Comparative analysis of the incidence of enteroparasitosis andthe COVID-19 pandemic profile in the city of Bananeiras - PB / Análise comparativa da incidência de enteroparasitoses e doperfil pandêmico da COVID-19 na cidade de Bananeiras - PB

Enteroparasitosis are diseases caused by parasitic agents present in the environment and in the gastrointestinal tract of living beings. In addition, they are still considered neglected diseases, but of great importance for public health, especially when they are related to secondary infections and currently their co-infection profile with COVID-19. The interaction of protozoa and/or helminths with the SARS-CoV-2 virus is timely and its signs and symptoms are confused with other pathogen relationships. In this way, this study aims to correlate the incidence of enteroparasitosis and COVID-19, in the pandemic period from 2020 to April 2022. This is a documentary and exploratory study of secondary data from laboratory tests of patients who were treated and diagnosed with COVID-19 and enteroparasitosis at Hospital Doutor Cloves Bezerra Cavalcante, Municipal Hospital of Bananeiras, Paraíba, Brazil. In the analysis of the database, a significant increase of approximately 48.85% in the incidence of COVID-19 cases from 2020 to 2021 stands out, remaining high until 2022. In contrast, cases of enteroparasites peaked at 48.74% in 2021, followed by an average reduction of 23.12%, with a deviation of 1.49%, in relation to the years 2020 and 2022. It was concluded that COVID-19 is predominantly associated with an increase in secondary infections, highlighting the crucial need to promote health education, improve basic sanitation and guarantee access to health services as essential components in combating the increase in parasitic infections, especially those related to viral pathologies.

As enteroparasitoses são enfermidades originadas por agentes parasitários presentes no meio ambiente e no trato gastrointestinal dos seres vivos. Ademais, ainda são consideradas doenças negligenciadas, porém de grande importância para a saúde pública, em especial, quando estão relacionadas com infecções secundárias e atualmente seu perfil de coinfecção com a COVID-19. A interação de protozoários e/ou helmintos com o vírus SARS-CoV-2 é oportuna e seus sinais e sintomas são confundidos com outras relações de patógenos. Desta maneira, este estudo visa correlacionar a incidência de enteroparasitoses e COVID-19, no período pandêmico de 2020 a abril de 2022. Trata--se de uma pesquisa documental e exploratória, de dados secundários dos exames laboratoriais de pacientes que foram atendidos e diagnosticados com COVID-19 e enteroparasitoses no Hospital Doutor Cloves Bezerra Cavalcante, Hospital Municipal de Bananeiras, Paraíba, Brasil. Na análise da base de dados, destaca-se um aumento significativo de aproximadamente 48,85% na incidência de casos de COVID-19 de 2020 a 2021, mantendo-se elevado até 2022. Em contraste, os casos de enteroparasitas atingiram um pico de 48,74% em 2021, seguido por uma redução média de 23,12%, com um desvio de 1,49%, em relação aos anos de 2020 e 2022. Conclui-se que a COVID-19 está predominantemente associada ao aumento de infecções secundárias, destacando a necessidade crucial de promover a educação em saúde, melhorar o saneamento básico e garantir o acesso aos serviços de saúde como componentes essenciais no combate ao aumento de infecções parasitárias, especialmente aquelas relacionadas a patologias virais.

Extracellular vesicles as biomarkers in parasitic disease diagnosis.

Parasitic diseases constitute a major global health problem, affecting millions of people worldwide. Recent advances in the study of extracellular vesicles (EVs) have opened up new strategies for biomarker discovery in protozoan and helminth infections. Analyses of EVs in cultures and biological fluids have identified numerous potential biomarkers that could be useful for early and differential diagnosis, monitoring therapeutic responses, and the overall management and control of these diseases. Despite the potential of these biomarkers, several challenges must be addressed, including limited research, the need for standardized protocols, and the reproducibility of results across studies. In many parasitic infections, EVs have been obtained from various sample types, including plasma from human patients and mouse models, as well as cultures of the parasites at different stages. EVs were isolated by various methods and predominantly characterized through proteomic analysis or RNA sequencing to assess their cargo and identify potential biomarkers. These biomarker candidates were investigated and validated using different assays such as ELISA, Western Blot, and ROC curves. Overall, the use of EVs is considered a promising new diagnostic strategy for parasite infections, but further research with larger cohorts, standardized methods, and additional validation tests are essential for effective diagnosis and management of these diseases.

