Genetic diversity and seroprevalence of Toxoplasma gondii in COVID­19 patients; a first case-control study in Iran.

BACKGROUND: Toxoplasmosis is a serious or life-threatening disease in immunosuppressed patients and pregnant women. This study examined the likely association between Toxoplasma gondii infection and COVID-19 patients with moderate illness. METHODS: Seventy blood samples were collected from patients at the Health Reference Laboratory of Tabriz, Northwest Iran from April 2021 to September 2021. In addition, 70 healthy subjects of the same age (37 ± 15 years) and sex distribution were ethnically matched. Sera samples were examined for the detection of anti-Toxoplasma antibodies using ELISA. Nested-PCR targets were amplified based on the B1 and GRA6 genes. GRA6 amplicons were subjected to sequencing and phylogenetic analysis. RESULTS: The seroprevalence of toxoplasmosis based on IgG titer was 35.7% in the COVID­19 patients and 27.1% in the control group, representing not to be associated with the Toxoplasma seropositivity in COVID­19 patients (P = 0.18) compared to healthy subjects. Anti-T. gondii IgM was not found in any of the patients and healthy individuals. According to PCR amplification of the B1 and GRA6 genes, the frequency of T. gondii in COVID-19 patients was 14.2% (10/70). However, no T. gondii infection was detected in the healthy group. The CD4+T cell count was relatively lower in toxoplasmosis-infected patients (430-450 cells/mm3) than in control group (500-1500 cells/mm3). High genetic diversity (Hd: 0.710) of the type I strain of T. gondii was characterized in the patients. Present results showed that consumption of raw vegetables and close contact with stray cats can increase the transmission of T. gondii to COVID-19 patients (P < 0.01). CONCLUSIONS: The current study revealed that T. gondii type I infection is unequivocally circulating among the COVID-19 patients in Tabriz; However, no significant association was observed between the occurrence of Toxoplasma and the severity of COVID-19. To make more accurate health decisions, multicenter investigations with a larger sample size of different ethnic groups of the Iranian population are needed.

Global haplotype distribution of Babesia ovis inferred by 18S rRNA sequences; a phylogeographical systematic review.

The genetic variability of apicomplexan parasite Babesia species is a principal strategy used by piroplasma to evade their hosts' immune responses. The purpose of this review was to evaluate our current knowledge on global haplotype distribution and phylogeography of Babesia ovis derived from sheep, goat, horse and ixodid (hard) ticks. Bibliographic English databases were searched from 2017 to 2023, identifying a total of 11 publications. The 18S ribosomal RNA (18S rRNA) sequences of B. ovis from Asia, Europe, and Africa were retrieved and subjected to estimate the genetic diversity and phylogenetic assessment. A haplotype network indicated a total of 29 haplotypes being classified into two distinct geographical haplogroups I and II including Nigeria and Uganda-derived B. ovis isolates. A moderately high level of genetic diversity was characterized in sheep/tick-derived B. ovis isolates originating from Iraq (Haplotype diversity: 0.781) and Turkey (Hd: 0.841). Based on the cladistic phylogenetic tree, two geographically different lineages of A and B were genetically differentiated except for Turkish isolates, indicating haplotype migration occurred between various geographical clades. In addition, the topology of UPGMA tree indicated that B. ovis population has a distinct clade compared to the rest clades of ovine babesiosis (B. crassa and B. motasi). The present results strengthen our knowledge to evaluate the evolutionary paradigms and transmission dynamics of B. ovis in different regions of the world; also it will provide groundwork for public health policy to control ovine babesiosis.

Molecular diagnosis, phylogenetic analysis, and antifungal susceptibility profiles of Candida species isolated from neutropenic oncological patients.

