, the genomic equivalents of the phenotypic strategies used by all parasites.
Topics: Animals; Biological Evolution; Ecology; Genomics; Host-Parasite Interactions; Parasites; Phylogeny
PubMed: 24229807
DOI: 10.1017/S0031182013001674 -
Annals of Agricultural and... Dec 2019Over 300 species of parasites can possibly be passed on humans. Most of the parasitic infections are defined based on their pathogenicity; however, some positive effects... (Review)
Review
INTRODUCTION
Over 300 species of parasites can possibly be passed on humans. Most of the parasitic infections are defined based on their pathogenicity; however, some positive effects of a parasite existence within the human body have recently been suggested. Beneficial outcomes of parasite infections might result from the production and release of metabolites, modification of host immune response or products uptake of the host.
OBJECTIVE
The aim of the study was a comprehensive analysis of a wide range of effects of parasites on the human body, including an overview of the toxic and positive effects.
STATE OF KNOWLEDGE
In the light of the latest research presenting the unconventional use of parasites in medicine, the widely understood of their impact on the human body can also be considered in a positive context. Clinical cases from diseases caused by the toxic effects of parasites, as described in recent years, indicate that the problem of parasitic infections still persists. Despite a great deal of knowledge about the toxic effects of parasites on the human organism and, above all, despite the improvement in sanitary conditions, there is a resurgence of parasitic infections, as evidenced, e.g. by the examples presented in this review.
CONCLUSIONS
The examples of positive effects of parasites presented so far give hope for the future in terms of fighting many diseases for which pharmacological treatment has not yet brought a positive effect. A better understanding of those processes might lead to the development of new methods of unconventional medical treatment.
Topics: Animals; Humans; Medicine; Parasites; Parasitic Diseases
PubMed: 31885223
DOI: 10.26444/aaem/109665 -
Frontiers in Immunology 2020Parasites, bacteria, and viruses pose serious threats to public health. Many parasite infections, including infections of protozoa and helminths, can inhibit... (Review)
Review
Parasites, bacteria, and viruses pose serious threats to public health. Many parasite infections, including infections of protozoa and helminths, can inhibit inflammatory responses and impact disease outcomes caused by viral, bacterial, or other parasitic infections. Type I interferon (IFN-I) has been recognized as an essential immune effector in the host defense against various pathogens. In addition, IFN-I responses induced by co-infections with different pathogens may vary according to the host genetic background, immune status, and pathogen burden. However, there is only limited information on the roles of IFN-I in co-infections with parasites and viruses, bacteria, or other parasites. This review summarizes some recent findings on the roles of IFN-I in co-infections with parasites, including spp., spp., , or , and viruses or bacteria and co-infections with different parasites (such as co-infection with and , and co-infection with spp. and ). The potential mechanisms of host responses associated with co-infections, which may provide targets for immune intervention and therapies of the co-infections, are also discussed.
Topics: Animals; Bacteria; Bacterial Infections; Coinfection; Host-Parasite Interactions; Humans; Interferon Type I; Parasites; Parasitic Diseases; Signal Transduction; Virus Diseases; Viruses
PubMed: 33193291
DOI: 10.3389/fimmu.2020.01805 -
Resetting our expectations for parasites and their effects on species interactions: a meta-analysis.Ecology Letters Jan 2023Despite the ubiquitous nature of parasitism, how parasitism alters the outcome of host-species interactions such as competition, mutualism and predation remains unknown.... (Meta-Analysis)
Meta-Analysis Review
Despite the ubiquitous nature of parasitism, how parasitism alters the outcome of host-species interactions such as competition, mutualism and predation remains unknown. Using a phylogenetically informed meta-analysis of 154 studies, we examined how the mean and variance in the outcomes of species interactions differed between parasitized and non-parasitized hosts. Overall, parasitism did not significantly affect the mean or variance of host-species interaction outcomes, nor did the shared evolutionary histories of hosts and parasites have an effect. Instead, there was considerable variation in outcomes, ranging from strongly detrimental to strongly beneficial for infected hosts. Trophically-transmitted parasites increased the negative effects of predation, parasites increased and decreased the negative effects of interspecific competition for parasitized and non-parasitized heterospecifics, respectively, and parasites had particularly strong negative effects on host species interactions in freshwater and marine habitats, yet were beneficial in terrestrial environments. Our results illuminate the diverse ways in which parasites modify critical linkages in ecological networks, implying that whether the cumulative effects of parasitism are considered detrimental depends not only on the interactions between hosts and their parasites but also on the many other interactions that hosts experience.
