Trematoda (flukes)

2017 ◽  
Vol 1 (6) ◽  
pp. 651-657
Author(s):  
Rafael Toledo ◽  
Bernard Fried
Keyword(s):  
Neglected Tropical Diseases ◽  
Animal Health ◽  
Life Cycles ◽  
Diagnostic Features ◽  
Complex Life Cycles ◽  
Mortality And Morbidity ◽  
Digenetic Trematodes ◽  
Asexual Multiplication ◽  
Significant Mortality

The class Trematoda is the largest group of Platyhelminths and includes two subclasses: Aspidogastrea and Digenea. Trematodes, and particularly Digeneans, is a large group of organisms with significant medical and veterinary interest. Over 100 species of digenetic trematodes have been reported infecting humans. Although the significant mortality and morbidity that some of these infections cause, they are among the most neglected tropical diseases. Apart from their impact in public and animal health, the Digenea constitutes an intriguing group of organisms that has a vast interest in experimental biology. Systematics and taxonomy of this group constitute a challenge for biologists in relation to the difficulty entailed in the establishment of phylogenetic relationships between trematodes and the determination of valid diagnostic features. Moreover, their complex life cycles, using at least two hosts and alternating free-living and parasitic stages or sexual and asexual multiplication, constitute a paradigm of how organisms can evolve to become adapted to different biotic and abiotic environments to enhance survival. In this review, we briefly summarize the major features of trematodes in relation to both biological and medical areas.

Pollutant-induced effects on immunological and physiological interactions in aquatic host–trematode systems: implications for parasite transmission

2006 ◽  
Vol 80 (2) ◽  
pp. 137-149 ◽  
Author(s):  
N.J. Morley ◽  
J.W. Lewis ◽  
D. Hoole
Keyword(s):  
Life Cycles ◽  
Economic Importance ◽  
Parasite Transmission ◽  
Combined Stress ◽  
Complex Life Cycles ◽  
Physiological Processes ◽  
Digenetic Trematodes ◽  
Functional Biology ◽  
Parasite Populations ◽  
Pathogenic Effects

AbstractUnder conditions of pollution both host and parasite are susceptible to the pathogenic effects of toxicants, which in turn may result in detrimental changes to their immunological and physiological processes. Digenetic trematodes, which encompass species of both medical and economic importance, possess complex life cycles and are common parasites of both vertebrates and molluscs. The combined stress induced by pollution and parasitism influences the physiology of the host which can have implications not only on host survival but also on the functional biology of resident parasite populations. The present paper reviews the effects of pollutants on the immunology and physiology in both vertebrate and molluscan host–trematode systems and the implications for parasite transmission.

scholarly journals Antikinetoplastid Activity of Indolocarbazoles from Streptomyces sanyensis

Biomolecules ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 657 ◽  
Author(s):  
Luis Cartuche ◽  
Ines Sifaoui ◽  
Atteneri López-Arencibia ◽  
Carlos J. Bethencourt-Estrella ◽  
Desirée San Nicolás-Hernández ◽  
...  
Keyword(s):  
Neglected Tropical Diseases ◽  
Life Cycles ◽  
Complex Life Cycles ◽  
Structure Activity ◽  
The Family ◽  
Mouse Macrophages ◽  
Parasite Survival ◽  
Ic50 Values ◽  
Arcyriaflavin A ◽  
Similar Complex

Chagas disease and leishmaniasis are neglected tropical diseases caused by kinetoplastid parasites of Trypanosoma and Leishmania genera that affect poor and remote populations in developing countries. These parasites share similar complex life cycles and modes of infection. It has been demonstrated that the particular group of phosphorylating enzymes, protein kinases (PKs), are essential for the infective mechanisms and for parasite survival. The natural indolocarbazole staurosporine (STS, 1) has been extensively used as a PKC inhibitor and its antiparasitic effects described. In this research, we analyze the antikinetoplastid activities of three indolocarbazole (ICZs) alkaloids of the family of staurosporine STS, 2–4, and the commercial ICZs rebeccamycin (5), K252a (6), K252b (7), K252c (8), and arcyriaflavin A (9) in order to establish a plausive approach to the mode of action and to provide a preliminary qualitative structure–activity analysis. The most active compound was 7-oxostaurosporine (7OSTS, 2) that showed IC50 values of 3.58 ± 1.10; 0.56 ± 0.06 and 1.58 ± 0.52 µM against L. amazonensis; L. donovani and T. cruzi, and a Selectivity Index (CC50/IC50) of 52 against amastigotes of L. amazonensis compared to the J774A.1 cell line of mouse macrophages.

scholarly journals Culture of Protozoan Parasites

2002 ◽  
Vol 15 (3) ◽  
pp. 327-328 ◽  
Author(s):  
Govinda S. Visvesvara ◽  
Lynne S. Garcia
Keyword(s):  
Strain Differences ◽  
Life Cycle Stage ◽  
Life Cycles ◽  
In Vitro Cultivation ◽  
Protozoan Parasites ◽  
Complex Life Cycles ◽  
Host Parasite Interactions ◽  
Host Parasite