BACKGROUND: Neutropenia is the most important cause of life-threatening invasive fungal infections (IFIs). Here, we studied the frequency and antifungal susceptibility profiles of Candida species that colonized or caused infections among neutropenic patients with solid or hematological malignancies. METHODS: A total of 362 clinical samples were collected from 138 patients. After initial isolation using a mix of mycological methods, isolates were screened using chromogenic culture media. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was applied for molecular identification. Positive or suspected cases were confirmed using the reference method of sequencing. Antifungal susceptibility testing for voriconazole and caspofungin was carried out using the microbroth dilution method. An in-silico assay was applied for phylogenetic analysis. RESULTS: Thirty-four Candida strains were isolated. C. albicans (47.06%) and C. glabrata (29.41%) were the most frequent strains. Antifungal treatment reduced the chance of Candida colonization by almost 76% in neutropenic patients (OR: 1.759; 95% CI: 1.349 to 2.390; p value: 0.000). An unusual and non-resistant strain, C. lambica, was reported from the bloodstream of a 56-year-old man with hematologic malignancy (HM). Eight isolates were non-susceptible, and one isolate was resistant to voriconazole. Also, four isolates were non-susceptible to caspofungin. CONCLUSION: We can conclude that there is a cause-and-effect relationship between neutropenia, HM background, and Candida species separated from neutropenic patients, which can lead to possible infections. Further and repetitive studies are recommended using different molecular methods for better prediction and management of fungal infections in neutropenic patients.

In vitro and ex vivo protoscolicidal effects of hydroalcoholic extracts of Eucalyptus microtheca on protoscoleces of Echinococcus granulosus sensu stricto: A light and scanning electron microscopy (SEM) study.

BACKGROUND: Cystic echinococcosis (CE) is one of the most widespread and important global helminth zoonoses. Treatment relies mainly on surgery and, or percutaneous interventions. However, spillage of live protoscoleces (PSCs) leading to recurrence is a problem during surgery. So, the application of protoscolicidal agents before surgery is required. This study aimed to investigate the activity and safety of hydroalcoholic extracts of E. microtheca against PSCs of Echinococcus granulosus sensu stricto (s.s.) both in vitro and also ex vivo, which is a simulation to Puncture, Aspiration, Injection, and Re-aspiration (PAIR) method. METHODS: Considering the effects of heat on the protoscolicidal effecacy of Eucalyptus leaves, hydroalcoholic extraction was performed by both soxhlet extraction at 80 °C and percolation at room temperature. The protoscolicidal action of hydroalcoholic extracts was assessed by in vitro and ex vivo assessments. Infected sheep livers were collected from the slaughterhouse. Then, the genotype of hydatid cysts (HCs) was confirmed by sequencing and, isolates were limited to E. granulosus s.s. In the next step, ultrastructural changes of Eucalyptus-exposed PSCs were studied by scanning electron microscopy (SEM). Finally, a cytotoxicity test was conducted by (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay to evaluate the safety of E. microtheca. RESULTS: The prepared extracts by soxhlet extraction and percolation were, successfully exerted strong protoscolicidal effects in both in vitro and ex vivo tests. The results of in vitro assessment indicated that hydroalcoholic extract of E. microtheca prepared by percolation at room temperature (EMP) and hydroalcoholic extract of E. microtheca prepared by soxhlet extraction at 80 °C (EMS) killed all PSCs (100%) at concentrations of 10 and 12.5 mg/mL, respectively. Also, EMP showed 99% protoscolicidal action after 20 min in an ex vivo setting compared to EMS. SEM micrographs confirmed potent protoscolicidal and destructive effects of E. microtheca against PSCs. The cytotoxicity of EMP was tested on the HeLa cell line using MTT assay. The value of 50% cytotoxic concentration (CC50) was calculated at 46.5 µg/mL after 24h. CONCLUSION: Both hydroalcoholic extracts showed potent protoscolicidal activity and, especially EMP produced remarkable protoscolicidal effects compared to the control group.

Gene migration of giardiasis in Iran; a microevolutionary scale for reflecting transmission patterns of Giardia lamblia assemblages in symptomatic patients.

In the microevolutionary scale of Giardia lamblia, the gene migration indicates how G. lamblia assemblages have transmitted between adjacent counties. 33 positive fecal samples were taken from patients suffering gastrointestinal disorders (nausea, bloating, burping constipation and fatty diarrhea) at Tabriz and Ardabil cities, where located in the cold regions of northwest Iran. Following parasitological examinations, DNA samples were extracted, amplified and digested by single-step PCR-RFLP assay, targeting the glutamate dehydrogenase (gdh) locus to distinguish within and between assemblages A and B. PCR products were directly sequenced to reconfirm their heterogeneity traits and phylogenetic analysis. Of the 33 isolates, 81.9% (n: 27), 9% (n: 3) and 9% (n: 3) were successfully identified as assemblages A (genotype AII), B (genotype BIII) and the mixed of genotypes AII and B, respectively. Despite the presence of heterogeneous clinical backgrounds, a low genetic diversity of sub-assemblage AII was identified among symptomatic cases. A low value of pairwise fixation index showed that G. lamblia sub-assemblage AII is not genetically differentiated among northwest regions of Iran. The occurrence of haplotypes TAB-1/ARD-1 between two regional populations indicates that there is a dawn of G. lamblia gene flow due to transfer of alleles through host mobility and/or ecological alterations. To assess the hypothetical evolutionary scenario, further studies are essential for multilocus genotyping of G. lamblia in tropical regions of Iran and neighboring countries.