Passive sampling of microbes in various water sources: A systematic review.

Traditional methods for monitoring pathogens in environmental waters have numerous drawbacks. Sampling approaches that are low-cost and time efficient that can capture temporal variation in microbial contamination are needed. Passive sampling of aquatic environments has shown promise as an alternative water monitoring technique for waterborne pathogens and microbial contaminants. The present systematic review aimed to compile and synthesize existing literature on the use of passive samplers for the monitoring of microbes in different water sources and identify research gaps. The review summarizes current knowledge on materials used for detection, deployment durations, analytical methods, quantification as well as benefits and limitations of passive sampling. This review found that electronegative nitrocellulose membrane filters are effective for both detection and quantification of viruses in wastewater, while gauze passive samplers have been effective for detecting bacterial targets in wastewater. There is a large knowledge gap in the use of passive samplers in a quantitative manner, especially for the back-calculation of water-column microbial concentrations or for correlation to outcomes of interest (e.g. prevalence rates). Further, there is very limited attention paid to the use of membrane filters for the monitoring of bacteria in any water source as well as a lack of studies utilizing passive sampling approaches for protozoa.

Molecular detection and identification of Enteromonas species in human and animal hosts using polymerase chain reaction and DNA sequencing.

Enteromonas hominis, a human intestinal protozoan parasite of the diplomonad group, has been overlooked because of its commensal features; therefore, molecular studies on this parasite are limited. To address this gap, we designed a molecular screening protocol using polymerase chain reaction (PCR) and DNA sequencing targeting the 18S small subunit ribosomal RNA gene and applied this screening method to the molecular epidemiological analysis of Enteromonas spp. in humans and various livestock. We validated our methodology using stool samples collected from 215 humans and 270 animal hosts (buffaloes, pigs, dogs, goats, horses, rodents, chickens, and ducks) during an annual epidemiological investigation conducted from 2013 to 2016 on Sumba Island, Indonesia. The overall prevalences of Enteromonas spp. were 33.9 % (n = 73/215) in humans and 25.2 % (n = 68/270) in mammals and avians. The positive predictive value of this PCR method for Enteromonas spp., as evaluated through sequencing, was 90.1 % in human samples and 58.1 % in non-human samples (particularly low, 11.4 % in rodents). Although the specificity of the PCR approach may not be perfect, in combination with DNA sequencing, it was effective in detecting and identifying a partial sequence (1458 bp) of the target gene region in Enteromonas species.

Prevalence of Entamoeba histolytica/dispar and Giardia lamblia infections and their associated factors among schoolchildren in the Amhara region, Northwest Ethiopia.

Globally, intestinal protozoa E. histolytica/dispar and Giardia lamblia are the cause of amoebiasis and giardiasis, respectively. Despite their important medical importance and common occurrence in Ethiopia, they are minimally addressed in terms of their prevalence, sensitive diagnostic methods, and associated risk factors. Infections with E. histolytica/dispar and G. lamblia are often misdiagnosed and underreported in impoverished countries. Thus, the purpose of this study was to ascertain the prevalence of Giardia lamblia and E. histolytica/dispar infections as well as related variables among schoolchildren in the Amhara region. A cross-sectional study was conducted among 844 schoolchildren in the Amhara region from April to December 2019. A stool sample was collected from each study participant and processed via the formol ether concentration technique (FECT) and spontaneous tube sedimentation techniques (STST). Data were entered in EpiData and analysed by SPSS statistical software. The prevalence of E. histolytica and G. lamblia infections using each diagnostic method and composite reference was determined by descriptive statistics. The association of risk factors with E. histolytica/dispar and G. lamblia infections was analysed by logistic regression and variables with p < 0.05 were considered to have statistical significance. From the total, 243 (28.8%) schoolchildren were found to be infected by at least one of E. histolytica/dispar or G. lamblia. The prevalence of E. histolytica/dispar and G. lamblia infections was 201 (23.8%) and 62 (7.3%), respectively. The co-infection prevalence with both E. histolytica/dispar and G. lamblia was 22 (2.6%). The sensitivity (78.6%) and negative predictive value of STST (19.6%) were higher than FECT sensitivity (65.4%) and negative predictive value (13.1%). Children in 10-14 years of age (AOR = 1.66;95%CI: 1.16-2.38), lived in the rural (AOR = 1.97;95%CI: 1.12-3.49), used latrine improperly (AOR = 1.49;95%CI: 1.04-2.13), did not wash hands before meal (AOR = 2.10; 95%CI:1.08-4.10), and after latrine (AOR = 1.51;95%CI: 1.05-2.19), ate unwashed raw vegetables (AOR = 1.85;95%CI:1.26-2.70), and played with soil (AOR = 1.48;95%CI:1.06-2.06) were associated with E. histolytica/dispar and G. lamblia infection. These findings revealed high prevalence of E. histolytica/dispar and G. lamblia infections was high in the Amhara region. Therefore, proper implementation of water, sanitation and hygiene should be advocated at the community and school levels to mitigate the disease burden.

