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The aims were to investigate the clinical characteristics of Toxoplasma gondii (T. gondii) immunoglobulin (Ig) M-positive mothers and to clarify the incidences of serum T. gondii IgM or blood T. gondii DNA positivity in newborns born to the mothers and the actual congenital T. gondii infection. Mothers with T. gondii IgM positivity and newborns born to the mothers from 2013 to 2020 were prospectively investigated. Serum T. gondii IgG and IgM were measured by enzyme-linked immunosorbent assay. Blood T. gondii DNA was detected by semi-nested polymerase chain reaction. Congenital T. gondii infection was diagnosed based on clinical characteristic manifestations with serum T. gondii IgG positivity at any age or T. gondii IgG positivity after 12 months of age. Among 71 T. gondii IgM-positive mothers, including one with triplets, 41% had low T. gondii IgG avidity index and 73% received maternal therapy. Among 73 newborns who were examined for serum T. gondii IgG and IgM at birth, none had clinical manifestations, and one (1.4%) had T. gondii IgM positivity. Among 32 newborns who were examined for blood T. gondii DNA at birth, two (6.3%) were positive. All patients with serum T. gondii IgM or blood T. gondii DNA positivity showed T. gondii IgG negativity within 12 months of age. A few newborns born to T. gondii IgM-positive mothers were suspected of having congenital T. gondii infection based on serum T. gondii IgM or blood T. gondii DNA testing at birth. However, none developed congenital T. gondii infection. [ABSTRACT FROM AUTHOR]

BACKGROUND: Children with hematologic malignancies are currently at a severe threat of developing bloodstream fungal infection (BSFI). The early detection of BSFI followed by appropriate management of these patients remains a challenge to the oncologist of today. The conventional method of detection like blood culture followed by identification is time-consuming and of low accuracy. The molecular approaches like polymerase chain reaction (PCR) and its variants like semi-nested PCR (SnPCR) can be an attractive alternative to diagnose early and accurately BSFI but need to be explored. OBJECTIVE: The aim of our study was to determine the utility of SnPCR over conventional blood culture in detecting BSFI in leukemic children with febrile neutropenia. MATERIALS AND METHODS: A total of 53 pediatric patients with febrile neutropenia due to hematological malignancy were included in this study. From each patient, blood sample was collected for conventional blood culture, while SnPCR was performed from the overnight incubated blood broth. The blood culture-positive isolates were further identified to species level using conventional techniques. The PCR products obtained were sequenced and results interpreted after nucleotide BLAST and refinement. RESULTS: Fungal DNA was detected in 13 (24.5%) febrile neutropenic patients by SnPCR, while the conventional blood culture could detect only 6 (11.3%) fungemia cases. The SnPCR had a sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 93%, 100%, 100%, 98%, and 98%, respectively, versus 43%, 100%, 100%, 83%, and 85%, respectively, for blood culture. The results by SnPCR alone showed almost perfect agreement with the results of the combined method (κ = 0.95) in the detection of BSFI. CONCLUSION: The SnPCR method proved to be better compared to blood culture for the early and accurate detection of BSFI in febrile neutropenic pediatric patients.

Background: We aimed to compare semi-nested PCR with indirect ELISA to diagnose human fasciolosis. Methods: Overall, 70 serum samples were collected from different areas in Iran suspected for fascioliasis. Individuals were classified based on diagnostic of fascioliasis and habitat in endemic areas. Finally, all serum samples were tested by indirect ELISA (using secretory excretory antigen) and semi-nested PCR (using ITS1 gene). The study was conducted in the School of Publish Health, Tehran University of Medical Sciences, Iran in 2021. Results: Significant differences were found between agreement and similarity of patients' results of indirect ELISA and semi-nested PCR 94.46% and 98.4% respectively (Cohen's kappa ≥0.6; P-value≤0.05). No cross-reactions were observed with other parasitic diseases (toxocariasis, hydatidosis, strongyloidiasis, toxoplasmosis, cutaneous leishmaniasis, taeniasis and trichinosis). 69.84% of samples were positive by both techniques. In addition, the percentage of agreement and similarity between the results of the two techniques based on habitat in endemic areas was 88.9-100% and 97.7-100%, respectively (Cohen's kappa ≥0.6; P-value≤0.05). Conclusion: Semi-nested PCR could be a suitable method for following up on patients' treatment and a confirmatory method for ELISA as for diagnosis of human fascioliasis.