In vitro efficacy of albendazole-loaded ß-cyclodextrin against protoscoleces of Echinococcus granulosus sensu stricto.

BACKGROUND: Cystic echinococcosis (CE), a widespread helminthic disease caused by the larval stage of the dog tapeworm Echinococcus granulosus represents a public health concern in humans. Albendazole (ABZ) is the first-line treatment for CE; however therapeutic failure of ABZ against CE occurs because of size and location of formed cysts as well its low aqueous solubility and consequently its erratic bioavailability in plasma. Serious adverse effects have also been observed following the long-term use of ABZ in vivo. METHODS: We evaluated the apoptotic effects of ABZ-loaded ß-cyclodextrin (ABZ-ß-CD) against protoscoleces (PSCs) versus ABZ alone. After 15 h of exposure, Caspase-3 enzymatic activity was determined by fluorometric assay in PSCs treated with ABZ and ABZ-ß-CD groups. To assess the treatment efficacy of ABZ-ß-CD against PSCs, mRNA expression of Arginase (EgArg) and Thioredoxin peroxidase (EgTPx) were quantified by Real-time PCR. RESULTS: A significant scolicidal activity of ABZ was observed only at a concentration of 800 µg/mL (100% PSCs mortality rate after 4 days of exposure), while the 200 and 400 µg/mL ABZ reached 100% PSCs mortality rate after 9 sequential days. The 400 µg/mL ABZ-ß-CD had 100% scolicidal rate after 5 days of exposure. Morphological alterations using scanning electron microscopy in treated PSCs revealed that 400 µg/mL ABZ-ß-CD induced higher Caspase-3 activity than their controls, indicating a more potent apoptotic outcome on the PSCs. Also, we showed that the 400 µg/mL ABZ-ß-CD can down-regulate the mRNA expression of EgArg and EgTPx, indicating more potent interference with growth and antioxidant properties of PSCs. CONCLUSIONS: In the present study, a significant scolicidal rate, apoptosis intensity and treatment efficacy was observed in PSCs treated with 400 µg/mL ABZ-ß-CD compared to ABZ alone. This provides new insights into the use of nanostructured ß-CD carriers with ABZ as a promising candidate to improve the treatment of CE in in vivo models.

Expression analysis of circulating miR-146a and miR-155 as novel biomarkers related to effective immune responses in human cystic echinococcosis.

Cystic echinococcosis, an important zoonotic disease, is caused by Echinococcus granulosus. MicroRNAs are a small group of single-stranded noncoding RNAs, which play an effective role in biological processes. This study aimed at comparing the expression levels of miR-146a and miR-155 in the plasma of patients with hydatidosis and healthy individuals. A group of 20 patients with hydatid cyst formed a study group and 20 healthy individuals with no known chronic diseases formed a control group. Plasma samples were collected from hydatidosis patients as well as sex- and age-matched healthy volunteers. After that, RNA extraction and cDNA synthesis were done and the expression levels of miR-146a and miR-155 were determined by quantitative real-time polymerase chain reaction (PCR) for both groups. The results indicated that the level of miR-146a increased in all patients with hydatidosis compared to the control group. Also, the level of miR-155 increased in all hydatidosis patients, but no correlation was observed in the level of miR-155 between the two groups. The results also revealed that miR-146a and miR-155 upregulation in the plasma leads to the development of novel biomarkers for echinococcosis. One of the reasons for the increase of miRNAs in hydatidosis may be their role in modulating the immune system. These miRNAs are likely to be considered as one of the most important biomarkers in determining the severity of hydatidosis.

MicroRNA-365 promotes apoptosis in human melanoma cell A375 treated with hydatid cyst fluid of Echinococcus granulosus sensu stricto.