Wastewater-based intestinal protozoa monitoring in Shanghai, China.

Intestinal protozoa Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi have been implicated in serious waterborne outbreaks worldwide. Wastewater-based epidemiology (WBE) is a promising approach for evaluating the disease prevalence in a catchment population in that it monitors the contamination level of the intestinal pathogens in wastewater. We collected 48 urban wastewater samples (24 from influents and 24 from effluents) from the Yangpu Wastewater Treatment Plant (YPWTP) in Shanghai, China. We identified Cryptosporidium spp., G. duodenalis, and E. bieneusi by nested polymerase chain reaction (PCR) amplification. Cryptosporidium hominis and subtype IdA14 were identified in two samples by analyzing the sequences of small subunit ribosomal RNA (SSU rRNA) and 60-kDa glycoprotein (gp60) genes, respectively. The G. duodenalis sub-assemblage AII (n = 8) and assemblage C (n = 4) in 12 samples were determined by analyzing triosephosphate isomerase (tpi) gene sequences. The E. bieneusi genotype A was identified in one sample by analyzing the sequence of the internal transcribed spacer (ITS) region of the rRNA gene. These findings suggest that improving wastewater treatment and monitoring the virility of pathogens in effluents is critical. We observed similar prevalence and genotypes/subtypes of the three intestinal protozoa in our wastewater samples as those reported in previous studies, providing evidence that WBE can be used as an effective epidemic management tool.IMPORTANCECryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi are common intestinal protozoa causing diarrhea. The infective oocysts, cysts, and spores released in feces can survive in different environments, including multiple types of water bodies. Humans can acquire these intestinal protozoan infections via the fecal-oral route as in waterborne transmission. Wastewater-based epidemiology can rapidly and reliably detect and monitor the emergence and spread of waterborne diseases. We detected Cryptosporidium spp., G. duodenalis, and E. bieneusi in a wastewater treatment plant in Shanghai, China, reflecting the occurrence and genetic characterizations of the three intestinal pathogens from community members served by the wastewater treatment plant.

Improved and easy method for long-term in vitro culture of rumen ciliates Dasytricha ruminantium.

The rumen ciliates are a diverse group of protozoa residing in the rumen of ruminant animals. They are primarily found in the orders Entodiniomorphida and Vestibuliferida, playing crucial roles in the digestion and breakdown of feed within the host's rumen, closely intertwined with the host's nutrient absorption. In vitro monocultures of representatives of rumen ciliates are important to better study them. So far, Entodinium caudatum and Epidinium caudatum, representatives of the order Entodiniomorphida, have been successfully cultivated as a monoculture in vitro. However, for the order Vestibuliferida, no representative species has been established a stable monoculture in vitro up to date, which hampers to study their physiology and metabolism. Therefore, we have developed a simple method for the in vitro cultivation of Dasytricha ruminantium, a representative rumen ciliate in the order Vestibuliferida. Utilizing an optimized culture medium with easily obtainable components, and the cultivation process is simple. This will facilitate further research in metabolism and other studies requiring large pure live materials.1.Filtration and separation for enriching D. ruminantium.2.A culture medium (DRM) suitable for the growth of D. ruminantium, with easily obtainable components.3.Simple cultivation process, facilitating the obtainment of a large number of monocultured D. ruminantium.