Aim: The present study aimed to detect Babesia ovis and Babesia motasi in the blood samples of sheep and goats from Northwest of Iran by the semi-nested polymerase chain reaction (PCR) technique. Materials and Methods: A total of 166 whole blood samples (including 123 sheep and 43 goats) were collected. In the first stage, the PCR was performed to amplify a piece of 18S rRNA gene of Babesia and Theileria genera. Then, semi-nested PCR was carried out on all PCR products to differentiate B. ovis and B. motasi. Results: The PCR indicated that totally, 19 (11.44%) out of 166 samples were positive for Babesia or Theileria spp. The semi-nested PCR showed that 38 samples (22.89%) were positive only for B. ovis. No significant association was found between the infection rate of B. ovis and age, gender and species of animals. Conclusion: In the present study, there was no evidence for B. motasi infection in small ruminants from Northwest of Iran. Therefore, B. ovis was the main causative agent of ovine Babesiosis in this region.

Aim: The present study aimed to detect Babesia ovis and Babesia motasi in the blood samples of sheep and goats from Northwest of Iran by the semi-nested polymerase chain reaction (PCR) technique. Materials and Methods: A total of 166 whole blood samples (including 123 sheep and 43 goats) were collected. In the first stage, the PCR was performed to amplify a piece of 18S rRNA gene of Babesia and Theileria genera. Then, semi-nested PCR was carried out on all PCR products to differentiate B. ovis and B. motasi. Results: The PCR indicated that totally, 19 (11.44%) out of 166 samples were positive for Babesia or Theileria spp. The semi-nested PCR showed that 38 samples (22.89%) were positive only for B. ovis. No significant association was found between the infection rate of B. ovis and age, gender and species of animals. Conclusion: In the present study, there was no evidence for B. motasi infection in small ruminants from Northwest of Iran. Therefore, B. ovis was the main causative agent of ovine Babesiosis in this region. [ABSTRACT FROM AUTHOR]

Background: The incidence of fungal endophthalmitis has dramatically increased in recent years and rapid detection of fungi using nucleic acid-based amplification techniques is helpful in management. Aim: To evaluate semi-nested polymerase chain reaction (PCR) targeting internal transcribed spacer (ITS) region for detection of panfungal genome in ocular specimens. Statistical analysis used: Z test for two proportion. Materials and Methods: Standardization of PCR targeting ITS primers was carried out by determining analytical sensitivity and specificity. The sensitivity and specificity of PCR was determined by serial tenfold dilutions of C. albicans (ATCC 24433) DNA and DNA extracts of laboratory isolates of Aspergillus fumigatus , Fusarium lichenicola (4), other fungal and closely related bacterial strains and also human DNA. Semi-nested PCR was applied onto a total of 168 ocular specimens with clinically suspected fungal etiology during 2003-2005. Results and Conclusions: PCR was specific and sensitive to detect 1fg of fungal DNA with ITS primers. PCR detected fungal genome in 90 (53.57%) in comparison with the conventional technique, positive in 34 (20.23%) by smear examination and in 42 (25%) by culture. The increase in clinical sensitivity by 28.57% using PCR was found to be statistically significant { P < 0.001 using Z test for two proportion}. The accuracy of the test was found to be 70.85%. PCR proved to be a rapid diagnostic technique for detection of panfungal genome directly from clinical specimens