SUMMARY The in vitro culture of protozoan parasites involves highly complex procedures, which are subject to many variables. These parasites have very complex life cycles and, depending on the life cycle stage, may require different culture parameters. However, in vitro cultivation is important for many reasons, some of which include: diagnosis, antigen and antibody production, assessment of parasite immune modulating capabilities, drug screening, improvements in chemotherapy, differentiation of clinical isolates, determination of strain differences, vaccine production, development of attenuated strains, and the continued supply of viable organisms for studying host-parasite interactions.

scholarly journals Tryp-ing up metabolism: role of metabolic adaptations in kinetoplastid disease pathogenesis

2021 ◽  
Author(s):  
Adwaita R. Parab ◽  
Laura-Isobel McCall
Keyword(s):  
Neglected Tropical Diseases ◽  
Life Cycles ◽  
Mammalian Host ◽  
Tropical Diseases ◽  
Disease Pathogenesis ◽  
Complex Life Cycles ◽  
Metabolic Adaptations ◽  
Key Factor

Today, more than a billion people – one-sixth of the world’s population – are suffering from neglected tropical diseases. Human African trypanosomiasis, Chagas disease, and leishmaniasis are neglected tropical diseases caused by protozoan parasites belonging to the genera Trypanosoma and Leishmania. About half a million people living in tropical and subtropical regions of the world are at risk of contracting one of these three infections. Kinetoplastids have complex life cycles with different morphologies and unique physiological requirements at each lifecycle stage. This review covers the latest findings on metabolic pathways impacting disease pathogenesis of kinetoplastids within the mammalian host. Nutrient availability is a key factor shaping in vivo parasite metabolism; thus, kinetoplastids display significant metabolic flexibility. Proteomic and transcriptomic profiles show that intracellular trypanosomatids are able to switch to an energy-efficient metabolism within the mammalian host system. Host metabolic changes can also favor parasite persistence, and contribute to symptom development, in a location-specific fashion. Ultimately, targeted and untargeted metabolomics studies have been a valuable approach to elucidate the specific biochemical pathways affected by infection within the host, leading to translational drug development and diagnostic insights.

Tranmission pattern differences of miracidia and cercariae larval stages of digenetic trematode parasites

2016 ◽  
Vol 61 (4) ◽  
Author(s):  
Michael R. Zimmermann ◽  
Kyle E. Luth ◽  
Gerald W. Esch
Keyword(s):  
Abiotic Factors ◽  
Field Studies ◽  
Life Cycles ◽  
Digenetic Trematode ◽  
Snail Species ◽  
Intermediate Hosts ◽  
Complex Life Cycles ◽  
Larval Stages ◽  
Digenetic Trematodes ◽  
Trematode Parasites

AbstractDigenetic trematodes have complex life cycles involving multiple hosts and free-living larval stages. Some species have 2 lar-val stages that infect snails, with miracidia and cercariae using these molluscs as first and second intermediate hosts, respec-tively. Although both larval stages may infect the same snail species, this is accomplished using different chemical cues and may be influenced by different biotic and abiotic factors. Significant differences in the infection patterns of these parasitic stages regarding host size and density were observed in 2 separate field studies. The prevalence of sporocysts/rediae and mean abundance of

Definitions and concepts of reproductive biology of diatoms (terminological glossary)

2017 ◽  
Vol 51 ◽  
pp. 71-105 ◽  
Author(s):  
N. A. Davidovich
Keyword(s):  
Mating System ◽  
Sexual Reproduction ◽  
Reproductive Biology ◽  
World Literature ◽  
Russian Literature ◽  
Life Cycles ◽  
Transfer Of Knowledge ◽  
Research Experience ◽  
Key Terms

The absence of a conceptual terminology, sufficiently developed and widely accepted in the Russian literature, significantly hinders progress in the field of reproductive biology of diatoms, restricts communication and debate, prevents training and transfer of knowledge. The present work is an attempt, based on world literature and our own research experience, to summarize, systematize, add, and clarify the existing terms, concepts and definitions related to research which are focused on sex and sexual reproduction in diatoms. A glossary of key terms (more than 200, including synonyms) is provided. Terms refer to diatom reproductive biology, life cycles, fertilization, mating system, gender (including inheritance and determination of sex, as well as inheritance associated with sex). Contradictions between possible interpretations of certain terms are briefly discussed.