Hydatid cyst fluid (HCF)-based therapeutics has experimentally targeted approaches for treating human cancer cell lines. MicroRNA-365 (miR-365) has been reported to be an important tumor suppressor miRNA in cancers. However, it remains unknown, how miR-365 plays a pivotal role in inducing apoptosis in HCF-treated cancer cells in vitro. The fertile/infertile HCF was aspirated from liver of infected sheep and in terms of molecular taxonomy was identified as G1 genotype of Echinococcus granulosus sensu stricto. A375 human melanoma cancer cells were cultured into two groups: fertile and infertile HCF-treated A375 cells. To assess the cytotoxicity of various concentrations of HCF on melanoma cells, cell viability was determined by using MTT assay. The IC50 value of HCF on A375 cells was determined 85 µg/mL. Caspase-3 enzymatic activity was evaluated by fluorometric assay in the HCF-treated melanoma cells. In addition, the mRNA expression of Bax, Bcl-2, Caspase-9 and miR-365 were determined by qRT-PCR. Findings of MTT assay showed that concentrations 85 µg/mL to 100 µg/mL of fertile HCF have the highest mortality (50%-52%) on A375 cells during 24 h. The fold change of Bax/Bcl-2 ratio, Caspase-9, miR-365 and Caspase-3 activity was higher in the fertile HCF-treated melanoma cells compared to infertile fluid treated A375 cells and human normal epithelial cell (as control cell). In conclusion, we over-expressed the miR-365 in melanoma A375 cells, via treatment of fertile HCF. Our findings suggested that inducing high expression of miR-365 might be a negative regulator of melanoma growth through activation of pro-apoptotic Bax, Caspase-9 and Caspase-3 that are essential to intrinsic apoptotic pathway. These findings provide new insights into the use of Echinococcus HCF-derived metabolites in the design of drug therapies and in vivo tumor cell vaccine to combat melanoma progression.

The global status and genetic characterization of hydatidosis in camels (Camelus dromedarius): a systematic literature review with meta-analysis based on published papers.

Hydatidosis is a potential zoonotic helminthic disease affecting a broad spectrum of mammals, including humans, worldwide. The current review was conducted to investigate the genotypic status and prevalence of hydatid disease in camels across the world. For the purpose of the study, the articles addressing the worldwide prevalence of hydatidosis in camels were searched in several English language databases. The search process resulted in the inclusion of 122 papers. Based on the data presented in the reviewed articles, the pooled prevalence of hydatid disease in camels across the world was measured at 23.75% (95% CI 20.15-27.55). Moreover, the subgroup analysis demonstrated significant differences in the overall prevalence of hydatidosis among camels based on year, geographic area, climate parameters, camel population, gender, infected organ, fertility rate of the cyst and laboratory diagnostic technique. Furthermore, the Echinococcus granulosus genotypes identified in camels with hydatidosis included G1, G2, G3, G1-G3, G5, G6, G7, G6-G7 and G6-G10, with G6 being the most common genotype throughout the world. The data obtained from the current study are central to the better conceptualization of the biological and epidemiological characteristics of E. granulosus s.l. genotypes around the world, which can be helpful in the planning and adoption of more comprehensive control strategies.

The association between seropositivity to human toxocariasis and childhood asthma in northern Iran: a case-control study.

BACKGROUND: Besides the well-known risk factors, Toxocara infection is thought to play a significant etiological role in the development of childhood asthma. To further explore this association, the prevalence of Toxocara infection in sera of asthmatic children and healthy controls in northern Iran was investigated. METHODS: In this case-control study, cases were 145 physician-confirmed asthmatic children diagnosed according to the Global Initiative for Asthma (GINA) guidelines. Controls were 115 age-sex-residence-matched children who did not have physician-diagnosed asthma. The presence of anti-Toxocara immunoglobulin G (IgG) was tested using enzyme-linked immunosorbent assay. Univariate and multivariate logistic regression methods were used for case-control comparisons. RESULTS: Seropositivity rate was 4.1% (95% CI, 3.4-4.7%) in asthmatic children and 0.86% (95% CI, 0.71-1.0%) in controls, suggesting a strong association (P-value < 0.02). Moreover, Toxocara infection was not significantly more prevalent (P-value = 0.12) in children with moderate sustainable asthma (9.3%, 3/32) than in children with mild sustainable asthma (2.3%, 3/113). Mean total immunoglobulin E (IgE) level was significantly higher in Toxocara-infected children (222.3 ± 367.1) than in non-infected children (143.19 ± 218.05) in the case group (P-value < 0.05). CONCLUSIONS: Our findings indicated that Toxocara infection can play an important role in childhood asthma. Further experimental and epidemiological studies are needed to clarify this hypothesis.