Introduction: Several studies have implicated Helicobacter pylori as a risk factor in laryngeal cancer, but other studies disagree. It is fundamental that the relationship between Helicobacter pylori and laryngeal cancer be verified in order to provide evidence of ways to prevent the initiation and development of this carcinoma. Materials and methods: In total, 81 patients with laryngeal squamous cell carcinoma and 75 control subjects were enrolled in a case-control study. Semi-nested polymerase chain reaction techniques were applied to detect Helicobacter pylori in the laryngeal mucosa and enzyme-linked immunosorbent assays were used to detect serum antibodies against Helicobacter pylori. Risk factors associated with laryngeal carcinoma were analyzed using logistic regression models. Results: The presence of Helicobacter pylori in the larynx was higher in patients with laryngeal cancer than in control subjects (71.6 vs. 25.3 %, p < 0.001). Among patients with laryngeal carcinoma, rates of Helicobacter pylori infection were higher in normal laryngeal tissues than in tumor tissues. After adjusting for confounding factors, regression analysis indicated that the microbe was an independent risk factor for laryngeal cancer (OR = 7.15, 95 % CI [3.29, 15.53], p < 0.001). Conclusions: This study suggests that Helicobacter pylori is present in the mucosa of the larynx. The microorganism may be an independent risk factor for laryngeal squamous cell carcinoma. The laryngeal mucosa thus provides a reservoir for the bacteria possibly, and is a likely staging place for its transmission to other areas. [ABSTRACT FROM AUTHOR]

Background: We aimed to compare semi-nested PCR with indirect ELISA to diagnose human fasciolosis., Methods: Overall, 70 serum samples were collected from different areas in Iran suspected for fascioliasis. Individuals were classified based on diagnostic of fascioliasis and habitat in endemic areas. Finally, all serum samples were tested by indirect ELISA (using secretory excretory antigen) and semi-nested PCR (using ITS1 gene). The study was conducted in the School of Publish Health, Tehran University of Medical Sciences, Iran in 2021., Results: Significant differences were found between agreement and similarity of patients' results of indirect ELISA and semi-nested PCR 94.46% and 98.4% respectively (Cohen's kappa ≥0.6; P -value≤0.05). No cross-reactions were observed with other parasitic diseases (toxocariasis, hydatidosis, strongyloidiasis, toxoplasmosis, cutaneous leishmaniasis, taeniasis and trichinosis). 69.84% of samples were positive by both techniques. In addition, the percentage of agreement and similarity between the results of the two techniques based on habitat in endemic areas was 88.9-100% and 97.7-100%, respectively (Cohen's kappa ≥0.6; P -value≤0.05)., Conclusion: Semi-nested PCR could be a suitable method for following up on patients' treatment and a confirmatory method for ELISA as for diagnosis of human fascioliasis., Competing Interests: Conflict of interest The authors declare that there is no conflict of interest., (Copyright © 2022 Alizadeh et al. Published by Tehran University of Medical Sciences.)

Burkholderia cepaciahas recently received a considerable attention as one of the major risks in susceptible pharmaceutical products. This microorganism can easily propagate and cause vast and severe contamination, especially to the water supplies for pharmaceutical companies. Moreover, it proliferates within the products and can cause severe infections for humans. Therefore, fast and sensitive detection of these bacteria is of a great demand. The present study introduces improved application of a polymerase chain reaction assay with relatively high sensitivity and specificity for the direct detection ofB. cepaciafrom the aqueous pharmaceutical products. A semi-nested polymerase chain reaction approach using the primer set BCR1/BCR2 followed by BCR1/Mr yielding a 465 bp fragment of the recA gene was applied and tested using both crude lysate from isolated colonies and DNA directly extracted from artificially prepared and spiked reference syrup. The polymerase chain reaction assay showed no interference with other bacterial reference and environmental strains tested, includingStaphylococcus aureusATCC® 6538,Pseudomonas aeruginosaATCC® 9027,Escherichia coliATCC® 8739,Salmonella abonyNCTC® 6017,Bacillus subtilisATCC® 6633,Micrococcus luteus, Staphylococcus warneri, Pseudomonas fluorescens, Pseudomonas putida, andRalstonia pickettii Moreover, this semi-nested assay showed a detection limit of around 10 colony-forming units per sample and could detectB. cepaciastrains isolated from a municipal pre-treated potable water tank. Comparing the results for detection ofB. cepaciain 100 randomly collected commercial syrup preparations using both conventional standard method and polymerase chain reaction assay revealed thatB. cepaciawas detected in two samples using polymerase chain reaction assay while all samples showed negative results by conventional culturing and biochemical methods. These results highlight the advantage of using this polymerase chain reaction assay to detectB. cepaciain contaminated pharmaceutical products and even water for pharmaceutical purposes, without the need of culturing or pre-enrichment, where it may give false-negative results and may be misidentified when biochemically tested., (© PDA, Inc. 2016.)