Topics: Animals; Parasites; Host-Parasite Interactions; Motivation; Ecosystem; Predatory Behavior
PubMed: 36335559
DOI: 10.1111/ele.14139 -
Molecules (Basel, Switzerland) Oct 2019Parasitic diseases have serious health, social, and economic impacts, especially in the tropical regions of the world. Diseases caused by protozoan parasites are... (Review)
Review
Parasitic diseases have serious health, social, and economic impacts, especially in the tropical regions of the world. Diseases caused by protozoan parasites are responsible for considerable mortality and morbidity, affecting more than 500 million people worldwide. Globally, the burden of protozoan diseases is increasing and is been exacerbated because of a lack of effective medication due to the drug resistance and toxicity of current antiprotozoal agents. These limitations have prompted many researchers to search for new drugs against protozoan parasites. In this review, we have compiled the latest information (2012-2017) on the structures and pharmacological activities of newly developed organic compounds against five major protozoan diseases, giardiasis, leishmaniasis, malaria, trichomoniasis, and trypanosomiasis, with the aim of showing recent advances in the discovery of new antiprotozoal drugs.
Topics: Animals; Antiprotozoal Agents; Drug Resistance; Parasites; Parasitic Diseases
PubMed: 31661934
DOI: 10.3390/molecules24213886 -
Clinical Microbiology Reviews Apr 2014Over the past few decades, nucleic acid-based methods have been developed for the diagnosis of intestinal parasitic infections. Advantages of nucleic acid-based methods... (Review)
Review
Over the past few decades, nucleic acid-based methods have been developed for the diagnosis of intestinal parasitic infections. Advantages of nucleic acid-based methods are numerous; typically, these include increased sensitivity and specificity and simpler standardization of diagnostic procedures. DNA samples can also be stored and used for genetic characterization and molecular typing, providing a valuable tool for surveys and surveillance studies. A variety of technologies have been applied, and some specific and general pitfalls and limitations have been identified. This review provides an overview of the multitude of methods that have been reported for the detection of intestinal parasites and offers some guidance in applying these methods in the clinical laboratory and in epidemiological studies.
Topics: Animals; Humans; Intestinal Diseases, Parasitic; Molecular Diagnostic Techniques; Molecular Epidemiology; Parasites; Parasitology
PubMed: 24696439
DOI: 10.1128/CMR.00122-13 -
Philosophical Transactions of the Royal... Nov 2021Growing evidence suggests that biodiversity mediates parasite prevalence. We have compiled the first global database on occurrences and prevalence of marine parasitism...
Growing evidence suggests that biodiversity mediates parasite prevalence. We have compiled the first global database on occurrences and prevalence of marine parasitism throughout the Phanerozoic and assess the relationship with biodiversity to test if there is support for amplification or dilution of parasitism at the macroevolutionary scale. Median prevalence values by era are 5% for the Paleozoic, 4% for the Mesozoic, and a significant increase to 10% for the Cenozoic. We calculated period-level shareholder quorum sub-sampled (SQS) estimates of mean sampled diversity, three-timer (3T) origination rates, and 3T extinction rates for the most abundant host clades in the Paleobiology Database to compare to both occurrences of parasitism and the more informative parasite prevalence values. Generalized linear models (GLMs) of parasite occurrences and SQS diversity measures support both the amplification (all taxa pooled, crinoids and blastoids, and molluscs) and dilution hypotheses (arthropods, cnidarians, and bivalves). GLMs of prevalence and SQS diversity measures support the amplification hypothesis (all taxa pooled and molluscs). Though likely scale-dependent, parasitism has increased through the Phanerozoic and clear patterns primarily support the amplification of parasitism with biodiversity in the history of life. This article is part of the theme issue 'Infectious disease macroecology: parasite diversity and dynamics across the globe'.
Topics: Animals; Biodiversity; Biological Evolution; Databases, Factual; Fossils; Invertebrates; Marine Biology; Paleontology; Parasites; Vertebrates
PubMed: 34538136
DOI: 10.1098/rstb.2020.0366