The prevalence of latent and acute toxoplasmosis in HIV-infected pregnant women: A systematic review and meta-analysis.

OBJECTIVE: HIV in pregnancy is not only important for mother-to-child HIV transmission, but also it assumes additional importance because HIV increases susceptibility to opportunistic infections, leading to increased morbidity and mortality in mothers and neonates. Toxoplasmosis is one of the most important opportunistic infections in HIV-infected pregnant women. The present study was undertaken to assess the prevalence of latent toxoplasmosis (LT) and acute toxoplasmosis (AT) infection in HIV-infected pregnant women. METHODS: PubMed/MEDLINE, Scopus, Web of Science, EMBASE and SciELO were searched to identify relevant studies. A random-effects model was used to estimate the overall and subgroup-pooled prevalences across studies. Heterogeneity between studies was assessed via the I2 test. RESULTS: A total of 14 articles that included 3256 subjects in nine countries met the inclusion criteria. The overall prevalence rates of LT and AT in HIV-infected pregnant women were 45.7% (95% CI, 32.3-59.7%) and 1.1% (95% CI, 0.4-3.2%), respectively. The findings indicate that, worldwide, approximately 559,000 and 13,450 HIV-infected pregnant women are affected by LT and AT, respectively. From this review, it is estimated that approximately 3432 babies annually could be born with congenital toxoplasmosis (CT) from HIV-infected pregnant mothers. CONCLUSIONS: The present study indicates that a large number of HIV-infected mothers are affected by LT and AT. This can lead to adverse complications such toxoplasmic encephalitis in mothers and CT in neonates. Our results suggest a need for screening programs using well-validated diagnostic platforms for both LT and AT for all HIV-infected pregnant women.

Morphometric, genetic diversity and phylogenetic analysis of Taenia hydatigena (Pallas, 1766) larval stage in Iranian livestock.

Cysticercus tenuicollis as metacestode of Taenia hydatigena is the most prevalent taeniid species in livestock. Eighty-eight C. tenuicollis samples were collected from sheep (n = 44) and goats (n = 44) of the northern Iran from 2015 to 2016. The isolated parasites were characterized by morphometric keys. The DNA of the larval stage was extracted, amplified and sequenced targeting mitochondrial 12S rRNA and Cox 1 markers. A significant difference in larval rostellar hook length was observed in 12S rRNA haplotypes. Analysis of molecular variance of 12S rRNA indicated a moderate genetic diversity in the C. tenuicollis isolates. The pairwise sequence distance of C. tenuicollis showed an intra-species diversity of 0.3-0.5% and identity of 99.5-100%. Using the 12S rRNA sequence data we found a moderate genetic difference (Fst; 0.05421) in C. tenucollis isolates collected from livestock of the northern and southeastern regions of Iran. We concluded that the genetic variants of C. tenuicollis are being undoubtedly distributing mostly in different parts of Iran. Further studies with a larger number of T. hydatigena isolates collected from various intermediate and definitive hosts are needed to study this evolutionary assumption and also to determine the apparent genetic differences observed in the studied regions.

IL-17 and IL-22 elicited by a DNA vaccine encoding ROP13 associated with protection against Toxoplasma gondii in BALB/c mice.

Toxoplasma gondii, an intracellular parasitic protozoan, is capable of infecting man and all warm-blooded animals. Cell-mediated immunity is vital in mounting protective responses against T. gondii infection. Recent studies have shown that T-helper (Th) 17 responses may play a key role in parasite control. In this current study, we constructed a DNA vaccine encoding T. gondii ROP13 in a pcDNA vector. Groups of BALB/c mice were immunized intramuscularly with pcROP13 or controls and challenged with the RH strain of T. gondii. The results showed that immunization with pcROP13 could elicit an antibody response against T. gondii. The expression of the canonical Th17 cytokines, interleukin (IL)-17 and IL-22, were significantly increased after immunization with pcROP13 compared with control groups ( p < 0.05). Furthermore, vaccination resulted in a significant decrease in parasite load ( p < 0.05). The induction of Th17 related cytokines, using a ROP13 DNA vaccine, against T. gondii should be considered as a potential vaccine approach for the control of toxoplasmosis.

