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Parasitology International Apr 2020Proliferative sparganosis is one of the most bizarre and mysterious parasitic diseases ever described. The causative parasite is Sparganum proliferum, which is a... (Review)
Review
Proliferative sparganosis is one of the most bizarre and mysterious parasitic diseases ever described. The causative parasite is Sparganum proliferum, which is a pseudophyllidean cestode distinct from Spirometra tapeworms. Here we overview this rare but fascinating disease with the all original case reports on human patients published in the last 115 years. Proliferative sparganosis is clearly divided into two disease types, cutaneous and internal proliferative sparganosis. Cutaneous type starts with a skin eruption caused by the dermal invasion of a sparganum. Skin lesion progresses to larger areas of the body if left untreated. Various internal organs and body wall can be eventually affected. The clinical symptoms of patients in this group are very similar to each other. Molecular data suggest that cutaneous proliferative sparganosis is caused by S. proliferum of which genetic variation is limited, regardless of the time or localities of the emergence of patients. Internal proliferative sparganosis, on the other hand, is much more heterogeneous. Some cases show aggressive infection in internal organs, while others show only restricted lesions. Some of the cases that had been cited as proliferative sparganosis in the past literature were removed from the list, because they were judged as cyclophyllidean tapeworm infections. DNA sequencing is mandatory for the definite diagnosis of proliferative sparganosis. The Venezuelan strain of S. proliferum is maintained in experimental mice in Japan, which is fully prepared for the experimental study with advanced technologies in modern molecular biology.
Topics: Animals; Humans; Skin Diseases, Parasitic; Sparganosis; Sparganum
PubMed: 31841658
DOI: 10.1016/j.parint.2019.102036 -
PLoS Pathogens Nov 2019The shape and number of mitochondria respond to the metabolic needs during the cell cycle of the eukaryotic cell. In the best-studied model systems of animals and fungi,... (Review)
Review
The shape and number of mitochondria respond to the metabolic needs during the cell cycle of the eukaryotic cell. In the best-studied model systems of animals and fungi, the cells contain many mitochondria, each carrying its own nucleoid. The organelles, however, mostly exist as a dynamic network, which undergoes constant cycles of division and fusion. These mitochondrial dynamics are driven by intricate protein machineries centered around dynamin-related proteins (DRPs). Here, we review recent advances on the dynamics of mitochondria and mitochondrion-related organelles (MROs) of parasitic protists. In contrast to animals and fungi, many parasitic protists from groups of Apicomplexa or Kinetoplastida carry only a single mitochondrion with a single nucleoid. In these groups, mitochondrial division is strictly coupled to the cell cycle, and the morphology of the organelle responds to the cell differentiation during the parasite life cycle. On the other hand, anaerobic parasitic protists such as Giardia, Entamoeba, and Trichomonas contain multiple MROs that have lost their organellar genomes. We discuss the function of DRPs, the occurrence of mitochondrial fusion, and mitophagy in the parasitic protists from the perspective of eukaryote evolution.
Topics: Animals; Mitochondrial Dynamics; Parasites; Parasitic Diseases
PubMed: 31751405
DOI: 10.1371/journal.ppat.1008008 -
Parasitology Sep 2022In the present paper, we review two of the most neglected intestinal food-borne trematodiases: echinostomiasis, caused by members of the family Echinostomatidae, and... (Review)
Review
In the present paper, we review two of the most neglected intestinal food-borne trematodiases: echinostomiasis, caused by members of the family Echinostomatidae, and gastrodiscoidiasis produced by the amphistome . Both parasitic infections are important intestinal food-borne diseases. Humans become infected after ingestion of raw or insufficiently cooked molluscs, fish, crustaceans, amphibians or aquatic vegetables. Thus, eating habits are essential to determine the distribution of these parasitic diseases and, traditionally, they have been considered as minor diseases confined to low-income areas, mainly in Asia. However, this scenario is changing and the population at risk are currently expanding in relation to factors such as new eating habits in developed countries, growing international markets, improved transportation systems and demographic changes. These aspects determine the necessity of a better understanding of these parasitic diseases. Herein, we review the main features of human echinostomiasis and gastrodiscoidiasis in relation to their biology, epidemiology, immunology, clinical aspects, diagnosis and treatment.