Development and Validation of a Stability-Indicating Chromatographic Method for the Determination of Indacaterol Maleate with Glycopyrronium Bromide in Mixture

2019 ◽  
Vol 15 (7) ◽  
pp. 694-702
Author(s):  
Sonia Talaat Hassib ◽  
Hanaa Abdelmenem Hashem ◽  
Marwa Ahmed Fouad ◽  
Nehal Essam Eldin Mohamed
Keyword(s):  
Chromatographic Method ◽  
Degradation Products ◽  
Reversed Phase ◽  
Chronic Obstructive ◽  
Forced Degradation ◽  
Uv Detector ◽  
Obstructive Pulmonary Disease ◽  
Mortality And Morbidity ◽  
Glycopyrronium Bromide

Introduction: (COPD) Chronic Obstructive Pulmonary Disease is a partially reversible and treatable lung disease, characterized by progressive limitation of airflow. It is one of the main causes of mortality and morbidity worldwide. Methods: An easy, precise and selective reversed-phase liquid chromatographic method, with stabilityindicating assay was established and validated for the determination of indacaterol maleate and glycopyrronium bromide in the mixture. In addition, a forced degradation study was performed for indacaterol maleate, comprised of hydrolysis by acid and base, degradation by oxidation and heat, and photo-degradation. Separation and forced degradation were done by isocratic elution using a reversed phase phenyl column and (methanol: phosphate buffer) at ratio (65:35, v/v) with 3.5 pH buffer as an eluent at 1 mL min-1 as a flow rate. Quantitation was accomplished using a UV detector at 210 nm. Results: The method showed good separation of glycopyrronium bromide, indacaterol maleate and its degradation products. Accuracy, linearity, and precision were acceptable over 10-160 µg mL-1 and 10- 80 µg mL-1 concentration range for indacaterol maleate and glycopyrronium bromide, respectively. Conclusion: The proposed method does not require any previously done separation steps, making it applicable for the analysis of the drugs under investigation in their pharmaceutically marketed preparations.

scholarly journals Defence Medical Rehabilitation Centre (DMRC) COVID-19 Recovery Service

2021 ◽  
pp. e001681
Author(s):  
Oliver O'Sullivan ◽  
R Barker-Davies ◽  
R Chamley ◽  
E Sellon ◽  
D Jenkins ◽  
...  
Keyword(s):  
Occupational Medicine ◽  
Armed Forces ◽  
Acute Illness ◽  
Medical Rehabilitation ◽  
Rehabilitation Centre ◽  
Operational Effectiveness ◽  
Mortality And Morbidity ◽  
Recovery Service ◽  
Significant Mortality

Coronavirus disease 2019 (COVID-19) causes significant mortality and morbidity, with an unknown impact in the medium to long term. Evidence from previous coronavirus epidemics indicates that there is likely to be a substantial burden of disease, potentially even in those with a mild acute illness. The clinical and occupational effects of COVID-19 are likely to impact on the operational effectiveness of the Armed Forces. Collaboration between Defence Primary Healthcare, Defence Secondary Healthcare, Defence Rehabilitation and Defence Occupational Medicine resulted in the Defence Medical Rehabilitation Centre COVID-19 Recovery Service (DCRS). This integrated clinical and occupational pathway uses cardiopulmonary assessment as a cornerstone to identify, diagnose and manage post-COVID-19 pathology.

scholarly journals Characterization and Quantification of Selenoprotein P: Challenges to Mass Spectrometry

2021 ◽  
Vol 22 (12) ◽  
pp. 6283
Author(s):  
Jérémy Lamarche ◽  
Luisa Ronga ◽  
Joanna Szpunar ◽  
Ryszard Lobinski
Keyword(s):  
Mass Spectrometry ◽  
State Of The Art ◽  
Animal Health ◽  
Primary Standard ◽  
Selenoprotein P ◽  
Primary Standards ◽  
Analytical Approaches ◽  
Careful Investigation ◽  
Accurate Quantification

Selenoprotein P (SELENOP) is an emerging marker of the nutritional status of selenium and of various diseases, however, its chemical characteristics still need to be investigated and methods for its accurate quantitation improved. SELENOP is unique among selenoproteins, as it contains multiple genetically encoded SeCys residues, whereas all the other characterized selenoproteins contain just one. SELENOP occurs in the form of multiple isoforms, truncated species and post-translationally modified variants which are relatively poorly characterized. The accurate quantification of SELENOP is contingent on the availability of specific primary standards and reference methods. Before recombinant SELENOP becomes available to be used as a primary standard, careful investigation of the characteristics of the SELENOP measured by electrospray MS and strict control of the recoveries at the various steps of the analytical procedures are strongly recommended. This review critically discusses the state-of-the-art of analytical approaches to the characterization and quantification of SELENOP. While immunoassays remain the standard for the determination of human and animal health status, because of their speed and simplicity, mass spectrometry techniques offer many attractive and complementary features that are highlighted and critically evaluated.

scholarly journals Impacts of climate change on the complex life cycles of fish

2012 ◽  
Vol 22 (2) ◽  
pp. 121-139 ◽  
Author(s):  
Pierre Petitgas ◽  
Adriaan D. Rijnsdorp ◽  
Mark Dickey-Collas ◽  
Georg H. Engelhard ◽  
Myron A. Peck ◽  
...  
Keyword(s):  
Climate Change ◽  
Life Cycles ◽  
Complex Life Cycles ◽  
Impacts Of Climate Change
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