Ophthalmomyiasis Caused by Chrysomya bezziana after Periocular Carcinoma.

We treated a homeless man in Iran with a history of squamous cell carcinoma who had ophthalmomyiasis caused by Chrysomya bezziana parasites. This case highlights a much-neglected condition and describes measures to prevent it.

Candidate antigenic epitopes for vaccination and diagnosis strategies of Toxoplasma gondii infection: A review.

Toxoplasmosis caused by an obligatory intracellular protozoan parasite of Toxoplasma gondii threats a wide spectrum of human and animal hosts. It has been shown that the intensity of the disease in humans depends on the host's immune responses. Immunological investigations on whole protein molecules of T. gondii have shown that these antigens are not fully responsible for the immune response, which leads to a decrease in specificity and affinity of the antigen (epitope)-antibody (paratope) binding. Currently, epitopes have shown promising entities to stimulate B, T, cytotoxic T lymphocyte, and NK cells resulting in enhancement of protective immunity against toxoplasmosis patients. Thus, the accurate designing, prediction, and conducting of antigenic epitopes of T. gondii (with linear and/or spatial structures (can augment our understanding about development of new serological diagnostic kits and vaccines. The current review provides an update on the latest advances of current epitopes described against toxoplasmosis including B cell/T cell epitopes, antigen types, parasite strains, epitope sequences, assay settings (in vitro and/or in vivo), and target strategy. Present results disclosed that the designing of effective multiepitopes of T. gondii by in silico modeling and immunoinformatics tools can strengthen our knowledge about triggering of epitope-based vaccine/diagnosis strategies in future perspectives.

Laboratory Cross-Contamination of Mycobacterium tuberculosis: A Systematic Review and Meta-analysis.

BACKGROUND: Microbiological cultures are the mainstay of the diagnosis of tuberculosis (TB). False-positive TB results lead to significant unnecessary therapeutic and economic burden and are frequently caused by laboratory cross-contamination. The aim of this meta-analysis was to quantify the prevalence of laboratory cross-contamination. METHODS: Through a systematic review of five electronic databases, we identified studies reporting rates of laboratory cross-contamination, confirmed by molecular techniques in TB cultures. We evaluated the quality of the identified studies using the National Institute of Health (NIH) Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies, and conducted a meta-analysis using standard methodology recommended by the Cochrane Collaboration. RESULTS: Based on 31 eligible studies evaluating 29,839 TB cultures, we found that 2% (95% confidence intervals [CI] 1-2%) of all positive TB cultures represent false-positive results secondary to laboratory cross-contamination. More importantly, we evaluated the rate of laboratory cross-contamination in cases where a single-positive TB culture was available in addition to at least one negative TB culture, and we found a rate of 15% (95% CI 6-33%). Moreover, 9.2% (91/990) of all patients with a preliminary diagnosis of TB had false-positive results and received unnecessary and potentially harmful treatments. CONCLUSIONS: Our results highlight a remarkably high prevalence of false-positive TB results as a result of laboratory cross-contamination, especially in single-positive TB cultures, leading to the administration of unnecessary, harmful treatments. The need for the adoption of strict technical standards for mycobacterial cultures cannot be overstated.

Isolation, identification, and phylogenetic analysis of potentially pathogenic free-living amoebae isolated from nasal and oral mucosa of HIV/AIDS patients in Iran.