Topics: Animals; Echinostomatidae; Echinostomiasis; Humans; Parasitic Diseases; Trematoda; Trematode Infections
PubMed: 35343418
DOI: 10.1017/S0031182022000385 -
Turkiye Parazitolojii Dergisi Jun 2020MicroRNAs (miRNAs), as epigenetic regulators, are small non-coding RNAs regulating gene expression in eukaryotes at the post-transcriptional level to control biological... (Review)
Review
MicroRNAs (miRNAs), as epigenetic regulators, are small non-coding RNAs regulating gene expression in eukaryotes at the post-transcriptional level to control biological functions. MicroRNAs play a role in development, physiology, infection, immunity and the complex life cycles of parasites. Also, parasite infection can alter host miRNA expression that might result in either parasite clearance or infection. Over the past 20 years, thousands of miRNAs have been identified in the nematode and other parasites. Thus, miRNA pathways are potential targets for the diagnostic and therapeutic control of parasitic diseases. Here, we review the current status and potential functions of miRNAs related to protozoans, helminths, and arthropods.
Topics: Animals; Arthropods; Caenorhabditis elegans; Helminths; Humans; MicroRNAs; Parasites; Parasitic Diseases; RNA, Protozoan
PubMed: 32482043
DOI: 10.4274/tpd.galenos.2020.6776 -
Parasites & Vectors Jun 2021Parasites, including viruses, bacteria, fungi, protists, helminths, and arthropods, are ubiquitous in the animal kingdom. Consequently, hosts are frequently infected... (Review)
Review
Parasites, including viruses, bacteria, fungi, protists, helminths, and arthropods, are ubiquitous in the animal kingdom. Consequently, hosts are frequently infected with more than one parasite species simultaneously. The assessment of such co-infections is of fundamental importance for disease ecology, but relevant studies involving non-domesticated animals have remained scarce. Many amphibians are in decline, and they generally have a highly diverse parasitic fauna. Here we review the literature reporting on field surveys, veterinary case studies, and laboratory experiments on co-infections in amphibians, and we summarize what is known about within-host interactions among parasites, which environmental and intrinsic factors influence the outcomes of these interactions, and what effects co-infections have on hosts. The available literature is piecemeal, and patterns are highly diverse, so that identifying general trends that would fit most host-multiparasite systems in amphibians is difficult. Several examples of additive, antagonistic, neutral, and synergistic effects among different parasites are known, but whether members of some higher taxa usually outcompete and override the effects of others remains unclear. The arrival order of different parasites and the time lag between exposures appear in many cases to fundamentally shape competition and disease progression. The first parasite to arrive can gain a marked reproductive advantage or induce cross-reaction immunity, but by disrupting the skin and associated defences (i.e., skin secretions, skin microbiome) and by immunosuppression, it can also pave the way for subsequent infections. Although there are exceptions, detrimental effects to the host are generally aggravated with increasing numbers of co-infecting parasite species. Finally, because amphibians are ectothermic animals, temperature appears to be the most critical environmental factor that affects co-infections, partly via its influence on amphibian immune function, partly due to its direct effect on the survival and growth of parasites. Besides their importance for our understanding of ecological patterns and processes, detailed knowledge about co-infections is also crucial for the design and implementation of effective wildlife disease management, so that studies concentrating on the identified gaps in our understanding represent rewarding research avenues.
Topics: Amphibians; Animals; Animals, Wild; Coinfection; Host-Parasite Interactions; Parasites; Parasitic Diseases, Animal
PubMed: 34082796
DOI: 10.1186/s13071-021-04796-1 -
Immunology Dec 2020The circadian clock provides organisms with the ability to track time of day, allowing them to predict and respond to cyclical changes in the external environment. In... (Review)
Review
The circadian clock provides organisms with the ability to track time of day, allowing them to predict and respond to cyclical changes in the external environment. In mammals this clock consists of multiple auto-regulatory feedback loops generated by a network of circadian clock proteins. This network provides the fundamental basis for rhythms in behaviour and physiology. This clockwork machinery exists in most cells, including those of the immune system. In recent years evidence has emerged highlighting the important role of molecular clocks in dictating the response of immune pathways. While initial work highlighted the effect of the clock in the 'first line of defence', the innate immune system, it has become increasingly apparent that it also plays a role in the more tailored, later-stage adaptive immune response. This review provides an overview of the role of the circadian cycle in the adaptive immune response. We interrogate the depth of knowledge on cell intrinsic clocks within adaptive immune cells and how these cells may be temporally directed by extrinsic rhythmic signals. We discuss the role of the circadian clock in diseases associated with adaptive immunity such as multiple sclerosis, asthma and parasitic infection. We also discuss the current knowledge on timing of vaccination, and the implications this may have on how we can harness and modulate temporal gating of the adaptive immune response in a clinical setting.