Auranofin is lethal against feline Tritrichomonas foetus in vitro but ineffective in cats with naturally occurring infection.

Protozoal diarrhea caused by Tritrichomonas foetus (blagburni) is a prevalent, lifelong, and globally distributed burden in domestic cats. Treatment is limited to the use of 5-nitroimidazoles and treatment failure is common. The repurposed gold salt compound auranofin has killing activity against diverse protozoa in vitro but evidence of efficacy in naturally occurring protozoal infections is lacking. This exploratory study investigated the efficacy and safety of auranofin for treatment of cats with naturally occurring, 5-nitroimidazole-resistant, T. foetus infection. The minimum lethal concentration (MLC) of auranofin against 5 isolates of feline T. foetus was determined under aerobic conditions in vitro. Healthy cats and cats with T. foetus infection were treated with immediate release auranofin (range, 0.5-3 mg/cat for 7 days) or guar gum-coated auranofin capsules (0.5 or 3 mg/cat for 7 days). Adverse effects were monitored by clinical signs and clinicopathologic testing. Efficacy was determined by fecal consistency score, bowel movement frequency, and single-tube nested PCR of feces for T. foetus rDNA. Fecal samples were assayed for concentrations of auranofin, known and predicted metabolites of auranofin, gold containing molecules, and total gold content using HPLC, LC-MS, ion mobility-MS, and ICP-MS, respectively. Auranofin was effective at killing isolates of feline T. foetus at MLC ≥ 1 µg/ml. Treatment of cats with T. foetus infection with either immediate release auranofin or a colon-targeted guar gum-coated tablet of auranofin did not eradicate infection. Treatment failure occurred despite fecal concentrations of gold that met or exceeded the equivalent MLC of auranofin. Neither auranofin, known or predicted metabolites of auranofin, nor any gold-containing molecules >100 Da could be detected in fecal samples of treated cats. Adverse effects associated with auranofin treatment were common but minor. These studies identify that in vitro susceptibility test results of auranofin may not translate to treatment effectiveness in vivo even when achieving gold concentrations equivalent to the MLC of auranofin in the target environment. These studies further establish the absence of any predicted or unpredicted gold containing metabolites in feces after oral administration of auranofin.

Evaluation of the Allplex GI Parasite and Helminth PCR Assay in a Belgian Travel Clinic.

Recently a number of broad-range stool parasite PCR assays have been developed. However, there is ongoing disagreement regarding their diagnostic performance, as various studies have produced contradictory results. In this study, we compared the diagnostic accuracy of the Seegene Allplex GI-Parasite and Allplex GI-Helminth assays (SA) with the conventional methods used at the travel clinic of the Institute of Tropical Medicine (ITM) including microscopy, antigen testing, and molecular detection in order to provide insights into the strengths and limitations of this diagnostic tool which may be crucial to select the most appropriate diagnostic tools for the suspected pathogen. A total of 97 native stool samples from 95 patients with suspected gastrointestinal illness were analyzed, including 26 from a frozen collection and 71 prospectively collected samples. The diagnostic performance of SA was notably superior to the conventional workflow in detecting Dientamoeba fragilis (sensitivity 100% vs. 47.4%) and Blastocystis hominis (sensitivity 95% vs. 77.5%). SA had a comparable performance with the conventional workflow in detecting pathogenic protozoa (sensitivity 90% vs. 95%). In contrast, SA had a much lower diagnostic performance in detecting helminths (59.1%) compared to the conventional workflow (100%). We conclude that the Seegene Allplex GI-Parasite assay may be useful for protozoa screening in low-endemic industrialized countries. However, the Allplex GI-Helminth assay is not recommended due to its suboptimal performance compared to microscopy.

Prevalence and distribution of intestinal parasitic infections in taeniasis endemic area of North Sumatera, Indonesia.

