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Antiprotozoal Effects of Wild Plants
Published in Mahendra Rai, Shandesh Bhattarai, Chistiane M. Feitosa, Ethnopharmacology of Wild Plants, 2021
Muhammad Subbayyal Akram, Rao Zahid Abbas, José L. Martinez
In the genus Trichomonas, only Trichomonas vaginalis and Trichomonas tenax are causative species in humans and some other species infect animals. Trichomonas vaginalis is a protozoan, pear shaped trophozoites, 10 to 20 μm in length, anaerobic flagellated, which lives in the urogenital tract of humans, commonly vulva, vagina, and urethra of female and epididymis, prostate and urethra of male and replicates in these parts by binary fission. T. vaginalis is the most widespread non-viral sexually transmitted disease in the world, which tentatively infects 250 million people per annum (WHO 2016). Even extragenital infections of T. vaginalis are also reported from respiratory samples of neonates and from the patients suffering from human immunodeficiency virus (HIV) infection (Press et al. 2001). Females are more prone to infection than males with a ratio of 36:1. Females aged 25–44 years were infected in large numbers, with tentatively 60,000 cases of females in 2011 (Salud et al. 2011).
Factors Controlling the Microflora of the Healthy Mouth
Published in Michael J. Hill, Philip D. Marsh, Human Microbial Ecology, 2020
In gingivitis, the maximal depth of the gingival pocket is about 3 mm. Marginal periodontitis is a destructive inflammatory disease with breakdown of the collagen fibers and bone supporting the teeth. Periodontal pockets, often 5 to 10 mm deep, are formed between tooth surface and gingiva by proliferation of epithelium in an apical direction (Figures 2 and 17). Subgingival plaque in such pathological pockets harbors relatively few streptococci and actinomyces, while there is a greater predominance of the obligate anaerobes, Gram-negative rods, and treponemes already mentioned as members of supra- and subgingival plaque in gingivitis (Figures 15 and 23). The protozoa, Entamoeba gingivalis and Trichomonas tenax are also regularly present.48 Some of the species constituting increased percentages of the microflora in advancing, destructive disease have received much attention as possible etiological agents (notably B. gingivalis, B. intermedius, F. nucleatum, A. actinomycetemcomitans, W. recta, and Treponema spp.).12 Actually, a large number of species appear correlated with disease, and different ones are increased in different pockets.8,56
An Overview of Parasite Diversity
Published in Eric S. Loker, Bruce V. Hofkin, Parasitology, 2023
Eric S. Loker, Bruce V. Hofkin
Members of this group of unicellular eukaryotes often live in environments where oxygen is limited and have mitochondria that are much reduced or instead have a hydrogenosome. Flagella are prominent. Several are noteworthy parasites. Consider Giardia lamblia, also referred to as G. intestinalis or G. duodenalis (Figure 2.9A), the causative agent of giardiasis, first seen by van Leeuwenhoek using his microscope to examine his stools in 1681. We have since learned that Giardia does not possess typical mitochondria, and it was originally thought that this organism might have diverged from eukaryotic stock before the ancestral eukaryote had acquired the mitochondrion by primary endosymbiosis. Primary endosymbiosis in this context refers to the acquisition of a bacterium (probably an alpha-proteobacterium) by an ancestral proto-eukaryote, with the metabolically versatile bacterium thereafter serving as the mitochondrion. Although Giardia is still considered to be an early diverging eukaryote, we know today that it possesses a reduced version of the mitochondrion called a mitosome. Mitosomes are double-membrane structures like mitochondria and are almost certainly derived from them, but they lack mitochondrial DNA. They are incapable of aerobic respiration, in keeping with the limited oxygen environment of the small and large intestine in which Giardia lives, but they can still produce ATP. A related group of metamonads, members of the genus Trichomonas, also have modified mitochondria that in their case are considered to be true hydrogenosomes (they do not require oxygen but can still produce ATP, with H2 as a by-product), as described above. Trichomonas tenax inhabiting the mouth is associated with and can worsen periodontal disease. Trichomonas vaginalis is responsible for the common, sexually transmitted infection known as trichomoniasis or “trich,” and is the protist most commonly associated with pathogenicity in industrialized countries. A related species, Pentatrichomonas hominis lives in the large intestine and caecum and is occasionally implicated in causing diarrhea.
Protozoans in subgingival biofilm: clinical and bacterial associated factors and impact of scaling and root planing treatment
Published in Journal of Oral Microbiology, 2020
Marie Dubar, Marie-Laure Zaffino, Thomas Remen, Nathalie Thilly, Lisiane Cunat, Marie-Claire Machouart, Catherine Bisson
The analysis of the periodontal biofilm revealed the presence of many different microorganisms including protozoans. A number of studies have evaluated the presence of protozoans in patients with periodontal diseases and the frequency of detection of Entamoeba gingivalis and Trichomonas tenax varied respectively from 12% to 69% and from 6% to 38.5% according to the authors [2–4]. After the discovery of genetic variation of E. gingivalis in immunocompromised patients by [5], a new subtype of E. gingivalis isolated from samples of patient with periodontitis has been recently identified and named kamaktli variant. The periodontal parameters associated with the presence of this subtype have not been described [5,6]. The differences in collection and identification protocols (microscopic observation/molecular tools), in the study population (adult/children, patients with or without systemic disease) and the inadequate characterization of periodontal diseases make it difficult to draw solid conclusions on the real prevalence of these microorganisms in periodontal disease. Moreover, no studies, except that of Linke’s [7], have detailed the periodontal pocket depth associated with the presence of these protozoans.
Novel therapeutic opportunities for Toxoplasma gondii, Trichomonas vaginalis, and Giardia intestinalis infections
Published in Expert Opinion on Therapeutic Patents, 2023
Francesca Arrighi, Arianna Granese, Paola Chimenti, Paolo Guglielmi
Trichomonas vaginalis is a flagellate protozoan involved in the insurgence of trichomoniasis, an urogenital infection in humans that are the only natural hosts for the parasite [25]. Other species affecting humans, over Trichomonas vaginalis, are Trichomonas tenax, observed in oral gingival and tracheobronchial sites, and Pentatrichomonas hominis isolated from the intestinal tract; however, these are considered nonpathogenic [26]. With respect to T. gondii, T. vaginalis has a simpler life cycle presenting only the trophozoite stage, albeit pseudocysts have been described under stressful conditions [27]. Moreover, T. vaginalis presents hydrogenosomes in spite of mitochondria, as unique energy-producing organelles involved in the metabolism adaptation. T. vaginalis is considered the main non-viral sexually transmitted infection (STI), while transmission via fomites and water has been rarely described [28]. Even though T. vaginalis infected patients are often asymptomatic, this infection may result in a variety of clinical manifestations. In women, the site mainly affected by infection is the vagina, albeit urethra and endocervix are also reached by the trophozoites. As a result, symptoms may include vaginal discharge, pruritus, odor, and irritation up to endometritis, adnexitis, pyosalpinx, and atypical pelvic inflammatory [29]. Moreover, trichomoniasis can also affect the pregnancy course, leading to low birth weight, membrane’s premature rupture, and preterm delivery [30]. In men, the spectrum of trichomoniasis is less well characterized, albeit related with urethritis accompanied by scanty, clear to mucopurulent discharge, dysuria, and mild pruritus. Prostatitis, balanoposthitis, epididymo-orchitis, and possibly infertility are other complications that can occur as consequence of T. vaginalis infection [28]. Finally, an important aspect in T. vaginalis infection is the bidirectional relationship with human immunodeficiency virus (HIV) due to positive association with both HIV transmission and acquisition [31].