The burden of HIV/AIDS in Iran is not as high as in the other countries with high prevalence; however, the number of cases of HIV/AIDs is increasing in this region. According to a recent report, Iran had 5000 (1400-13,000) new cases of HIV infection with 4000 (2500-6200) AIDS-related deaths. Individuals affected by HIV/AIDS are highly susceptible for developing opportunistic infections, e.g. the cerebral complications related to pathogenic free-living amoebae and colonization of free-living amoebae (FLA) can be a serious hazard for patients living with HIV/AIDS. In the present study, a total of 70 oral and nasal mucosal samples were obtained from HIV/AIDS patients referred to the reference hospitals in Iran and tested for the presence of potentially pathogenic FLA using culture and PCR/sequencing-based methods. To discern the taxonomic status of Acanthamoeba genotypes a maximum likelihood phylogenetic tree was constructed and tolerance assays were performed for the positive Acanthamoeba strains. Among the patients with HIV/AIDS referred to the reference hospitals from 2017 to 2019, 7.1% were found positive for pathogenic free-living amoebae. Three strains (HA3, HA4, and HA5) belonged to the T4 genotype, one strain (HA1) was related to the T5 genotype assigned as A. lenticulata, and another strain (HA2) had high homology to Vermamoeba vermiformis. The tolerance assay used for Acanthamoeba strains (HA1, HA3, and HA4) classified these amoebae as highly pathogenic strains. For the most part, the encephalitis cases occurring in HIV/AIDS patients in Iran remain undiagnosed due to lack of awareness of the practitioners on the available diagnostic tools for this lethal infection; therefore, the true incidence of GAE in this region is unknown. A possible colonization with FLA should be considered in the differential diagnosis of suspected cases of CNS infections among HIV/AIDS patients. This study is the first worldwide comprehensive study attempting to isolate and identify the FLA colonization in HIV/AIDS patients. This study highlights the fact that clinicians should be aware of the differential diagnosis of cerebral disease related to FLA in patients with HIV/AIDS.

Therapeutic efficacy of nanocompounds in the treatment of cystic and alveolar echinococcoses: challenges and future prospects.

Echinococcus granulosus sensu lato and E. multilocularis are the causative agents of life-threatening cystic and alveolar echinococcoses (CE and AE), respectively, which lead to serious public health concerns across the globe. Benzimidazoles (BMZs) are the drugs of choice for the treatment of human CE and AE. Presently, the chemotherapeutic failures of BMZs against CE and AE are caused by their low aqueous solubility, poor absorption, and consequently their erratic bioavailability. Among the BMZ compounds used for CE/AE treatment, albendazole (ABZ) and mebendazole (MBZ) are the only drugs licensed for human use. Nevertheless, the administration of these BMZs for a long period of time leads to undesirable adverse effects. Therefore, there is an urgent need for designing new formulations of BMZs with increased bioavailability. To bridge these therapeutic gaps, nanoparticle enantiomers of ABZ and drug delivery systems based on nanostructured entities currently provide an interesting new formulation of already existing drugs to improve the pharmacokinetic effects of BMZs. This study provides an overview of the tested nanocompounds against E. granulosus and E. multilocularis, including their effective dose, type of nanoparticles (NPs), assay setting, and therapeutic outcomes. This review suggests that BMZ derivatives loaded in NPs can significantly improve the scolicidal and cysticidal activities compared with single BMZ. Moreover, BMZ-loaded polymeric NPs show a tendency to increase mortality rate against protoscoleces and microcysts compared with metallic formulations, nanoemulsions, lipid nanocapsules, solid lipid NPs, liposomes, and nanocrystals. In the future, the use of the newly structured entities, attained by bridging ligands to the modified surface of NPs, as well as the electromagnetically produced nanodrugs could be helpful for developing fine-tuned formulations as an alternative to the already existing drugs against these neglected parasitic infections.

Amoebiasis in Iran: a systematic review and meta-analysis.

A comprehensive meta-analysis study was performed to estimate the reliable national prevalence and molecular epidemiology of amoebiasis in Iran. Nine English and Persian databases were searched to achieve the relevant studies. Pooled estimates were generated and meta-regression was performed. We identified 71 eligible articles involving 330 930 subjects from 25 provinces to be included in the final analysis. Moreover, 17 studies compromising 462 polymerase chain reaction (PCR)-positive isolates performed molecular analysis to inter-species differentiation. The pooled prevalence of Entamoeba infection among Iranian population was about 1% (95% CI 0.8-2.0%). Moreover, regarding Human Development Index (HDI), a higher prevalence was observed in undeveloped provinces. Out of 462 PCR-positive isolates, 83% (95% CI 69-94%) and 12% (95% CI 3-24%) were Entamoeba dispar, Entamoeba histolytica, respectively. In subgroup analysis based on molecular results, in general, population prevalence of Entamoeba dispar and E. histolytica were 91% (95% CI 80-99%) and 7%, (95% CI 0-19%), respectively, while prevalence of these species in patients with gastrointestinal disorders were 75% (95% CI 45-96%) and 18% (95% CI 1-43%), respectively. Our findings indicate the low burden of amoebiasis in Iran. E. dispar, that is mostly non-pathogenic, was identified as most prevalent species. Nevertheless, we suggest more public health interventions in areas with lower HDI.