A group of helminthic and intestinal protozoa causes intestinal parasitic infections (IPIs), affecting more than 2.5 billion people worldwide. IPIs are diseases closely associated with poor hygiene and sanitation, concentrated in underdeveloped regions and among populations with low socioeconomic status. Consequently, most prevalence is in Sub-Saharan Africa and Asia, with local habits or risk factors that could affect its prevalence. The aim of this study was to determine how hygienic practices, sanitation, and local behavior of eating raw meat (hinasumba) contributed to the prevalence of IPI. A cross-sectional study was conducted in the Simalungun District of North Sumatera Province, involving 428 people of Batak Simalungun. There were 15 villages randomly selected across the district based on the local registry, which consequently, non-purposive sampling was conducted. Face-to-face interviews assessed various risk factors, such as demographic characteristics, water source, traditional raw meat consumption, or hinasumba as local risk factors, hygienic practices, and sanitation. The findings indicated that an overall prevalence rate of IPI was 42.9%, consisting of 87.5% with helminthic infection and 12.5% with protozoal infection. More than half of IPI cases were associated with Taenia sp. infections (21.8%), followed by hookworms' infections with a 6.1% positivity rate. Based on multivariate analysis, farming and consuming traditional delicacies, namely hinasumba, increased the likelihood of IPI occurrence among the population by 1.7 and 3 times, respectively. It can be concluded that the high prevalence of taeniasis in the study area was associated with local behavior and hinasumba consumption, which may contribute to determining the dominance of specific IPI species.

Investigating the chemical composition, digestion and fermentation of Alternanthera sessilis red plant and its effect on the performance of fattening lambs.

The present experiment was conducted to evaluate the nutritional value of red Alternanthera sessilis for fattening lambs when they were replaced with alfalfa forage. Forty growing lambs with an average weight of 21.12 kg and an age of 5 months were randomly assigned to four experimental treatments. Growth performance, nutrient digestibility, rumen fermentation parameters, protozoa population, blood parameters, and composition of carcass components were evaluated. The results of this experiment showed that the use of Alternanthera sessilis in the diet significantly reduced feed intake, increased the average daily weight gain, and improved the feed conversion ratio compared to the control treatment (P < 0.05). The digestibility of dry matter and protein was significantly increased (P < 0.05), while the digestibility of neutral detergent fiber, acid detergent fiber, and organic matter showed a numerical increase. Diets containing different levels of the Alternanthera sessilis plant did not affect pH, but the increase in the amount of this plant in the diet led to an increase ammonia nitrogen concentration and rumen protozoa population (P < 0.05). The addition of Alternanthera sessilis to the diet significantly reduced the concentration of blood glucose and cholesterol and increased the concentration of blood urea nitrogen (P < 0.05). Except for the weight of the thigh and neck, the effect of experimental treatments on other carcass components was not significant. Overall, the results of this experiment showed that using the Alternanthera sessilis plant in the rations of fattened lambs as a substitute for alfalfa forage not only had no negative effect on the studied parameters but also improved them in some cases. Therefore, Alternanthera sessilis can be used in rations of fattened lambs as a substitute for part of alfalfa forage.

Prevalence of co-infections with Ehrlichia spp. or Theileria spp. in dogs naturally infected with babesiosis in the Eastern Cape province.