Topics: Adaptive Immunity; Animals; Asthma; Circadian Rhythm; Homeostasis; Humans; Multiple Sclerosis; Parasitic Diseases
PubMed: 31837013
DOI: 10.1111/imm.13167 -
Infectious Diseases of Poverty Apr 2020Chagas disease remains a serious problem for public health due to the high disease burden together with its global spreading patterns. However, current treatment and...
Chagas disease remains a serious problem for public health due to the high disease burden together with its global spreading patterns. However, current treatment and vector control are highly challenged by drug and insecticide resistance. Chemotherapy and vector control have been proved to be effective attempts to minimize the disease burden. Continued efforts are necessary to keep adapting the surveillance-response systems to the dynamic health systems. More attention and investments are needed to improve appropriate strategy and technology in different settings. This may be accomplished by creating effective risk early warning, addressing vulnerability and building resilience systems, implementing a vector surveillance system, as well as innovating research and technology.
Topics: Animals; Chagas Disease; Disease Vectors; Global Health; Humans
PubMed: 32336294
DOI: 10.1186/s40249-020-00658-7 -
ELife Mar 2022Antibodies targeting the protein that causes placental malaria can recognise multiple variants of the protein, which may help guide the development of new vaccines to...
Antibodies targeting the protein that causes placental malaria can recognise multiple variants of the protein, which may help guide the development of new vaccines to protect pregnant women from malaria.
Topics: Antibodies, Protozoan; Female; Humans; Malaria; Malaria, Falciparum; Placenta; Pregnancy; Pregnancy Complications, Parasitic
PubMed: 35344481
DOI: 10.7554/eLife.77751 -
Parasitology Research Jul 2019Coccidiosis is a parasitic disease of a wide variety of animals caused by coccidian protozoa. The coccidia are responsible for major economic losses of the livestock... (Review)
Review
Coccidiosis is a parasitic disease of a wide variety of animals caused by coccidian protozoa. The coccidia are responsible for major economic losses of the livestock industry. For example, the annual cost due to coccidiosis to the global poultry industry has been estimated to exceed US$ 3 billion annually. Currently available drugs for the control of this disease are either polyether ionophorous antibiotics that are derived from fermentation products, or synthetic compounds, produced by chemical synthesis. Unfortunately, no new drugs in either category have been approved for use for decades. Resistance has been documented for all those of the drugs currently employed and therefore the discovery of novel drugs with unique modes of action is imperative if chemotherapy is to remain the principal means to control this disease. This chapter aims to give an overview of the efficacy and mode of action of the current compounds used to control coccidiosis in livestock and provides a brief outlook of research needs for the future.
Topics: Animals; Coccidia; Coccidiosis; Coccidiostats; Livestock; Poultry; Poultry Diseases
PubMed: 31152233
DOI: 10.1007/s00436-019-06343-5 -
Frontiers in Immunology 2022Parasitic infections of the central nervous system are an important cause of morbidity and mortality in Africa. The neurological, cognitive, and psychiatric sequelae of... (Review)
Review
Parasitic infections of the central nervous system are an important cause of morbidity and mortality in Africa. The neurological, cognitive, and psychiatric sequelae of these infections result from a complex interplay between the parasites and the host inflammatory response. Here we review some of the diseases caused by selected parasitic organisms known to infect the nervous system including , , spp., and species. For each parasite, we describe the geographical distribution, prevalence, life cycle, and typical clinical symptoms of infection and pathogenesis. We pay particular attention to how the parasites infect the brain and the interaction between each organism and the host immune system. We describe how an understanding of these processes may guide optimal diagnostic and therapeutic strategies to treat these disorders. Finally, we highlight current gaps in our understanding of disease pathophysiology and call for increased interrogation of these often-neglected disorders of the nervous system.
Topics: Animals; Parasites; Parasitic Diseases; Plasmodium falciparum; Toxoplasma; Trypanosoma brucei brucei
PubMed: 35222377
DOI: 10.3389/fimmu.2022.791488