BACKGROUND: Canine babesiosis and ehrlichiosis are tick-borne infections of great significance in South Africa. Theileriosis in dogs in South Africa is still poorly understood. Co-infection with multiple tick-borne diseases has been documented and is perceived as a common occurrence in South Africa. OBJECTIVES: The main objective of this study was to determine the prevalence of co-infections with Ehrlichia canis or Theileria equi in dogs with babesiosis in the Eastern Cape province. There is a lack of data on canine tick-borne disease distribution in this region. Possible associations of population characteristics and haematological and biochemistry measures with a co-infection of E. canis or T. equi in these dogs were also investigated. METHOD: The study population included 150 dogs naturally infected with babesiosis that presented to the Mdantsane State Veterinary Clinic between January 2021 and November 2021. Quantitative polymerase chain reaction was used to confirm the Babesia spp. that the dogs were infected with and to identify co-infections. Association with co-infection for the following parameters were evaluated: sex, breed, age, duration of illness, leukocyte count, band neutrophil count, monocyte count, platelet count, ARC, and serum globulin concentration. Positive and negative predictive values of monocytosis, leukopenia, band neutrophilia, thrombocytopenia, and non-regenerative absolute reticulocyte count for co-infection were also calculated. RESULTS: Babesia rossi was identified in 149/150 samples and B. vogeli in only 1/150 samples. A co-infection prevalence of 2.0% (3/149; 95% CI: 0.4-5.7) with B. rossi and E. canis was found. No other co-infections were reported. No investigated variables showed significant associations with co-infections. Monocytosis, in particular, was not associated with co-infection. CONCLUSION: Co-infection with other tick-borne diseases in dogs with babesiosis is uncommon in the Eastern Cape province. These findings raise the possibility that B. rossi may have a protective effect against other tick-borne diseases.

Feasibility of implementing RPA coupled with CRISPR-Cas12a (RPA-Cas12a) for Hepatozoon canis detection in dogs.

Hepatozoonosis, caused by the protozoan Hepatozoon canis, is a prevalent blood disease affecting owned and stray dogs and cats. The prevalence of these parasites among companion animals in Thailand remains poorly understood. Diagnosing the old-world form of the disease is challenging due to the wide range of nonspecific clinical signs and the reliance on finding low levels of Hepatozoon gamonts in blood smears for conventional diagnosis. PCR demonstrates high specificity and sensitivity but it requires sophisticated instrumentation. Therefore, we established recombinase polymerase amplification (RPA) coupled with Cas12a for H. canis detection based on 18S rRNA. Our findings showed that RPA-Cas12a using gRNA_H was highly specific to H. canis, without yielding positives for other pathogen species including Babesia species. Even in cases of co-infection, RPA-Cas12a only detected positives in samples containing H. canis. This approach detected minimal amounts of H. canis18S rRNA-harboring plasmid at 10 copies per reaction, whereas plasmid-spiked canine blood enabled detection at a minimal amount of 100 copies per reaction. The performance of RPA-Cas12a was validated by comparing it with quantitative PCR-high resolution melting analysis (qPCR-HRM) and sequencing based on 35 canine blood samples. RPA-Cas12a demonstrated precision and accuracy values of 94 % and 90 %, respectively comparable to qPCR-HRM. Overall, these results indicate that RPA-Cas12a serves as a promising tool for H. canis detection as indicated by comparable performance to qPCR-HRM and is suitable for implementation in small animal hospitals or clinics due to its minimal resource requirements, thereby contributing to effective diagnosis and treatment for infected dogs.

The Pathology of the Brain Eating Amoeba Naegleria fowleri.

The genus Naegleria is a taxonomic subfamily consisting of 47 free-living amoebae. The genus can be found in warm aqueous or soil habitats worldwide. The species Naegleria fowleri is probably the best-known species of this genus. As a facultative parasite, the protist is not dependent on hosts to complete its life cycle. However, it can infect humans by entering the nose during water contact, such as swimming, and travel along the olfactory nerve to the brain. There it causes a purulent meningitis (primary amoebic meningoencephalitis or PAME). Symptoms are severe and death usually occurs within the first week. PAME is a frightening infectious disease for which there is neither a proven cure nor a vaccine. In order to contain the disease and give patients any chance to survival, action must be taken quickly. A rapid diagnosis is therefore crucial. PAME is diagnosed by the detection of amoebae in the liquor and later in the cerebrospinal fluid. For this purpose, CSF samples are cultured and stained and finally examined microscopically. Molecular techniques such as PCR or ELISA support the microscopic analysis and secure the diagnosis.

Ac-HSP20 regulates autophagy and promotes the encystation of Acanthamoeba castellanii by inhibiting the PI3K/AKT/mTOR signaling pathway.

BACKGROUND: The encystation of Acanthamoeba castellanii has important ecological and medical significance. Blocking encystation is the key to preventing transmission and curing infections caused by A. castellanii. The formation of autophagosomes is one of the most important changes that occur during the encystation of Acanthamoeba. Our previous studies have shown that the heat shock protein 20 of A. castellanii (Ac-HSP20) is involved in its encystation. This study aimed to determine the role and mechanism of Ac-HSP20 in regulating autophagy involved in the encystation of A. castellanii. METHODS: Immunofluorescence assay, western blotting and transmission electron microscopy were used to analyze the dynamic changes in autophagy during the initiation and continuation of encystation. The knockdown of Ac-HSP20 was performed to clarify its regulation of encystation and autophagy and to elucidate the molecular mechanism by which Ac-HSP20 participates in autophagy to promote cyst maturation. RESULTS: The encystation rates and autophagosomes were significantly decreased by treatment with the autophagy inhibitor 3-MA. The autophagy marker LC3B and autophagic lysosomes increased with the induced duration of encystation and reached the maximum at 48 h. The encystation rate, LC3B expression and autophagosomes decreased when Ac-HSP20 was knocked down by siRNA transfection. In addition, the expression levels of Ac-HSP20 and LC3B increased and the expressions of p-AKT and p-mTOR decreased after 48 h of encystation without knockdown. However, the expressions of p-AKT and p-mTOR increased while the expression of LC3B decreased under the knockdown of Ac-HSP20. Furthermore, the protein expression of LC3B increased when the PI3K/AKT/mTOR signaling pathway was inhibited but decreased when the pathway was activated. CONCLUSIONS: The results demonstrated that autophagy is positively correlated with the encystation of A. castellanii, and Ac-HSP20 regulates autophagy to maintain the homeostasis of A. castellanii by inhibiting the PI3K /AKT /mTOR signaling pathway, thus promoting the maturation and stability of encystation.

Micro-/nano-plastics as vectors of heavy metals and stress response of ciliates using transcriptomic and metabolomic analyses.

The escalating presence of microplastics and heavy metals in marine environments significantly jeopardizes ecological stability and human health. Despite this, research on the combined effects of microplastics/nanoplastics (MPs/NPs) and heavy metals on marine organisms remains limited. This study evaluated the impact of two sizes of polystyrene beads (approximately 2 µm and 200 nm) combined with cadmium (Cd) on the ciliate species Euplotes vannus. Results demonstrated that co-exposure of MPs/NPs and Cd markedly elevated reactive oxygen species (ROS) levels in ciliates while impairing antioxidant enzyme activities, thus enhancing oxidative damage and significantly reducing carbon biomass in ciliates. Transcriptomic profiling indicated that co-exposure of MPs/NPs and Cd potentially caused severe DNA damage and protein oxidation, as evidenced by numerous differentially expressed genes (DEGs) associated with mismatch repair, DNA replication, and proteasome function. Integrated transcriptomic and metabolomic analysis revealed that DEGs and differentially accumulated metabolites (DAMs) were significantly enriched in the TCA cycle, glycolysis, tryptophan metabolism, and glutathione metabolism. This suggests that co-exposure of MPs/NPs and Cd may reduce ciliate abundance and carbon biomass by inhibiting energy metabolism and antioxidant pathways. Additionally, compared to MPs, the co-exposure of NPs and Cd exhibited more severe negative effects due to the larger specific surface area of NPs, which can carry more Cd. These findings provide novel insights into the toxic effects of MPs/NPs and heavy metals on protozoan ciliates, offering foundational data for assessing the ecological risks of heavy metals exacerbated by MPs/NPs.

Acanthamoeba castellanii alone is not a growth promoter for Hordeum vulgare.

Protists are important key players in the microbial loop and influence their environment by grazing, which leads to the return of nutrients into the soil and reduces pathogen pressure on plants. Specifically, protists on and around plant roots are important for plants' development and growth. For this study, the fourth most important crop in the world, Hordeum vulgare, was selected. Seeds of H. vulgare were inoculated with Acanthamoeba castellanii alone or with additional soil bacteria at the beginning and during the experiment. The germination of the seeds and the growth of the plants in pouches were monitored over 3 weeks. No differences were found in leaf growth, root growth, root and leaf nitrogen content or ammonia content of the liquid from the pouches. In contrast, the relative increase in root and leaf dry weight showed a small difference compared to the controls. The results of this experiment demonstrated that seed inoculation with A. castellanii alone or with additional unidentified soil bacteria did not have a major effect on the growth and development of barley. Nevertheless, small changes in plant development were detected, indicating that A. castellanii should be considered for further investigation of co-inoculations with plant growth-promoting bacteria and additional nutrients.

Feed efficiency and enteric methane emissions indices are inconsistent with the outcomes of the rumen microbiome composition.

The correlation between enteric methane emissions (eME) and feed efficiency (FE) in cattle is linked to the anaerobic fermentation of feedstuffs that occurs in the rumen. Several mathematical indices have been developed to predict feed efficiency and identify low methane emitters in herds. To investigate this, the current study aimed to evaluate the rumen microbial composition in the same group of animals ranked according to six different indices (three indices for FE and three for eME). Thirty-three heifers were ranked into three groups, each consisting of 11 animals, based on FE (feed conversion efficiency - FCE, residual weight gain - RG, and residual feed intake - RFI) and eME indices (production, yield, and intensity). Rumen fluids were collected using a stomach tube and analyzed using 16S rRNA and 18S rRNA, targeting rumen bacteria, archaea, and protozoa. The sequencing analysis revealed that the presence of unique microbial species in the rumen varies across animals ranked by the FE and eME indices. The High RG group harbored 17 unique prokaryotic taxa, while the High FCE group contained only seven. Significant differences existed in the microbial profiles of the animals based on the FE and eME indices. For instance, Raoultibacter was more abundant in the Intermediate RFI group but less so in the Intermediate RG and Intermediate FCE groups. The abundance of Entodinium was higher while Diplodinium was lower in the High FCE group, in contrast to the High RG and High RFI groups. Methanobrevibacter exhibited similar abundances across eME indices. However, the heifers did not demonstrate the same production, yield, and intensity of eME. The present findings underscore the importance of standardizing the FE and eME indices. This standardization is crucial for ensuring consistent and reliable assessments of the composition and function of the rumen microbiome across different herds.

Molecular evaluation of Eimeria spp. Infection in the Volga-Ural Saiga antelope population of the Republic of Kazakhstan.

Saiga antelope (Saiga tatarica) is a protected species in Kazakhstan. Little is known about the parasitofauna of these mammals. Therefore, the focus of this study was to evaluate the prevalence and species diversity of Eimeria spp. infection in the Volga-Ural Saiga antelope population. In June 2023, 104 Saiga antelope fecal samples collected from the district of Zhanibek, located in the province of West Kazakhstan were evaluated using microscopic and molecular techniques. Based on coprovoscopy results, Eimeria spp. Oocysts were present in 22 samples (21%). The four fecal samples containing the largest numbers of Eimeria spp. Oocysts per 10x field were selected for further genetic analysis. DNA extraction, nested PCR amplification, and sequencing were performed on 91 clones, with 80 clones forming a distinct clade and exhibiting genetic similarity to MT801034 Eimeria sp. Voucher HY3. These clones possibly represent an Eimeria specific to Saiga antelopes and gazelle that has previously been morphologically described as Eimeria elegans (Svanbaev, 1979), underscoring the importance of further research into parasitic infections in this protected species.

Protozoan Infections in Cancer Patients: A Case Series.

Intestinal parasitic infections can cause significant morbidity and mortality in individuals with cancer. Despite this, they are often self-limiting in healthy individuals. Entamoeba histolytica is an anaerobic parasite that causes amebiasis in infected individuals. Poor sanitary conditions and endemic areas increase the risk of contracting amebiasis. Furthermore, giardiasis is a parasitic infection of the small intestine that is caused by Giardia duodenalis, a flagellated protozoan. In both cases, the disease burden is greater and the timeline is longer among immunosuppressed patients. Due to this, we aimed to more thoroughly characterize disease progression and treatment efficacy of these intestinal parasitic infections in cancer patients by presenting a case of intestinal amebiasis and enterocolitis due to Entamoeba histolytica, as well as two giardiasis cases, while also providing a review of the literature.